WorldWideScience

Sample records for twin mars exploration

  1. Exploring Mars

    Science.gov (United States)

    Breuil, Stéphanie

    2016-04-01

    Mars is our neighbour planet and has always fascinated humans as it has been seen as a potential abode for life. Knowledge about Mars is huge and was constructed step by step through numerous missions. It could be difficult to describe these missions, the associated technology, the results, the questions they raise, that's why an activity is proposed, that directly interests students. Their production is presented in the poster. Step 1: The main Mars feature and the first Mars explorations using telescope are presented to students. It should be really interesting to present "Mars Canals" from Percival Lowell as it should also warn students against flawed interpretation. Moreover, this study has raised the big question about extra-terrestrial life on Mars for the first time. Using Google Mars is then a good way to show the huge knowledge we have on the planet and to introduce modern missions. Step 2: Students have to choose and describe one of the Mars mission from ESA and NASA. They should work in pairs. Web sites from ESA and NASA are available and the teacher makes sure the main missions will be studied. Step 3: Students have to collect different pieces of information about the mission - When? Which technology? What were the main results? What type of questions does it raise? They prepare an oral presentation in the form they want (role play, academic presentation, using a poster, PowerPoint). They also have to produce playing cards about the mission that could be put on a timeline. Step 4: As a conclusion, the different cards concerning different missions are mixed. Groups of students receive cards and they have to put them on a timeline as fast as possible. It is also possible to play the game "timeline".

  2. MarsTwin: an M-mission to Mars with two geophysical laboratories

    Science.gov (United States)

    Dehant, V. M.; Breuer, D.; Grott, M.; Spohn, T.; Lognonne, P.; Read, P. L.; Vennerstroem, S.; Banerdt, B.

    2010-12-01

    Mars-Twin - a mission proposed for the running ESA cosmic vision M call - if selected it will be the first European mission to focus on interior processes and the early evolution of Mars, providing essential constraints for models of the thermal, geochemical, and geologic evolution of Mars and for a better understanding of SNC meteorites and future samples from Mars. Our fundamental understanding of the interior of the Earth comes from geophysics, geodesy, geochemistry, geomagnetism, and petrology. For geophysics, seismology, geodesy, magnetic field measurements, and surface heat flow have revealed the basic internal layering of the Earth, its thermal structure, its gross compositional stratification, as well as significant lateral variations in these quantities. The landers will also provide meteorological stations to monitor the Martian meteorology and climate and to obtain new measurements in the Martian boundary layer. The Mars-Twin mission will fill a longstanding gap in the scientific exploration of the solar system by performing an in-situ investigation of the interior of an Earth-like planet other than our own. Mars-Twin will provide unique and critical information about the fundamental processes of terrestrial planet formation and evolution. This investigation has been ranked as a high priority in virtually every set of European, US and international high-level planetary science recommendations for the past 30 years, and the objectives for the Mars-Twin mission are derived directly from these recommendations. In addition to geophysics, the mission will provide important constraints for the Astrobiology of Mars by helping to understand why Mars fails to have a magnetic field, by helping to understand the evolution of the climate, and by providing a limit to the chemoautrophic biosphere through a measurement of the heat flow. The paper will also address the synergy between the lander instruments and the possible orbiter instruments.

  3. On Mars Exploration Rovers - Spirit and Opportunity

    Institute of Scientific and Technical Information of China (English)

    李颖; 吴文忠

    2004-01-01

    NASA's twin Mars exploration rovers, now named Spirit and Opportunity, are designed to study the history of water on Mars. These robotic geologists are equipped with a robotic arm, a drilling tool, three spectrometers, and four pairs of cameras that allow them to have a human-like, 3D view of the terrain. Each rover could travel as far as 100 meters in one day to act as Mars scientists eyes and hands, exploring an environment where humans can't yet go.

  4. Exobiological exploration of Mars

    Science.gov (United States)

    Klein, H. P.; Devincenzi, D. L.

    1995-01-01

    Of all the other planets in the solar system, Mars remains the most promising for further elucidating concepts about chemical evolution and the origin of life. Strategies were developed to pursue three exobiological objectives for Mars exploration: determining the abundance and distribution of the biogenic elements and organic compounds, detecting evidence of an ancient biota on Mars, and determining whether indigenous organisms exist anywhere on the planet. The three strategies are quite similar and, in fact, share the same sequence of phases. In the first phase, each requires global reconnaissance and remote sensing by orbiters to select sites of interest for detailed in situ analyses. In the second phase, lander missions are conducted to characterize the chemical and physical properties of the selected sites. The third phase involves conducting 'critical' experiments at sites whose properties make them particularly attractive for exobiology. These critical experiments would include, for example, identification of organics, detection of fossils, and detection of extant life. The fourth phase is the detailed analysis of samples returned from these sites in Earth-based laboratories to confirm and extend previous discoveries. Finally, in the fifth phase, human exploration is needed to establish the geological settings for the earlier findings or to discover and explore sites that are not accessible to robotic spacecraft.

  5. Mars Exploration Rover mission

    Science.gov (United States)

    Crisp, Joy A.; Adler, Mark; Matijevic, Jacob R.; Squyres, Steven W.; Arvidson, Raymond E.; Kass, David M.

    2003-10-01

    In January 2004 the Mars Exploration Rover mission will land two rovers at two different landing sites that show possible evidence for past liquid-water activity. The spacecraft design is based on the Mars Pathfinder configuration for cruise and entry, descent, and landing. Each of the identical rovers is equipped with a science payload of two remote-sensing instruments that will view the surrounding terrain from the top of a mast, a robotic arm that can place three instruments and a rock abrasion tool on selected rock and soil samples, and several onboard magnets and calibration targets. Engineering sensors and components useful for science investigations include stereo navigation cameras, stereo hazard cameras in front and rear, wheel motors, wheel motor current and voltage, the wheels themselves for digging, gyros, accelerometers, and reference solar cell readings. Mission operations will allow commanding of the rover each Martian day, or sol, on the basis of the previous sol's data. Over a 90-sol mission lifetime, the rovers are expected to drive hundreds of meters while carrying out field geology investigations, exploration, and atmospheric characterization. The data products will be delivered to the Planetary Data System as integrated batch archives.

  6. Rotorcrafts for Mars Exploration

    Science.gov (United States)

    Balaram, J.; Tokumaru, P. T.

    2014-06-01

    Rotorcraft mobility provides a number of useful capabilities to potential Mars missions. We present some recent results relating to the design and test of Mars rotorcraft mobility elements, and aspects of rotorcraft system and mission design.

  7. Mars Exploration Science in 2050

    Science.gov (United States)

    Ehlmann, B. L.; Johnson, S. S.; Horgan, B.; Niles, P. B.; Amador, E. S.; Archer, P. D.; Byrne, S.; Edwards, C. S.; Fraeman, A. A.; Glavin, D. P.; Glotch, T. D.; Hardgrove, C.; Hayne, P. O.; Kite, E. S.; Lanza, N. L.; Lapotre, M. G. A.; Michalski, J.; Rice, M.; Rogers, A. D.

    2017-02-01

    We describe an approach to Mars exploration in 2050 and the decades leading in that couples fundamental science on the workings of planets and the search for life with collection of information on resources and hazards essential for human exploration.

  8. Mars Exploration Rover Heat Shield Recontact Analysis

    Science.gov (United States)

    Raiszadeh, Behzad; Desai, Prasun N.; Michelltree, Robert

    2011-01-01

    The twin Mars Exploration Rover missions landed successfully on Mars surface in January of 2004. Both missions used a parachute system to slow the rover s descent rate from supersonic to subsonic speeds. Shortly after parachute deployment, the heat shield, which protected the rover during the hypersonic entry phase of the mission, was jettisoned using push-off springs. Mission designers were concerned about the heat shield recontacting the lander after separation, so a separation analysis was conducted to quantify risks. This analysis was used to choose a proper heat shield ballast mass to ensure successful separation with low probability of recontact. This paper presents the details of such an analysis, its assumptions, and the results. During both landings, the radar was able to lock on to the heat shield, measuring its distance, as it descended away from the lander. This data is presented and is used to validate the heat shield separation/recontact analysis.

  9. Mathematics and Mars Exploration

    Science.gov (United States)

    Velasco, M. P.; Usero, D.; Jiménez, S.; Aguirre, C.; Vázquez, L.

    2015-01-01

    In this study we consider modelization associated with study of solar radiation at the surface of Mars and the Martian atmosphere. In particular, we present elements concerning retrieval of the solar irradiance spectrum on the surface of Mars from data collected by arrays of photodiodes, such as those onboard the "Curiosity" MSL-rover and other missions currently under design. By using these techniques we are able to provide an approximate description of the expected measures. In this work we have also developed a new method of tomography-based signal analysis for detection of events in the Martian atmosphere boundary layer, such as dust devils. In general, this method enables detection of events that occur briefly in time and are localized in space. This tomographic method allows us to identify the presence of more dust devils than detected previously using the same data. Finally we show new scenarios of modelization through fractional differential equations associated with diffusion processes and nonlocal problems. Such approaches could be used to model complex Martian dynamics.

  10. Mars' atmosphere: Earth's sister and statistical twin

    Science.gov (United States)

    Chen, Wilbur; Lovejoy, Shaun; Muller, Jan-Peter

    2016-04-01

    Satellite-based Martian re-analyses have allowed unprecedented comparisons between our atmosphere and that of our sister planet, underlining various similarities and differences in their respective dynamics. Yet by focusing on large scale structures and deterministic mechanisms they have improved our understanding of the dynamics only over fairly narrow ranges of (near) planetary scales. However, the Reynolds numbers of the flows on both planets are larger than 1011 and dissipation only occurs at centimetric (Mars) or millimetric scales (Earth) so that over most of their scale ranges, the dynamics are fully turbulent. In this presentation, we therefore examine the high level, statistical, turbulent laws for the temperature, horizontal wind and surface pressure, finding that Earth and Mars have virtually identical statistical exponents: their statistics are very similar over wide ranges. Therefore, it would seem that with the exception of certain aspects of the largest scales (such as the role of dust in atmospheric heating on Mars, or of water in its various phases on Earth), that the nonlinear dynamics are very similar. We argue that this is a prediction of the classical laws of turbulence when extended to planetary scales, and that it supports our use of turbulent laws on both planetary atmospheres.

  11. Exploring Mars. Grades 5-12.

    Science.gov (United States)

    Treiman, Allan; And Others

    This learning guide provides detailed information about exploring the planet Mars. The guide covers a variety of topics related to space exploration including: (1) the reasons for exploring Mars; (2) a history of the exploration of and thinking about Mars beginning with the Babylonians and continuing through the Viking missions; (3) the status of…

  12. The Mars Exploration Program: Past, Present and Future (?)

    Science.gov (United States)

    Hubbard, Scott

    NASA's Mars Exploration Program was redesigned in 2000, following the twin losses of the Mars Climate Orbiter and Mars Polar Lander in late 1999. The new science based program was grounded in community consensus based priorities and had as its aim understanding Mars as a system. The popular phrase used to describe the goals of the mission sequence was "Follow the Water". A new queue of missions was put in place for the decade 2001 - 2010 and a new community based competitive opportunity, the Mars Scout program, was initiated. The strategic mission implementation has been unchanged since the new program was announced in October 2000. Those projects successfully launched and deployed thus far include Mars Odyssey, the two Mars rovers Spirit and Opportunity, Mars Reconnaissance Obiter and the Phoenix Scout Mission. The final project of the decade, the Mars Science Laboratory, is in the last stages of development with launch slated for the Fall of 2009. The President's budget announced in February 2008 for Fiscal 2009, contained little in the way of definitive objectives for Mars program in the decade 2011-2020 and proposed to reduce the Mars budget drastically over the five year budget period. This paper will review the programmatic and scientific progress thus far in meeting the original objectives as outlined in October 2000. A look ahead to the potential missions and goals for the next decade will be provided with particular emphasis on the status of Mars Sample Return mission. Bibliography: G. Scott Hubbard, Firouz M. Naderi, James B. Garvin, Following the water, the new program for Mars exploration, Acta Astronautica 51(1-9):337-350, 2002.

  13. A Mars Exploration Discovery Program

    Science.gov (United States)

    Hansen, C. J.; Paige, D. A.

    2000-07-01

    The Mars Exploration Program should consider following the Discovery Program model. In the Discovery Program a team of scientists led by a PI develop the science goals of their mission, decide what payload achieves the necessary measurements most effectively, and then choose a spacecraft with the capabilities needed to carry the payload to the desired target body. The primary constraints associated with the Discovery missions are time and money. The proposer must convince reviewers that their mission has scientific merit and is feasible. Every Announcement of Opportunity has resulted in a collection of creative ideas that fit within advertised constraints. Following this model, a "Mars Discovery Program" would issue an Announcement of Opportunity for each launch opportunity with schedule constraints dictated by the launch window and fiscal constraints in accord with the program budget. All else would be left to the proposer to choose, based on the science the team wants to accomplish, consistent with the program theme of "Life, Climate and Resources". A proposer could propose a lander, an orbiter, a fleet of SCOUT vehicles or penetrators, an airplane, a balloon mission, a large rover, a small rover, etc. depending on what made the most sense for the science investigation and payload. As in the Discovery program, overall feasibility relative to cost, schedule and technology readiness would be evaluated and be part of the selection process.

  14. Astrobiology and the Human Exploration of Mars

    Science.gov (United States)

    Levine, Joel S.; Garvin, James B.; Drake, B. G.; Beaty, David

    2010-01-01

    In March 2007, the Mars Exploration Program Analysis Group (MEPAG) chartered the Human Exploration of Mars Science Analysis Group (HEM-SAG), co-chaired by J. B. Garvin and J. S. Levine and consisting of about 30 Mars scientists from the U.S. and Europe. HEM-SAG was one of a half dozen teams charted by NASA to consider the human exploration of Mars. Other teams included: Mars Entry, Descent and Landing, Human Health and Performance, Flight and Surface Systems, and Heliospheric/Astrophysics. The results of these Mars teams and the development of an architecture for the human exploration of Mars were summarized in two recent publications: Human Exploration of Mars Design Reference Architecture 5.0, NASA Special Publication-2009-566 (B. G. Drake, Editor), 100 pages, July 2009 and Human Exploration of Mars Design Reference Architecture 5.0, NASA Special Publication-2009-566 Addendum (B. G. Drake, Editor), 406 pages, July 2009. This presentation summarizes the HEM-SAG conclusions on astrobiology and the search for life on Mars by humans.

  15. Connecting Robots and Humans in Mars Exploration

    Science.gov (United States)

    Friedman, Louis

    2000-07-01

    Mars exploration is a very special public interest. It's preeminence in the national space policy calling for "sustained robotic presence on the surface," international space policy (witness the now aborted international plan for sample return, and also aborted Russian "national Mars program") and the media attention to Mars exploration are two manifestations of that interest. Among a large segment of the public there is an implicit (mis)understanding that we are sending humans to Mars. Even among those who know that isn't already a national or international policy, many think it is the next human exploration goal. At the same time the resources for Mars exploration in the U.S. and other country's space programs are a very small part of space budgets. Very little is being applied to direct preparations for human flight. This was true before the 1999 mission losses in the United States, and it is more true today. The author's thesis is that the public interest and the space program response to Mars exploration are inconsistent. This inconsistency probably results from an explicit space policy contradiction: Mars exploration is popular because of the implicit pull of Mars as the target for human exploration, but no synergy is permitted between the human and robotic programs to carry out the program. It is not permitted because of narrow, political thinking. In this paper we try to lay out the case for overcoming that thinking, even while not committing to any premature political initiative. This paper sets out a rationale for Mars exploration and uses it to then define recommended elements of the programs: missions, science objectives, technology. That consideration is broader than the immediate issue of recovering from the failures of Mars Climate OrbIter, Mars Polar Lander and the Deep Space 2 microprobes in late 1999. But we cannot ignore those failures. They are causing a slow down Mars exploration. Not only were the three missions lost, with their planned

  16. Enabling Tethered Exploration on Mars Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Strong science motivations exist for exploring hard to reach terrain on Mars and the leading systems proposed to do so require tethers. While tethers are used...

  17. Slope Morphology of Twin Peaks, Mars Pathfinder Landing Site

    Science.gov (United States)

    Hobbs, Steven; Paine, Colin; Clarke, Jon; Caprarelli, Graziella

    2010-05-01

    Development of slope form over time has long been a concern of geomorphologists, although recently this concern has been moved to slope processes rather than form. There are two basic approaches. The first is theoretical, involving modeling of different types and rates of processes, and calculation of results in terms of slope evolution over time. Comparisons with real-life slopes can follow this approach [1], [2]. The second, inductive, approach involves field measurements to test ideas about slope evolution starting from the assumption that observed slopes represent different stages of an essentially similar evolution [3]. Space is substituted for time, and a number of slopes, assumed to be of increasing age, are measured and placed in an evolutionary sequence (e.g. [4], [5], [6]). [5] showed that slope angles are modally distributed, with the modal angles controlled by the materials (regolith) of which the slopes are formed, and by the processes operating on them. Data can be obtained directly from field work or from digital elevation models (DEM) derived from remote sensing investigations [7]. DEMs are particularly useful to study inaccessible planets, such as Mars, where on site observations are restricted to only a few landing sites. Here we present a study of slopes on the Twin Peaks, two small hills located 780 m north and 910 m south of the Mars Pathfinder landing site at the mouth of the Ares and Tiu flood channels. The presence of streamlined hills, jumbled surfaces and conglomerates suggested the region was modified by massive flooding 1.8 - 3.5 billion years ago [8], [9]. The streamlined forms and terraces of the Twin Peaks were taken to indicate catastrophic flood conditions that were believed to be prevalent in the area [8]. It was also suggested that the northernmost peak was topped by floodwater, causing its flatter appearance. Other researchers postulated alternative geomorphological origins for the features observed at the Pathfinder landing site

  18. Exploring the origins of asthma: Lessons from twin studies

    Science.gov (United States)

    2014-01-01

    This thesis explores the contribution of twin studies, particularly those studies originating from the Danish Twin Registry, to the understanding of the aetiology of asthma. First, it is explored how twin studies have established the contribution of genetic and environmental factors to the variation in the susceptibility to asthma, and to the variation in several aspects of the clinical expression of the disease such as its age at onset, its symptomatology, its intermediate phenotypes, and its relationship with other atopic diseases. Next, it is explored how twin studies have corroborated theories explaining asthma's recent increase in prevalence, and last, how these fit with the explanations of the epidemiological trends in other common chronic diseases of modernity. PMID:26557247

  19. Cryogenics and the Human Exploration of Mars

    Science.gov (United States)

    Salerno, Louis J.; Kittel, Peter; Rasky, Daniel J. (Technical Monitor)

    1997-01-01

    Current plans within NASA involve extending the human exploration of space from low earth orbit into the solar system, with the first human exploration of Mars presently planned in 2011. Integral to all hum Mars mission phases is cryogenic fluid management. Cryogenic fluids will be required both as propellant and for In-Situ Resource Utilization (ISRU). Without safe and efficient cryogen storage human Mars missions will not be possible. Effective control and handling of cryogenic fluids is the key to affordable Mars missions, and advancing active thermal control technology is synergistic with all of NASA's exploration initiatives and with existing and future instrument cooling programs, including MTPE and Origins. Present mission scenarios for human exploration require cryogenic propellant storage for up to 1700 days and for up to 60 metric tons. These requirements represent increases of an order of magnitude over previous storage masses and lifetimes. The key cryogenic terminology areas to be addressed in human Mars missions are long-term propellant storage, cryogenic refrigeration, cryogenic liquefaction, and zero gravity fluid management. Long-term storage for the thermal control of cryogenic propellants is best accomplished with a mix of passive and active technologies. Passive technologies such as advanced multilayer insulation (MLI) concepts will be combined with the development of active coolers (cryogenic refrigerators). Candidates for long-life active cooling applications include Reverse Turbo-Brayton, Stirling, and Pulse-Tube coolers. The integration of passive and active technologies will form a hybrid system optimized to minimize the launch mass while preserving the cryogenic propellants. Since cryogenic propellants are the largest mass that Mars missions must launch from earth, even a modest reduction in the percentage of propellant carried results in a significant weight saving. This paper will present a brief overview of cryogenic fluid management

  20. Mars Exploration Rover thermal test program overview

    Science.gov (United States)

    Pauken, Michael T.; Kinsella, Gary; Novak, Keith; Tsuyuki, Glenn

    2004-01-01

    In January 2004, two Mars Exploration Rovers (MER) landed on the surface of Mars to begin their mission as robotic geologists. A year prior to these historic landings, both rovers and the spacecraft that delivered them to Mars, were completing a series of environmental tests in facilities at the Jet Propulsion Laboratory. This paper describes the test program undertaken to validate the thermal design and verify the workmanship integrity of both rovers and the spacecraft. The spacecraft, which contained the rover within the aeroshell, were tested in a 7.5 m diameter thermal vacuum chamber. Thermal balance was performed for the near earth (hot case) condition and for the near Mars (cold case) condition. A solar simulator was used to provide the solar boundary condition on the solar array. IR lamps were used to simulate the solar heat load on the aeroshell for the off-sun attitudes experienced by the spacecraft during its cruise to Mars. Each rover was tested separately in a 3.0 m diameter thermal vacuum chamber over conditions simulating the warmest and coldest expected Mars diurnal temperature cycles. The environmental tests were conducted in a quiescent nitrogen atmosphere at a pressure of 8 to 10 Torr. In addition to thermal balance testing, the science instruments on board the rovers were tested successfully in the extreme environmental conditions anticipated for the mission. A solar simulator was not used in these tests.

  1. Combining meteorites and missions to explore Mars.

    Science.gov (United States)

    McCoy, Timothy J; Corrigan, Catherine M; Herd, Christopher D K

    2011-11-29

    Laboratory studies of meteorites and robotic exploration of Mars reveal scant atmosphere, no evidence of plate tectonics, past evidence for abundant water, and a protracted igneous evolution. Despite indirect hints, direct evidence of a martian origin came with the discovery of trapped atmospheric gases in one meteorite. Since then, the study of martian meteorites and findings from missions have been linked. Although the meteorite source locations are unknown, impact ejection modeling and spectral mapping of Mars suggest derivation from small craters in terrains of Amazonian to Hesperian age. Whereas most martian meteorites are young ( 4.5 Ga and formation of enriched and depleted reservoirs. However, the history inferred from martian meteorites conflicts with results from recent Mars missions, calling into doubt whether the igneous histor y inferred from the meteorites is applicable to Mars as a whole. Allan Hills 84001 dates to 4.09 Ga and contains fluid-deposited carbonates. Accompanying debate about the mechanism and temperature of origin of the carbonates came several features suggestive of past microbial life in the carbonates. Although highly disputed, the suggestion spurred interest in habitable extreme environments on Earth and throughout the Solar System. A flotilla of subsequent spacecraft has redefined Mars from a volcanic planet to a hydrologically active planet that may have harbored life. Understanding the history and habitability of Mars depends on understanding the coupling of the atmosphere, surface, and subsurface. Sample return that brings back direct evidence from these diverse reservoirs is essential.

  2. The case for Mars III: Strategies for exploration - Technical

    Science.gov (United States)

    Stoker, Carol R. (Editor)

    1989-01-01

    Papers on issues related to Mars exploration are presented, covering topics such as the social implications of manned missions to Mars, mission strategies, mission designs, the economics of a Mars mission, Space Station support for a Mars mission, a Diagnostic and Environmental Monitoring System, and a zero-g CELSS/recreation facility for an earth/Mars crew shuttle. Other topics include biomedical concerns and fitness in spaceflight, spaceflight environment habitability, the Mars Rover/Sample Return Mission, a rooitic Mars surface sampler, a Mars Orbiter, and scientific goals of Mars exploration. Additional topics include Space Station evolution, mission options, modeling advanced space systems, computer support for Mars missions, launch system options, advanced propulsion techniques, the utilization of resources on Mars, the development of a Martian base, and options for mobility on Mars.

  3. Flux-gate magnetometer for Mars exploration

    Science.gov (United States)

    Zhao, Hua; Zhu, G. W.; Yu, P.; Wang, J. D.; Yu, M. F.; Li, L.; Sun, Y. Q.; Chen, S. W.; Liao, H. Z.; Zhou, B.; Feng, Y. Y.

    2008-10-01

    A micro-satellite, Yinghuo-1, would be launched with Russian spacecraft, Phobos-Grunt in October, 2009 to investigate the space environment around Mars. YH-1 and Phobos-Grunt forms a two-point measurement configuration in the Martian space environment. YH-1 and Phobos-Grunt are equipped with similar magnetic field and plasma detecting payload on two spacecraft would give some coordinated exploration around Mars. YH-1 would orbit Mars with periapsis of 800 km above the Martian surface, and apoapsis about 80000km to the center of Mars. The orbit inclination is in the range of 0~7° to the Martian equator. A flux-gate type magnetometer, with two tri-axial sensors, is developed for YH-1 spacecraft. Two sensors are mounted on one-side of the deployable solar panel with a radial separation about 45cm to function as a gradiometer to minimize the affects of platform remanence. The dynamic range of the magnetometer is +/-256nT with a 16-bit ADC converter, and the noise level is better than 0.01nT/√Hz, to measure three-component magnetic field from DC to 10Hz. Flux-gate magnetometer would work together with the Plasma Package onboard of YH-1 to investigate the Martian bow shock, magnetosheath, magnetic pileup region (MPR). A detail description of the flux-gate magnetometer is presented in this paper, with test and calibration results.

  4. Lunar and Mars Exploration: The Autonomy Factor

    Science.gov (United States)

    Rando, Cynthia M.; Schuh, Susan V.

    2008-01-01

    Long duration space flight crews have relied heavily on almost constant communication with ground control mission support. Ground control teams provide vehicle status and system monitoring, while offering near real time support for specific tasks, emergencies, and ensuring crew health and well being. With extended exploration goals to lunar and Mars outposts, real time communication with ground control teams and the ground s ability to conduct mission monitoring will be very limited compared to the resources provided to current International Space Station (ISS) crews. An operational shift toward more autonomy and a heavier reliance on the crew to monitor their vehicle and operations will be required for these future missions. NASA s future exploration endeavors and the subsequent increased autonomy will require a shift in crew skill composition, i.e. engineer, doctor, mission specialist etc. and lead to new training challenges and mission scenarios. Specifically, operational and design changes will be necessary in many areas including: Habitat Infrastructure and Support Systems, Crew Composition, Training, Procedures and Mission Planning. This paper will specifically address how to apply ISS lessons learned to further use ISS as a test bed to address decreased amounts of ground support to achieve full autonomous operations for lunar and Mars missions. Understanding these lessons learned and applying them to current operations will help to address the future impacts of increased crew autonomy for the lunar and Mars outposts and pave the way for success in increasingly longer mission durations.

  5. Operations Strategies for the Mars Exploration Rovers During the 2007 Martian Global Dust Storm

    Science.gov (United States)

    Seibert, Michael; Herman, Jennifer; ElDeeb, Dina

    2009-01-01

    In June and July 2007 Mars experienced a dust storm that grew to envelop all but the polar latitudes of the planet. This dust storm was the first global dust storm to occur while the twin Mars Exploration Rovers (MER) began surface operations. It is estimated that the dust in the atmosphere prevented over 99.6% of direct sunlight from reaching the surface at the peak of the storm. Data collected indicated that solar array energy output was reduced to approximately 15% of maximum. The reduction in insolation and energy output posed the greatest risk of ending the mission for both rovers at that time.

  6. Muon radiography for exploration of Mars geology

    Directory of Open Access Journals (Sweden)

    S. Kedar

    2013-06-01

    Full Text Available Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays to image the interior of large-scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  7. Muon radiography for exploration of Mars geology

    Directory of Open Access Journals (Sweden)

    S. Kedar

    2012-10-01

    Full Text Available Muon radiography is a technique that uses naturally occurring showers of muons (penetrating particles generated by cosmic rays to image the interior of large scale geological structures in much the same way as standard X-ray radiography is used to image the interior of smaller objects. Recent developments and application of the technique to terrestrial volcanoes have demonstrated that a low-power, passive muon detector can peer deep into geological structures up to several kilometers in size, and provide crisp density profile images of their interior at ten meter scale resolution. Preliminary estimates of muon production on Mars indicate that the near horizontal Martian muon flux, which could be used for muon radiography, is as strong or stronger than that on Earth, making the technique suitable for exploration of numerous high priority geological targets on Mars. The high spatial resolution of muon radiography also makes the technique particularly suited for the discovery and delineation of Martian caverns, the most likely planetary environment for biological activity. As a passive imaging technique, muon radiography uses the perpetually present background cosmic ray radiation as the energy source for probing the interior of structures from the surface of the planet. The passive nature of the measurements provides an opportunity for a low power and low data rate instrument for planetary exploration that could operate as a scientifically valuable primary or secondary instrument in a variety of settings, with minimal impact on the mission's other instruments and operation.

  8. Research from the NASA Twins Study and Omics in Support of Mars Missions

    Science.gov (United States)

    Kundrot, C.; Shelhamer, M.; Scott, G.

    2015-01-01

    The NASA Twins Study, NASA's first foray into integrated omic studies in humans, illustrates how an integrated omics approach can be brought to bear on the challenges to human health and performance on a Mars mission. The NASA Twins Study involves US Astronaut Scott Kelly and his identical twin brother, Mark Kelly, a retired US Astronaut. No other opportunity to study a twin pair for a prolonged period with one subject in space and one on the ground is available for the foreseeable future. A team of 10 principal investigators are conducting the Twins Study, examining a very broad range of biological functions including the genome, epigenome, transcriptome, proteome, metabolome, gut microbiome, immunological response to vaccinations, indicators of atherosclerosis, physiological fluid shifts, and cognition. A novel aspect of the study is the integrated study of molecular, physiological, cognitive, and microbiological properties. Major sample and data collection from both subjects for this study began approximately six months before Scott Kelly's one year mission on the ISS, continue while Scott Kelly is in flight and will conclude approximately six months after his return to Earth. Mark Kelly will remain on Earth during this study, in a lifestyle unconstrained by this study, thereby providing a measure of normal variation in the properties being studied. An overview of initial results and the future plans will be described as well as the technological and ethical issues raised for spaceflight studies involving omics.

  9. Perchlorate Reduction by Yeast for Mars Exploration

    Science.gov (United States)

    Sharma, Alaisha

    2015-01-01

    Martian soil contains high levels (0.6 percentage by mass) of calcium perchlorate (Ca(ClO4)2), which readily dissociates into calcium and the perchlorate ion (ClO4-) in water. Even in trace amounts, perchlorates are toxic to humans and have been implicated in thyroid dysfunction. Devising methods to lessen perchlorate contamination is crucial to minimizing the health risks associated with human exploration and colonization of Mars. We designed a perchlorate reduction pathway, which sequentially reduces perchlorate to chloride (Cl-) and oxygen (O2), for implementation in the yeast Saccharomyces cerevisiae. Using genes obtained from perchlorate reducing bacteria Azospira oryzae and Dechloromonas aromatica, we plan to assemble this pathway directly within S. cerevisiae through recombinational cloning. A perchlorate reduction pathway would enable S. cerevisiae to lower perchlorate levels and produce oxygen, which may be harvested or used directly by S. cerevisiae for aerobic growth and compound synthesis. Moreover, using perchlorate as an external electron acceptor could improve the efficiency of redox-imbalanced production pathways in yeast. Although several perchlorate reducing bacteria have been identified and utilized in water treatment systems on Earth, the widespread use of S. cerevisiae as a synthetic biology platform justifies the development of a perchlorate reducing strain for implementation on Mars.

  10. Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation

    Science.gov (United States)

    Bell, J.F.; Squyres, S. W.; Herkenhoff, K. E.; Maki, J.N.; Arneson, H.M.; Brown, D.; Collins, S.A.; Dingizian, A.; Elliot, S.T.; Hagerott, E.C.; Hayes, A.G.; Johnson, M.J.; Johnson, J. R.; Joseph, J.; Kinch, K.; Lemmon, M.T.; Morris, R.V.; Scherr, L.; Schwochert, M.; Shepard, M.K.; Smith, G.H.; Sohl-Dickstein, J. N.; Sullivan, R.J.; Sullivan, W.T.; Wadsworth, M.

    2003-01-01

    The Panoramic Camera (Pancam) investigation is part of the Athena science payload launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The scientific goals of the Pancam investigation are to assess the high-resolution morphology, topography, and geologic context of each MER landing site, to obtain color images to constrain the mineralogic, photometric, and physical properties of surface materials, and to determine dust and aerosol opacity and physical properties from direct imaging of the Sun and sky. Pancam also provides mission support measurements for the rovers, including Sun-finding for rover navigation, hazard identification and digital terrain modeling to help guide long-term rover traverse decisions, high-resolution imaging to help guide the selection of in situ sampling targets, and acquisition of education and public outreach products. The Pancam optical, mechanical, and electronics design were optimized to achieve these science and mission support goals. Pancam is a multispectral, stereoscopic, panoramic imaging system consisting of two digital cameras mounted on a mast 1.5 m above the Martian surface. The mast allows Pancam to image the full 360?? in azimuth and ??90?? in elevation. Each Pancam camera utilizes a 1024 ?? 1024 active imaging area frame transfer CCD detector array. The Pancam optics have an effective focal length of 43 mm and a focal ratio f/20, yielding an instantaneous field of view of 0.27 mrad/pixel and a field of view of 16?? ?? 16??. Each rover's two Pancam "eyes" are separated by 30 cm and have a 1?? toe-in to provide adequate stereo parallax. Each eye also includes a small eight position filter wheel to allow surface mineralogic studies, multispectral sky imaging, and direct Sun imaging in the 400-1100 nm wavelength region. Pancam was designed and calibrated to operate within specifications on Mars at temperatures from -55?? to +5??C. An onboard calibration target and fiducial marks provide the capability

  11. Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation

    Science.gov (United States)

    Bell, J. F.; Squyres, S. W.; Herkenhoff, K. E.; Maki, J. N.; Arneson, H. M.; Brown, D.; Collins, S. A.; Dingizian, A.; Elliot, S. T.; Hagerott, E. C.; Hayes, A. G.; Johnson, M. J.; Johnson, J. R.; Joseph, J.; Kinch, K.; Lemmon, M. T.; Morris, R. V.; Scherr, L.; Schwochert, M.; Shepard, M. K.; Smith, G. H.; Sohl-Dickstein, J. N.; Sullivan, R. J.; Sullivan, W. T.; Wadsworth, M.

    2003-11-01

    The Panoramic Camera (Pancam) investigation is part of the Athena science payload launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The scientific goals of the Pancam investigation are to assess the high-resolution morphology, topography, and geologic context of each MER landing site, to obtain color images to constrain the mineralogic, photometric, and physical properties of surface materials, and to determine dust and aerosol opacity and physical properties from direct imaging of the Sun and sky. Pancam also provides mission support measurements for the rovers, including Sun-finding for rover navigation, hazard identification and digital terrain modeling to help guide long-term rover traverse decisions, high-resolution imaging to help guide the selection of in situ sampling targets, and acquisition of education and public outreach products. The Pancam optical, mechanical, and electronics design were optimized to achieve these science and mission support goals. Pancam is a multispectral, stereoscopic, panoramic imaging system consisting of two digital cameras mounted on a mast 1.5 m above the Martian surface. The mast allows Pancam to image the full 360° in azimuth and +/-90° in elevation. Each Pancam camera utilizes a 1024 × 1024 active imaging area frame transfer CCD detector array. The Pancam optics have an effective focal length of 43 mm and a focal ratio of f/20, yielding an instantaneous field of view of 0.27 mrad/pixel and a field of view of 16° × 16°. Each rover's two Pancam ``eyes'' are separated by 30 cm and have a 1° toe-in to provide adequate stereo parallax. Each eye also includes a small eight position filter wheel to allow surface mineralogic studies, multispectral sky imaging, and direct Sun imaging in the 400-1100 nm wavelength region. Pancam was designed and calibrated to operate within specifications on Mars at temperatures from -55° to +5°C. An onboard calibration target and fiducial marks provide the

  12. Exploring Mars: The Ares Payload Service (APS)

    Science.gov (United States)

    Bowen, Justin; Lusignan, Bruce

    1999-08-01

    design notably an improved re-entry cooling system and fueling stability analysis were done this year. More technical detail and a proposed international consortium to develop the SSTO is presented in another session of this year's Mars convention. We believe that there will be no human exploration of Mars based on the Shuttle or Expendable launch vehicles, and no resources available except for a cooperative international program. However, just as the world is learning to cooperate in peacekeeping, we hold out the hope that similar cooperation will develop for Mars exploration. With that in mind, this year we asked the question- "How will the human mission get to Mars if it has to use the SsTO for transportation?"

  13. Boots on Mars: Earth Independent Human Exploration of Mars

    Science.gov (United States)

    Burnett, Josephine; Gill, Tracy R.; Ellis, Kim Gina

    2017-01-01

    This package is for the conduct of a workshop during the International Space University Space Studies Program in the summer of 2017 being held in Cork, Ireland. It gives publicly available information on NASA and international plans to move beyond low Earth orbit to Mars and discusses challenges and capabilities. This information will provide the participants a basic level of insight to develop a response on their perceived obstacles to a future vision of humans on Mars.

  14. Human Exploration of Mars Design Reference Architecture 5.0

    Science.gov (United States)

    Drake, Bret G.

    2010-01-01

    This paper provides a summary of the Mars Design Reference Architecture 5.0 (DRA 5.0), which is the latest in a series of NASA Mars reference missions. It provides a vision of one potential approach to human Mars exploration. The reference architecture provides a common framework for future planning of systems concepts, technology development, and operational testing as well as Mars robotic missions, research that is conducted on the International Space Station, and future lunar exploration missions. This summary the Mars DRA 5.0 provides an overview of the overall mission approach, surface strategy and exploration goals, as well as the key systems and challenges for the first three human missions to Mars.

  15. An exobiology science strategy for Mars exploration. [Abstract only

    Science.gov (United States)

    Klein, H. P.; Devincenzi, D. L.

    1994-01-01

    Of all the other planets in the solar system, Mars remains the most promising for further elucidating concepts about chemical evolution and the origin of life. Exobiological objectives for Mars exploration include: determining the abundance and distribution of the biogenic elements and organic compounds, detecting evidence of an ancient biota on Mars, and determining whether indigenous organisms exist anywhere on the planet. Both approved and planned missions to Mars were evaluated for their potential to contribute to the understanding of these exobiology science objectives and an exploration strategy was developed for each objective.

  16. On Mars: Exploration of the Red Planet, 1958 - 1978

    Science.gov (United States)

    Ezell, E. C. (Editor); Ezell, L. N. (Editor)

    1984-01-01

    The exploration of Mars is covered by the following topics: Mariner spacecraft and launch vehicles, search for Martian life; Voyager spacecraft; creation of Viking; Viking Orbiter and its Mariner inheritance; Viking lander; building a complex spacecraft; selecting landing sites; site certification, and data from Mars.

  17. Robotic Exploration of Moon and Mars: Thematic Education Approach

    Science.gov (United States)

    Allen, J S.; Tobola, K. W.; Lowes, L. L.; Betrue, R.

    2008-01-01

    Safe, sustained, affordable human and robotic exploration of the Moon, Mars, and beyond is a major NASA goal. Robotic exploration of the Moon and Mars will help pave the way for an expanded human presence in our solar system. To help share the robotic exploration role in the Vision for Space Exploration with classrooms, informal education groups, and the public, our team researched and consolidated the thematic story components and associated education activities into a useful education materials set for educators. We developed the set of materials for a workshop combining NASA Science Mission Directorate and Exploration Systems Mission Directorate engineering, science, and technology to train informal educators on education activities that support the robotic exploration themes. A major focus is on the use of robotic spacecraft and instruments to explore and prepare for the human exploration of the Moon and Mars.

  18. Relay Telecommunications for the Coming Decade of Mars Exploration

    Science.gov (United States)

    Edwards, C.; DePaula, R.

    2010-01-01

    Over the past decade, an evolving network of relay-equipped orbiters has advanced our capabilities for Mars exploration. NASA's Mars Global Surveyor, 2001 Mars Odyssey, and Mars Reconnaissance Orbiter (MRO), as well as ESA's Mars Express Orbiter, have provided telecommunications relay services to the 2003 Mars Exploration Rovers, Spirit and Opportunity, and to the 2007 Phoenix Lander. Based on these successes, a roadmap for continued Mars relay services is in place for the coming decade. MRO and Odyssey will provide key relay support to the 2011 Mars Science Laboratory (MSL) mission, including capture of critical event telemetry during entry, descent, and landing, as well as support for command and telemetry during surface operations, utilizing new capabilities of the Electra relay payload on MRO and the Electra-Lite payload on MSL to allow significant increase in data return relative to earlier missions. Over the remainder of the decade a number of additional orbiter and lander missions are planned, representing new orbital relay service providers and new landed relay users. In this paper we will outline this Mars relay roadmap, quantifying relay performance over time, illustrating planned support scenarios, and identifying key challenges and technology infusion opportunities.

  19. Relay Telecommunications for the Coming Decade of Mars Exploration

    Science.gov (United States)

    Edwards, C.; DePaula, R.

    2010-01-01

    Over the past decade, an evolving network of relay-equipped orbiters has advanced our capabilities for Mars exploration. NASA's Mars Global Surveyor, 2001 Mars Odyssey, and Mars Reconnaissance Orbiter (MRO), as well as ESA's Mars Express Orbiter, have provided telecommunications relay services to the 2003 Mars Exploration Rovers, Spirit and Opportunity, and to the 2007 Phoenix Lander. Based on these successes, a roadmap for continued Mars relay services is in place for the coming decade. MRO and Odyssey will provide key relay support to the 2011 Mars Science Laboratory (MSL) mission, including capture of critical event telemetry during entry, descent, and landing, as well as support for command and telemetry during surface operations, utilizing new capabilities of the Electra relay payload on MRO and the Electra-Lite payload on MSL to allow significant increase in data return relative to earlier missions. Over the remainder of the decade a number of additional orbiter and lander missions are planned, representing new orbital relay service providers and new landed relay users. In this paper we will outline this Mars relay roadmap, quantifying relay performance over time, illustrating planned support scenarios, and identifying key challenges and technology infusion opportunities.

  20. Thermal Design Overview of the Mars Exploration Rover Project

    Science.gov (United States)

    Tsuyuki, Glenn

    2001-01-01

    This slide presentation reviews the thermal design for the Mars exploration rover project. It includes information on the spacecraft configuration, the cruise scenario, landing scenario, instrument package, thermal environment, and spacecraft schematics.

  1. NASA's New Mars Exploration Program: The Trajectory of Knowledge

    Science.gov (United States)

    Garvin, James B.; Figueroa, Orlando; Naderi, Firouz M.

    2001-12-01

    NASA's newly restructured Mars Exploration Program (MEP) is finally on the way to Mars with the successful April 7 launch of the 2001 Mars Odyssey Orbiter. In addition, the announcement by the Bush Administration that the exploration of Mars will be a priority within NASA's Office of Space Science further cements the first decade of the new millennium as one of the major thrusts to understand the "new" Mars. Over the course of the past year and a half, an integrated team of managers, scientists, and engineers has crafted a revamped MEP to respond to the scientific as well as management and resource challenges associated with deep space exploration of the Red Planet. This article describes the new program from the perspective of its guiding philosophies, major events, and scientific strategy. It is intended to serve as a roadmap to the next 10-15 years of Mars exploration from the NASA viewpoint. [For further details, see the Mars Exploration Program web site (URL): http://mars.jpl.nasa.gov]. The new MEP will certainly evolve in response to discoveries, to successes, and potentially to setbacks as well. However, the design of the restructured strategy is attentive to risks, and a major attempt to instill resiliency in the program has been adopted. Mars beckons, and the next decade of exploration should provide the impetus for a follow-on decade in which multiple sample returns and other major program directions are executed. Ultimately the vision to consider the first human scientific expeditions to the Red Planet will be enabled. By the end of the first decade of this program, we may know where and how to look for the elusive clues associated with a possible martian biological record, if any was every preserved, even if only as "chemical fossils."

  2. Applications of Surface Penetrating Radar for Mars Exploration

    Science.gov (United States)

    Li, H.; Li, C.; Ran, S.; Feng, J.; Zuo, W.

    2015-12-01

    Surface Penetrating Radar (SPR) is a geophysical method that uses electromagnetic field probe the interior structure and lithological variations of a lossy dielectric materials, it performs quite well in dry, icy and shallow-soil environments. The first radar sounding of the subsurface of planet was carried out by Apollo Lunar Sounder Experiment (ALSE) of the Apollo 17 in 1972. ALSE provided very precise information about the moon's topography and revealed structures beneath the surface in both Mare Crisium and Mare Serenitatis. Russian Mars'92 was the first Mars exploration mission that tried to use SPR to explore martian surface, subsurface and ionosphere. Although Mars'96 launch failed in 1996, Russia(Mars'98, cancelled in 1998; Phobos-Grunt, launch failed in 2011), ESA(Mars Express, succeeded in 2003; Netlander, cancelled in 2003; ExoMars 2018) and NASA(MRO, succeeded in 2005; MARS 2020) have been making great effects to send SPR to Mars, trying to search for the existence of groundwater and life in the past 20 years. So far, no Ground Penetrating Radar(GPR) has yet provided in situ observations on the surface of Mars. In December 2013, China's CE-3 lunar rover (Yuto) equipped with a GPR made the first direct measurement of the structure and depth of the lunar soil, and investigation of the lunar crust structure along the rover path. China's Mars Exploration Program also plans to carry the orbiting radar sounder and rover GPR to characterize the nature of subsurface water or ices and the layered structure of shallow subsurface of Mars. SPR can provide diversity of applications for Mars exploration , that are: to map the distribution of solid and liquid water in the upper portions of the Mars' crust; to characterize the subsurface geologic environment; to investigate the planet's subsurface to better understand the evolution and habitability of Mars; to perform the martain ionosphere sounding. Based on SPR's history and achievements, combined with the

  3. Human Exploration of Mars Design Reference Architecture 5.0

    Science.gov (United States)

    Drake, Bret G.

    2009-01-01

    This document reviews the Design Reference Architecture (DRA) for human exploration of Mars. The DRA represents the current best strategy for human missions. The DRA is not a formal plan, but provides a vision and context to tie current systems and technology developments to potential missions to Mars, and it also serves as a benchmark against which alternative architectures can be measured. The document also reviews the objectives and products of the 2007 study that was to update NASA's human Mars mission reference architecture, assess strategic linkages between lunar and Mars strategies, develop an understanding of methods for reducing cost/risk of human missions through investment in research, technology development and synergy with other exploration plans. There is also a review of the process by which the DRA will continue to be refined. The unique capacities of human exploration is reviewed. The possible goals and objectives of the first three human missions are presented, along with the recommendation that the mission involve a long stay visiting multiple sites.The deployment strategy is outlined and diagrammed including the pre-deployment of the many of the material requirements, and a six crew travel to Mars on a six month trajectory. The predeployment and the Orion crew vehicle are shown. The ground operations requirements are also explained. Also the use of resources found on the surface of Mars is postulated. The Mars surface exploration strategy is reviewed, including the planetary protection processes that are planned. Finally a listing of the key decisions and tenets is posed.

  4. Continuing the biological exploration of Mars

    Science.gov (United States)

    Klein, Harold P.

    1988-01-01

    Mars has been an object of interest for the better part of this century. To a biologist, Mars assumes special importance because many aspects of the theory of chemical evolution for the origin of life can be tested there. The central idea of this theory is that life on a suitable planet arises through a process in which the so-called biogenic elements combine to form increasingly more complex molecules under the influence of naturally-occurring energy sources ultimately resulting in the formation of replicating organic molecules. The biogenic elements are present on Mars today. Furthermore, the available evidence also strongly suggests that Mars may have had an early history similar to that of the Earth, including a period in which large amounts of liquid water once flowed on its surface and a denser atmosphere and higher global temperatures prevailed. This is important since many lines of evidence indicate that living organisms were already present on the Earth within the first billion years after its formation at a time when the environment on Mars may have closely resembled that of Earth. Our current knowledge of the state of chemical evolution on Mars can best be described as paradoxical. Most of what we have learned has come from experiments performed on the Viking landers. The combination of planned investigations covered a broad range of techniques to detect signs of chemical evolution. The most surprising data from all of these was the absence of any detectable quantities of organic compounds at the two landing sites. On the other hand, the Viking experiments did indicate that the Martian surface samples contained unidentified strong oxidant(s) that could account for their absence.

  5. Processing of Mars Exploration Rover Imagery for Science and Operations Planning

    Science.gov (United States)

    Alexander, Douglass A.; Deen, Robert G.; Andres, Paul M.; Zamani, Payam; Mortensen, Helen B.; Chen, Amy C.; Cayanan, Michael K.; Hall, Jeffrey R.; Klochko, Vadim S.; Pariser, Oleg; Stanley, Carol L.; Thompson, Charles K.; Yagi, Gary M.

    2006-01-01

    The twin Mars Exploration Rovers (MER) delivered an unprecedented array of image sensors to the Mars surface. These cameras were essential for operations, science, and public engagement. The Multimission Image Processing Laboratory (MIPL) at the Jet Propulsion Laboratory was responsible for the first-order processing of all of the images returned by these cameras. This processing included reconstruction of the original images, systematic and ad hoc generation of a wide variety of products derived from those images, and delivery of the data to a variety of customers, within tight time constraints. A combination of automated and manual processes was developed to meet these requirements, with significant inheritance from prior missions. This paper describes the image products generated by MIPL for MER and the processes used to produce and deliver them.

  6. Mud Volcanoes as Exploration Targets on Mars

    Science.gov (United States)

    Allen, Carlton C.; Oehler, Dorothy Z.

    2010-01-01

    Tens of thousands of high-albedo mounds occur across the southern part of the Acidalia impact basin on Mars. These structures have geologic, physical, mineralogic, and morphologic characteristics consistent with an origin from a sedimentary process similar to terrestrial mud volcanism. The potential for mud volcanism in the Northern Plains of Mars has been recognized for some time, with candidate mud volcanoes reported from Utopia, Isidis, northern Borealis, Scandia, and the Chryse-Acidalia region. We have proposed that the profusion of mounds in Acidalia is a consequence of this basin's unique geologic setting as the depocenter for the tune fraction of sediments delivered by the outflow channels from the highlands.

  7. Meteorites on Mars observed with Mars Exploration Rovers

    Science.gov (United States)

    Schroder, C.; Rodionov, D.S.; McCoy, T.J.; Jolliff, B.L.; Gellert, Ralf; Nittler, L.R.; Farrand, W. H.; Johnson, J. R.; Ruff, S.W.; Ashley, James W.; Mittlefehldt, D. W.; Herkenhoff, K. E.; Fleischer, I.; Haldemann, A.F.C.; Klingelhofer, G.; Ming, D. W.; Morris, R.V.; de Souza, P.A.; Squyres, S. W.; Weitz, C.; Yen, A. S.; Zipfel, J.; Economou, T.

    2008-01-01

    Reduced weathering rates due to the lack of liquid water and significantly greater typical surface ages should result in a higher density of meteorites on the surface of Mars compared to Earth. Several meteorites were identified among the rocks investigated during Opportunity's traverse across the sandy Meridiani plains. Heat Shield Rock is a IAB iron meteorite and has been officially recognized as 'Meridiani Planum.' Barberton is olivine-rich and contains metallic Fe in the form of kamacite, suggesting a meteoritic origin. It is chemically most consistent with a mesosiderite silicate clast. Santa Catarina is a brecciated rock with a chemical and mineralogical composition similar to Barberton. Barberton, Santa Catarina, and cobbles adjacent to Santa Catarina may be part of a strewn field. Spirit observed two probable iron meteorites from its Winter Haven location in the Columbia Hills in Gusev Crater. Chondrites have not been identified to date, which may be a result of their lower strengths and probability to survive impact at current atmospheric pressures. Impact craters directly associated with Heat Shield Rock, Barberton, or Santa Catarina have not been observed, but such craters could have been erased by eolian-driven erosion. Copyright 2008 by the American Geophysical Union.

  8. A Subsurface Explorer for Deep Underground Exploration on Mars

    Science.gov (United States)

    Wilcox, B. H.; Morgan, A. R.

    2000-08-01

    A subsurface explorer (SSX) is being developed at the Jet Propulsion Laboratory which is suitable for exploration of the deep underground environments on Mars. The device is a self-contained piledriver which uses a novel 'spinning hammer' technology to convert a small continuous power feed from the surface over a two-wire tether into a large rotational energy of a spinning mass. The rotational energy is converted to translational energy by a novel mechanism described here. The hammer blows propagate as shock waves through a nosepiece, pulverizing the medium ahead of the SSX. A small portion of the pulverized medium is returned to the surface through a hole liner extending behind the SSX. This tube is 'cast in place' from two chemical feedstocks which come down from the surface through passages in the hole liner and which are reacted together to produce new material with which to produce the hole liner. The lined hole does not need to be the full diameter of the SSX: approximately 100 kilograms of liner material can create a tunnel liner with a three millimeter inside diameter and a six millimeter outside diameter with at total length of four kilometers. Thus it is expected that core samples representing an overlapping set of three-millimeter diameter cores extending the entire length of the SSX traverse could be returned to the surface. A pneumatic prototype has been built which penetrated easily to the bottom of an eight meter vertical test facility. An electric prototype is now under construction. It is expected that the SSX will be able to penetrate through sand or mixed regolith, ice, permafrost, or solid rock, such as basalt. For pure or nearly pure ice applications, the device may be augmented with hot water jets to melt the ice and stir any sediment which may build up ahead of the vehicle. It is expected that an SSX approximately one meter long, three to four centimeters in diameter, and with a power budget of approximately 200 Watts will be able to explore

  9. Rover: Autonomous concepts for Mars exploration

    Science.gov (United States)

    Baiget, A.; Castets, B.; Chochon, H.; Hayard, M.; Lamarre, H.; Lamothe, A.

    1993-01-01

    The development of a mobile, autonomous vehicle that will be launched towards an unknown planet is considered. The rover significant constraints are: Ariane 5 compatibility, Earth/Mars transfer capability, 1000 km autonomous moving in Mars environment, on board localization, and maximum science capability. Two different types of subsystem were considered: classical subsystems (mechanical and mechanisms, thermal, telecommunications, power, onboard data processing) and robotics subsystem, (perception/navigation, autonomous displacement generation, autonomous localization). The needs of each subsystem were studied in terms of energy and data handling capability, in order to choose an on board architecture which best use the available capability, by means of specialized parts. A compromise must always be done between every subsystem in order to obtain the real need with respect to the goal, for example: between perception/navigation and the motion capability. A compromise must also be found between mechanical assembly and calibration need, which is a real problem.

  10. The NASA 2003 Mars Exploration Rover Panoramic Camera (Pancam) Investigation

    Science.gov (United States)

    Bell, J. F.; Squyres, S. W.; Herkenhoff, K. E.; Maki, J.; Schwochert, M.; Morris, R. V.; Athena Team

    2002-12-01

    The Panoramic Camera System (Pancam) is part of the Athena science payload to be launched to Mars in 2003 on NASA's twin Mars Exploration Rover missions. The Pancam imaging system on each rover consists of two major components: a pair of digital CCD cameras, and the Pancam Mast Assembly (PMA), which provides the azimuth and elevation actuation for the cameras as well as a 1.5 meter high vantage point from which to image. Pancam is a multispectral, stereoscopic, panoramic imaging system, with a field of regard provided by the PMA that extends across 360o of azimuth and from zenith to nadir, providing a complete view of the scene around the rover. Pancam utilizes two 1024x2048 Mitel frame transfer CCD detector arrays, each having a 1024x1024 active imaging area and 32 optional additional reference pixels per row for offset monitoring. Each array is combined with optics and a small filter wheel to become one "eye" of a multispectral, stereoscopic imaging system. The optics for both cameras consist of identical 3-element symmetrical lenses with an effective focal length of 42 mm and a focal ratio of f/20, yielding an IFOV of 0.28 mrad/pixel or a rectangular FOV of 16o\\x9D 16o per eye. The two eyes are separated by 30 cm horizontally and have a 1o toe-in to provide adequate parallax for stereo imaging. The cameras are boresighted with adjacent wide-field stereo Navigation Cameras, as well as with the Mini-TES instrument. The Pancam optical design is optimized for best focus at 3 meters range, and allows Pancam to maintain acceptable focus from infinity to within 1.5 meters of the rover, with a graceful degradation (defocus) at closer ranges. Each eye also contains a small 8-position filter wheel to allow multispectral sky imaging, direct Sun imaging, and surface mineralogic studies in the 400-1100 nm wavelength region. Pancam has been designed and calibrated to operate within specifications from -55oC to +5oC. An onboard calibration target and fiducial marks provide

  11. Earth Mars similarity criteria for exploring martian vehicles

    Science.gov (United States)

    Savu, G.

    2006-10-01

    In order to select the most efficient kind of a martian exploring vehicle, the similarity criteria are deduced from the equilibrium movement in the terrestrial and martian conditions. Different invariants have been obtained for the existing (entry capsules, parachutes and rovers) and potential martian exploring vehicles (lighter-than-air vehicle, airplane, helicopter and Mars Jumper). These similarity criteria, as non-dimensional numbers, allow to quickly compare if such kind of vehicles can operate in the martian environment, the movement performances, the necessary geometrical dimensions and the power consumption. Following this way of study it was concluded what vehicle is most suitable for the near soil Mars exploration. “Mars Rover” has less power consumption on Mars, but due to the rugged terrain the performances are weak. A vacuumed rigid airship is possible to fly with high performances and endurance on Mars, versus the impossibility of such a machine on the Earth. Due to very low density and the low Reynolds numbers in the Mars atmosphere, the power consumption for the martian airplane or helicopter is substantially higher. The most efficient vehicle for the Mars exploration seems to be a machine using the in situ non-chemical propellants: the 95% CO2 atmosphere and the weak solar radiation. A small compressor, electrically driven by photovoltaics, compresses the gas in a storage tank, in time. If the gas is expanded through a nozzle, sufficient lift and control forces are obtained for a VTOL flight of kilometers over the martian soil, in comparison with tens of meters of the actual Mars rovers.

  12. Earth-Mars similarity criteria for exploring martian vehicles

    Science.gov (United States)

    Savu, G.

    2003-11-01

    In order to select the most efficient kind of a martian exploring vehicle, the similarity criteria are deduced from the equilibrium movement in the terrestrial and martian conditions. Different invariants have been obtained for the existing (entry capsules, parachutes and rovers) and potential martian exploring vehicles (lighter-than-air vehicle, airplane, helicopter and Mars Jumper). These similarity criteria, as non dimensional numbers, allow to quickly compare if such a kind of vehicles can operate in the martian environment, the movement performances, the necessary geometrical dimensions and the power consumption. Following this way of study it was concluded what vehicle is most suitable for the near soil Mars exploration. "Mars Rover" has less power consumption on Mars, but due to the rugged terrain the performances are weak. A vacuumed rigid airship is possible to fly with high performances and endurance on Mars, versus the impossibility of such a machine on the Earth. Due to very low density and the low Reynolds numbers in the Mars atmosphere, the power consumption for the martian airplane or helicopter, is substantial higher. The most efficient vehicle for the Mars exploration it seems to be a machine using the in-situ non-chemical propellants: the 95% CO2 atmosphere and the weak solar radiation. A small compressor, electrically driven by photovoltaics, compresses the gas in a storage tank, in time. If the gas is expanded through a nozzle, sufficient lift and control forces are obtained for a VTOL flight of kilometers over the martian soil, in comparison with tens of meters of the actual Mars rovers.

  13. Automation and Robotics for Human Mars Exploration (AROMA)

    Science.gov (United States)

    Hofmann, Peter; von Richter, Andreas

    2003-01-01

    Automation and Robotics (A&R) systems are a key technology for Mars exploration. All over the world initiatives in this field aim at developing new A&R systems and technologies for planetary surface exploration. From December 2000 to February 2002 Kayser-Threde GmbH, Munich, Germany lead a study called AROMA (Automation and Robotics for Human Mars Exploration) under ESA contract in order to define a reference architecture of A&R elements in support of a human Mars exploration program. One of the goals of this effort is to initiate new developments and to maintain the competitiveness of European industry within this field. c2003 Published by Elsevier Science Ltd.

  14. Why Landers Should Explore Fresh, Small Craters on Mars

    Science.gov (United States)

    Kirkland, L. E.; Herr, K. C.; Adams, P. M.

    2008-03-01

    Small, fresh craters at the Nevada Test Site are unique, high quality test beds to develop exploration techniques for new craters spotted on Mars by Malin et al. The NTS craters provide data to determine the optimum crater size for exploration.

  15. Reaching Mars: multi-criteria R&D portfolio selection for Mars exploration technology planning

    Science.gov (United States)

    Smith, J. H.; Dolgin, B. P.; Weisbin, C. R.

    2003-01-01

    The exploration of Mars has been the focus of increasing scientific interest about the planet and its relationship to Earth. A multi-criteria decision-making approach was developed to address the question, Given a Mars program composed of mission concepts dependent on a variety of alternative technology development programs, which combination of technologies would enable missions to maximize science return under a constrained budget?.

  16. Medical System Concept of Operations for Mars Exploration Missions

    Science.gov (United States)

    Urbina, Michelle; Rubin, D.; Hailey, M.; Reyes, D.; Antonsen, Eric

    2017-01-01

    Future exploration missions will be the first time humanity travels beyond Low Earth Orbit (LEO) since the Apollo program, taking us to cis-lunar space, interplanetary space, and Mars. These long-duration missions will cover vast distances, severely constraining opportunities for emergency evacuation to Earth and cargo resupply opportunities. Communication delays and blackouts between the crew and Mission Control will eliminate reliable, real-time telemedicine consultations. As a result, compared to current LEO operations onboard the International Space Station, exploration mission medical care requires an integrated medical system that provides additional in-situ capabilities and a significant increase in crew autonomy. The Medical System Concept of Operations for Mars Exploration Missions illustrates how a future NASA Mars program could ensure appropriate medical care for the crew of this highly autonomous mission. This Concept of Operations document, when complete, will document all mission phases through a series of mission use case scenarios that illustrate required medical capabilities, enabling the NASA Human Research Program (HRP) Exploration Medical Capability (ExMC) Element to plan, design, and prototype an integrated medical system to support human exploration to Mars.

  17. Concept Maps Applied to Mars Exploration Public Outreach

    Science.gov (United States)

    Briggs, Geoffrey; Canas, Alberto; Shamma, David; Scargle, Jeffrey; Novak, Joseph

    2004-01-01

    This paper describes CMEX Mars, an effort in the creation of a comprehensive set of concept maps to describe all aspects of Mars exploration. These concept maps, created using the CmapTools software developed by the Institute for Human and Machine Cognition, are available on the Internet at http:/cmex.arc.nasa.gov/CMEX and are linked among themselves as well as to resources on the Internet. The work described took place mainly between 1998 and 2001 and combined the goals of: 1) developing a library of concept maps for educational outreach while also 2) refining the capabilities of the software used to create the interactive maps and 3) making them available on the Internet. Here we focus on the library of Mars exploration concept maps that has been created.

  18. Mars

    CERN Document Server

    Elkins-Tanton, Linda T

    2010-01-01

    Mars exploration has never been more active, and our understanding of the planet is advancing rapidly. New discoveries reveal gullies carved by recent groundwater flow, thick ice deposits protected by rocks and soil even at the equator, and new evidence for lakes and seas in Mars' past. The Martian surface has some of the oldest planetary crust in the solar system, containing clues to conditions in early planets that cannot be obtained elsewhere.Beginning with a discussion of Mars as a planet in orbit, Mars, Revised Edition covers fundamental facts about this planet, including its mass and siz

  19. Mars Exploration Using ELF Electromagnetic Measurements

    Science.gov (United States)

    Kozakiewicz, J.; Kulak, A.; Zietara, K.

    2015-12-01

    We present a methodology and instrumentation allowing for an investigation of the major environmental aspects of Mars, such as the structure of the planetary subsurface, and the presence of electrical discharges in the atmosphere. The methodology is based on the propagation of extremely low frequency (ELF) electromagnetic (EM) waves (3Hz-3kHz). These weakly attenuated waves, once generated by electrical discharges, propagate around a planet in a waveguide made of two electrically conductive spheres: the ground and the ionosphere. They are also capable of producing global EM resonances called Schumann resonances (SR). When an ELF wave is propagating from its source to a receiver, the environmental properties, such as: electrical conductivity of the waveguide boundaries, influence its propagation parameters. Using an analytical approach, we can estimate the structure of the planetary subsurface or the lower ionosphere layers on the basis of the measured parameters. As there is no liquid water at the Martian surface, the Martian low-conductivity ground enables deep ELF penetration into the planetary subsurface. As a result, the presented technique can be used as a tool to detect groundwater reservoirs located even several kilometers below the surface. On the basis of presently available date on the Martian subsurface, and theories of electrical properties of rocks, ice and water, we have developed probable Martian subsurface models with and without aquifers. The obtained results indicate that if aquifers are present beneath the Martian surface, the SR frequencies, the SR amplitudes, and the ELF phase velocities will be higher by about 12%, 37%, and 9%, respectively, as compare to the situation, in which there is solely a dry basaltic ground. As the presented phenomenon is of the global nature, one measuring station, located at the planetary surface, is enough to perform some basic research. The proposed lightweight measuring equipment, consisting of a low-power ELF

  20. Mars Exploration Rovers Launch Contingency Efforts

    Science.gov (United States)

    McGrath, Brian E.; Frostbutter, David A.; Parthasarathy, Karungulam N.; Heyler, Gene A.; Chang, Yale

    2004-02-01

    On 10 June 2003 at 1:58 p.m. Eastern Daylight Time (EDT) and 7 July 2003 at 11:18 p.m. EDT, two separate spacecraft/rovers were successfully launched to Mars atop a Delta II 7925 and Delta II 7925H, respectively. Each spacecraft/rover carried eight Light Weight Radioisotope Heater Units (LWRHUs) for thermal conditioning of electronics during the cold Martian nights. As a part of the joint National Aeronautics and Space Administration/U. S. Department of Energy safety effort, a contingency plan was prepared to address the unlikely events of an accidental suborbital reentry or out-of-orbit reentry. The objective of the contingency plan was to develop and implement procedures to predict, within the first hour, the probable Earth Impact Footprints (EIFs) for the LWRHUs or other possible spacecraft debris after an accidental reentry. No ablation burn-through of the heat sources' aeroshells was expected, as a result of earlier testing. Any predictions would be used in subsequent notification and recovery efforts. The Johns Hopkins University Applied Physics Laboratory, as part of a multi-agency team, was responsible for prediction of the EIFs, and the time of reentry from a potential orbital decay. The tools used to predict the EIFs included a Three-Degree-of-Freedom (3DOF) trajectory simulation code, a Six-Degree-of-Freedom (6DOF) code, a database of aerodynamic coefficients for the LWRHUs and other spacecraft debris, secure links to obtain tracking data, and a high fidelity special perturbation orbit integrator code to predict time of spacecraft reentry from orbital decay. This paper will discuss the contingency plan and process, as well as highlight the improvements made to the analytical tools. Improvements to the 3DOF, aerodynamic database, and orbit integrator and inclusion of the 6DOF have significantly enhanced the prediction capabilities. In the days before launch, the trajectory simulation codes were exercised and predictions of hypothetical EIFs were produced

  1. Conventional vs Biomimetic Approaches to the Exploration of Mars

    Science.gov (United States)

    Ellery, A.

    It is not usual to refer to convention in planetary exploration missions by virtue of the innovation required for such projects. The term conventional refers to the methodologies, tools and approaches typically adopted in engineering that are applied to such missions. Presented is a "conventional" Mars rover mission in which the author was involved - ExoMars - into which is interspersed references to examples where biomimetic approaches may yield superior capabilities. Biomimetics is a relatively recently active area of research which seeks to examine how biological systems solve the problem of survival in the natural environment. Biological organisms are autonomous entities that must survive in a hostile world adapting both adaptivity and robustness. It is not then surprising that biomimetics is particularly useful when applied to robotic elements of a Mars exploration mission. I present a number of areas in which biomimetics may yield new solutions to the problem of Mars exploration - optic flow navigation, potential field navigation, genetically-evolved neuro-controllers, legged locomotion, electric motors implementing muscular behaviour, and a biomimetic drill based on the wood wasp ovipositor. Each of these techniques offers an alternative approach to conventional ones. However, the perceptive hurdles are likely to dwarf the technical hurdles in implementing many of these methods in the near future.

  2. MISSION PROFILE AND DESIGN CHALLENGES FOR MARS LANDING EXPLORATION

    Directory of Open Access Journals (Sweden)

    J. Dong

    2017-07-01

    Full Text Available An orbiter and a descent module will be delivered to Mars in the Chinese first Mars exploration mission. The descent module is composed of a landing platform and a rover. The module will be released into the atmosphere by the orbiter and make a controlled landing on Martian surface. After landing, the rover will egress from the platform to start its science mission. The rover payloads mainly include the subsurface radar, terrain camera, multispectral camera, magnetometer, anemometer to achieve the scientific investigation of the terrain, soil characteristics, material composition, magnetic field, atmosphere, etc. The landing process is divided into three phases (entry phase, parachute descent phase and powered descent phase, which are full of risks. There exit lots of indefinite parameters and design constrain to affect the selection of the landing sites and phase switch (mortaring the parachute, separating the heat shield and cutting off the parachute. A number of new technologies (disk-gap-band parachute, guidance and navigation, etc. need to be developed. Mars and Earth have gravity and atmosphere conditions that are significantly different from one another. Meaningful environmental conditions cannot be recreated terrestrially on earth. A full-scale flight validation on earth is difficult. Therefore the end-to-end simulation and some critical subsystem test must be considered instead. The challenges above and the corresponding design solutions are introduced in this paper, which can provide reference for the Mars exploration mission.

  3. Mars-Moons Exploration, Reconnaissance and Landed Investigation (MERLIN)

    Science.gov (United States)

    Murchie, S. L.; Chabot, N. L.; Buczkowski, D.; Arvidson, R. E.; Castillo, J. C.; Peplowski, P. N.; Ernst, C. M.; Rivkin, A.; Eng, D.; Chmielewski, A. B.; Maki, J.; trebi-Ollenu, A.; Ehlmann, B. L.; Spence, H. E.; Horanyi, M.; Klingelhoefer, G.; Christian, J. A.

    2015-12-01

    The Mars-Moons Exploration, Reconnaissance and Landed Investigation (MERLIN) is a NASA Discovery mission proposal to explore the moons of Mars. Previous Mars-focused spacecraft have raised fundamental questions about Mars' moons: What are their origins and compositions? Why do the moons resemble primitive outer solar system D-type objects? How do geologic processes modify their surfaces? MERLIN answers these questions through a combination of orbital and landed measurements, beginning with reconnaissance of Deimos and investigation of the hypothesized Martian dust belts. Orbital reconnaissance of Phobos occurs, followed by low flyovers to characterize a landing site. MERLIN lands on Phobos, conducting a 90-day investigation. Radiation measurements are acquired throughout all mission phases. Phobos' size and mass provide a low-risk landing environment: controlled descent is so slow that the landing is rehearsed, but gravity is high enough that surface operations do not require anchoring. Existing imaging of Phobos reveals low regional slope regions suitable for landing, and provides knowledge for planning orbital and landed investigations. The payload leverages past NASA investments. Orbital imaging is accomplished by a dual multispectral/high-resolution imager rebuilt from MESSENGER/MDIS. Mars' dust environment is measured by the refurbished engineering model of LADEE/LDEX, and the radiation environment by the flight spare of LRO/CRaTER. The landed workspace is characterized by a color stereo imager updated from MER/HazCam. MERLIN's arm deploys landed instrumentation using proven designs from MER, Phoenix, and MSL. Elemental measurements are acquired by a modified version of Rosetta/APXS, and an uncooled gamma-ray spectrometer. Mineralogical measurements are acquired by a microscopic imaging spectrometer developed under MatISSE. MERLIN delivers seminal science traceable to NASA's Strategic Goals and Objectives, Science Plan, and the Decadal Survey. MERLIN's science

  4. ISRU in the Context of Future European Human Mars Exploration

    Science.gov (United States)

    Baker, A. M.; Tomatis, C.

    2002-01-01

    ISRU or In-Situ Resource Utilisation is the use of Martian resources to manufacture, typically, life support consumables (e.g. water, oxygen, breathing buffer gases), and propellant for a return journey to Earth. European studies have shown that some 4kg of reaction mass must be launched to LEO to send 1kg payload to Mars orbit, with landing on the Mars surface reducing payload mass still further. This results in very high transportation costs to Mars, and still higher costs for returning payloads to Earth. There is therefore a major incentive to reduce payload mass for any form of Mars return mission (human or otherwise) by generating consumables on the surface. ESA through its GSTP programme has been investigating the system level design of a number of mission elements as potential European contributions to an international human Mars exploration mission intended for the 2020-2030 timeframe. One of these is an ISRU plant, a small chemical factory to convert feedstock brought from Earth (hydrogen), and Martian atmospheric gases (CO2 and trace quantities of nitrogen and argon) into methane and oxygen propellant for Earth return and life support consumables, in advance of the arrival of astronauts. ISRU technology has been the subject of much investigation around the world, but little detailed research or system level studies have been reported in Europe. Furthermore, the potential applicability of European expertise, technology and sub- system studies to Martian ISRU is not well quantified. Study work covered in this paper has compared existing designs (e.g. NASA's Design Reference Mission, DLR and Mars Society studies) with the latest ESA derived requirements for human Mars exploration, and has generated a system level ISRU design. This paper will review and quantify the baseline chemical reactions essential for ISRU, including CO2 collection and purification, Sabatier reduction of CO2 with hydrogen to methane and water, and electrolysis of water in the context of

  5. Astrobiology, Mars Exploration and Lassen Volcanic National Park

    Science.gov (United States)

    Des Marais, David J.

    2015-01-01

    The search for evidence of life beyond Earth illustrates how the charters of NASA and the National Park Service share common ground. The mission of NPS is to preserve unimpaired the natural and cultural resources of the National Park System for the enjoyment, education and inspiration of this and future generations. NASA's Astrobiology program seeks to understand the origins, evolution and distribution of life in the universe, and it abides by the principles of planetary stewardship, public outreach, and education. We cannot subject planetary exploration destinations to Earthly biological contamination both for ethical reasons and to preserve their scientific value for astrobiology. We respond to the public's interest in the mysteries of life and the cosmos by honoring their desire to participate in the process of discovery. We involve youth in order to motivate career choices in science and technology and to perpetuate space exploration. The search for evidence of past life on Mars illustrates how the missions of NASA and NPS can become synergistic. Volcanic activity occurs on all rocky planets in our Solar System and beyond, and it frequently interacts with water to create hydrothermal systems. On Earth these systems are oases for microbial life. The Mars Exploration Rover Spirit has found evidence of extinct hydrothermal system in Gusev crater, Mars. Lassen Volcanic National Park provides a pristine laboratory for investigating how microorganisms can both thrive and leave evidence of their former presence in hydrothermal systems. NASA scientists, NPS interpretation personnel and teachers can collaborate on field-oriented programs that enhance Mars mission planning, engage students and the public in science and technology, and emphasize the ethics of responsible exploration.

  6. Mars Exobiology: The Principles Behind The Plan For Exploration

    Science.gov (United States)

    DesMarais, D. J.; DeVincenzi, Donald L.; Carr, M. H.; Clark, B. C.; Farmer, J. D.; Hayes, J. M.; Holland, H.; Kerridge, J. F.; Klein, H. P.; McDonald, G. D.

    1995-01-01

    The search for evidence of life on Mars is a highly interdisciplinary enterprise which extends beyond the traditional life sciences. Mars conceivably had a pervasive ancient biosphere which may have persisted even to the present, but only in subsurface environments. Understanding the history of Mars' global environment, including its inventory of volatile elements, is a crucial part of the search strategy. Those deposits (minerals, sediments, etc.) which could have and retained a record of earlier biological activity must be identified and examined. While the importance of. seeking another biosphere has not diminished during the years since the Viking mission, the strategy for Mars exploration certainly has been modified by later discoveries. The Viking mission itself demonstrated that the present day surface environment of Mars is hostile to life as we know it. Thus, to search effectively for life on Mars, be it extant or extinct, we now must greatly improve our understanding of Mars the planet. Such an understanding will help us broaden our search beyond the Viking lander sites, both back in time to earlier epochs and elsewhere to other sites and beneath the surface. Exobiology involves much more than simply a search for extant life beyond Earth. It addresses the prospect of long-extinct biospheres and also the chemistry, organic and otherwise, which either led to life or which occurred on rocky planets that remained lifeless. Even a Mars without a biosphere would reveal much about life. How better to understand the origin and impact of a biosphere than to compare Earth with another similar but lifeless planet? Still, several relatively recent discoveries offer encouragement that a Martian biosphere indeed might have existed. The ancient Martian surface was extensively sculptured by volcanism and the activity of liquid water. Such observations invoke impressions of an ancient martian atmosphere and environment that resembled ancient Earth more than present

  7. Mars Aeronomy Explorer (MAX): Study Employing Distributed Micro-Spacecraft

    Science.gov (United States)

    Shotwell, Robert F.; Gray, Andrew A.; Illsley, Peter M.; Johnson, M.; Sherwood, Robert L.; Vozoff, M.; Ziemer, John K.

    2005-01-01

    An overview of a Mars Aeronomy Explorer (MAX) mission design study performed at NASA's Jet Propulsion Laboratory is presented herein. The mission design consists of ten micro-spacecraft orbiters launched on a Delta IV to Mars polar orbit to determine the spatial, diurnal and seasonal variation of the constituents of the Martian upper atmosphere and ionosphere over the course of one Martian year. The spacecraft are designed to allow penetration of the upper atmosphere to at least 90 km. This property coupled with orbit precession will yield knowledge of the nature of the solar wind interaction with Mars, the influence of the Mars crustal magnetic field on ionospheric processes, and the measurement of present thermal and nonthermal escape rates of atmospheric constituents. The mission design incorporates alternative design paradigms that are more appropriate for-and in some cases motivate-distributed micro-spacecraft. These design paradigms are not defined by a simple set of rules, but rather a way of thinking about the function of instruments, mission reliability/risk, and cost in a systemic framework.

  8. A Vision for the Exploration of Mars: Robotic Precursors Followed by Humans to Mars Orbit in 2033

    Science.gov (United States)

    Sellers, Piers J.; Garvin, James B.; Kinney, Anne L.; Amato, Michael J.; White, Nicholas E.

    2012-01-01

    The reformulation of the Mars program gives NASA a rare opportunity to deliver a credible vision in which humans, robots, and advancements in information technology combine to open the deep space frontier to Mars. There is a broad challenge in the reformulation of the Mars exploration program that truly sets the stage for: 'a strategic collaboration between the Science Mission Directorate (SMD), the Human Exploration and Operations Mission Directorate (HEOMD) and the Office of the Chief Technologist, for the next several decades of exploring Mars'.Any strategy that links all three challenge areas listed into a true long term strategic program necessitates discussion. NASA's SMD and HEOMD should accept the President's challenge and vision by developing an integrated program that will enable a human expedition to Mars orbit in 2033 with the goal of returning samples suitable for addressing the question of whether life exists or ever existed on Mars

  9. Carl Sagan and the Exploration of Mars and Venus

    Science.gov (United States)

    Toon, Owen B.; Condon, Estelle P. (Technical Monitor)

    1997-01-01

    Inspired by childhood readings of books by Edgar Rice Burroughs, Carl Sagan's first interest in planetary science focused on Mars and Venus. Typical of much of his career he was skeptical of early views about these planets. Early in this century it was thought that the Martian wave of darkening, a seasonal albedo change on the planet, was biological in origin. He suggested instead that it was due to massive dust storms, as was later shown to be the case. He was the first to recognize that Mars has huge topography gradients across its surface. During the spacecraft era, as ancient river valleys were found on the planet, he directed studies of Mars' ancient climate. He suggested that changes in the planets orbit were involved in climate shifts on Mars, just as they are on Earth. Carl had an early interest in Venus. Contradictory observations led to a controversy about the surface temperature, and Carl was one of the first to recognize that Venus has a massive greenhouse effect at work warming its surface. His work on radiative transfer led to an algorithm that was extensively used by modelers of the Earth's climate and whose derivatives still dominate the calculation of radiative transfer in planetary atmospheres today. Carl inspired a vast number of young scientists through his enthusiasm for new ideas and discoveries, his skeptical approach, and his boundless energy. I had the privilege to work in Carl's laboratory during the peak of the era of Mars' initial exploration. It was an exciting time, and place. Carl made it a wonderful experience.

  10. Exploring the Co-Development of Reading Fluency and Reading Comprehension: A Twin Study

    Science.gov (United States)

    Little, Callie W.; Hart, Sara A.; Quinn, Jamie M.; Tucker-Drob, Elliot M.; Taylor, Jeanette; Schatschneider, Christopher

    2017-01-01

    This study explores the co-development of two related but separate reading skills, reading fluency and reading comprehension, across Grades 1-4. A bivariate biometric dual change score model was applied to longitudinal data collected from 1,784 twin pairs between the ages of 6 and 10 years. Grade 1 skills were influenced by highly overlapping…

  11. Human Space Exploration: The Moon, Mars, and Beyond

    Science.gov (United States)

    Sexton, Jeffrey D.

    2007-01-01

    America is returning to the Moon in preparation for the first human footprint on Mars, guided by the U.S. Vision for Space Exploration. This presentation will discuss NASA's mission, the reasons for returning to the Moon and going to Mars, and how NASA will accomplish that mission in ways that promote leadership in space and economic expansion on the new frontier. The primary goals of the Vision for Space Exploration are to finish the International Space Station, retire the Space Shuttle, and build the new spacecraft needed, to return people to the Moon and go to Mars. The Vision commits NASA and the nation to an agenda of exploration that also includes robotic exploration and technology development, while building on lessons learned over 50 years of hard-won experience. Why the Moon? Many questions about the Moon's potential resources and how its history is linked to that of Earth were spurred by the brief Apollo explorations of the 1960s and 1970s. This new venture will carry more explorers to more diverse landing sites with more capable tools and equipment for extended expeditions. The Moon also will serve as a training ground before embarking on the longer, more difficult trip to Mars. NASA plans to build a lunar outpost at one of the lunar poles, learn to live off the land, and reduce dePendence on Earth for longer missions. America needs to extend its ability to survive in hostile environments close to our home planet before astronauts will reach Mars, a planet very much like Earth. NASA has worked with scientists to define lunar exploration goals and is addressing the opportunities for a range of scientific study on Mars. In order to reach the Moon and Mars within a lifetime and within budget, NASA is building on common hardware, shared knowledge, and unique experience derived from the Apollo Saturn, Space Shuttle and contemporary commercial launch vehicle programs. The journeys to the Moon and Mars will require a variety of vehicles, including the Ares I

  12. (Nearly) Seven Years on Mars: Adventure, Adversity, and Achievements with the NASA Mars Exploration Rovers Spirit and Opportunity

    Science.gov (United States)

    Bell, J. F.; Mars Exploration Rover Science; Engineering Teams

    2010-12-01

    NASA successfully landed twin rovers, Spirit and Opportunity, on Mars in January 2004, in the most ambitious mission of robotic exploration attempted to that time. Each rover is outfitted as a robot field geologist with an impressive array of scientific instruments--cameras, spectrometers, other sensors--designed to investigate the composition and geologic history of two distinctly-different landing sites. The sites were chosen because of their potential to reveal clues about the past history of water and climate on Mars, and thus to provide tests of the hypothesis that the planet may once have been an abode for life. In this presentation I will review the images, spectra, and chemical/mineralogic information that the rover team has been acquiring from the landing sites and along the rovers' 7.7 and 22.7 km traverse paths, respectively. The data and interpretations have been widely shared with the public and the scientific community through web sites, frequent press releases, and scientific publications, and they provide quantitative evidence that liquid water has played a role in the modification of the Martian surface during the earliest part of the planet's history. At the Spirit site in Gusev Crater, the role of water appears to have been relatively minor in general, although the recent discovery of enigmatic hydrated sulfate salt and amorphous silica deposits suggests that locally there may have been significant water-rock interactions, and perhaps even sustained hydrothermal activity. At the Opportunity site in Meridiani Planum, geologic and mineralogic evidence suggests that liquid water was stable at the surface and shallow subsurface for significant periods of early Martian geologic history. An exciting implication from both missions is that localized environments on early Mars may have been "habitable" by some terrestrial standards. As of early September 2010, the rovers had operated for 2210 and 2347 Martian days (sols), respectively, with the Spirit

  13. Russian Nuclear Rocket Engine Design for Mars Exploration

    Institute of Scientific and Technical Information of China (English)

    Vadim Zakirov; Vladimir Pavshook

    2007-01-01

    This paper is to promote investigation into the nuclear rocket engine (NRE) propulsion option that is considered as a key technology for manned Mars exploration. Russian NRE developed since the 1950 s in the former Soviet Union to a full-scale prototype by the 1990 s is viewed as advantageous and the most suitable starting point concept for manned Mars mission application study. The main features of Russian heterogeneous core NRE design are described and the most valuable experimental performance results are summarized. These results have demonstrated the significant specific impulse performance advantage of the NRE over conventional liquid rocket engine (LRE) propulsion technologies. Based on past experience,the recent developments in the field of high-temperature nuclear fuels, and the latest conceptual studies, the developed NRE concept is suggested to be upgraded to the nuclear power and propulsion system (NPPS),more suitable for future manned Mars missions. Although the NRE still needs development for space application, the problems are solvable with additional effort and funding.

  14. Exploration of Victoria crater by the mars rover opportunity

    Science.gov (United States)

    Squyres, S. W.; Knoll, A.H.; Arvidson, R. E.; Ashley, James W.; Bell, J.F.; Calvin, W.M.; Christensen, P.R.; Clark, B. C.; Cohen, B. A.; De Souza, P.A.; Edgar, L.; Farrand, W. H.; Fleischer, I.; Gellert, Ralf; Golombek, M.P.; Grant, J.; Grotzinger, J.; Hayes, A.; Herkenhoff, K. E.; Johnson, J. R.; Jolliff, B.; Klingelhofer, G.; Knudson, A.; Li, R.; McCoy, T.J.; McLennan, S.M.; Ming, D. W.; Mittlefehldt, D. W.; Morris, R.V.; Rice, J. W.; Schroder, C.; Sullivan, R.J.; Yen, A.; Yingst, R.A.

    2009-01-01

    The Mars rover Opportunity has explored Victoria crater, a ???750-meter eroded impact crater formed in sulfate-rich sedimentary rocks. Impact-related stratigraphy is preserved in the crater walls, and meteoritic debris is present near the crater rim. The size of hematite-rich concretions decreases up-section, documenting variation in the intensity of groundwater processes. Layering in the crater walls preserves evidence of ancient wind-blown dunes. Compositional variations with depth mimic those ???6 kilometers to the north and demonstrate that water-induced alteration at Meridiani Planum was regional in scope.

  15. Visual Target Tracking on the Mars Exploration Rovers

    Science.gov (United States)

    Kim, Won; Biesiadecki, Jeffrey; Ali, Khaled

    2008-01-01

    Visual target tracking (VTT) software has been incorporated into Release 9.2 of the Mars Exploration Rover (MER) flight software, now running aboard the rovers Spirit and Opportunity. In the VTT operation (see figure), the rover is driven in short steps between stops and, at each stop, still images are acquired by actively aimed navigation cameras (navcams) on a mast on the rover (see artistic rendition). The VTT software processes the digitized navcam images so as to track a target reliably and to make it possible to approach the target accurately to within a few centimeters over a 10-m traverse.

  16. The Interplanetary Internet: A Communications Infrastructure for Mars Exploration

    Science.gov (United States)

    Burleigh, S.; Cerf, V.; Durst, R.; Fall, K.; Hooke, A.; Scott, K.; Weiss, H.

    2002-01-01

    A successful program of Mars Exploration will depend heavily on a robust and dependable space communications infrastructure that is well integrated with the terrestrial Internet. In the same way that the underpinnings of the Internet are the standardized "TCP/IP" suite of protocols, an "Interplanetary Internet" will need a similar set of capabilities that can support reliable communications across vast distances and highly stressed communications environments. For the past twenty years, the Consultative Committee for Space Data Systems (CCSDS) has been developing standardized long- haul space link communications techniques that are now in use by over two hundred missions within the international space community. New CCSDS developments, shortly to be infused into Mars missions, include a proximity link standard and a store-and- forward file transfer protocol. As part of its `Next Generation Internet' initiative, the U.S. Defense Advanced Projects Agency (DARPA) recently supported an architectural study of a future "InterPlaNetary Internet" (IPN). The IPN architecture assumes that in short-delay environments - such as on and around Mars - standard Internet technologies will be adapted to the locally harsh environment and deployed within surface vehicles and orbiting relays. A long-haul interplanetary backbone network that includes Deep Space Network (DSN) gateways into the terrestrial Internet will interconnect these distributed internets that are scattered across the Solar System. Just as TCP/IP unites the Earth's "network of networks" to become the Internet, a new suite of protocols known as "Bundling" will enable the IPN to become a "network of internets" to support true interplanetary dialog. An InterPlaNetary Internet Research Group has been established within the Internet community to coordinate this research and NASA has begun to support the further development of the IPN architecture and the Bundling protocols. A strategy is being developed whereby the

  17. Nuclear thermal propulsion transportation systems for lunar/Mars exploration

    Science.gov (United States)

    Clark, John S.; Borowski, Stanley K.; Mcilwain, Melvin C.; Pellaccio, Dennis G.

    1992-01-01

    Nuclear thermal propulsion technology development is underway at NASA and DoE for Space Exploration Initiative (SEI) missions to Mars, with initial near-earth flights to validate flight readiness. Several reactor concepts are being considered for these missions, and important selection criteria will be evaluated before final selection of a system. These criteria include: safety and reliability, technical risk, cost, and performance, in that order. Of the concepts evaluated to date, the Nuclear Engine for Rocket Vehicle Applications (NERVA) derivative (NDR) is the only concept that has demonstrated full power, life, and performance in actual reactor tests. Other concepts will require significant design work and must demonstrate proof-of-concept. Technical risk, and hence, development cost should therefore be lowest for the concept, and the NDR concept is currently being considered for the initial SEI missions. As lighter weight, higher performance systems are developed and validated, including appropriate safety and astronaut-rating requirements, they will be considered to support future SEI application. A space transportation system using a modular nuclear thermal rocket (NTR) system for lunar and Mars missions is expected to result in significant life cycle cost savings. Finally, several key issues remain for NTR's, including public acceptance and operational issues. Nonetheless, NTR's are believed to be the 'next generation' of space propulsion systems - the key to space exploration.

  18. The State and Future of Mars Polar Science and Exploration

    Science.gov (United States)

    Clifford, S.M.; Crisp, D.; Fisher, D.A.; Herkenhoff, K. E.; Smrekar, S.E.; Thomas, P.C.; Wynn-Williams, D. D.; Zurek, R.W.; Barnes, J.R.; Bills, B.G.; Blake, E.W.; Calvin, W.M.; Cameron, J.M.; Carr, M.H.; Christensen, P.R.; Clark, B. C.; Clow, G.D.; Cutts, J.A.; Dahl-Jensen, D.; Durham, W.B.; Fanale, F.P.; Farmer, J.D.; Forget, F.; Gotto-Azuma, K.; Grard, R.; Haberle, R.M.; Harrison, W.; Harvey, R.; Howard, A.D.; Ingersoll, A.P.; James, P.B.; Kargel, J.S.; Kieffer, H.H.; Larsen, J.; Lepper, K.; Malin, M.C.; McCleese, D.J.; Murray, B.; Nye, J.F.; Paige, D.A.; Platt, S.R.; Plaut, J.J.; Reeh, N.; Rice, J.W.; Smith, D.E.; Stoker, C.R.; Tanaka, K.L.; Mosley-Thompson, E.; Thorsteinsson, T.; Wood, S.E.; Zent, A.; Zuber, M.T.; Zwally, H.J.

    2000-01-01

    As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ???106 km2 and total as much as 3-4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young - preserving a record of the seasonal and climatic cycling of atmospheric CO2, H2O, and dust over the past ???105-108 years. For this reason, the martian polar deposits may serve as a Rosetta Stone for understanding the geologic and climatic history of the planet - documenting variations in insolation (due to quasiperiodic oscillations in the planet's obliquity and orbital elements), volatile mass balance, atmospheric composition, dust storm activity, volcanic eruptions, large impacts, catastrophic floods, solar luminosity, supernovae, and perhaps even a record of microbial life. Beyond their scientific value, the polar regions may soon prove important for another reason - providing a valuable and accessible reservoir of water to support the long-term human exploration of Mars. In this paper we assess the current state of Mars polar research, identify the key questions that motivate the exploration of the polar regions, discuss the extent to which current missions will address these questions, and speculate about what additional capabilities and investigations may be required to address the issues that remain outstanding. ?? 2000 Academic Press.

  19. Slip Validation and Prediction for Mars Exploration Rovers

    Directory of Open Access Journals (Sweden)

    Jeng Yen

    2008-04-01

    Full Text Available This paper presents a novel technique to validate and predict the rover slips on Martian surface for NASA’s Mars Exploration Rover mission (MER. Different from the traditional approach, the proposed method uses the actual velocity profile of the wheels and the digital elevation map (DEM from the stereo images of the terrain to formulate the equations of motion. The six wheel speed from the empirical encoder data comprises the vehicle's velocity, and the rover motion can be estimated using mixed differential and algebraic equations. Applying the discretization operator to these equations, the full kinematics state of the rover is then resolved by the configuration kinematics solution in the Rover Sequencing and Visualization Program (RSVP. This method, with the proper wheel slip and sliding factors, produces accurate simulation of the Mars Exploration rovers, which have been validated with the earth-testing vehicle. This computational technique has been deployed to the operation of the MER rovers in the extended mission period. Particularly, it yields high quality prediction of the rover motion on high slope areas. The simulated path of the rovers has been validated using the telemetry from the onboard Visual Odometry (VisOdom. Preliminary results indicate that the proposed simulation is very effective in planning the path of the rovers on the high-slope areas.

  20. Photogrammetric processing of rover imagery of the 2003 Mars Exploration Rover mission

    Science.gov (United States)

    Di, Kaichang; Xu, Fengliang; Wang, Jue; Agarwal, Sanchit; Brodyagina, Evgenia; Li, Rongxing; Matthies, Larry

    In the 2003 Mars Exploration Rover (MER) mission, the twin rovers, Spirit and Opportunity, carry identical Athena instrument payloads and engineering cameras for exploration of the Gusev Crater and Meridiani Planum landing sites. This paper presents the photogrammetric processing techniques for high accuracy topographic mapping and rover localization at the two landing sites. Detailed discussions about camera models, reference frames, interest point matching, automatic tie point selection, image network construction, incremental bundle adjustment, and topographic product generation are given. The developed rover localization method demonstrated the capability of correcting position errors caused by wheel slippages, azimuthal angle drift and other navigation errors. A comparison was also made between the bundle-adjusted rover traverse and the rover track imaged from the orbit. Mapping products including digital terrain models, orthophotos, and rover traverse maps have been generated for over two years of operations, and disseminated to scientists and engineers of the mission through a web-based GIS. The maps and localization information have been extensively used to support tactical operations and strategic planning of the mission.

  1. A mars communication constellation for human exploration and network science

    Science.gov (United States)

    Castellini, Francesco; Simonetto, Andrea; Martini, Roberto; Lavagna, Michèle

    2010-01-01

    This paper analyses the possibility of exploiting a small spacecrafts constellation around Mars to ensure a complete and continuous coverage of the planet, for the purpose of supporting future human and robotic operations and taking advantage of optical transmission techniques. The study foresees such a communications mission to be implemented at least after 2020 and a high data-rate requirement is imposed for the return of huge scientific data from massive robotic exploration or to allow video transmissions from a possible human outpost. In addition, the set-up of a communication constellation around Mars would give the opportunity of exploiting this multi-platform infrastructure to perform network science, that would largely increase our knowledge of the planet. The paper covers all technical aspects of a feasibility study performed for the primary communications mission. Results are presented for the system trade-offs, including communication architecture, constellation configuration and transfer strategy, and the mission analysis optimization, performed through the application of a multi-objective genetic algorithm to two models of increasing difficulty for the low-thrust trajectory definition. The resulting communication architecture is quite complex and includes six 530 kg spacecrafts on two different orbital planes, plus one redundant unit per plane, that ensure complete coverage of the planet’s surface; communications between the satellites and Earth are achieved through optical links, that allow lower mass and power consumption with respect to traditional radio-frequency technology, while inter-satellite links and spacecrafts-to-Mars connections are ensured by radio transmissions. The resulting data-rates for Earth-Mars uplink and downlink, satellite-to-satellite and satellite-to-surface are respectively 13.7 Mbps, 10.2 Mbps, 4.8 Mbps and 4.3 Mbps, in worst-case. Two electric propulsion modules are foreseen, to be placed on a C3˜0 escape orbit with two

  2. Exploring Mars for Evidence of Habitable Environments and Life

    Science.gov (United States)

    DesMarais, David J.

    2014-01-01

    The climate of Mars has been more similar to that of Earth than has the climate of any other planet in our Solar System. But Mars still provides a valuable alternative example of how planetary processes and environments can affect the potential presence of life elsewhere. For example, although Mars also differentiated very early into a core, mantle and crust, it then evolved mostly if not completely without plate tectonics and has lost most of its early atmosphere. The Martian crust has been more stable than that of Earth, thus it has probably preserved a more complete record of its earliest history. Orbital observations determined that near-surface water was once pervasive. Orbiters have identified the following diverse aqueous sedimentary deposits: layered phyllosilicates, phyllosilicates in intracrater fans, plains sediments potentially harboring evaporitic minerals, deep phyllosilicates, carbonate-bearing deposits, intracrater clay-sulfate deposits, Meridiani-type layered deposits, valles-type layered deposits, hydrated silica-bearing deposits, and gypsum plains. These features, together with evidence of more vigorous past geologic activity, indicate that early climates were wetter and perhaps also somewhat warmer. The denser atmosphere that was required for liquid water to be stable on the surface also provided more substantial protection from radiation. Whereas ancient climates might have favored habitable environments at least in some localities, clearly much of the Martian surface for most of its history has been markedly less favorable for life. The combination of dry conditions, oxidizing surface environments and typically low rates of sedimentation are not conducive to the preservation of evidence of ancient environments and any biota. Thus a strategy is required whereby candidate sites are first identified and then characterized for their potential to preserve evidence of past habitable environments. Rovers are then sent to explore the most promising

  3. Dual-Use Ballute-Based Robust Aerocapture, EDL, and Surface Exploration Architecture for Effective and Distributed Exploration of Mars

    Science.gov (United States)

    Saikia, S. J.; Longuski, J. M.

    2012-06-01

    An innovative and game-changing Mars exploration mission architecture by synergizing the advantages of Inflatable Aerodynamic Decelerators, and a network of miniature space-based, aerial, surface, & subsurface exploration elements.

  4. Autonomous Navigation Results from the Mars Exploration Rover (MER) Mission

    Science.gov (United States)

    Maimone, Mark; Johnson, Andrew; Cheng, Yang; Willson, Reg; Matthies, Larry H.

    2004-01-01

    In January, 2004, the Mars Exploration Rover (MER) mission landed two rovers, Spirit and Opportunity, on the surface of Mars. Several autonomous navigation capabilities were employed in space for the first time in this mission. ]n the Entry, Descent, and Landing (EDL) phase, both landers used a vision system called the, Descent Image Motion Estimation System (DIMES) to estimate horizontal velocity during the last 2000 meters (m) of descent, by tracking features on the ground with a downlooking camera, in order to control retro-rocket firing to reduce horizontal velocity before impact. During surface operations, the rovers navigate autonomously using stereo vision for local terrain mapping and a local, reactive planning algorithm called Grid-based Estimation of Surface Traversability Applied to Local Terrain (GESTALT) for obstacle avoidance. ]n areas of high slip, stereo vision-based visual odometry has been used to estimate rover motion, As of mid-June, Spirit had traversed 3405 m, of which 1253 m were done autonomously; Opportunity had traversed 1264 m, of which 224 m were autonomous. These results have contributed substantially to the success of the mission and paved the way for increased levels of autonomy in future missions.

  5. Nuclear Safety Analysis for the Mars Exploration Rover 2003 Project

    Science.gov (United States)

    Firstenberg, Henry; Rutger, Lyle L.; Mukunda, Meera; Bartram, Bart W.

    2004-02-01

    The National Aeronautics and Space Administration's Mars Exploration Rover (MER) 2003 project is designed to place two mobile laboratories (Rovers) on Mars to remotely characterize a diversity of rocks and soils. Milestones accomplished so far include two successful launches of identical spacecraft (the MER-A and MER-B missions) from Cape Canaveral Air Force Station, Florida on June 10 and July 7, 2003. Each Rover uses eight Light Weight Radioisotope Heater Units (LWRHUs) fueled with plutonium-238 dioxide to provide local heating of Rover components. The LWRHUs are provided by the U.S. Department of Energy. In addition, small quantities of radioactive materials in sealed sources are used in scientific instrumentation on the Rover. Due to the radioactive nature of these materials and the potential for accidents, a formal Launch Approval Process requires the preparation of a Final Safety Analysis Report (FSAR) for submittal to and independent review by an Interagency Nuclear Safety Review Panel. This paper presents a summary of the FSAR in terms of potential accident scenarios, probabilities, source terms, radiological consequences, mission risks, and uncertainties in the reported results.

  6. Economical Mars Exploration Supported by a Nuclear Thermal Rocket

    Science.gov (United States)

    Howe, S. D.; O'Brien, R. C.

    2012-06-01

    A nuclear thermal rocket (NTR) developed for human Mars missions could act as a "mother ship" and carry multiple unmanned platforms to Mars for independent deployment. Use of the NTR could increase the science per dollar for each Earth launch.

  7. Robotic Arm and Rover Actuator Systems for Mars Exploration

    Science.gov (United States)

    Reid, L.; Brawn, D.; Noon, D.

    1999-01-01

    Missions such as the Sojourner Rover, the Robotic Arm for Mars Polar Lander, and the 2003 Mars Rover, Athena, use numerous actuators that must operate reliably in extreme environments for long periods of time.

  8. The Interplanetary Internet: a communications infrastructure for Mars exploration

    Science.gov (United States)

    Burleigh, Scott; Cerf, Vinton; Durst, Robert; Fall, Kevin; Hooke, Adrian; Scott, Keith; Weiss, Howard

    2003-01-01

    A strategy is being developed whereby the current set of internationally standardized space data communications protocols can be incrementally evolved so that a first version of an operational "Interplanetary Internet" is feasible by the end of the decade. This paper describes its architectural concepts, discusses the current set of standard space data communications capabilities that exist to support Mars exploration and reviews proposed new developments. We also speculate that these current capabilities can grow to support future scenarios where human intelligence is widely distributed across the Solar System and day-to-day communications dialog between planets is routine. c2003 American Institute of Aeronautics and Astronautics. Published by Elsevier Science Ltd. All rights reserved.

  9. The Interplanetary Internet: a communications infrastructure for Mars exploration

    Science.gov (United States)

    Burleigh, Scott; Cerf, Vinton; Durst, Robert; Fall, Kevin; Hooke, Adrian; Scott, Keith; Weiss, Howard

    2003-01-01

    A strategy is being developed whereby the current set of internationally standardized space data communications protocols can be incrementally evolved so that a first version of an operational "Interplanetary Internet" is feasible by the end of the decade. This paper describes its architectural concepts, discusses the current set of standard space data communications capabilities that exist to support Mars exploration and reviews proposed new developments. We also speculate that these current capabilities can grow to support future scenarios where human intelligence is widely distributed across the Solar System and day-to-day communications dialog between planets is routine. c2003 American Institute of Aeronautics and Astronautics. Published by Elsevier Science Ltd. All rights reserved.

  10. Results of the Mars Exploration Rover Athena science investigation

    Science.gov (United States)

    Squyres, S. W.; Athena Science Team

    2004-05-01

    The Mars Exploration Rovers ``Spirit" and ``Opportunity" have performed missions of scientific exploration at Gusev Crater and Meridiani Planum on Mars. Their objective is to search for evidence of water activity at the two sites, and to assess the past habitability of the sites. The Gusev Crater site investigated by Spirit is a flat, rock-strewn plain. All rocks at the site investigated to date are olivine basalt. The rover has conducted a radial traverse through the ejecta blanket of the crater Bonneville. After investigation of this crater, the rover will continue its traverse toward the Columbia Hills, a range of hills over 100 m high approximately 2.5 km to the west. To date, no unambiguous evidence of aqueous activity has been found at the Gusev site. The lander carrying Opportunity came to rest in a 20-meter crater in Meridiani Planum. Exposed within this crater is a small outcrop of bedrock. The bedrock outcrop has been studied in detail, and shows compelling evidence for formation and alteration processes involving liquid water. This evidence includes (a) embedded hematite-rich spherules that appear to be concretions, (b) tabular voids with characteristics consistent with those of molds of crystals formed by precipitation from water, (c) extremely high sulfur content, suggesting a compositon of 30-40 salts by weight, (d) significant quantities of jarosite, (e) Cl/Br systematics similar to those of terrestrial evaporites, and (f) cross stratification indicative of deposition in a moving fluid environment, probably water. Precipitated minerals at the Meridiani site could be very effective at preserving evidence of conditions and processes in the aqueous environment there, making them an attractive potential target for future study.

  11. Exploring Anxiety Symptoms in a Large-Scale Twin Study of Children with Autism Spectrum Disorders, Their Co-Twins and Controls

    Science.gov (United States)

    Hallett, Victoria; Ronald, Angelica; Colvert, Emma; Ames, Catherine; Woodhouse, Emma; Lietz, Stephanie; Garnett, Tracy; Gillan, Nicola; Rijsdijk, Fruhling; Scahill, Lawrence; Bolton, Patrick; Happé, Francesca

    2013-01-01

    Background: Although many children with autism spectrum disorders (ASDs) experience difficulties with anxiety, the manifestation of these difficulties remains unresolved. The current study assessed anxiety in a large population-based twin sample, aged 10-15 years. Phenotypic analyses were used to explore anxiety symptoms in children with ASDs,…

  12. Assessment of Mars Exploration Rover Landing Site Predictions

    Science.gov (United States)

    Golombek, M. P.

    2005-05-01

    Comprehensive analyses of remote sensing data during the 3-year effort to select the Mars Exploration Rover landing sites at Gusev crater and Meridiani Planum correctly predicted the safe and trafficable surfaces explored by the two rovers. Gusev crater was predicted to be a relatively low relief surface that was comparably dusty, but less rocky than the Viking landing sites. Available data for Meridiani Planum indicated a very flat plain composed of basaltic sand to granules and hematite that would look completely unlike any of the existing landing sites with a dark, low albedo surface, little dust and very few rocks. Orbital thermal inertia measurements of 315 J m-2 s-0.5 K-1 at Gusev suggested surfaces dominated by duricrust to cemented soil-like materials or cohesionless sand or granules, which is consistent with observed soil characteristics and measured thermal inertias from the surface. THEMIS thermal inertias along the traverse at Gusev vary from 285 at the landing site to 330 around Bonneville rim and show systematic variations that can be related to the observed increase in rock abundance (5-30%). Meridiani has an orbital bulk inertia of ~200, similar to measured surface inertias that correspond to observed surfaces dominated by 0.2 mm sand size particles. Rock abundance derived from orbital thermal differencing techniques suggested that Meridiani Planum would have very low rock abundance, consistent with the rock free plain traversed by Opportunity. Spirit landed in an 8% orbital rock abundance pixel, consistent with the measured 7% of the surface covered by rocks >0.04 m diameter at the landing site, which is representative of the plains away from craters. The orbital albedo of the Spirit traverse varies from 0.19 to 0.30, consistent with surface measurements in and out of dust devil tracks. Opportunity is the first landing in a low albedo portion of Mars as seen from orbit, which is consistent with the dark, dust-free surface and measured albedos. The

  13. Extraterrestrial Moessbauer spectroscopy: more than 3 years of Mars exploration and developments for future missions

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Christian, E-mail: christian.schroeder-1@nasa.gov [NASA Johnson Space Center, Astromaterials Research and Exploration Science, Mail Code KR (United States); Klingelhoefer, Goestar, E-mail: klingel@mail.uni-mainz.de [Johannes Gutenberg-Universitaet, Institut fuer Anorganische und Analytische Chemie (Germany); Morris, Richard V., E-mail: richard.v.morris@nasa.gov [NASA Johnson Space Center, Astromaterials Research and Exploration Science, Mail Code KR (United States); Rodionov, Daniel S., E-mail: rodionov@iki.rssi.ru; Fleischer, Iris, E-mail: fleischi@uni-mainz.de; Blumers, Mathias, E-mail: mblumers@uni-mainz.de [Johannes Gutenberg-Universitaet, Institut fuer Anorganische und Analytische Chemie (Germany)

    2008-02-15

    After almost 4 years of operating on the surface of Mars, Moessbauer spectroscopy has become a mature technique for robotic planetary exploration. The combination of quantitative information about the distribution of Fe among its oxidation and coordination states, identification of Fe-bearing phases, and relative distribution of Fe among those phases provides valuable contributions to the search for past water activity, the assessment of past environmental conditions, and the suitability for life of the two NASA Mars Exploration Rover landing sites. Experience from the Mars Exploration Rover Mission highlights needs for improvement of the instruments for future missions such as the Russian Phobos-Grunt and the European ExoMars rover.

  14. Human exploration and settlement of Mars - The roles of humans and robots

    Science.gov (United States)

    Duke, Michael B.

    1991-01-01

    The scientific objectives and strategies for human settlement on Mars are examined in the context of the Space Exploration Initiative (SEI). An integrated strategy for humans and robots in the exploration and settlement of Mars is examined. Such an effort would feature robotic, telerobotic, and human-supervised robotic phases.

  15. Accessing Information on the Mars Exploration Rovers Mission

    Science.gov (United States)

    Walton, J. D.; Schreiner, J. A.

    2005-12-01

    In January 2004, the Mars Exploration Rovers (MER) mission successfully deployed two robotic geologists - Spirit and Opportunity - to opposite sides of the red planet. Onboard each rover is an array of cameras and scientific instruments that send data back to Earth, where ground-based systems process and store the information. During the height of the mission, a team of about 250 scientists and engineers worked around the clock to analyze the collected data, determine a strategy and activities for the next day and then carefully compose the command sequences that would instruct the rovers in how to perform their tasks. The scientists and engineers had to work closely together to balance the science objectives with the engineering constraints so that the mission achieved its goals safely and quickly. To accomplish this coordinated effort, they adhered to a tightly orchestrated schedule of meetings and processes. To keep on time, it was critical that all team members were aware of what was happening, knew how much time they had to complete their tasks, and could easily access the information they need to do their jobs. Computer scientists and software engineers at NASA Ames Research Center worked closely with the mission managers at the Jet Propulsion Laboratory (JPL) to create applications that support the mission. One such application, the Collaborative Information Portal (CIP), helps mission personnel perform their daily tasks, whether they work inside mission control or the science areas at JPL, or in their homes, schools, or offices. With a three-tiered, service-oriented architecture (SOA) - client, middleware, and data repository - built using Java and commercial software, CIP provides secure access to mission schedules and to data and images transmitted from the Mars rovers. This services-based approach proved highly effective for building distributed, flexible applications, and is forming the basis for the design of future mission software systems. Almost two

  16. Recurring Slope Lineae and Future Exploration of Mars

    Science.gov (United States)

    McEwen, Alfred; Byrne, Shane; Chevrier, Vincent; Chojnacki, Matt; Dundas, Colin; Masse, Marion; Mattson, Sarah; Ojha, Lujendra; Pommerol, Antoine; Toigo, Anthony; Wray, James

    2014-05-01

    Recurring slope lineae (RSL) on Mars may be evidence for the seasonal flow or seepage of water on relatively warm slopes. RSL are narrow (250 K to >300 K. Over the past Martian year we have monitored active RSL in equatorial (0°-15°S) regions of Mars, especially in the deep canyons of Valles Marineris [McEwen et al., 2014, Nature Geoscience]. These equatorial RSL are especially active on north-facing slopes in northern summer and spring and on south-facing slopes in southern spring and summer, following the most normal solar incidence angles on these steep slopes. More recently we have confirmed RSL near 35°N in the low-albedo and low-altitude Acidalia Planitia. All RSL locations have warm peak daily temperatures (typically >273 K at the surface) in the seasons when RSL are active, and occur on steep, rocky, low-albedo slopes. However, most times and places with these properties lack apparent RSL, so there are additional, unseen requirements. We do not know what time of day RSL are actively flowing. Seasonal variation in the atmospheric column abundance of water vapor does not match the RSL activity. Seasonal melting of shallow ice best explains the RSL observations, but the origin and replenishment of such ice is not understood, especially in the tropics. Laboratory experiments are consistent with two key MRO observations: (1) that seeping water darkens basaltic soils but may only produce weak water absorption bands undetectable in ratio spectra after partial dehydration during the low-humidity middle afternoon conditions when MRO observes; and (2) the flows are more linear than under terrestrial conditions and do not erode channels under Martian atmospheric pressures [Masse et al., 2014, LPSC]. No dry process is known to create such slowly creeping seasonal flows. The potential for equatorial water activity creates new exploration opportunities, to search for extant life, as well as challenges such as the definition of special regions for planetary protection.

  17. Acid Sulfate Weathering on Mars: Results from the Mars Exploration Rover Mission

    Science.gov (United States)

    Ming, Douglas W.; Morris, R. V.; Golden, D. C.

    2006-01-01

    Sulfur has played a major role in the formation and alteration of outcrops, rocks, and soils at the Mars Exploration Rover landing sites on Meridiani Planum and in Gusev crater. Jarosite, hematite, and evaporite sulfates (e.g., Mg and Ca sulfates) occur along with siliciclastic sediments in outcrops at Meridiani Planum. The occurrence of jarosite is a strong indicator for an acid sulfate weathering environment at Meridiani Planum. Some outcrops and rocks in the Columbia Hills in Gusev crater appear to be extensively altered as suggested by their relative softness as compared to crater floor basalts, high Fe(3+)/FeT, iron mineralogy dominated by nanophase Fe(3+) oxides, hematite and/or goethite, corundum-normative mineralogies, and the presence of Mg- and Casulfates. One scenario for aqueous alteration of these rocks and outcrops is that vapors and/or fluids rich in SO2 (volcanic source) and water interacted with rocks that were basaltic in bulk composition. Ferric-, Mg-, and Ca-sulfates, phosphates, and amorphous Si occur in several high albedo soils disturbed by the rover's wheels in the Columbia Hills. The mineralogy of these materials suggests the movement of liquid water within the host material and the subsequent evaporation of solutions rich in Fe, Mg, Ca, S, P, and Si. The presence of ferric sulfates suggests that these phases precipitated from highly oxidized, low-pH solutions. Several hypotheses that invoke acid sulfate weathering environments have been suggested for the aqueous formation of sulfate-bearing phases on the surface of Mars including (1) the oxidative weathering of ultramafic igneous rocks containing sulfides; (2) sulfuric acid weathering of basaltic materials by solutions enriched by volcanic gases (e.g., SO2); and (3) acid fog (i.e., vapors rich in H2SO4) weathering of basaltic or basaltic-derived materials.

  18. Exploring the Co-Development of Reading Fluency and Reading Comprehension: A Twin Study.

    Science.gov (United States)

    Little, Callie W; Hart, Sara A; Quinn, Jamie M; Tucker-Drob, Elliot M; Taylor, Jeanette; Schatschneider, Christopher

    2016-11-10

    This study explores the co-development of two related but separate reading skills, reading fluency and reading comprehension, across Grades 1-4. A bivariate biometric dual change score model was applied to longitudinal data collected from 1,784 twin pairs between the ages of 6 and 10 years. Grade 1 skills were influenced by highly overlapping genetic and environmental factors. Growth in both skills was influenced by highly overlapping shared environmental factors. Cross-lagged parameters indicated bidirectional effects, with stronger effects from fluency to comprehension change than from comprehension to fluency change.

  19. Advanced Communication and Networking Technologies for Mars Exploration

    Science.gov (United States)

    Bhasin, Kul; Hayden, Jeff; Agre, Jonathan R.; Clare, Loren P.; Yan, Tsun-Yee

    2001-01-01

    Next-generation Mars communications networks will provide communications and navigation services to a wide variety of Mars science vehicles including: spacecraft that are arriving at Mars, spacecraft that are entering and descending in the Mars atmosphere, scientific orbiter spacecraft, spacecraft that return Mars samples to Earth, landers, rovers, aerobots, airplanes, and sensing pods. In the current architecture plans, the communication services will be provided using capabilities deployed on the science vehicles as well as dedicated communication satellites that will together make up the Mars network. This network will evolve as additional vehicles arrive, depart or end their useful missions. Cost savings and increased reliability will result from the ability to share communication services between missions. This paper discusses the basic architecture that is needed to support the Mars Communications Network part of NASA's Space Science Enterprise (SSE) communications architecture. The network may use various networking technologies such as those employed in the terrestrial Internet, as well as special purpose deep-space protocols to move data and commands autonomously between vehicles, at disparate Mars vicinity sites (on the surface or in near-Mars space) and between Mars vehicles and earthbound users. The architecture of the spacecraft on-board local communications is being reconsidered in light of these new networking requirements. The trend towards increasingly autonomous operation of the spacecraft is aimed at reducing the dependence on resource scheduling provided by Earth-based operators and increasing system fault tolerance. However, these benefits will result in increased communication and software development requirements. As a result, the envisioned Mars communications infrastructure requires both hardware and protocol technology advancements. This paper will describe a number of the critical technology needs and some of the ongoing research

  20. Mars Exploration Rover mobility and robotic arm operational performance

    Science.gov (United States)

    Tunstel, Edward; Maimone, Mark; Trebi-Ollennu, Ashitey; Yen, Jeng; Petras, Richard; Wilson, Reg

    2005-01-01

    The purpose of this paper is to describe an actual instance of a practical human-robot system used on a NASA Mars rover mission that has been underway since January 2004 involving daily intercation between humans on Earth and mobile robots on Mars.

  1. New approaches to the exploration: planet Mars and bacterial life

    CERN Document Server

    Galletta, Giuseppe; D'Alessandro, Maurizio

    2011-01-01

    Planet Mars past environmental conditions were similar to the early Earth, but nowadays they are similar to those of a very cold desert, irradiated by intense solar UV light. However, some terrestrial lifeform showed the capability to adapt to very harsh environments, similar to the extreme condition of the Red Planet. In addition, recent discoveries of water in the Martian permafrost and of methane in the Martian atmosphere, have generated optimism regarding a potentially active subsurface Mars' biosphere. These findings increase the possibility of finding traces of life on a planet like Mars. However, before landing on Mars with dedicated biological experiments, it is necessary to understand the possibilities of finding life in the present Martian conditions. Finding a lifeform able to survive in Martian environment conditions may have a double meaning: increasing the hope of discovering extraterrestrial life and defining the limits for a terrestrial contamination of planet Mars. In this paper we present th...

  2. Improved Path Planning Onboard the Mars Exploration Rovers

    Science.gov (United States)

    Stentz, Anthony; Ferguson, David; Carsten, Joseph; Rankin, Arturo

    2007-01-01

    A revised version of the AutoNav (autonomous navigation with hazard avoidance) software running onboard each Mars Exploration Rover (MER) affords better obstacle avoidance than does the previous version. Both versions include GESTALT (Grid-based Estimation of Surface Traversability Applied to Local Terrain), a navigation program that generates local-terrain models from stereoscopic image pairs captured by onboard rover cameras; uses this information to evaluate candidate arcs that extend across the terrain from the current rover location; ranks the arcs with respect to hazard avoidance, minimization of steering time, and the direction towards the goal; and combines the rankings in a weighted vote to select an arc, along which the rover is then driven. GESTALT works well in navigating around small isolated obstacles, but tends to fail when the goal is on the other side of a large obstacle or multiple closely spaced small obstacles. When that occurs, the goal seeking votes and hazard avoidance votes conflict severely. The hazard avoidance votes will not allow the rover to drive through the unsafe area, and the waypoint votes will not allow enough deviation from the straight-line path for the rover to get around the hazard. The rover becomes stuck and is unable to reach the goal. The revised version of AutoNav utilizes a global path-planning program, Field D*, to evaluate the cost of traveling from the end of each GESTALT arc to the goal. In the voting process, Field D* arc votes supplant GESTALT goal-seeking arc votes. Hazard avoidance, steering bias, and Field D* votes are merged and the rover is driven a preset distance along the arc with the highest vote. Then new images are acquired and the process as described is repeated until the goal is reached. This new technology allows the rovers to autonomously navigate around much more complex obstacle arrangements than was previously possible. In addition, this improved autonomy enables longer traverses per Sol (a day

  3. Scientific Goals and Objectives for the Human Exploration of Mars: 1. Biology and Atmosphere/Climate

    Science.gov (United States)

    Levine, Joel S.; Garvin, J. B.; Anbar, A. D.; Beaty, D. W.; Bell, M. S.; Clancy, R. T.; Cockell, C. S.; Connerney, J. E.; Doran, P. T.; Delory, G.; Dickson, J. T.; Elphic, R. C.; Eppler, D. B.; Fernandez-Remolar, D. C.; Head, J. W.; Helper, M.; Gruener, J. E.; Heldmann, J.; Hipkin, V.; Lane, M. D.; Levy, J.; Moersch, J.; Ori, G. G.; Peach, L.; Poulet, F.

    2008-01-01

    To prepare for the exploration of Mars by humans, as outlined in the new national vision for Space Exploration (VSE), the Mars Exploration Program Analysis Group (MEPAG), chartered by NASA's Mars Exploration Program (MEP), formed a Human Exploration of Mars Science Analysis Group (HEM-SAG), in March 2007. HEM-SAG was chartered to develop the scientific goals and objectives for the human exploration of Mars based on the Mars Scientific Goals, Objectives, Investigations, and Priorities.1 The HEM-SAG is one of several humans to Mars scientific, engineering and mission architecture studies chartered in 2007 to support NASA s plans for the human exploration of Mars. The HEM-SAG is composed of about 30 Mars scientists representing the disciplines of Mars biology, climate/atmosphere, geology and geophysics from the U.S., Canada, England, France, Italy and Spain. MEPAG selected Drs. James B. Garvin (NASA Goddard Space Flight Center) and Joel S. Levine (NASA Langley Research Center) to serve as HEMSAG co-chairs. The HEM-SAG team conducted 20 telecons and convened three face-to-face meetings from March through October 2007. The management of MEP and MEPAG were briefed on the HEM-SAG interim findings in May. The HEM-SAG final report was presented on-line to the full MEPAG membership and was presented at the MEPAG meeting on February 20-21, 2008. This presentation will outline the HEM-SAG biology and climate/atmosphere goals and objectives. A companion paper will outline the HEM-SAG geology and geophysics goals and objectives.

  4. RAT magnet experiment on the Mars Exploration Rovers: Spirit and Opportunity beyond sol 500

    DEFF Research Database (Denmark)

    Leer, Kristoffer; Goetz, Walter; Chan, Marjorie A.;

    2011-01-01

    The Rock Abrasion Tool (RAT) magnet experiment on the Mars Exploration Rovers was designed to collect dust from rocks ground by the RAT of the two rovers on the surface of Mars. The dust collected on the magnets is now a mixture of dust from many grindings. Here the new data from the experiment a...

  5. Next-Generation Laser Retroreflectors for the Science and Exploration of the Moon, Mars and Beyond

    Science.gov (United States)

    Dell'Agnello, S.; SCF Lab Team; Currie, D.; Richards, R.; Chandler, J.

    2016-10-01

    We describe next-generation laser retroreflectors for solar system science/exploration, developed at INFN-LNF, Frascati, Italy in collaboration with ASI and NASA-SSERVI, for lunar missions, ExoMars, Mars2020, Phobos, Jupiter icy/rocky moons, asteroids.

  6. The Mars Exploration Rover Surface Mobility Flight Software: Driving Ambition

    Science.gov (United States)

    Biesiadecki, Jeffrey J.; Maimone, Mark W.

    2006-01-01

    In this paper we describe the software that has driven these rovers more than a combined 11,000 meters over the Martian surface, including its design and implementation, and summarize current mobility performance results from Mars.

  7. Low-Frequency Electromagnetic Exploration for Groundwater on Mars

    Science.gov (United States)

    Grimm, Robert E.

    2002-01-01

    Water with even a small amount of dissolved solids has an electrical conductivity orders of magnitude higher than dry rock and is therefore a near-ideal exploration target on Mars for low frequency, diffusive electromagnetic methods. Models of the temperature- and frequency-dependent electrical properties of rock-ice-water mixtures are used to predict the electromagnetic response of the Martian subsurface. Detection of ice is difficult unless it is massively segregated. In contrast, liquid water profoundly affects soundings, and even a small amount of adsorbed water in the cryosphere can be detected. Subcryospheric water is readily distinguishable at frequencies as low as 100 Hz for fresh water to 10 mHz for brines. These responses can be measured using either natural or artificial sources. Ultra low frequency signals from solar wind and diurnal-heating perturbations of the ionosphere are likely, and disturbances of regional crustal magnetic fields may also be observable. Spherics, or extremely to very low frequency signals from lightning discharge, would provide optimal soundings; however, lightning may be the least likely of the possible natural sources. Among the active techniques, only the time-domain electromagnetic (TDEM) method can accommodate a closely spaced transmitter and receiver and sound to depths of hundreds of meters or more. A ground- or aircraft-based TDEM system of several kilograms can detect water to a depth of several hundred meters, and a system of tens of kilograms featuring a large, fixed, rover- or ballistically deployed loop can detect water to several kilometers depth.

  8. A Human Exploration Zone on the East Rim of Hellas Basin, Mars: Mesopotamia

    Science.gov (United States)

    Gallegos, Z. E.; Newsom, H. E.

    2015-10-01

    This abstract highlights a previously unexplored area in the Hellas Planitia region of Mars. The exploration zone proposed offers scientifically compelling regions of interest, as well as abundant resources for reoccurring human missions.

  9. Storyboard for the Medical System Concept of Operations for Mars Exploration Missions

    Science.gov (United States)

    Antonsen, Eric; Hailey, Melinda; Reyes, David; Rubin, David; Urbina, Michelle

    2017-01-01

    This storyboard conceptualizes one scenario of an integrated medical system during a Mars exploration mission. All content is for illustrative purposes only and neither defines nor implies system design requirement.

  10. Drilling and Automation for Mars Exploration - 3rd Field Test on Devon Island

    Science.gov (United States)

    Zacny, K.; Paulsen, G.; Davis, K.; Glass, B.

    2007-03-01

    The third Drilling Automation for Mars Exploration field test took place inside the Haughton Crater on Devon Island in the Canadian High Arctic in July 2006. This season's objective was to demonstrate autonomous drilling capabilities while drilling with a

  11. Solar Power System Evaluated for the Human Exploration of Mars

    Science.gov (United States)

    Kerslake, Thomas W.

    2000-01-01

    The electric power system is a crucial element of any mission for the human exploration of the Martian surface. The bulk of the power generated will be delivered to crew life support systems, extravehicular activity suits, robotic vehicles, and predeployed in situ resource utilization (ISRU) equipment. In one mission scenario, before the crew departs for Mars, the ISRU plant operates for 435 days producing liquefied methane and oxygen for ascent-stage propellants and water for crew life support. About 200 days after ISRU production is completed, the crew arrives for a 500-day surface stay. In this scenario, the power system must operate for a total of 1130 days (equivalent to 1100 Martian "sols"), providing 400 MW-hr of energy to the ISRU plant and up to 18 kW of daytime user power. A photovoltaic power-generation system with regenerative fuel cell (RFC) energy storage has been under study at the NASA Glenn Research Center at Lewis Field. The conceptual power system is dominated by the 4000- m2 class photovoltaic array that is deployed orthogonally as four tent structures, each approximately 5 m on a side and 100-m long. The structures are composed of composite members deployed by an articulating mast, an inflatable boom, or rover vehicles, and are subsequently anchored to the ground. Array panels consist of thin polymer membranes with thin-film solar cells. The array is divided into eight independent electrical sections with solar cell strings operating at 600 V. Energy storage is provided by regenerative fuel cells based on hydrogen-oxygen proton exchange membrane technology. Hydrogen and oxygen reactants are stored in gaseous form at 3000 psi, and the water produced is stored at 14.7 psi. The fuel cell operating temperature is maintained by a 40-m2 deployable pumped-fluid loop radiator that uses water as the working fluid. The power management and distribution (PMAD) architecture features eight independent, regulated 600-Vdc channels. Power management and

  12. The European space exploration programme: current status of ESA's plans for Moon and Mars exploration.

    Science.gov (United States)

    Messina, Piero; Vennemann, Dietrich

    2005-01-01

    After a large consultation with the scientific and industrial communities in Europe, the Aurora Space Exploration Programme was unanimously approved at the European Space Agency (ESA) Council at ministerial level in Edinburgh in 2001. This marked the start of the programme's preparation phase that was due to finish by the end of 2004. Aurora features technology development robotic and crewed rehearsal missions aimed at preparing a human mission to Mars by 2033. Due to the evolving context, both international and European, ESA has undertaken a review of the goals and approach of its exploration programme. While maintaining the main robotic missions that had been conceived during Aurora, the European Space Exploration Programme that is currently being proposed to the Aurora participating states and other ESA Member States has a reviewed approach and will feature a greater synergy with other ESA programmes. The paper will present the process that led to the revision of ESA's plans in the field of exploration and will give the current status of the programme.

  13. Human missions to Mars enabling technologies for exploring the red planet

    CERN Document Server

    Rapp, Donald

    2016-01-01

    A mission to send humans to explore the surface of Mars has been the ultimate goal of planetary exploration since the 1950s, when von Braun conjectured a flotilla of 10 interplanetary vessels carrying a crew of at least 70 humans. Since then, more than 1,000 studies were carried out on human missions to Mars, but after 60 years of study, we remain in the early planning stages. The second edition of this book now includes an annotated history of Mars mission studies, with quantitative data wherever possible. Retained from the first edition, Donald Rapp looks at human missions to Mars from an engineering perspective. He divides the mission into a number of stages: Earth’s surface to low-Earth orbit (LEO); departing from LEO toward Mars; Mars orbit insertion and entry, descent and landing; ascent from Mars; trans-Earth injection from Mars orbit and Earth return. For each segment, he analyzes requirements for candidate technologies. In this connection, he discusses the status and potential of a wide range of el...

  14. United States Human Access to Space, Exploration of the Moon and Preparation for Mars Exploration

    Science.gov (United States)

    Rhatigan, Jennifer L.

    2009-01-01

    In the past, men like Leonardo da Vinci and Jules Verne imagined the future and envisioned fantastic inventions such as winged flying machines, submarines, and parachutes, and posited human adventures like transoceanic flight and journeys to the Moon. Today, many of their ideas are reality and form the basis for our modern world. While individual visionaries like da Vinci and Verne are remembered for the accuracy of their predictions, today entire nations are involved in the process of envisioning and defining the future development of mankind, both on and beyond the Earth itself. Recently, Russian, European, and Chinese teams have all announced plans for developing their own next generation human space vehicles. The Chinese have announced their intention to conduct human lunar exploration, and have flown three crewed space missions since 2003, including a flight with three crew members to test their extravehicular (spacewalking) capabilities in September 2008. Very soon, the prestige, economic development, scientific discovery, and strategic security advantage historically associated with leadership in space exploration and exploitation may no longer be the undisputed province of the United States. Much like the sponsors of the seafaring explorers of da Vinci's age, we are motivated by the opportunity to obtain new knowledge and new resources for the growth and development of our own civilization. NASA's new Constellation Program, established in 2005, is tasked with maintaining the United States leadership in space, exploring the Moon, creating a sustained human lunar presence, and eventually extending human operations to Mars and beyond. Through 2008, the Constellation Program developed a full set of detailed program requirements and is now completing the preliminary design phase for the new Orion Crew Exploration Vehicle (CEV), the Ares I Crew Launch Vehicle, and the associated infrastructure necessary for humans to explore the Moon. Component testing is well

  15. The Mars Hopper: a radioisotope powered, impulse driven, long-range, long-lived mobile platform for exploration of Mars

    Energy Technology Data Exchange (ETDEWEB)

    Steven D. Howe; Robert C. O' Brien; William Taitano; Doug Crawford; Nathan Jerred; Spencer Cooley; John Crapeau; Steve Hansen; Andrew Klein; James Werner

    2011-02-01

    Planetary exploration mission requirements are becoming more demanding. Due to the increasing cost, the missions that provide mobile platforms that can acquire data at multiple locations are becoming more attractive. Wheeled vehicles such as the MER rovers have proven extremely capable but have very limited range and cannot traverse rugged terrain. Flying vehicles such as balloons and airplanes have been proposed but are problematic due to the very thin atmospheric pressure and the strong, dusty winds present on Mars. The Center for Space Nuclear Research has designed an instrumented platform that can acquire detailed data at hundreds of locations during its lifetime - a Mars Hopper. The Mars Hopper concept utilizes energy from radioisotopic decay in a manner different from any existing radioisotopic power sources—as a thermal capacitor. By accumulating the heat from radioisotopic decay for long periods, the power of the source can be dramatically increased for short periods. The platform will be able to "hop" from one location to the next every 5-7 days with a separation of 5-10 km per hop. Preliminary designs show a platform that weighs around 52 kgs unfueled which is the condition at deployment. Consequently, several platforms may be deployed on a single launch from Earth. With sufficient lifetime, the entire surface of Mars can be mapped in detail by a couple dozen platforms. In addition, Hoppers can collect samples from all over the planet, including gorges, mountains and crevasses, and deliver them to a central location for eventual pick-up by a Mars Sample Return mission. The status of the Mars Hopper development project at the CSNR is discussed.

  16. The Exploration of Mars and the Improvement of Living Conditions in Western Asian Countries

    Science.gov (United States)

    De Morais Mendonca Teles, Antonio

    2016-07-01

    Space is the new frontier. The exploration of a new world, Mars, has been giving people on Earth valuable comparative information about climatic and geological processes occurring here on our home planet. With the Viking 1 and 2, Mars Global Surveyor, Mars Odyssey, Mars Reconnaissance Orbiter, Sojourner, Spirit, Opportunity, Curiosity, etc., spacecrafts, which explored the Red Planet we obtained a great deal information about the extremely arid soil and dry air of Mars in the present, and its watery condition in the distant past. Now there is a decade-long, program of robotic exploration of the martian atmosphere and soil - the 'Mars Surveyor Program', which is a series of small, cheap and fast spacecrafts, carrying very few scientific instruments, to be launched about every two years. Here in this paper, under the principles in the United Nations' Agenda 21, we comment on this new phase of Mars exploration under development, which began in 1996, and its benefits to living conditions in developing countries with desert regions. A peaceful regular research of the arid Mars, will help us to understand much better the dynamics of formation of dry regions here on Earth. We suggest that, if the developing countries participate in that program, they will achieve the scientific understanding to create a practical technology, with which they will acquire ways to future transform their arid areas into a more humid places, and to slow the process of desertification of other regions. This, using their own natural resources and own scientific personnel. That would strongly benefit the living conditions in Western Asian countries, which have many desert regions.

  17. Low-Latency Teleoperations for Human Exploration and Evolvable Mars Campaign

    Science.gov (United States)

    Lupisella, Mark; Wright, Michael; Arney, Dale; Gershman, Bob; Stillwagen, Fred; Bobskill, Marianne; Johnson, James; Shyface, Hilary; Larman, Kevin; Lewis, Ruthan; Bleacher, Jake; Gernhardt, Mike; Mueller, Rob; Sanders, Gerald; Watts, Kevin; Eigenbrode, Jen; Garry, Brent; Freeh, Joshua; Manzella, David; Hack, Kurt; Aranyos, Tom

    2015-01-01

    NASA has been analyzing a number of mission concepts and activities that involve low-latency telerobotic (LLT) operations. One mission concept that will be covered in this presentation is Crew-Assisted Sample Return which involves the crew acquiring samples (1) that have already been delivered to space, and or acquiring samples via LLT from orbit to a planetary surface and then launching the samples to space to be captured in space and then returned to the earth with the crew. Both versions of have key roles for low-latency teleoperations. More broadly, the NASA Evolvable Mars Campaign is exploring a number of other activities that involve LLT, such as: (a) human asteroid missions, (b) PhobosDeimos missions, (c) Mars human landing site reconnaissance and site preparation, and (d) Mars sample handling and analysis. Many of these activities could be conducted from Mars orbit and also with the crew on the Mars surface remotely operating assets elsewhere on the surface, e.g. for exploring Mars special regions and or teleoperating a sample analysis laboratory both of which may help address planetary protection concerns. The operational and technology implications of low-latency teleoperations will be explored, including discussion of relevant items in the NASA Technology Roadmap and also how previously deployed robotic assets from any source could subsequently be used by astronauts via LLT.

  18. Crushable Structure for the Landing Impact of a European Mars Exploration Mission (ExoMars 2016)

    Science.gov (United States)

    del Campo, F.; Bernar, E.; Biondetti, G.; Jauregui, Y. E.; Walloschek, T.

    2012-07-01

    The first mission of the ExoMars programme, scheduled to arrive at Mars in 2016, includes an Entry, Descent and Landing Demonstrator Module (EDM). One of the EDM objectives is to demonstrate the possibility to safely absorb the landing impact by means of a deformable structure placed under the Surface Platform (SP), the EDM sub-module reaching ground. This is one of the key technologies in preparation for ESA's contribution to subsequent missions to Mars. SENER is responsible for several structures and mechanisms for the EDM, with TAS-I as Prime contractor. The paper focuses on the Crushable Structure, which is the main element affected by the impact. Its function is to absorb the landing impact after thruster switch off at around 2 meters over the Martian surface, allowing a safe landing for the equipments in terms of acceleration levels, and for the whole structure in terms of stability and non-overturning. An optimized structure has been designed for this purpose, within a restricted envelope, able to meet these requirements for a wide range of terrain configurations, including rocks and slopes.

  19. Evolvable Mars Campaign Long Duration Habitation Strategies: Architectural Approaches to Enable Human Exploration Missions

    Science.gov (United States)

    Simon, Matthew A.; Toups, Larry; Howe, A. Scott; Wald, Samuel I.

    2015-01-01

    The Evolvable Mars Campaign (EMC) is the current NASA Mars mission planning effort which seeks to establish sustainable, realistic strategies to enable crewed Mars missions in the mid-2030s timeframe. The primary outcome of the Evolvable Mars Campaign is not to produce "The Plan" for sending humans to Mars, but instead its intent is to inform the Human Exploration and Operations Mission Directorate near-term key decisions and investment priorities to prepare for those types of missions. The FY'15 EMC effort focused upon analysis of integrated mission architectures to identify technically appealing transportation strategies, logistics build-up strategies, and vehicle designs for reaching and exploring Mars moons and Mars surface. As part of the development of this campaign, long duration habitats are required which are capable of supporting crew with limited resupply and crew abort during the Mars transit, Mars moons, and Mars surface segments of EMC missions. In particular, the EMC design team sought to design a single, affordable habitation system whose manufactured units could be outfitted uniquely for each of these missions and reused for multiple crewed missions. This habitat system must provide all of the functionality to safely support 4 crew for long durations while meeting mass and volume constraints for each of the mission segments set by the chosen transportation architecture and propulsion technologies. This paper describes several proposed long-duration habitation strategies to enable the Evolvable Mars Campaign through improvements in mass, cost, and reusability, and presents results of analysis to compare the options and identify promising solutions. The concepts investigated include several monolithic concepts: monolithic clean sheet designs, and concepts which leverage the co-manifested payload capability of NASA's Space Launch System (SLS) to deliver habitable elements within the Universal Payload Adaptor between the SLS upper stage and the Orion

  20. MOD: An Organic Detector for the Future Exploration of Mars

    Science.gov (United States)

    Kminek, G.; Bada, J. L.; Botta, O.; Grunthaner, F.; Glavin, D. P.

    1999-01-01

    The Mars Organic Detector (MOD) is designed to assess whether organic compounds, possibly associated with life, are present in Martian rock and soil samples. MOD has a detection limit that is at least two orders of magnitude more sensitive than the Viking GCMS. MOD is focused on detecting amino acids, amines and PAH (polycyclic aromatic hydrocarbons). Amino acids play an essential role in biochemistry on Earth and PAH are widespread throughout the universe and can provide an indication of the delivery of meteoritic organic material to Mars. The advantage of MOD is the absence of wet chemistry and its simple and robust design. The sample will be extracted from the mineral matrix (0.1 - 1 g of rock-powder) using sublimation and analyzed with a fluorescence detector. The isolation method is based on the fact that amino acids and PAH are volatile at temperatures greater than 150C. The fluorescence detection scheme is based on UV excitation with LED's, optical filters, PrN diode photon detector and a sample calibration reservoir. Fluorescamine is used as a fluorescing reagent for amino acids and amines, while PAH are naturally fluorescent. There is no sample preparation required and the turnaround time for a single analysis is on the order of minutes.

  1. Solar discrepancies: Mars exploration and the curious problem of inter-planetary time

    Science.gov (United States)

    Mirmalek, Zara Lenora

    The inter-planetary work system for the NASA's Mars Exploration Rovers (MER) mission entailed coordinating work between two corporally diverse workgroups, human beings and solar-powered robots, and between two planets with asynchronous axial rotations. The rotation of Mars takes approximately 24 hours and 40 minutes while for Earth the duration is 24 hours, a differential that was synchronized on Earth by setting a clock forward forty minutes every day. The hours of the day during which the solar-powered rovers were operational constituted the central consideration in the relationship between time and work around which the schedule of MER science operations were organized. And, the operational hours for the rovers were precarious for at least two reasons: on the one hand, the possibility of a sudden and inexplicable malfunction was always present; on the other, the rovers were powered by solar-charged batteries that could simply (and would eventually) fail. Thus, the timetable for the inter-planetary work system was scheduled according to the daily cycle of the sun on Mars and a version of clock time called Mars time was used to keep track of the movement of the sun on Mars. While the MER mission was a success, it does not necessarily follow that all aspects of mission operations were successful. One of the central problems that plagued the organization of mission operations was precisely this construct called "Mars time" even while it appeared that the use of Mars time was unproblematic and central to the success of the mission. In this dissertation, Zara Mirmalek looks at the construction of Mars time as a tool and as a social process. Of particular interest are the consequences of certain (ostensibly foundational) assumptions about the relationship between clock time and the conduct of work that contributed to making the relationship between Mars time and work on Earth appear operational. Drawing on specific examples of breakdowns of Mars time as a support

  2. The Qingdao Twin Registry

    DEFF Research Database (Denmark)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng;

    2013-01-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants...... of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes...

  3. Human Exploration on the Moon, Mars and NEOs: PEX.2/ICEUM12B

    Science.gov (United States)

    Foing, Bernard H.

    2016-07-01

    The session COSPAR-16-PEX.2: "Human Exploration on the Moon, Mars and NEOs", co-sponsored by Commissions B, F will include solicited and contributed talks and poster/interactive presentations. It will also be part of the 12th International Conference on Exploration and Utilisation of the Moon ICEUM12B from the ILEWG ICEUM series started in 1994. It will address various themes and COSPAR communities: - Sciences (of, on, from) the Moon enabled by humans - Research from cislunar and libration points - From robotic villages to international lunar bases - Research from Mars & NEOs outposts - Humans to Phobos/Deimos, Mars and NEOS - Challenges and preparatory technologies, field research operations - Human and robotic partnerships and precursor missions - Resource utilisation, life support and sustainable exploration - Stakeholders for human exploration One half-day session will be dedicated to a workshop format and meetings/reports of task groups: Science, Technology, Agencies, Robotic village, Human bases, Society & Commerce, Outreach, Young Explorers. COSPAR has provided through Commissions, Panels and Working Groups (such as ILEWG, IMEWG) an international forum for supporting and promoting the robotic and human exploration of the Moon, Mars and NEOS. Proposed sponsors : ILEWG, ISECG, IKI, ESA, NASA, DLR, CNES, ASI, UKSA, JAXA, ISRO, SRON, CNSA, SSERVI, IAF, IAA, Lockheed Martin, Google Lunar X prize, UNOOSA

  4. Mimicking Mars: a vacuum simulation chamber for testing environmental instrumentation for Mars exploration.

    Science.gov (United States)

    Sobrado, J M; Martín-Soler, J; Martín-Gago, J A

    2014-03-01

    We have built a Mars environmental simulation chamber, designed to test new electromechanical devices and instruments that could be used in space missions. We have developed this environmental system aiming at validating the meteorological station Rover Environment Monitoring Station of NASA's Mars Science Laboratory mission currently installed on Curiosity rover. The vacuum chamber has been built following a modular configuration and operates at pressures ranging from 1000 to 10(-6) mbars, and it is possible to control the gas composition (the atmosphere) within this pressure range. The device (or sample) under study can be irradiated by an ultraviolet source and its temperature can be controlled in the range from 108 to 423 K. As an important improvement with respect to other simulation chambers, the atmospheric gas into the experimental chamber is cooled at the walls by the use of liquid-nitrogen heat exchangers. This chamber incorporates a dust generation mechanism designed to study Martian-dust deposition while modifying the conditions of temperature, and UV irradiated.

  5. Mimicking Mars: A vacuum simulation chamber for testing environmental instrumentation for Mars exploration

    Energy Technology Data Exchange (ETDEWEB)

    Sobrado, J. M., E-mail: sobradovj@inta.es; Martín-Soler, J. [Centro de Astrobiología (CAB), INTA-CSIC, Torrejón de Ardoz, 28850 Madrid (Spain); Martín-Gago, J. A. [Centro de Astrobiología (CAB), INTA-CSIC, Torrejón de Ardoz, 28850 Madrid (Spain); Instituto de Ciencias de Materiales de Madrid (ICMM-CSIC), Cantoblanco, 28049 Madrid (Spain)

    2014-03-15

    We have built a Mars environmental simulation chamber, designed to test new electromechanical devices and instruments that could be used in space missions. We have developed this environmental system aiming at validating the meteorological station Rover Environment Monitoring Station of NASA's Mars Science Laboratory mission currently installed on Curiosity rover. The vacuum chamber has been built following a modular configuration and operates at pressures ranging from 1000 to 10{sup −6} mbars, and it is possible to control the gas composition (the atmosphere) within this pressure range. The device (or sample) under study can be irradiated by an ultraviolet source and its temperature can be controlled in the range from 108 to 423 K. As an important improvement with respect to other simulation chambers, the atmospheric gas into the experimental chamber is cooled at the walls by the use of liquid-nitrogen heat exchangers. This chamber incorporates a dust generation mechanism designed to study Martian-dust deposition while modifying the conditions of temperature, and UV irradiated.

  6. Human Exploration of Mars Design Reference Architecture 5.0, Addendum #2

    Science.gov (United States)

    Drake, Bret G. (Editor); Watts Kevin D. (Editor)

    2014-01-01

    This report serves as the second Addendum to NASA-SP-2009-566, "Human Exploration of Mars Design Reference Architecture 5.0." The data and descriptions contained within this Addendum capture some of the key assessments and studies produced since publication of the original document, predominately covering those conducted from 2009 through 2012. The assessments and studies described herein are for the most part independent stand-alone contributions. Effort has not been made to assimilate the findings to provide an updated integrated strategy. That is a recognized future effort. This report should not be viewed as constituting a formal plan for the human exploration of Mars.

  7. Destination Deimos: A Design Reference Architecture for Initial Human Exploration of the Mars System

    Science.gov (United States)

    Logan, James S.; Adamo, D. R.

    2011-01-01

    The two biggest challenges to successful human operations in interplanetary space are flight dynamics, constrained by the cold hard physics of the rocket equation, and bioastronautics, the psychophysiological realities of human adaptation, or lack thereof, to the deep space environment. Without substantial innovation in project/mission architecture and vehicle design, human exploration of the Mars system could be problematic for decades. Although a human landing on Mars is inevitable, humans-in-the-loop telerobotic exploration from the outer Martian moon Deimos is the best way to begin. Precursor robotic missions for reconnaissance and local site preparation will be required.

  8. Mars

    CERN Document Server

    Day, Trevor

    2006-01-01

    Discusses the fundamental facts concerning this mysterious planet, including its mass, size, and atmosphere, as well as the various missions that helped planetary scientists document the geological history of Mars. This volume also describes Mars'' seasons with their surface effects on the planet and how they have changed over time.

  9. Applied Superconductivity and Superfluidity for Exploration of the Moon and Mars

    Science.gov (United States)

    Chui, Talso

    2004-01-01

    The initiative for human exploration of the Moon and Mars presents great technical challenges as well as new opportunities for scientific investigations. I will discuss recent developments in superconductivity and superfluidity that can be applied to solve some of these technical challenges. This includes biomedical imaging of astronauts using an array of SQUID magnetometers; resource exploration using SQUID as well as a SQUID-based gravitational gradiometer; measurement of rotational jitter of the Moon and of Mars, for improvement in GPS using a superfluid gyroscope; and the concept of a high precision superfluid clock recently proposed for navigation at JPL. Physicists can also participate as explorers in the Moon/Mars initiative. I will discuss a proposed experiment to search for the postulated strangelet particle (a dark matter candidate) by using the Moon or Mars as a giant detector. As suggest by Nobel Laureate Sheldon Glashow, a massive (approx. 1 ton) strangelet can generate a trail of seismic waves, as it traverses a celestial body. The pristine environments of the Moon and Mars, with their very low seismic backgrounds, are ideal for such an experiment. Very sensitive SQUID-based seismometers can be deployed to increase the sensitivity of strangelet detection.

  10. Mars Exploration Rover Opportunity Mobility Simulation of Traverses at Endeavour Crater, Mars

    Science.gov (United States)

    Coutrot, G. L.; Arvidson, R. E.

    2013-12-01

    Mars Rover Opportunity selected drives over Cape York and Solander Point were simulated using ARTEMIS (Adams-based Rover Terramechanics and Mobility Interaction Simulator), a dynamic computer-based model for rover drives over realistic terrains. Artemis provides insight into how Opportunity responds in terms of rover 3D slip (defined as 100*(1 - actual discance / commanded distance)) and wheel sinkages on tilted surfaces to retrieve soil properties and to have a useful tool for path planning. Elevation data for the simulations were derived from HiRISE setereo observations, complemented by Navcam and Pancam-based elevation maps. Mechanical properties were estimated based on previous drives and tests in the JPL Mars Yard and Mojave Desert. Soil properties were assigned to map cells based on examination of image data and characterization of the extent of bedrock as opposed to soil exposures. Two models were tested: the deformable soil model using the classical terramechanics equations and the contact model using Coulomb's laws of friction. Both models were run and parameters adjusted to match the flight rover 3D slip and wheel sinkage data... The deformable soil model reproduced accurately the drives in terms of rover 3D slip and wheel sinkage. The longitudinal shear deformation modulus and soil cohesion were found to be the two main parameters that strongly impacted results by affecting the shear stresses and slip values. For example, on the uphill segment of Matijevic Hill driven on sol 3212, the simulation requirestwo types of soil over bedrock, one with a cohesion of 2500 Pa and a deformation modulus of 5 mm, and one with a lower cohesion of 1000 Pa and a deformation modulus of 10 mm, matching the geologic map over Matijevic Hill that displays a change in soil type at this location.

  11. ChemCam Education and Public Outreach: Zapping the Public into Awareness of ChemCam, the Mars Science Laboratory, and Mars Science and Exploration

    Science.gov (United States)

    Shaner, A. J.; Shipp, S. S.; Wiens, R. C.; Maurice, S.; Gasnault, O.; Newsom, H.; Anderson, R.

    2012-03-01

    The Chemistry and Camera (ChemCam) instrument EPO program utilizes a public website and educator professional development to capture the public’s interest and imagination in Mars science and exploration.

  12. Mars

    CERN Document Server

    Payment, Simone

    2017-01-01

    This curriculum-based, fun, and approachable book offers everything young readers need to know to begin their study of the Red Planet. They will learn about the fundamental aspects of the Mars, including its size, mass, surface features, interior, orbit, and spin. Further, they will learn about the history of the missions to Mars, including the Viking spacecraft and the Curiosity and MAVEN rovers. Finally, readers will learn about why scientists think there's a chance that Mars is or was suitable for life. With stunning imagery from NASA itself, readers will have a front seat-view of the missi

  13. Eifel field operation campaign supporting Moon Mars and NEO exploration

    Science.gov (United States)

    Kamps, Oscar; Foing, Bernard H.; Offringa, Marloes

    2016-07-01

    As follow-up on the 2009 Eifel field campaign new field tests with our ExoGeoLab lander were conducted in November 2015 and February 2016. The two phase campaign was used to test the usability of a mock-up lander as test bench for experiments and its remote control in a Moon, Mars analogue environment. In a real mission such a lander could be used in a robotic or manned mission as scientific tool for scientists on Earth to do preliminary study on in-situ collected rocks. This could be useful for example for a sample return mission where scientists on Earth can determine if sample is interesting enough for a more detailed study. The prototype lander is one of the components of the ExoGeoLab project from ESA and ILEWG. Several student projects have prepared the lander for a geological field campaign in lunar and Martian analogue terrain. The lander can be divided in three sections which are used to store several components of the lander. The lower compartment can be used to store a rover or used as laboratory. The middle compartment is used for the lander computer(s), spectrometers and the associated cables. The top plate is used for a telescope which in our case is used to observe the environment around the lander and to guide astronauts during their EVA. As closest volcanic are there is chosen to do the Eifel area, Germany. Several stages of volcanism from Devon till Quaternary resulted in a variation of rocks which is analogue to volcanic rocks from Moon, Mars and other near Earth objects. Several topics we would like to test were pre-defined. Functional tests and demo were performed at European astronaut centre prior to the campaign. The latest updates with respect to the remote control were tested. The pressurised transport vehicle was equipped as remote base for (scientific) support during the campaign. The new instrument set-up were tested and some spectra were measured on collected rocks. The telescope was used to study the environment around the lander

  14. Expanding venue and persistence of planetary mobile robotic exploration: new technology concepts for Mars and beyond

    Science.gov (United States)

    Schenker, Paul S.; Elfes, Albert; Hall, Jeffrey L.; Huntsberger, Terrance L.; Jones, Jack A.; Wilcox, Brian H.; Zimmerman, Wayne F.

    2003-10-01

    The domain and technology of mobile robotic space exploration are fast moving from brief visits to benign Mars surface regions to more challenging terrain and sustained exploration. Further, the overall venue and concept of space robotic exploration are expanding—"from flatland to 3D"—from the surface, to sub-surface and aerial theatres on disparate large and small planetary bodies, including Mars, Venus, Titan, Europa, and small asteroids. These new space robotic system developments are being facilitated by concurrent, synergistic advances in software and hardware technologies for robotic mobility, particularly as regard on-board system autonomy and novel thermo-mechanical design. We outline these directions of emerging mobile science mission interest and technology enablement, including illustrative work at JPL on terrain-adaptive and multi-robot cooperative rover systems, aerobotic mobility, and subsurface ice explorers.

  15. Design and Development of a Methane Cryogenic Propulsion Stage for Human Mars Exploration

    Science.gov (United States)

    Percy, Thomas K.; Polsgrove, Tara; Turpin, Jason; Alexander, Leslie

    2016-01-01

    NASA is currently working on the Evolvabe Mars Campaign (EMC) study to outline transportation and mission options for human exploration of Mars. One of the key aspects of the EMC is leveraging current and planned near-term technology investments to build an affordable and evolvable approach to Mars exploration. This leveraging of investments includes the use of high-power Solar Electric Propulsion (SEP) systems, evolved from those currently under development in support of the Asteroid Redirect Mission (ARM), to deliver payloads to Mars. The EMC is considering several transportation options that combine solar electric and chemical propulsion technologies to deliver crew and cargo to Mars. In one primary architecture option, the SEP propulsion system is used to pre-deploy mission elements to Mars while a high-thrust chemical propulsion system is used to send crew on faster ballistic transfers between Earth and Mars. This high-thrust chemical system uses liquid oxygen - liquid methane main propulsion and reaction control systems integrated into the Methane Cryogenic Propulsion Stage (MCPS). Over the past year, there have been several studies completed to provide critical design and development information related to the MCPS. This paper is intended to provide a summary of these efforts. A summary of the current point of departure design for the MCPS is provided as well as an overview of the mission architecture and concept of operations that the MCPS is intended to support. To leverage the capabilities of solar electric propulsion to the greatest extent possible, the EMC architecture pre-deploys to Mars orbit the stages required for returning crew from Mars. While this changes the risk posture of the architecture, it can provide some mass savings by using higher-efficiency systems for interplanetary transfer. However, this does introduce significantly longer flight times to Mars which, in turn, increases the overall lifetime of the stages to as long as 2500 days. This

  16. A U.S. perspective on the human exploration and expansion on the planet Mars

    Science.gov (United States)

    Roberts, Barney B.; Connolly, John F.

    1992-01-01

    A NASA perspective on the human exploration of Mars is presented which is based on the fundamental background available from the many previous studies. A hypothetical architecture of the Mars surface system is described which represents the complete spectrum of envisioned activities. Using the Strategic Implementation Architecture it is possible to construct a thoughtful roadmap which would enable a logical and flexible evolution of missions. Based on that architecture a suite of Martian surface elements is proposed to provide increasing levels of capability to the maturing infrastructure.

  17. Exploration of Mars with the ChemCam LIBS Instrument and the Curiosity Rover

    Science.gov (United States)

    Newsom, Horton E.

    2016-01-01

    The Mars Science Laboratory (MSL) Curiosity rover landed on Mars in August 2012, and has been exploring the planet ever since. Dr. Horton E. Newsom will discuss the MSL's design and main goal, which is to characterize past environments that may have been conducive to the evolution and sustainability of life. He will also discuss Curiosity's science payload, and remote sensing, analytical capabilities, and direct discoveries of the Chemistry & Camera (ChemCam) instrument, which is the first Laser Induced Breakdown Spectrometer (LIBS) to operate on another planetary surface and determine the chemistry of the rocks and soils.

  18. Lunar precursor missions for human exploration of Mars--III: studies of system reliability and maintenance

    Science.gov (United States)

    Mendell, W. W.; Heydorn, R. P.

    2004-01-01

    Discussions of future human expeditions into the solar system generally focus on whether the next explorers ought to go to the Moon or to Mars. The only mission scenario developed in any detail within NASA is an expedition to Mars with a 500-day stay at the surface. The technological capabilities and the operational experience base required for such a mission do not now exist nor has any self-consistent program plan been proposed to acquire them. In particular, the lack of an Abort-to-Earth capability implies that critical mission systems must perform reliably for 3 years or must be maintainable and repairable by the crew. As has been previously argued, a well-planned program of human exploration of the Moon would provide a context within which to develop the appropriate technologies because a lunar expedition incorporates many of the operational elements of a Mars expedition. Initial lunar expeditions can be carried out at scales consistent with the current experience base but can be expanded in any or all operational phases to produce an experience base necessary to successfully and safely conduct human exploration of Mars. Published by Elsevier Ltd.

  19. Design and Development of a Methane Cryogenic Propulsion Stage for Human Mars Exploration

    Science.gov (United States)

    Percy, Thomas K.; Polsgrove, Tara; Turpin, Jason; Alexander, Leslie

    2016-01-01

    NASA is currently working on the Evolvabe Mars Campaign (EMC) study to outline transportation and mission options for human exploration of Mars. One of the key aspects of the EMC is leveraging current and planned near-term technology investments to build an affordable and evolvable approach to Mars exploration. This leveraging of investments includes the use of high-power Solar Electric Propulsion (SEP) systems evolved from those currently under development in support of the Asteroid Redirect Mission to deliver payloads to Mars. The EMC is considering several transportation options that combine solar electric and chemical propulsion technologies to deliver crew and cargo to Mars. In one primary architecture option, the SEP propulsion system is used to pre-deploy mission elements to Mars while a high-thrust chemical propulsion system is used to send crew on faster ballistic transfers between Earth and Mars. This high-thrust chemical system uses liquid oxygen - liquid methane main propulsion and reaction control systems integrated into the Methane Cryogenic Propulsion Stage (MCPS). Over the past year, there have been several studies completed to provide critical design and development information related to the MCPS. This paper is intended to provide a summary of these efforts. A summary of the current point of departure design for the MCPS is provided as well as an overview of the mission architecture and concept of operations that the MCPS is intended to support. To leverage the capabilities of solar electric propulsion to the greatest extent possible, the EMC architecture pre-deploys the required stages for returning crew from Mars. While this changes the risk posture of the architecture, it provides mass savings by using higher-efficiency systems for interplanetary transfer. However, this does introduce significantly longer flight times to Mars which, in turn, increases the overall lifetime of the stages to as long as 3000 days. This unique aspect to the concept

  20. Exploring Subclinical Phenotypic Features in Twin Pairs Discordant for Cleft Lip and Palate

    DEFF Research Database (Denmark)

    Leslie, Elizabeth J; Carlson, Jenna C; Cooper, Margaret E

    2017-01-01

    OBJECTIVE: Monozygotic twins of an individual with an orofacial cleft have a significantly elevated risk for orofacial cleft compared with the general population, but still the concordance rate for orofacial cleft in monozygotic twins is about 40% to 50%. The goal of this study was to determine...... whether unaffected cotwins have an increased frequency of orbicularis oris muscle defects, a subclinical form of orofacial cleft. The presence of such defects may reduce the overall rate of discordance. METHOD: A total of 63 discordant monozygotic and dizygotic twin pairs, 262 unaffected nontwin siblings......, and 543 controls with no history of orofacial clefts were assessed for orbicularis oris defects by high-resolution ultrasound. Frequencies were compared by the Fisher exact test. RESULTS: Unaffected cotwins from discordant monozygotic pairs had a higher frequency of defects (12.5%) than the other test...

  1. Middleware and Web Services for the Collaborative Information Portal of NASA's Mars Exploration Rovers Mission

    Science.gov (United States)

    Sinderson, Elias; Magapu, Vish; Mak, Ronald

    2004-01-01

    We describe the design and deployment of the middleware for the Collaborative Information Portal (CIP), a mission critical J2EE application developed for NASA's 2003 Mars Exploration Rover mission. CIP enabled mission personnel to access data and images sent back from Mars, staff and event schedules, broadcast messages and clocks displaying various Earth and Mars time zones. We developed the CIP middleware in less than two years time usins cutting-edge technologies, including EJBs, servlets, JDBC, JNDI and JMS. The middleware was designed as a collection of independent, hot-deployable web services, providing secure access to back end file systems and databases. Throughout the middleware we enabled crosscutting capabilities such as runtime service configuration, security, logging and remote monitoring. This paper presents our approach to mitigating the challenges we faced, concluding with a review of the lessons we learned from this project and noting what we'd do differently and why.

  2. Preliminary System Analysis of In Situ Resource Utilization for Mars Human Exploration

    Science.gov (United States)

    Rapp, Donald; Andringa, Jason; Easter, Robert; Smith, Jeffrey H .; Wilson, Thomas; Clark, D. Larry; Payne, Kevin

    2005-01-01

    We carried out a system analysis of processes for utilization of Mars resources to support human exploration of Mars by production of propellants from indigenous resources. Seven ISRU processes were analyzed to determine mass. power and propellant storage volume requirements. The major elements of each process include C02 acquisition, chemical conversion, and storage of propellants. Based on a figure of merit (the ratio of the mass of propellants that must be brought from Earth in a non-ISRU mission to the mass of the ISRU system. tanks and feedstocks that must be brought from Earth for a ISRU mission) the most attractive process (by far); is one where indigenous Mars water is accessible and this is processed via Sabatier/Electrolysis to methane and oxygen. These processes are technically relatively mature. Other processes with positive leverage involve reverse water gas shift and solid oxide electrolysis.

  3. Contribution of magnetic measurements onboard NetLander to Mars exploration

    DEFF Research Database (Denmark)

    Menvielle, M.; Musmann, G.; Kuhnke, F.

    2000-01-01

    Lander stations will therefore allow study of both the internal structure of Mars and dynamics of its ionised environment. The expected characteristics of transient magnetic variations, and their relation with plasma how and current in the Mars ionised environment are discussed. The use of the network magnetic......In the frame of the international cooperation for Mars exploration, a set of 4 NetLanders developed by an European consortium is expected to land on the planet during the forthcoming years. Among other instruments, the geophysical package of each lander will include a magnetometer. The different...... possible contributions of magnetic measurements onboard the NetLander stations are presented. Intrinsic planetary field and remanent magnetisation investigations by means of magnetometers onboard a network of landers are first considered, and the information that can be thus derived on the Martian core...

  4. Toward a mobile autonomous robotic system for Mars exploration

    Science.gov (United States)

    Arena, P.; Di Giamberardino, P.; Fortuna, L.; La Gala, F.; Monaco, S.; Muscato, G.; Rizzo, A.; Ronchini, R.

    2004-01-01

    The paper deals with the results obtained up to now in the design and realization of mobile platforms, wheeled and legged ones, for autonomous deployment in unknown and hostile environments: a work developed in the framework of a project supported by the Italian Space Agency. The paper is focused on the description of the hierarchical architecture adopted for the planning, the supervision and the control of their mobility. Experimental results validate the solutions proposed, evidencing the capabilities of the platforms to explore environments in presence of irregular ground shape and obstacles of different dimensions.

  5. Oxidants at the Surface of Mars: A Review in Light of Recent Exploration Results

    Science.gov (United States)

    Lasne, J.; Noblet, A.; Szopa, C.; Navarro-González, R.; Cabane, M.; Poch, O.; Stalport, F.; François, P.; Atreya, S. K.; Coll, P.

    2016-12-01

    In 1976, the Viking landers carried out the most comprehensive search for organics and microbial life in the martian regolith. Their results indicate that Mars' surface is lifeless and, surprisingly, depleted in organics at part-per-billion levels. Several biology experiments on the Viking landers gave controversial results that have since been explained by the presence of oxidizing agents on the surface of Mars. These oxidants may degrade abiotic or biological organics, resulting in their nondetection in the regolith. As several exploration missions currently focus on the detection of organics on Mars (or will do so in the near future), knowledge of the oxidative state of the surface is fundamental. It will allow for determination of the capability of organics to survive on a geological timescale, the most favorable places to seek them, and the best methods to process the samples collected at the surface. With this aim, we review the main oxidants assumed to be present on Mars, their possible formation pathways, and those laboratory studies in which their reactivity with organics under Mars-like conditions has been evaluated. Among the oxidants assumed to be present on Mars, only four have been detected so far: perchlorate ions (ClO4-) in salts, hydrogen peroxide (H2O2) in the atmosphere, and clays and metal oxides composing surface minerals. Clays have been suggested as catalysts for the oxidation of organics but are treated as oxidants in the following to keep the structure of this article straightforward. This work provides an insight into the oxidizing potential of the surface of Mars and an estimate of the stability of organic matter in an oxidizing environment.

  6. Dust aerosol, clouds, and the atmospheric optical depth record over 5 Mars years of the Mars Exploration Rover mission

    CERN Document Server

    Lemmon, Mark T; Bell, James F; Smith, Michael D; Cantor, Bruce A; Smith, Peter H

    2014-01-01

    Dust aerosol plays a fundamental role in the behavior and evolution of the Martian atmosphere. The first five Mars years of Mars Exploration Rover data provide an unprecedented record of the dust load at two sites. This record is useful for characterization of the atmosphere at the sites and as ground truth for orbital observations. Atmospheric extinction optical depths have been derived from solar images after calibration and correction for time-varying dust that has accumulated on the camera windows. The record includes local, regional, and globally extensive dust storms. Comparison with contemporaneous thermal infrared data suggests significant variation in the size of the dust aerosols, with a 1 {\\mu}m effective radius during northern summer and a 2 {\\mu}m effective radius at the onset of a dust lifting event. The solar longitude (LS) 20-136{\\deg} period is also characterized by the presence of cirriform clouds at the Opportunity site, especially near LS=50 and 115{\\deg}. In addition to water ice clouds, ...

  7. Dust Aerosol, Clouds, and the Atmospheric Optical Depth Record over 5 Mars Years of the Mars Exploration Rover Mission

    Science.gov (United States)

    Lemmon, Mark T.; Wolff, Michael J.; Bell, James F., III; Smith, Michael D.; Cantor, Bruce A.; Smith, Peter H.

    2014-01-01

    Dust aerosol plays a fundamental role in the behavior and evolution of the Martian atmosphere. The first five Mars years of Mars Exploration Rover data provide an unprecedented record of the dust load at two sites. This record is useful for characterization of the atmosphere at the sites and as ground truth for orbital observations. Atmospheric extinction optical depths have been derived from solar images after calibration and correction for time-varying dust that has accumulated on the camera windows. The record includes local, regional, and globally extensive dust storms. Comparison with contemporaneous thermal infrared data suggests significant variation in the size of the dust aerosols, with a 1 micrometer effective radius during northern summer and a 2 micrometer effective radius at the onset of a dust lifting event. The solar longitude (L (sub s)) 20-136 degrees period is also characterized by the presence of cirriform clouds at the Opportunity site, especially near LS = 50 and 115 degrees. In addition to water ice clouds, a water ice haze may also be present, and carbon dioxide clouds may be present early in the season. Variations in dust opacity are important to the energy balance of each site, and work with seasonal variations in insolation to control dust devil frequency at the Spirit site.

  8. Groundbreaking Mars Sample Return for Science and Human Exploration

    Science.gov (United States)

    Cohen, Barbara; Draper, David; Eppler, Dean; Treiman, Allan

    2012-01-01

    Partnerships between science and human exploration have recent heritage for the Moon (Lunar Precursor Robotics Program, LPRP) and nearearth objects (Exploration Precursor Robotics Program, xPRP). Both programs spent appreciable time and effort determining measurements needed or desired before human missions to these destinations. These measurements may be crucial to human health or spacecraft design, or may be desired to better optimize systems designs such as spacesuits or operations. Both LPRP and xPRP recommended measurements from orbit, by landed missions and by sample return. LPRP conducted the Lunar Reconnaissance Orbiter (LRO) and Lunar Crater Observation and Sensing Satellite (LCROSS) missions, providing high-resolution visible imagery, surface and subsurface temperatures, global topography, mapping of possible water ice deposits, and the biological effects of radiation [1]. LPRP also initiated a landed mission to provide dust and regolith properties, local lighting conditions, assessment of resources, and demonstration of precision landing [2]. This mission was canceled in 2006 due to funding shortfalls. For the Moon, adequate samples of rocks and regolith were returned by the Apollo and Luna programs to conduct needed investigations. Many near-earth asteroids (NEAs) have been observed from the Earth and several have been more extensively characterized by close-flying missions and landings (NEAR, Hayabusa, Rosetta). The current Joint Robotic Precursor Activity program is considering activities such as partnering with the New Frontiers mission OSIRIS-Rex to visit a NEA and return a sample to the Earth. However, a strong consensus of the NEO User Team within xPRP was that a dedicated mission to the asteroid targeted by humans is required [3], ideally including regolith sample return for more extensive characterization and testing on the Earth.

  9. From LEO, to the Moon and then Mars: Developing a Global Strategy for Exploration Risk Reduction

    Science.gov (United States)

    Laurini, Kathleen C.; Hufenbach, Bernard

    2009-01-01

    Most nations currently involved in human spaceflight, or with such ambitions, believe that space exploration will capture the imagination of our youth resulting in future engineers and scientists, advance technologies which will improve life on earth, increase the knowledge of our solar system, and strengthen bonds and relationships across the globe. The Global Exploration Strategy, published in 2007 by 14 space agencies, eloquently makes this case and presents a vision for space exploration. It argues that in order for space exploration to be sustainable, nations must work together to address the challenges and share the burden of costs. This paper will examine Mars mission scenarios developed by NASA, ESA and other agencies and show resulting conclusions regarding key challenges, needed technologies and associated mission risks. It will discuss the importance of using the International Space Station as a platform for exploration risk reduction and how the global exploration community will develop lunar exploration elements and architectures that enable the long term goal of human missions to Mars. The International Space Station (ISS) is a critical first step both from a technology and capability demonstration point of view, but also from a partnership point of view. There is much work that can be done in low earth orbit for exploration risk reduction. As the current "outpost at the edge of the frontier", the ISS is a place where we can demonstrate certain technologies and capabilities that will substantially reduce the risk of deploying an outpost on the lunar surface and Mars mission scenarios. The ISS partnership is strong and has fulfilled mission needs. Likewise, the partnerships we build on the moon will provide a strong foundation for establishing partnerships for the human Mars missions. On the moon, we build a permanently manned outpost and deploy technologies and capabilities to allow humans to stay for long periods of time. The moon is interesting from

  10. Twin studies as a model for exploring the aetiology of autoimmune thyroid disease

    DEFF Research Database (Denmark)

    Brix, Thomas Heiberg; Hegedüs, Laszlo

    2012-01-01

    triggers such as cigarette smoking, birth characteristics, infection with Yersinia enterocolitica, microchimerism and degree of X chromosome inactivation (XCI) has been evaluated by investigating AITD discordant twin pairs. These studies indicate that smoking, Y. enterocolitica infection and skewed XCI may...

  11. Space suits and life support systems for the exploration of Mars

    Science.gov (United States)

    Kuznetz, Lawrence H.; Gwynne, Owen

    1992-01-01

    The requirements and technologies needed for space suits to be used for the manned exploration of Mars are examined. Alternative concepts are proposed for both the space suit and the portable life support system (collectively called the Extravehicular Mobility Unit, or EMU) needed for Mars exploration. EMU system requirements are outlined. It is pointed out that the most fundamental difference between a Mars EMU and those that preceded it is that the design of a Mars EMU must be driven by science and permanent habitability requirements, while all prior EMU designs have been driven by engineering requirements. The EMU weight issues are discussed, and the system mass and mobility concerns are addressed, along with the backpack-to-body-weight ratio. The challenges of thermal and cosmic radiation protection, micrometeorite protection, and EMU system and crew heat rejection are dealt with briefly, as well as the physiological issues of pressure regulation and bacterial or contaminant isolation. A mathematical model is then presented for evaluation of candidate EMU designs and for concept optimization and selection. Lead technology issues are also discussed.

  12. Human factors research as part of a Mars exploration analogue mission on Devon Island

    Science.gov (United States)

    Binsted, Kim; Kobrick, Ryan L.; Griofa, Marc Ó.; Bishop, Sheryl; Lapierre, Judith

    2010-06-01

    Human factors research is a critical element of space exploration as it provides insight into a crew's performance, psychology and interpersonal relationships. Understanding the way humans work in space-exploration analogue environments permits the development and testing of countermeasures for and responses to potential hazardous situations, and can thus help improve mission efficiency and safety. Analogue missions, such as the one described here, have plausible mission constraints and operational scenarios, similar to those that a real Mars crew would experience. Long duration analogue studies, such as those being conducted at the Flashline Mars Arctic Research Station (FMARS) on Devon Island, Canada, offer an opportunity to study mission operations and human factors in a semi-realistic environment, and contribute to the design of missions to explore the Moon and Mars. The FMARS XI Long Duration Mission (F-XI LDM) was, at four months, the longest designed analogue Mars mission conducted to date, and thus provides a unique insight into human factors issues for long-duration space exploration. Here, we describe the six human factors studies that took place during F-XI LDM, and give a summary of their results, where available. We also present a meta-study, which examined the impact of the human-factors research itself on crew schedule and workload. Based on this experience, we offer some lessons learnt: some aspects (perceived risk and crew motivation, for example) of analogue missions must be realistic for study results to be valid; human factors studies are time-consuming, and should be fully integrated into crew schedules; and crew-ground communication and collaboration under long-term exploration conditions can present serious challenges.

  13. Development of a Thermal Control Architecture for the Mars Exploration Rovers

    Science.gov (United States)

    Novak, Keith S.; Phillips, Charles J.; Birur, Gajanana C.; Sunada, Eric T.; Pauken, Michael T.

    2003-01-01

    In May and June of 2003, the National Aeronautics and Space Administration (NASA) will launch two roving science vehicles on their way to Mars. They will land on Mars in January and February of 2004 and carry out 90-Sol missions. This paper addresses the thermal design architecture of the Mars Exploration Rover (MER) developed for Mars surface operations. The surface atmosphere temperature on Mars can vary from 0°C in the heat of the day to -100°C in the early morning, prior to sunrise. Heater usage at night must be minimized in order to conserve battery energy. The desire to minimize nighttime heater energy led to a design in which all temperature sensitive electronics and the battery were placed inside a well-insulated (carbon-opacified aerogel lined) Warm Electronics Box (WEB). In addition, radioisotope heater units (RHU's, non-electric heat sources) were mounted on the battery and electronics inside the WEB. During the Martian day, the electronics inside the WEB dissipate a large amount of energy (over 710 W*hrs). This heat energy raises the internal temperatures inside the WEB. Hardware items that have similar temperature limits were conductively coupled together to share heat and concentrate thermal mass. Thermal mass helped to minimize temperature increases in the hot case (with maximum internal dissipation) and minimize temperature decreases in the cold case (with minimum internal dissipation). In order to prevent the battery from exceeding its maximum allowable flight temperature, wax-actuated passive thermal switches were placed between the battery and an external radiator. This paper discusses the design philosophies and system requirements that resulted in a successful Mars rover thermal design.

  14. Expedition Memory: Towards Agent-based Web Services for Creating and Using Mars Exploration Data.

    Science.gov (United States)

    Clancey, William J.; Sierhuis, Maarten; Briggs, Geoff; Sims, Mike

    2005-01-01

    Explorers ranging over kilometers of rugged, sometimes "feature-less" terrain for over a year could be overwhelmed by tracking and sharing what they have done and learned. An automated system based on the existing Mobile Agents design [ I ] and Mars Exploration Rover experience [2], could serve as an "expedition memory" that would be indexed by voice as wel1 as a web interface, linking people, places, activities, records (voice notes, photographs, samples). and a descriptive scientific ontology. This database would be accessible during EVAs by astronauts, annotated by the remote science team, linked to EVA plans, and allow cross indexing between sites and expeditions. We consider the basic problem, our philosophical approach, technical methods, and uses of the expedition memory for facilitating long-term collaboration between Mars crews and Earth support teams. We emphasize that a "memory" does not mean a database per se, but an interactive service that combines different resources, and ultimately could be like a helpful librarian.

  15. Applied superconductivity and superfluidity for the exploration of the Moon and Mars

    Science.gov (United States)

    Chui, Talso C P.; Hahn, Inseob; Penanen, Konstantin; Zhong, Fang; Strayer, Donald

    2005-01-01

    We discuss how superconductivity and superfluidity can be applied to solve the challenges in the exploration of the Moon and Mars. High sensitivity instruments using phenomena of superconductivity and superfluidity can potentially make significant contributions to the fields of navigation, automation, habitation, and resource location. Using the quantum nature of superconductivity, lightweight and very sensitive diagnostic tools can be made to monitor the health of astronauts. Moreover, the Moon and Mars offer a unique environment for scientific exploration. We also discuss how powerful superconducting instruments may enable scientists to seek answers to several profound questions about nature. These answers will not only deepen our appreciation of the universe, they may also open the door to paradigm-shifting technologies. c2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

  16. NASA's Advanced Exploration Systems Mars Transit Habitat Refinement Point of Departure Design

    Science.gov (United States)

    Simon, Matthew; Latorella, Kara; Martin, John; Cerro, Jeff; Lepsch, Roger; Jefferies, Sharon; Goodliff, Kandyce; McCleskey, Carey; Smitherman, David; Stromgren, Chel

    2017-01-01

    This paper describes the recently developed point of departure design for a long duration, reusable Mars Transit Habitat, which was established during a 2016 NASA habitat design refinement activity supporting the definition of NASA's Evolvable Mars Campaign. As part of its development of sustainable human Mars mission concepts achievable in the 2030s, the Evolvable Mars Campaign has identified desired durations and mass/dimensional limits for long duration Mars habitat designs to enable the currently assumed solar electric and chemical transportation architectures. The Advanced Exploration Systems Mars Transit Habitat Refinement Activity brought together habitat subsystem design expertise from across NASA to develop an increased fidelity, consensus design for a transit habitat within these constraints. The resulting design and data (including a mass equipment list) contained in this paper are intended to help teams across the agency and potential commercial, academic, or international partners understand: 1) the current architecture/habitat guidelines and assumptions, 2) performance targets of such a habitat (particularly in mass, volume, and power), 3) the driving technology/capability developments and architectural solutions which are necessary for achieving these targets, and 4) mass reduction opportunities and research/design needs to inform the development of future research and proposals. Data presented includes: an overview of the habitat refinement activity including motivation and process when informative; full documentation of the baseline design guidelines and assumptions; detailed mass and volume breakdowns; a moderately detailed concept of operations; a preliminary interior layout design with rationale; a list of the required capabilities necessary to enable the desired mass; and identification of any worthwhile trades/analyses which could inform future habitat design efforts. As a whole, the data in the paper show that a transit habitat meeting the 43

  17. Astrobiology and the Exploration of Gusev Crater by the Mars Exploration Rover Spirit

    Science.gov (United States)

    DesMarais, I. David

    2005-01-01

    We assess the availability of nutrient elements, energy and liquid water on the plains surrounding Columbia Memorial Station by evaluating data from Spirit in the context of previous Mars missions, Earth-based studies of martian meteorites and studies of microbial communities on Earth that represent potential analogs of martian biota. The compositions of Gusev basalts resemble those of olivine basalts beneath the seabed on Earth that deep drilling has shown to support life. Of particular relevance to biology, phosphate abundances are much greater in Gusev basalts (0.84 +/- 0.07 wt. % P2O5) than in oceanic basalts (typically 0.06 wt. %).

  18. The Search for Biosignatures on Mars: Using Predictive Geology to Optimize Exploration Targets

    Science.gov (United States)

    Oehler, Dorothy Z.; Allen, Carlton C.

    2011-01-01

    Predicting geologic context from satellite data is a method used on Earth for exploration in areas with limited ground truth. The method can be used to predict facies likely to contain organic-rich shales. Such shales concentrate and preserve organics and are major repositories of organic biosignatures on Earth [1]. Since current surface conditions on Mars are unfavorable for development of abundant life or for preservation of organic remains of past life, the chances are low of encountering organics in surface samples. Thus, focusing martian exploration on sites predicted to contain organic-rich shales would optimize the chances of discovering evidence of life, if it ever existed on that planet.

  19. Science applications of a multispectral microscopic imager for the astrobiological exploration of Mars

    Science.gov (United States)

    Nunez, Jorge; Farmer, Jack; Sellar, R. Glenn; Swayze, Gregg A.; Blaney, Diana L.

    2014-01-01

    Future astrobiological missions to Mars are likely to emphasize the use of rovers with in situ petrologic capabilities for selecting the best samples at a site for in situ analysis with onboard lab instruments or for caching for potential return to Earth. Such observations are central to an understanding of the potential for past habitable conditions at a site and for identifying samples most likely to harbor fossil biosignatures. The Multispectral Microscopic Imager (MMI) provides multispectral reflectance images of geological samples at the microscale, where each image pixel is composed of a visible/shortwave infrared spectrum ranging from 0.46 to 1.73 μm. This spectral range enables the discrimination of a wide variety of rock-forming minerals, especially Fe-bearing phases, and the detection of hydrated minerals. The MMI advances beyond the capabilities of current microimagers on Mars by extending the spectral range into the infrared and increasing the number of spectral bands. The design employs multispectral light-emitting diodes and an uncooled indium gallium arsenide focal plane array to achieve a very low mass and high reliability. To better understand and demonstrate the capabilities of the MMI for future surface missions to Mars, we analyzed samples from Mars-relevant analog environments with the MMI. Results indicate that the MMI images faithfully resolve the fine-scale microtextural features of samples and provide important information to help constrain mineral composition. The use of spectral endmember mapping reveals the distribution of Fe-bearing minerals (including silicates and oxides) with high fidelity, along with the presence of hydrated minerals. MMI-based petrogenetic interpretations compare favorably with laboratory-based analyses, revealing the value of the MMI for future in situ rover-mediated astrobiological exploration of Mars.

  20. Science applications of a multispectral microscopic imager for the astrobiological exploration of Mars.

    Science.gov (United States)

    Núñez, Jorge I; Farmer, Jack D; Sellar, R Glenn; Swayze, Gregg A; Blaney, Diana L

    2014-02-01

    Future astrobiological missions to Mars are likely to emphasize the use of rovers with in situ petrologic capabilities for selecting the best samples at a site for in situ analysis with onboard lab instruments or for caching for potential return to Earth. Such observations are central to an understanding of the potential for past habitable conditions at a site and for identifying samples most likely to harbor fossil biosignatures. The Multispectral Microscopic Imager (MMI) provides multispectral reflectance images of geological samples at the microscale, where each image pixel is composed of a visible/shortwave infrared spectrum ranging from 0.46 to 1.73 μm. This spectral range enables the discrimination of a wide variety of rock-forming minerals, especially Fe-bearing phases, and the detection of hydrated minerals. The MMI advances beyond the capabilities of current microimagers on Mars by extending the spectral range into the infrared and increasing the number of spectral bands. The design employs multispectral light-emitting diodes and an uncooled indium gallium arsenide focal plane array to achieve a very low mass and high reliability. To better understand and demonstrate the capabilities of the MMI for future surface missions to Mars, we analyzed samples from Mars-relevant analog environments with the MMI. Results indicate that the MMI images faithfully resolve the fine-scale microtextural features of samples and provide important information to help constrain mineral composition. The use of spectral endmember mapping reveals the distribution of Fe-bearing minerals (including silicates and oxides) with high fidelity, along with the presence of hydrated minerals. MMI-based petrogenetic interpretations compare favorably with laboratory-based analyses, revealing the value of the MMI for future in situ rover-mediated astrobiological exploration of Mars.

  1. Jezero Crater, Mars, as a Compelling Site for Future In Situ Exploration

    Science.gov (United States)

    Goudge, T. A.; Ehlmann, B. L.; Fassett, C. I.; Head, J. W.; Mustard, J. F.; Mangold, N.; Gupta, S.; Milliken, R. E.; Brown, A. J.

    2017-01-01

    Jezero is a approximately 45 km diameter impact crater located in the Nili Fossae region of Mars. Jezero is an outstanding site to address key questions of ancient Mars climate, habitability, and volcanic history because: (a) It hosted an open-basin lake during the era of valley network formation [1,2], which ceased at approximately the Noachian-Hesperian boundary [3]. (b) It contains two delta deposits [1,4] with Fe/Mg-smectite and Mg-carbonate sediment [4-7] (the only exposure of lacus-trine shoreline carbonates seen so far on Mars). (c) The depositional environment and mineral assemblage of the delta are promising for the concentration and preservation of organic matter [5,8]. (d) The diverse geologic units in Jezero are in clear stratigraphic context [7]. The Jezero paleolake system has been thoroughly investigated at a variety of scales, including work on: the mineralogy of the delta deposits [4-6] and watershed [7], as well as the morphology and sedimentology of the basin [9] and delta deposits [1,4]. The geologic context of Jezero is also well-studied given the broad suite of alteration minerals exposed in the ancient stratigraphies of the Nili Fossae region [e.g., 6,10-13]. Here we present an overview of the units accessible for exploration in the Jezero basin, including questions and hypotheses that can be tested through analysis in situ and of returned samples. This is particularly timely given the upcoming Mars 2020 mission, for which Jezero is one of the final eight landing sites [14]. Primary science objectives for Mars 2020 are to: (1) characterize the geologic history of a site with "evidence of an astrobiologically-relevant ancient environment and geologic diversity"; (2) assess the habitability and "potential evidence of past life" in units with "high biosignature preservation potential"; and (3) cache scientifically compelling samples for potential return to Earth [15].

  2. A low-cost approach to the exploration of Mars through a robotic technology demonstrator mission

    Science.gov (United States)

    Ellery, Alex; Richter, Lutz; Parnell, John; Baker, Adam

    2003-11-01

    We present a proposed robotic mission to Mars - Vanguard - for the Aurora Arrow programme which combines an extensive technology demonstrator with a high scientific return. The novel aspect of this technology demonstrator is the demonstration of "water mining" capabilities for in-situ resource utilisation in conjunction with high-value astrobiological investigation within a low mass lander package of 70 kg. The basic architecture comprises a small lander, a micro-rover and a number of ground-penetrating moles. This basic architecture offers the possibility of testing a wide variety of generic technologies associated with space systems and planetary exploration. The architecture provides for the demonstration of specific technologies associated with planetary surface exploration, and with the Aurora programme specifically. Technology demonstration of in-situ resource utilisation will be a necessary precursor to any future human mission to Mars. Furthermore, its modest mass overhead allows the reuse of the already built Mars Express bus, making it a very low cost option.

  3. Climate Twins - a tool to explore future climate impacts by assessing real world conditions: Exploration principles, underlying data, similarity conditions and uncertainty ranges

    Science.gov (United States)

    Loibl, Wolfgang; Peters-Anders, Jan; Züger, Johann

    2010-05-01

    To achieve public awareness and thorough understanding about expected climate changes and their future implications, ways have to be found to communicate model outputs to the public in a scientifically sound and easily understandable way. The newly developed Climate Twins tool tries to fulfil these requirements via an intuitively usable web application, which compares spatial patterns of current climate with future climate patterns, derived from regional climate model results. To get a picture of the implications of future climate in an area of interest, users may click on a certain location within an interactive map with underlying future climate information. A second map depicts the matching Climate Twin areas according to current climate conditions. In this way scientific output can be communicated to the public which allows for experiencing climate change through comparison with well-known real world conditions. To identify climatic coincidence seems to be a simple exercise, but the accuracy and applicability of the similarity identification depends very much on the selection of climate indicators, similarity conditions and uncertainty ranges. Too many indicators representing various climate characteristics and too narrow uncertainty ranges will judge little or no area as regions with similar climate, while too little indicators and too wide uncertainty ranges will address too large regions as those with similar climate which may not be correct. Similarity cannot be just explored by comparing mean values or by calculating correlation coefficients. As climate change triggers an alteration of various indicators, like maxima, minima, variation magnitude, frequency of extreme events etc., the identification of appropriate similarity conditions is a crucial question to be solved. For Climate Twins identification, it is necessary to find a right balance of indicators, similarity conditions and uncertainty ranges, unless the results will be too vague conducting a

  4. Dust Accumulation and Solar Panel Array Performance on the Mars Exploration Rover (MER) Project

    Science.gov (United States)

    Turgay, Eren H.

    2004-01-01

    One of the most fundamental design considerations for any space vehicle is its power supply system. Many options exist, including batteries, fuel cells, nuclear reactors, radioisotopic thermal generators (RTGs), and solar panel arrays. Solar arrays have many advantages over other types of power generation. They are lightweight and relatively inexpensive, allowing more mass and funding to be allocated for other important devices, such as scientific instruments. For Mars applications, solar power is an excellent option, especially for long missions. One might think that dust storms would be a problem; however, while dust blocks some solar energy, it also scatters it, making it diffuse rather than beamed. Solar cells are still able to capture this diffuse energy and convert it into substantial electrical power. For these reasons, solar power was chosen to be used on the 1997 Mars Pathfinder mission. The success of this mission set a precedent, as NASA engineers have selected solar power as the energy system of choice for all future Mars missions, including the Mars Exploration Rover (MER) Project. Solar sells have their drawbacks, however. They are difficult to manufacture and are relatively fragile. In addition, solar cells are highly sensitive to different parts of the solar spectrum, and finding the correct balance is crucial to the success of space missions. Another drawback is that the power generated is not a constant with respect to time, but rather changes with the relative angle to the sun. On Mars, dust accumulation also becomes a factor. Over time, dust settles out of the atmosphere and onto solar panels. This dust blocks and shifts the frequency of the incoming light, degrading solar cell performance. My goal is to analyze solar panel telemetry data from the two MERs (Spirit and Opportunity) in an effort to accurately model the effect of dust accumulation on solar panels. This is no easy process due to the large number of factors involved. Changing solar

  5. Dust Accumulation and Solar Panel Array Performance on the Mars Exploration Rover (MER) Project

    Science.gov (United States)

    Turgay, Eren H.

    2004-01-01

    One of the most fundamental design considerations for any space vehicle is its power supply system. Many options exist, including batteries, fuel cells, nuclear reactors, radioisotopic thermal generators (RTGs), and solar panel arrays. Solar arrays have many advantages over other types of power generation. They are lightweight and relatively inexpensive, allowing more mass and funding to be allocated for other important devices, such as scientific instruments. For Mars applications, solar power is an excellent option, especially for long missions. One might think that dust storms would be a problem; however, while dust blocks some solar energy, it also scatters it, making it diffuse rather than beamed. Solar cells are still able to capture this diffuse energy and convert it into substantial electrical power. For these reasons, solar power was chosen to be used on the 1997 Mars Pathfinder mission. The success of this mission set a precedent, as NASA engineers have selected solar power as the energy system of choice for all future Mars missions, including the Mars Exploration Rover (MER) Project. Solar sells have their drawbacks, however. They are difficult to manufacture and are relatively fragile. In addition, solar cells are highly sensitive to different parts of the solar spectrum, and finding the correct balance is crucial to the success of space missions. Another drawback is that the power generated is not a constant with respect to time, but rather changes with the relative angle to the sun. On Mars, dust accumulation also becomes a factor. Over time, dust settles out of the atmosphere and onto solar panels. This dust blocks and shifts the frequency of the incoming light, degrading solar cell performance. My goal is to analyze solar panel telemetry data from the two MERs (Spirit and Opportunity) in an effort to accurately model the effect of dust accumulation on solar panels. This is no easy process due to the large number of factors involved. Changing solar

  6. Principal Components Analysis of Reflectance Spectra from the Mars Exploration Rover Opportunity

    Science.gov (United States)

    Mercer, C. M.; Cohen, B. A.

    2010-01-01

    In the summer of 2007 a global dust storm on Mars effectively disabled Opportunity's Miniature Thermal Emission Spectrometer (Mini-TES), the primary instrument used by the Athena Science Team to identify locally unique rocks on the Martian surface. The science team needs another way to distinguish interesting rocks from their surroundings on a tactical timescale. This study was designed to develop the ability to identify locally unique rocks on the Martian surface remotely using the Mars Exploration Rovers' Panoramica Camera (PanCam) instrument. Meridiani bedrock observed by Opportunity is largely characterized by sulfate-rich sandstones and hematite spherules. Additionally, loose fragments of bedrock and "cobbles" of foreign origin collet on the surface, some of which are interpreted as meteorites.

  7. Contribution of magnetic measurements onboard NetLander to Mars exploration

    DEFF Research Database (Denmark)

    Menvielle, M.; Musmann, G.; Kuhnke, F.

    2000-01-01

    between the environment of the planet and solar radiation, and a secondary source, the electric currents induced in the conductive planet. The continuous recording of the time variations of the magnetic field at the surface of Mars by means of three component magnetometers installed onboard Net......In the frame of the international cooperation for Mars exploration, a set of 4 NetLanders developed by an European consortium is expected to land on the planet during the forthcoming years. Among other instruments, the geophysical package of each lander will include a magnetometer. The different...... possible contributions of magnetic measurements onboard the NetLander stations are presented. Intrinsic planetary field and remanent magnetisation investigations by means of magnetometers onboard a network of landers are first considered, and the information that can be thus derived on the Martian core...

  8. Raman spectroscopic analysis of arctic nodules: relevance to the astrobiological exploration of Mars.

    Science.gov (United States)

    Jorge-Villar, Susana E; Edwards, Howell G M; Benning, Liane G

    2011-11-01

    The discovery of small, spherical nodules termed 'blueberries' in Gusev Crater on Mars, by the NASA rover Opportunity has given rise to much debate on account of their interesting and novel morphology. A terrestrial analogue in the form of spherical nodules of similar size and morphology has been analysed using Raman spectroscopy; the mineralogical composition has been determined and evidence found for the biological colonisation of these nodules from the spectral signatures of cyanobacterial protective biochemical residues such as scytonemin, carotenoids, phycocyanins and xanthophylls. This is an important result for the recognition of future sites for the planned astrobiological exploration of planetary surfaces using remote robotic instrumentation in the search for extinct and extant life biosignatures and for the expansion of putative terrestrial Mars analogue geological niches and morphologies.

  9. Low-latency Science Exploration of Planetary Bodies: a Demonstration Using ISS in Support of Mars Human Exploration

    Science.gov (United States)

    Thronson, Harley A.; Valinia, Azita; Bleacher, Jacob; Eigenbrode, Jennifer; Garvin, Jim; Petro, Noah

    2014-01-01

    We summarize a proposed experiment to use the International Space Station to formally examine the application and validation of low-latency telepresence for surface exploration from space as an alternative, precursor, or potentially as an adjunct to astronaut "boots on the ground." The approach is to develop and propose controlled experiments, which build upon previous field studies and which will assess the effects of different latencies (0 to 500 msec), task complexity, and alternate forms of feedback to the operator. These experiments serve as an example of a pathfinder for NASA's roadmap of missions to Mars with low-latency telerobotic exploration as a precursor to astronaut's landing on the surface to conduct geological tasks.

  10. Visible and near-infrared multispectral analysis of rocks at Meridiani Planum, Mars, by the Mars Exploration Rover Opportunity

    Science.gov (United States)

    Farrand, W. H.; Bell, J.F.; Johnson, J. R.; Jolliff, B.L.; Knoll, A.H.; McLennan, S.M.; Squyres, S. W.; Calvin, W.M.; Grotzinger, J.P.; Morris, R.V.; Soderblom, J.; Thompson, S.D.; Watters, W.A.; Yen, A. S.

    2007-01-01

    Multispectral measurements in the visible and near infrared of rocks at Meridiani Planum by the Mars Exploration Rover Opportunity's Pancam are described. The Pancam multispectral data show that the outcrops of the Burns formation consist of two main spectral units which in stretched 673, 535, 432 nm color composites appear buff- and purple-colored. These units are referred to as the HFS and LFS spectral units based on higher and lower values of 482 to 535 nm slope. Spectral characteristics are consistent with the LFS outcrop consisting of less oxidized, and the HFS outcrop consisting of more oxidized, iron-bearing minerals. The LFS surfaces are not as common and appear, primarily, at the distal ends of outcrop layers and on steep, more massive surfaces, locations that are subject to greater eolian erosion. Consequently, the HFS surfaces are interpreted as a weathering rind. Further inherent spectral differences between layer's and between different outcrop map units, both untouched and patches abraded by the rover's Rock Abrasion Tool, are also described. Comparisons of the spectral parameters of the Meridiani outcrop with a set of laboratory reflectance measurements of Fe3+-bearing minerals show that the field of outcrop measurements plots near the fields of hematite, ferrihydrite, poorly crystalline goethite, and schwertmannite. Rind and fracture fill materials, observed intermittently at outcrop exposures, are intermediate in their spectral character between both the HFS and LFS spectral classes and other, less oxidized, surface materials (basaltic sands, spherules, and cobbles). Copyright 2007 by the American Geophysical Union.

  11. Channel and tube flow features associated with the Twin Craters Lava Flow, Zuni-Bandera Volcanic Field, NM: Insights into similar features on Mars

    Science.gov (United States)

    Samuels, R.; deWet, A.; Bleacher, J. E.; von Meerscheidt, H. C.; Hamilton, C.; Garry, W. B.

    2013-12-01

    The Zuni-Bandera Volcanic Field lies near the center of the Jemez lineament that extends from central Arizona to northeastern New Mexico. The Jemez lineament is a result of rifting in the Earth's crust and is associated with volcanic activity that spans the last 16 Ma. The youngest volcanic activity associated with the lineament includes basaltic lava that was erupted 3 ka ago to form the McCartys Flow. The Twin Craters flow is moderately older (18.0 ka), but it also well-preserved and provides an ideal location to investigate volcanic processes and landforms. In this study, we combined detailed field observations and mapping with remote sensing to better understand variations in morphology along the transport system of the flow . The Twin Craters flow is characterized as an aā and tube-fed pāhoehoe flow with braided or branching tubes and channels; and associated aā and pāhoehoe break-outs. It is possible that the variations in morphology along the same transport structure might be related to pre-flow slope, which might have also been variable along flow. Shatter ring features are thought to be related to changes in eruption rate, and therefore, local flux through the system. However, over-pressurization of the tube might also be related to changes in local discharge rate associated with the ponding and release of lava within the transport system that may be due to interactions between the lava and obstacles along the flow's path (see Mallonee et al., this meeting). Many of these features are similar to features present in the Tharsis Montes region of Mars and particularly on the southern apron of Ascraeus Mons. The detailed description of the morphology of the Twin Craters Lava Flow and the understanding of the emplacement mechanisms will be crucial in identifying the processes that formed the Ascraeus flows and channels. This will aid in determining if the lava surface textures are directly related to eruption conditions or if they have been significantly

  12. Development and Demonstration of Sustainable Surface Infrastructure for Moon/Mars Exploration

    Science.gov (United States)

    Sanders, Gerald B.; Larson, William E.; Picard, Martin

    2011-01-01

    For long-term human exploration of the Moon and Mars to be practical, affordable, and sustainable, future missions must be able to identify and utilize resources at the site of exploration. The ability to characterize, extract, processes, and separate products from local material, known as In-Situ Resource Utilization (ISRU), can provide significant reductions in launch mass, logistics, and development costs while reducing risk through increased mission flexibility and protection as well as increased mission capabilities in the areas of power and transportation. Making mission critical consumables like propellants, fuel cell reagents and life support gases, as well as in-situ crew/hardware protection and energy storage capabilities can significantly enhance robotic and human science and exploration missions, however other mission systems need to be designed to interface with and utilize these in-situ developed products and services from the start or the benefits will be minimized or eliminated. This requires a level of surface and transportation system development coordination not typically utilized during early technology and system development activities. An approach being utilized by the US National Aeronautics and Space Administration and the Canadian Space Agency has been to utilize joint analogue field demonstrations to focus technology development activities to demonstrate and integrate new and potentially game changing. mission critical capabilities that would enable an affordable and sustainable surface infrastructure for lunar and Mars robotic and human exploration. Two analogue field tests performed in November 2008 and February 2010 demonstrated first generation capabilities for lunar resource prospecting, exploration site preparation, and oxygen extraction from regolith while initiating integration with mobility, science, fuel cell power, and propulsion disciplines. A third analogue field test currently planned for June 2012 will continue and expand

  13. Human Exploration Ethnography of the Haughton-Mars Project, 1998-1999

    Science.gov (United States)

    Clancey, William J.; Swanson, Keith (Technical Monitor)

    1999-01-01

    During the past two field seasons, July 1988 and 1999, we have conducted research about the field practices of scientists and engineers at Haughton Crater on Devon Island in the Canadian Arctic, with the objective of determining how people will live and work on Mars. This broad investigation of field life and work practice, part of the Haughton-Mars Project lead by Pascal Lee, spans social and cognitive anthropology, psychology, and computer science. Our approach involves systematic observation and description of activities, places, and concepts, constituting an ethnography of field science at Haughton. Our focus is on human behaviors-what people do, where, when, with whom, and why. By locating behavior in time and place-in contrast with a purely functional or "task oriented" description of work-we find patterns constituting the choreography of interaction between people, their habitat, and their tools. As such, we view the exploration process in terms of a total system comprising a social organization, facilities, terrain/climate, personal identities, artifacts, and computer tools. Because we are computer scientists seeking to develop new kinds of tools for living and working on Mars, we focus on the existing representational tools (such as documents and measuring devices), learning and improvization (such as use of the internet or informal assistance), and prototype computational systems brought to the field. Our research is based on partnership, by which field scientists and engineers actively contribute to our findings, just as we participate in their work and life.

  14. Wind-Driven Wireless Networked System of Mobile Sensors for Mars Exploration

    Science.gov (United States)

    Davoodi, Faranak; Murphy, Neil

    2013-01-01

    A revolutionary way is proposed of studying the surface of Mars using a wind-driven network of mobile sensors: GOWON. GOWON would be a scalable, self-powered and autonomous distributed system that could allow in situ mapping of a wide range of environmental phenomena in a much larger portion of the surface of Mars compared to earlier missions. It could improve the possibility of finding rare phenomena such as "blueberries' or bio-signatures and mapping their occurrence, through random wind-driven search. It would explore difficult terrains that were beyond the reach of previous missions, such as regions with very steep slopes and cluttered surfaces. GOWON has a potentially long life span, as individual elements can be added to the array periodically. It could potentially provide a cost-effective solution for mapping wide areas of Martian terrain, enabling leaving a long-lasting sensing and searching infrastructure on the surface of Mars. The system proposed here addresses this opportunity using technology advances in a distributed system of wind-driven sensors, referred to as Moballs.

  15. Ground Truthing Orbital Clay Mineral Observations with the APXS Onboard Mars Exploration Rover Opportunity

    Science.gov (United States)

    Schroeder, C.; Gellert, R.; VanBommel, S.; Clark, B. C.; Ming, D. W.; Mittlefehldt, D. S.; Yen, A. S.

    2016-01-01

    NASA's Mars Exploration Rover Opportunity has been exploring approximately 22 km diameter Endeavour crater since 2011. Its rim segments predate the Hesperian-age Burns formation and expose Noachian-age material, which is associated with orbital Fe3+-Mg-rich clay mineral observations [1,2]. Moving to an orders of magnitude smaller instrumental field of view on the ground, the clay minerals were challenging to pinpoint on the basis of geochemical data because they appear to be the result of near-isochemical weathering of the local bedrock [3,4]. However, the APXS revealed a more complex mineral story as fracture fills and so-called red zones appear to contain more Al-rich clay minerals [5,6], which had not been observed from orbit. These observations are important to constrain clay mineral formation processes. More detail will be added as Opportunity is heading into her 10th extended mission, during which she will investigate Noachian bedrock that predates Endeavour crater, study sedimentary rocks inside Endeavour crater, and explore a fluid-carved gully. ESA's ExoMars rover will land on Noachian-age Oxia Planum where abundant Fe3+-Mg-rich clay minerals have been observed from orbit, but the story will undoubtedly become more complex once seen from the ground.

  16. Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration

    Science.gov (United States)

    Gisser, D. G.; Frederick, D. K.; Lashmet, P. K.; Sandor, G. N.; Shen, C. N.; Yerazunis, S. Y.

    1975-01-01

    Problems related to an unmanned exploration of the planet Mars by means of an autonomous roving planetary vehicle are investigated. These problems include: design, construction and evaluation of the vehicle itself and its control and operating systems. More specifically, vehicle configuration, dynamics, control, propulsion, hazard detection systems, terrain sensing and modelling, obstacle detection concepts, path selection, decision-making systems, and chemical analyses of samples are studied. Emphasis is placed on development of a vehicle capable of gathering specimens and data for an Augmented Viking Mission or to provide the basis for a Sample Return Mission.

  17. Exploration of amino acid biomarkers in polar ice with the Mars Organic Analyzer

    Science.gov (United States)

    Jayarajah, C.; Botta, O.; Aubrey, A.; Parker, E.; Bada, J.; Mathies, R.

    2009-05-01

    A portable microfabricated capillary electrophoresis (CE) system named the Mars Organic Analyzer (MOA) has been developed to analyze fluorescently-labeled biomarkers including amino acids, amines, nucleobases, and amino sugars with the goal of life detection on Mars (1,2). This technology has also been shown to be effective in screening the formation of biogenic amines during fermentation (3). The MOA is a part of the Urey instrument package that has been selected for the 2016 European ExoMars mission by ESA. The identification of recent gully erosion sites, observations of ice on and beneath the surface of Mars, and the discovery of large reservoirs of sub-surface ice on Mars point to water-ice as an important target for astrobiological analyses. In addition, the ice samples on the Moon, Mercury, Europa and Enceladus are of interest due to the possibility that they may contain information on biogenic material relevant to the evolution of life. We explore here the use of the MOA instrument for the analysis of amino acids in polar ice samples. The amino acids valine, alanine/serine, glycine, glutamic acid, and aspartic acid were found in the parts-per-billion range from Greenland ice-core samples. Chiral analysis of these samples yielded D/L ratios of 0.51/0.09 for alanine/serine and 0.14/0.06 for aspartic acid. Individual amino acids in the parts-per-trillion range were found in Antarctic ice samples collected from the surface of a meteorite collection area. The distinct amino acid and amine content of these samples indicates that further biomarker characterization of ice samples as a function of sampling location, depth, and structural features will be highly informative. The rapid sensitive analysis capabilities demonstrated here establish the feasibility of using the MOA to analyze the biomarker content of ice samples in planetary exploration. 1. Skelley, A. M.; Scherer, J. R.; Aubrey, A. D.; Grover, W. H.; Ivester, R. H. C., Ehrenfreund, P.; Grunthaner, F. J

  18. The Ancient Habitability of Gale Crater, Mars, after Four Years of Exploration by Curiosity

    Science.gov (United States)

    Vasavada, Ashwin R.; Gupta, Sanjeev; Mars Science Laboratory Science Team

    2016-10-01

    The Mars Science Laboratory (MSL) Curiosity rover landed in August 2012 with the goal of assessing the habitability of environments dating from the Noachian-Hesperian boundary, a time when Mars was undergoing a major climatic change from wetter to drier conditions. The stratified and mineralogically diverse foothills of Gale crater's central mound, Aeolis Mons, retain a record of this key period. Prior to reaching Aeolis Mons, ancient habitable environments were found on the surrounding plains. At Yellowknife Bay, geological, geochemical, and mineralogical analyses of the lacustrine Sheepbed mudstone indicated a near-neutral pH and low salinity environment with the key chemical elements required by life and potential sources of energy to fuel microbial metabolism. As the rover traversed across the plains, evidence for ancient fluvial and deltaic systems pointed toward the hypothesis that lower Aeolis Mons was built up from sediments deposited within a series of lakes that once filled the central basin of the crater. Upon reaching the mountain in September 2014, Curiosity found an array of fluvial, lacustrine, and aeolian strata that also show a complex pattern of post-depositional alteration. The basal outcrops that form the lowest stratigraphic unit of Aeolis Mons, the Murray formation, are characterized predominantly by mudstones with minor intercalated sandstones. The mudstone facies show abundant fine-scale planar laminations throughout the Murray formation succession and are interpreted to record deposition in an ancient lacustrine system in Gale crater. Curiosity has explored 40 m of the ~ 200-m thick Murray formation. If the entire section is lacustrine, it would imply that lakes were stable in Gale crater over a period of at least millions of years, challenging present climate models that cannot account for the temperate and humid conditions needed to sustain long-lived open lakes on early Mars. This presentation will review how Curiosity's geological and

  19. Declining Lake Habitats in the Andes: Implications for Early Mars, Life, and Exploration (Invited)

    Science.gov (United States)

    Cabrol, N. A.; Grin, E. A.; High Lakes Project Team

    2010-12-01

    /Hesperian transition makes them uniquely similar to early martian lakes and a window into the likely transformation they experienced during the transition period from a wet to a dry Mars. Our results show that decline was unlikely to be monotonical over time on Mars, and therefore probably challenging for putative life, if any, to adapt to. Physicochemical changes associated with such variability are significant. There is currently no data to show how this environmental roller coaster impacts biodiversity at the level of the overall population’s density or that of the species. However, the relatively low diversity found in the samples of the microbial community is consistent with biodiversity loss and selection of specific species capable of mutating and adapting rapidly. The timing of key cycles appears critical to the ecosystem’s survival. Here, we will discuss our latest results, the main similarities and differences with Mars, and how exploring these analogs help us better learn how to identify their signatures on Mars.

  20. Red rover: inside the story of robotic space exploration, from genesis to the mars rover curiosity

    CERN Document Server

    Wiens, Roger

    2013-01-01

    In its eerie likeness to Earth, Mars has long captured our imaginations—both as a destination for humankind and as a possible home to extraterrestrial life. It is our twenty-first century New World; its explorers robots, shipped 350 million miles from Earth to uncover the distant planet’s secrets.Its most recent scout is Curiosity—a one-ton, Jeep-sized nuclear-powered space laboratory—which is now roving the Martian surface to determine whether the red planet has ever been physically capable of supporting life. In Red Rover, geochemist Roger Wiens, the principal investigator for the ChemCam laser instrument on the rover and veteran of numerous robotic NASA missions, tells the unlikely story of his involvement in sending sophisticated hardware into space, culminating in the Curiosity rover's amazing journey to Mars.In so doing, Wiens paints the portrait of one of the most exciting scientific stories of our time: the new era of robotic space exploration. Starting with NASA’s introduction of the Discovery...

  1. The Astrobiology of the Subsurface: Exploring Cave Habitats on Earth, Mars and Beyond

    Science.gov (United States)

    Boston, Penelope Jane

    2016-01-01

    We are using the spectacular underground landscapes of Earth caves as models for the subsurfaces of other planets. Caves have been detected on the Moon and Mars and are strongly suspected for other bodies in the Solar System including some of the ice covered Ocean Worlds that orbit gas giant planets. The caves we explore and study include many extreme conditions of relevance to planetary astrobiology exploration including high and low temperatures, gas atmospheres poisonous to humans but where exotic microbes can flourish, highly acidic or salty fluids, heavy metals, and high background radiation levels. Some cave microorganisms eat their way through bedrock, some live in battery acid conditions, some produce unusual biominerals and rare cave formations, and many produce compounds of potential pharmaceutical and industrial significance. We study these unique lifeforms and the physical and chemical biosignatures that they leave behind. Such traces can be used to provide a "Field Guide to Unknown Organisms" for developing life detection space missions.

  2. Correlating multispectral imaging and compositional data from the Mars Exploration Rovers and implications for Mars Science Laboratory

    Science.gov (United States)

    Anderson, Ryan B.; Bell, James F.

    2013-01-01

    In an effort to infer compositional information about distant targets based on multispectral imaging data, we investigated methods of relating Mars Exploration Rover (MER) Pancam multispectral remote sensing observations to in situ alpha particle X-ray spectrometer (APXS)-derived elemental abundances and Mössbauer (MB)-derived abundances of Fe-bearing phases at the MER field sites in Gusev crater and Meridiani Planum. The majority of the partial correlation coefficients between these data sets were not statistically significant. Restricting the targets to those that were abraded by the rock abrasion tool (RAT) led to improved Pearson’s correlations, most notably between the red–blue ratio (673 nm/434 nm) and Fe3+-bearing phases, but partial correlations were not statistically significant. Partial Least Squares (PLS) calculations relating Pancam 11-color visible to near-IR (VNIR; ∼400–1000 nm) “spectra” to APXS and Mössbauer element or mineral abundances showed generally poor performance, although the presence of compositional outliers led to improved PLS results for data from Meridiani. When the Meridiani PLS model for pyroxene was tested by predicting the pyroxene content of Gusev targets, the results were poor, indicating that the PLS models for Meridiani are not applicable to data from other sites. Soft Independent Modeling of Class Analogy (SIMCA) classification of Gusev crater data showed mixed results. Of the 24 Gusev test regions of interest (ROIs) with known classes, 11 had >30% of the pixels in the ROI classified correctly, while others were mis-classified or unclassified. k-Means clustering of APXS and Mössbauer data was used to assign Meridiani targets to compositional classes. The clustering-derived classes corresponded to meaningful geologic and/or color unit differences, and SIMCA classification using these classes was somewhat successful, with >30% of pixels correctly classified in 9 of the 11 ROIs with known classes. This work shows

  3. Dust deposition on the Mars Exploration Rover Panoramic Camera (Pancam) calibration targets

    Science.gov (United States)

    Kinch, K.M.; Sohl-Dickstein, J.; Bell, J.F.; Johnson, J. R.; Goetz, W.; Landis, G.A.

    2007-01-01

    The Panoramic Camera (Pancam) on the Mars Exploration Rover mission has acquired in excess of 20,000 images of the Pancam calibration targets on the rovers. Analysis of this data set allows estimates of the rate of deposition and removal of aeolian dust on both rovers. During the first 150-170 sols there was gradual dust accumulation on the rovers but no evidence for dust removal. After that time there is ample evidence for both dust removal and dust deposition on both rover decks. We analyze data from early in both rover missions using a diffusive reflectance mixing model. Assuming a dust settling rate proportional to the atmospheric optical depth, we derive spectra of optically thick layers of airfall dust that are consistent with spectra from dusty regions on the Martian surface. Airfall dust reflectance at the Opportunity site appears greater than at the Spirit site, consistent with other observations. We estimate the optical depth of dust deposited on the Spirit calibration target by sol 150 to be 0.44 ?? 0.13. For Opportunity the value was 0.39 ?? 0.12. Assuming 80% pore space, we estimate that the dust layer grew at a rate of one grain diameter per ???100 sols on the Spirit calibration target. On Opportunity the rate was one grain diameter per ???125 sols. These numbers are consistent with dust deposition rates observed by Mars Pathfinder taking into account the lower atmospheric dust optical depth during the Mars Pathfinder mission. Copyright 2007 by the American Geophysical Union.

  4. Next generation laser-based standoff spectroscopy techniques for Mars exploration.

    Science.gov (United States)

    Gasda, Patrick J; Acosta-Maeda, Tayro E; Lucey, Paul G; Misra, Anupam K; Sharma, Shiv K; Taylor, G Jeffrey

    2015-01-01

    In the recent Mars 2020 Rover Science Definition Team Report, the National Aeronautics and Space Administration (NASA) has sought the capability to detect and identify elements, minerals, and most importantly, biosignatures, at fine scales for the preparation of a retrievable cache of samples. The current Mars rover, the Mars Science Laboratory Curiosity, has a remote laser-induced breakdown spectroscopy (LIBS) instrument, a type of quantitative elemental analysis, called the Chemistry Camera (ChemCam) that has shown that laser-induced spectroscopy instruments are not only feasible for space exploration, but are reliable and complementary to traditional elemental analysis instruments such as the Alpha Particle X-Ray Spectrometer. The superb track record of ChemCam has paved the way for other laser-induced spectroscopy instruments, such as Raman and fluorescence spectroscopy. We have developed a prototype remote LIBS-Raman-fluorescence instrument, Q-switched laser-induced time-resolved spectroscopy (QuaLITy), which is approximately 70 000 times more efficient at recording signals than a commercially available LIBS instrument. The increase in detection limits and sensitivity is due to our development of a directly coupled system, the use of an intensified charge-coupled device image detector, and a pulsed laser that allows for time-resolved measurements. We compare the LIBS capabilities of our system with an Ocean Optics spectrometer instrument at 7 m and 5 m distance. An increase in signal-to-noise ratio of at least an order of magnitude allows for greater quantitative analysis of the elements in a LIBS spectrum with 200-300 μm spatial resolution at 7 m, a Raman instrument capable of 1 mm spatial resolution at 3 m, and bioorganic fluorescence detection at longer distances. Thus, the new QuaLITy instrument fulfills all of the NASA expectations for proposed instruments.

  5. Scientific Investigations To Prepare For The Potential Human Exploration Of Mars

    Science.gov (United States)

    Hays, Lindsay; Beaty, David; Whitley, Ryan

    2016-07-01

    In order for human missions to the martian system to be successful and safe, we need a certain minimum set of knowledge. Comparison of what we need to know with what we already know defines what we refer to as "Strategic Knowledge Gaps (SKGs)". The SKG list needs to be the driving force behind the robotic precursor program. The Mars SKG list was first constructed by the Precursor Strategy Analysis Group (P-SAG) in 2012. It consisted of 17 SKGs that could be addressed by about 60 gap-filling activities (GFA). These GFAs were split into three groups based on where and how they could be carried out: requires a Mars flight/mission, addressed on Earth, or technology demonstration. Those GFAs that require a Mars mission were incorporated into the revision of the 2012 Goals Document of the Mars Exploration Program Analysis Group (MEPAG) as "investigations" under Goal IV: Prepare for Human Exploration. In 2015, MEPAG updated the Goals Document, and comparison of the 2012 and 2015 versions shows that significant and encouraging overall progress has been made on a number of the investigations. We note three specific kinds of changes: 1) Complete retirement of several investigations, 2) Decreased investigation priority based on partial progress, and 3) Addition of a few new investigations. Some of these changes are detailed below: Retired: • Simultaneous spectra of solar energetic particles in space and ion the surface • Spectra of galactic cosmic rays on the surface • Trace gas abundances • Determine traction/cohesion in martian regolith • Determine vertical variation in regolith • High spatial resolution maps of mineral composition and abundance • High spatial resolution maps of subsurface ice depth and concentration Decreased Priority: • Making long-term measurements of winds and wind directions (improvements in EDL technologies have decreased the importance of this measurement) • Profile the near-surface winds (improvements in EDL technologies have

  6. An alternative approach to solar system exploration providing safety of human mission to Mars.

    Science.gov (United States)

    Gitelson, J I; Bartsev, S I; Mezhevikin, V V; Okhonin, V A

    2003-01-01

    For systematic human Mars exploration, meeting crew safety requirements, it seems perspective to assemble into a spacecraft: an electrical rocket, a well-shielded long-term life support system, and a manipulator-robots operating in combined "presence effect" and "master-slave" mode. The electrical spacecraft would carry humans to the orbit of Mars, providing short distance (and low signal time delay) between operator and robot-manipulators, which are landed on the surface of the planet. Long-term hybrid biological and physical/chemical LSS could provide environment supporting human health and well being. Robot-manipulators operating in "presence effect" and "master-slave" mode exclude necessity of human landing on Martian surface decreasing the level of risk for crew. Since crewmen would not have direct contact with the Martian environment then the problem of mutual biological protection is essentially reduced. Lightweight robot-manipulators, without heavy life support systems and without the necessity of returning to the mother vessel, could be sent as scouts to different places on the planet surface, scanning the most interesting for exobiological research site. Some approximate estimations of electric spacecraft, long-term hybrid LSS, radiation protection and mission parameters are conducted and discussed. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  7. Nuclear propulsion: A vital technology for the exploration of Mars and the planets beyond

    Science.gov (United States)

    Borowski, Stanley K.

    1988-01-01

    The physics and technology issues and performance potential of various direct thrust fission and fusion propulsion concepts are examined. Next to chemical propulsion the solid core fission thermal rocket (SCR) is the olny other concept to be experimentally tested at the power (approx 1.5 to 5.0 GW) and thrust levels (approx 0.33 to 1.11 MN) required for manned Mars missions. With a specific impulse of approx 850 s, the SCR can perform various near-Earth, cislunar and interplanetary missions with lower mass and cost requirements than its chemical counterpart. The gas core fission thermal rocket, with a specific power and impulse of approx 50 kW/kg and 5000 s offers the potential for quick courier trips to Mars (of about 80 days) or longer duration exploration cargo missions (lasting about 280 days) with starting masses of about 1000 m tons. Convenient transportation to the outer Solar System will require the development of magnetic and inertial fusion rockets (IFRs). Possessing specific powers and impulses of approx 100 kW/kg and 200-300 kilosecs, IFRs will usher in the era of the true Solar System class speceship. Even Pluto will be accessible with roundtrip times of less than 2 years and starting masses of about 1500 m tons.

  8. Nuclear propulsion - A vital technology for the exploration of Mars and the planets beyond

    Science.gov (United States)

    Borowski, Stanley K.

    1989-01-01

    The physics and technology issues and performance potential of various direct thrust fission and fusion propulsion concepts are examined. Next to chemical propulsion the solid core fission thermal rocket (SCR) is the only other concept to be experimentally tested at the power (approx 1.5 to 5.0 GW) and thrust levels (approx 0.33 to 1.11 MN) required for manned Mars missions. With a specific impulse of approx 850 s, the SCR can perform various near-earth, cislunar and interplanetary missions with lower mass and cost requirements than its chemical counterpart. The gas core fission thermal rocket, with a specific power and impulse of approx 50 kW/kg and 5000 s offers the potential for quick courier trips to Mars (of about 80 days) or longer duration exploration cargo missions (lasting about 280 days) with starting masses of about 1000 m tons. Convenient transportation to the outer Solar System will require the development of magnetic and inertial fusion rockets (IFRs). Possessing specific powers and impulses of approx 100 kW/kg and 200-300 kilosecs, IFRs will usher in the era of the true Solar System class spaceship. Even Pluto will be accessible with roundtrip times of less than 2 years and starting masses of about 1500 m tons.

  9. Dynamic Modeling and Soil Mechanics for Path Planning of the Mars Exploration Rovers

    Science.gov (United States)

    Trease, Brian; Arvidson, Raymond; Lindemann, Randel; Bennett, Keith; Zhou, Feng; Iagnemma, Karl; Senatore, Carmine; Van Dyke, Lauren

    2011-01-01

    To help minimize risk of high sinkage and slippage during drives and to better understand soil properties and rover terramechanics from drive data, a multidisciplinary team was formed under the Mars Exploration Rover (MER) project to develop and utilize dynamic computer-based models for rover drives over realistic terrains. The resulting tool, named ARTEMIS (Adams-based Rover Terramechanics and Mobility Interaction Simulator), consists of the dynamic model, a library of terramechanics subroutines, and the high-resolution digital elevation maps of the Mars surface. A 200-element model of the rovers was developed and validated for drop tests before launch, using MSC-Adams dynamic modeling software. Newly modeled terrain-rover interactions include the rut-formation effect of deformable soils, using the classical Bekker-Wong implementation of compaction resistances and bull-dozing effects. The paper presents the details and implementation of the model with two case studies based on actual MER telemetry data. In its final form, ARTEMIS will be used in a predictive manner to assess terrain navigability and will become part of the overall effort in path planning and navigation for both Martian and lunar rovers.

  10. Overview of the magnetic properties experiments onboard the two Mars Exploration Rovers, Spirit and Opportunity

    Science.gov (United States)

    Leer, K.; Bertelsen, P.; Goetz, W.; Hviid, S. F.; Madsen, D. E.; Madsen, M. B.; Olsen, M.; The, A.

    2007-05-01

    The two Mars Exploration Rovers, Spirit and Opportunity, are each equipped with seven magnets designed for three different purposes: 1. The Filter and Capture magnets collect dust from the atmosphere. The dust can be investigated by the science instruments on the robotic arm and imaged by the Panoramic Camera. Analyzes of the dust shows that the magnetic component in the martian dust is magnetite, hematite together with paramagnetic and possibly superparamagnetic compounds is responsible for the yellowish color of the dust and the presence of olivine shows that the dust is formed without any appreciable presence of water. 2. The ring shaped Sweep magnet is design to detect non-magnetic particles. The experiment has been negative so far, showing that all particles must be composite and magnetic. This experience has been used to design a new camera calibration target for the Phoenix 2007, the sweep effect significantly preventing the calibration target to get dusty during the mission. 3. The Rock Abrasion Tool magnets are design to support the Mössbauer measurements on rocks giving additional information about the magnetic minerals contained in rocks. We here report on the results from the rovers and the neer future prospective for magnetic properties experiments on Mars.

  11. Conjoined Twins

    Science.gov (United States)

    ... sites of conjoined twins. Abdomen. Omphalopagus (om-fuh-LOP-uh-gus) twins are joined near the bellybutton. ... brain tissue. Head and chest. Cephalopagus (sef-uh-LOP-uh-gus) twins are joined at the face ...

  12. Mars Exploration: Is There Water on Mars? An Educator's Guide with Activities for Physical and Earth and Space Science.

    Science.gov (United States)

    TERC, Cambridge, MA.

    This educator's guide discusses whether there is water on the planet Mars. The activities, written for grades 9-12, concern physical, earth, and space sciences. By experimenting with water as it changes state and investigating some effects of air pressure, students not only learn core ideas in physical science but can also deduce the water…

  13. Nuclear Thermal Propulsion (NTP): A Proven Growth Technology for Human NEO/Mars Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    - the 25,000 lbf (25 klbf) "Pewee" engine is sufficient when used in a clustered engine arrangement. The "Copernicus" crewed spacecraft design developed in DRA 5.0 has significant capability and a human exploration strategy is outlined here that uses Copernicus and its key components for precursor near Earth object (NEO) and Mars orbital missions prior to a Mars landing mission. The paper also discusses NASA s current activities and future plans for NTP development that include system-level Technology Demonstrations - specifically ground testing a small, scalable NTR by 2020, with a flight test shortly thereafter.

  14. A Strategy to Integrate Probabilistic Risk Assessment into Design and Development Processes for Aerospace Based pon Mars Exploration Rover Experiences

    Science.gov (United States)

    Nunes, Jeffery; Paulos, Todd; Everline, Chester J.; Dezfuli, Homayoon

    2006-01-01

    This paper will discuss the Probabilistic Risk Assessment (PRA) effort and its involvement with related activities during the development of the Mars Exploration Rover (MER). The Rovers were launched 2003.June.10 (Spirit) and 2003.July.7 (Opportunity), and both have proven very successful. Although designed for a 90-day mission, the Rovers have been operating for over two earth years. This paper will review aspects of how the MER project integrated PRA into the design and development process. A companion paper (Development of the Mars Exploration Rover PRA) will describe the MER PRA and design changes from those results.

  15. Surplus weapons-grade plutonium: a resource for exploring and terraforming Mars

    Energy Technology Data Exchange (ETDEWEB)

    Muscatello, A.C.; Houts, M.G.

    1996-12-31

    With the end of the Cold War, greater than 100 metric tons (MT) of weapons-grade plutonium (WGPu) have become surplus to defense needs in the United States and the Former Soviet Union. This paper is a proposal for an option for WGPu disposition, i.e., use of the plutonium as a fuel for nuclear reactors for Mars exploration and eventual terraforming. WGPu was used in nuclear weapons because it has a much smaller critical mass than highly enriched uranium, allowing lighter weapons with consequent longer ranges. Similarly, WGPu reactors would also require smaller amounts of fuel to attain a critical mass, making the reactor much lighter overall and resulting in large savings in launch costs. The greater than 100 MT of WGPu would generate about 1000 billion kilowatt hours of heat energy, much of which could be converted into electricity. The waste heat would also be useful to a Martian outpost or colony. A potential way of getting the WGPu reactors into space is a large gas gun like that being developed at the Lawrence Livermore National Laboratory to orbit materials by achieving high velocity at the surface, greatly reducing launch costs and enhancing reliability. Reactor components would be launched on conventional rockets or space shuttles, the reactor fuel rods would be injected into orbit using the gas gun, and the reactor would be assembled in space. Implementation of this proposal would allow disposition of a serious, expensive problem on earth by removing the WGPu from the planet and simultaneously provide a very large energy resource for Mars exploration and terraforming.

  16. Principal Components Analysis of Reflectance Spectra Returned by the Mars Exploration Rover Opportunity

    Science.gov (United States)

    Mercer, C. M.; Cohen, Barbara A.

    2010-01-01

    The Mars Exploration Rover Opportunity has spent over six years exploring the Martian surface near its landing site at Meridiani Planum. Meridiani bedrock observed by the rover is largely characterized by sulfate-rich sandstones and hematite spherules, recording evidence of ancient aqueous environments [1]. The region is a deflationary surface, allowing hematite spherules, fragments of bedrock, and "cobbles" of foreign origin to collect loosely on the surface. These cobbles may be meteorites (e.g., Barberton, Heat Shield Rock, Santa Catarina) [2], or rock fragments of exotic composition derived from adjacent terranes or from the subsurface and delivered to Meridiani Planum as impact ejecta [3]. The cobbles provide a way to better understand Martian meteorites and the lithologic diversity of Meridiani Planum by examining the various rock types located there. In the summer of 2007, a global dust storm on Mars effectively disabled Opportunity's Miniature Thermal Emission Spectrometer (Mini-TES), which served as the Athena Science Team s primary tool for remotely identifying rocks of interest on a tactical timescale for efficient rover planning. While efforts are ongoing to recover use of the Mini-TES, the team is currently limited to identifying rocks of interest by visual inspection of images returned from Opportunity's Panoramic Camera (Pancam). This study builds off of previous efforts to characterize cobbles at Meridiani Planum using a database of reflectance spectra extracted from Pancam 13-Filter (13F) images [3]. We analyzed the variability of rock spectra in this database and identified physical characteristics of Martian rocks that could potentially account for the observed variance. By understanding such trends, we may be able to distinguish between rock types at Meridiani Planum and regain the capability to remotely identify locally unique rocks.

  17. Integration of an Earth-Based Science Team During Human Exploration of Mars

    Science.gov (United States)

    Chappell, Steven P.; Beaton, Kara H.; Newton, Carolyn; Graff, Trevor G.; Young, Kelsey E.; Coan, David; Abercromby, Andrew F. J.; Gernhardt, Michael L.

    2017-01-01

    NASA Extreme Environment Mission Operations (NEEMO) is an underwater spaceflight analog that allows a true mission-like operational environment and uses buoyancy effects and added weight to simulate different gravity levels. A mission was undertaken in 2016, NEEMO 21, at the Aquarius undersea research habitat. During the mission, the effects of varied oper-ations concepts with representative communication latencies as-sociated with Mars missions were studied. Six subjects were weighed out to simulate partial gravity and evaluated different operations concepts for integration and management of a simulated Earth-based science team (ST) who provided input and direction during exploration activities. Exploration traverses were planned in advance based on precursor data collected. Subjects completed science-related tasks including presampling surveys and marine-science-based sampling during saturation dives up to 4 hours in duration that simulated extravehicular activity (EVA) on Mars. A communication latency of 15 minutes in each direction between space and ground was simulated throughout the EVAs. Objective data included task completion times, total EVA time, crew idle time, translation time, ST assimilation time (defined as time available for the science team to discuss, to review and act upon data/imagery after they have been collected and transmitted to the ground). Subjective data included acceptability, simulation quality, capability assessment ratings, and comments. In addition, comments from both the crew and the ST were captured during the post-mission debrief. Here, we focus on the acceptability of the operations concepts studied and the capabilities most enhancing or enabling in the operations concept. The importance and challenges of designing EVA time-lines to account for the length of the task, level of interaction with the ground that is required/desired, and communication latency, are discussed.

  18. 火星探测的主要科学问题%Major scientific issues involved in Mars exploration

    Institute of Scientific and Technical Information of China (English)

    欧阳自远; 肖福根

    2011-01-01

    Among the planets of the solar system discovered so far, the similar features between the Mars and the Earth is the most prominent. Therefore, the Mars takes an important place in human's dreams. The issue about Mars water and life inspires the curiosity of exploring the Mars, and becomes a drive of successive Mars explorations. How did the Mars evolve and what is behind this evolution? What is the relationship between the evolutions of the Mars and the solar system? Can we make the Mars a green planet fit for sustainable human habitation and development? One must unveil these major scientific issues in the course of their Mars explorations. Only after these issues are solved one by one can we go on to think about the future of the Earth and mankind as related with the Mars.%在太阳系的行星中,火星与地球之间存在最多的相似之处,因此,火星是一颗承载人类最多梦想的星球.火星有水和生命存在的问题,激发了人类火星探索的好奇心,成为人类持续探测火星的推动力.火星的起源和演化与太阳系形成过程的关系,火星与类地行星的共性和特性,是当代行星科学研究的重要内容.为了人类社会的可持续发展,火星可否改造成为适宜人类居住的绿色星球--这些是人类在火星探测中必须面对的重大科学问题.只有这些重大科学问题被一一解答,我们才能清晰地去思考地球和人类自身的未来!

  19. "Dust Devils": Gardening Agents on the Surface of Mars, and Hidden Hazards to Human Exploration?

    Science.gov (United States)

    Marshall, J.; Smith, P.; White, B.; Farrell, W.

    1999-01-01

    Dust devils are familiar sites in the and regions of the world: they can produce quite spectacular displays of dust lofting when the vortices scavenge very loose dust from a dry lake bed or from recently disturbed agricultural fields. If one were to arrive at the center of an arid region, take one photograph, or even a series of photographs over a period of several days, then return the images for laboratory analysis, it would be most likely concluded that the region was inactive from an aeolian perspective. No images of general dust movement were obtained, nor were any dust devils "caught on camera" owing to their ephemeral and unpredictable appearance, and the fact that there was deceptively little residue of their actions. If, however, a camera were to take a 360 degree continuous recording over a period of a year, and the film were then to be shown at high speed over a period a several minutes, the impression might be that of a region ravaged by air vorticity and dust movement. Extrapolate this over geological time, and it is possible to visualize dust devils as prime aeolian agents, rather than insignificant vagaries of nature, On Mars, the thin atmosphere permits the surface of the planet to be heated but it does not itself retain heat with the capacity of the earth's atmosphere. This gives rise to greater thermal instability near the surface of Mars as "warm" air pockets diapiritically inject themselves into higher atmospheric layers. Resulting boundary-layer vorticity on Mars might therefore be expected to produce dust devils in abundance, if only seasonally. The spectacular images of dust devils obtained by Pathfinder within its brief functional period on the planet testify to the probability of highly frequent surface vorticity in light of the above reasoning about observational probability. Notably, the Pathfinder devils appeared to be at least a kilometer in height. There are several consequences for the geology of Mars, and for human exploration, if

  20. "Dust Devils": Gardening Agents on the Surface of Mars, and Hidden Hazards to Human Exploration?

    Science.gov (United States)

    Marshall, J.; Smith, P.; White, B.; Farrell, W.

    1999-09-01

    Dust devils are familiar sites in the and regions of the world: they can produce quite spectacular displays of dust lofting when the vortices scavenge very loose dust from a dry lake bed or from recently disturbed agricultural fields. If one were to arrive at the center of an arid region, take one photograph, or even a series of photographs over a period of several days, then return the images for laboratory analysis, it would be most likely concluded that the region was inactive from an aeolian perspective. No images of general dust movement were obtained, nor were any dust devils "caught on camera" owing to their ephemeral and unpredictable appearance, and the fact that there was deceptively little residue of their actions. If, however, a camera were to take a 360 degree continuous recording over a period of a year, and the film were then to be shown at high speed over a period a several minutes, the impression might be that of a region ravaged by air vorticity and dust movement. Extrapolate this over geological time, and it is possible to visualize dust devils as prime aeolian agents, rather than insignificant vagaries of nature, On Mars, the thin atmosphere permits the surface of the planet to be heated but it does not itself retain heat with the capacity of the earth's atmosphere. This gives rise to greater thermal instability near the surface of Mars as "warm" air pockets diapiritically inject themselves into higher atmospheric layers. Resulting boundary-layer vorticity on Mars might therefore be expected to produce dust devils in abundance, if only seasonally. The spectacular images of dust devils obtained by Pathfinder within its brief functional period on the planet testify to the probability of highly frequent surface vorticity in light of the above reasoning about observational probability. Notably, the Pathfinder devils appeared to be at least a kilometer in height. There are several consequences for the geology of Mars, and for human exploration, if

  1. "Dust Devils": Gardening Agents on the Surface of Mars, and Hidden Hazards to Human Exploration?

    Science.gov (United States)

    Marshall, J.; Smith, P.; White, B.; Farrell, W.

    1999-01-01

    Dust devils are familiar sites in the and regions of the world: they can produce quite spectacular displays of dust lofting when the vortices scavenge very loose dust from a dry lake bed or from recently disturbed agricultural fields. If one were to arrive at the center of an arid region, take one photograph, or even a series of photographs over a period of several days, then return the images for laboratory analysis, it would be most likely concluded that the region was inactive from an aeolian perspective. No images of general dust movement were obtained, nor were any dust devils "caught on camera" owing to their ephemeral and unpredictable appearance, and the fact that there was deceptively little residue of their actions. If, however, a camera were to take a 360 degree continuous recording over a period of a year, and the film were then to be shown at high speed over a period a several minutes, the impression might be that of a region ravaged by air vorticity and dust movement. Extrapolate this over geological time, and it is possible to visualize dust devils as prime aeolian agents, rather than insignificant vagaries of nature, On Mars, the thin atmosphere permits the surface of the planet to be heated but it does not itself retain heat with the capacity of the earth's atmosphere. This gives rise to greater thermal instability near the surface of Mars as "warm" air pockets diapiritically inject themselves into higher atmospheric layers. Resulting boundary-layer vorticity on Mars might therefore be expected to produce dust devils in abundance, if only seasonally. The spectacular images of dust devils obtained by Pathfinder within its brief functional period on the planet testify to the probability of highly frequent surface vorticity in light of the above reasoning about observational probability. Notably, the Pathfinder devils appeared to be at least a kilometer in height. There are several consequences for the geology of Mars, and for human exploration, if

  2. The Aerial Regional-Scale Environmental Surveyor (ARES): New Mars Science to Reduce Human Risk and Prepare for the Human Exploration

    Science.gov (United States)

    Levine, Joel S.; Croom, Mark A.; Wright, Henry S.; Killough, B. D.; Edwards, W. C.

    2012-01-01

    Obtaining critical measurements for eventual human Mars missions while expanding upon recent Mars scientific discoveries and deriving new scientific knowledge from a unique near surface vantage point is the focus of the Aerial Regional-scale Environmental Surveyor (ARES) exploration mission. The key element of ARES is an instrumented,rocket-powered, well-tested robotic airplane platform, that will fly between one to two kilometers above the surface while traversing hundreds of kilometers to collect and transmit previously unobtainable high spatial measurements relevant to the NASA Mars Exploration Program and the exploration of Mars by humans.

  3. A geoethical approach to the geological and astrobiological exploration and research of the Moon and Mars

    Science.gov (United States)

    Martinez-Frias, Jesus; Horneck, Gerda; de La Torre Noetzel, Rosa; Rull, Fernando

    Lunar and Mars exploration and research require not only scientific and technological inter-disciplinary cooperation, but also the consideration of budding ethical and scientific integrity issues. COSPAR's planetary protection policy (in coordination with the United Nations Com-mittee on the Peaceful Uses of Outer Space as well as various other bilateral and multilateral organizations) serves as the consensus standard for biological contamination prevention under the 1967 Outer Space Treaty1 . Space agencies Planetary Protection Policies are mostly consis-tent with the COSPAR policy. Geoethics was formerly promoted in 1991 as a new discipline, involving scientific and societal aspects2 , and its institutionalization was officially established in 2004 with the backing of the Association of Geoscientists for International Development, AGID3 (IUGS/ICSU). Recently, it has been proposed that the integration of geoethical issues in studies on planetary geology and astrobiology would enrich their methodological and con-ceptual character4-6 . The incorporation through geoethics of new questions and approaches associated to the "abiotic world" would involve: 1) extrapolating to space the recently defined and approved IUCN/UNESCO guidelines and recommendations on geodiversity7 as "planetary geodiversity", and 2) widening the classical concept of Planetary Protection, giving an addi-tional "abiotic" dimension to the exploration and research of the Moon and Mars. Given the geological characteristics and planetary evolution of the Moon and Mars, it is obvious that they require tailored geoethical approaches. Some fundamental aspects include, among others: the interrelation with bioethics and organics vs. inorganic contamination in Planetary Protection, the appropriate regulations of some necessary natural disturbances (e.g. on the Moon) dur-ing robotic and manned planetary missions, wilderness/planetary parks8,9 , the correct use of mineralogical and geochemical analytical

  4. Cell biology and biotechnology research for exploration of the Moon and Mars

    Science.gov (United States)

    Pellis, N.; North, R.

    Health risks generated by human long exposure to radiation, microgravity, and unknown factors in the planetary environment are the major unresolved issues for human space exploration. A complete characterization of human and other biological systems adaptation processes to long-duration space missions is necessary for the development of countermeasures. The utilization of cell and engineered tissue cultures in space research and exploration complements research in human, animal, and plant subjects. We can bring a small number of humans, animals, or plants to the ISS, Moon, and Mars. However, we can investigate millions of their cells during these missions. Furthermore, many experiments can not be performed on humans, e.g. radiation exposure, cardiac muscle. Cells from critical tissues and tissue constructs per se are excellent subjects for experiments that address underlying mechanisms important to countermeasures. The development of cell tissue engineered for replacement, implantation of biomaterial to induce tissue regeneration (e.g. absorbable collagen matrix for guiding tissue regeneration in periodontal surgery), and immunoisolation (e.g. biopolymer coating on transplanted tissues to ward off immunological rejection) are good examples of cell research and biotechnology applications. NASA Cell Biology and Biotechnology research include Bone/Muscle and Cardiovascular cell culture and tissue engineering; Environmental Health and Life Support Systems; Immune System; Radiation; Gravity Thresholds ; and Advanced Biotechnology Development to increase the understanding of animal and plant cell adaptive behavior when exposed to space, and to advance technologies that facilitates exploration. Cell systems can be used to investigate processes related to food, microbial proliferation, waste management, biofilms and biomaterials. The NASA Cell Science Program has the advantage of conducting research in microgravity based on significantly small resources, and the ability to

  5. Exploring how nature and nurture affect the development of reading: An analysis of the Florida Twin Project on Reading

    Science.gov (United States)

    Hart, Sara A.; Logan, Jessica A.R.; Soden-Hensler, Brooke; Kershaw, Sarah; Taylor, Jeanette; Schatschneider, Christopher

    2013-01-01

    Research on the development of reading skills through the primary school years has pointed to the importance of individual differences in initial ability as well as the growth of those skills. Additionally, it has been theorized that reading skills develop incrementally. The present study examined the genetic and environmental influences on two developmental models representing these parallel ideas, generalizing the findings to explore the processes of reading development. Participants were drawn from the Florida Twin Project on Reading, with a total of 2370 pairs of twins’ representative of the state of Florida. Twins’ oral reading fluency scores from school progress monitoring records collected in the fall of grades 1 through 5 were used to model development. Results suggested that genetic influences on the development of reading are general, shared across the early school years, as well as novel, with new genetic influences introduced at each of the first three years of school. The shared environment estimates suggest a pattern of general influences only, suggesting environmental effects which are moderate and stable across development. PMID:23294149

  6. Mission Assurance and Flight Safety of Manned Space Flight: Implications for Future Exploration of the Moon and Mars

    Science.gov (United States)

    Kezirian, M. T.

    2007-01-01

    As NASA implements the nation's Vision for Space Exploration to return to the moon and travel to Mars, new considerations will be be given to the processes governing design and operations of manned spaceflight. New objectives bring new technical challenges; Safety will drive many of these decisions.

  7. ACARDIAC TWIN

    OpenAIRE

    Vinayachandran; Jyothi,; Bindu; Umadevi

    2014-01-01

    Acardiac twin is a very rare complication occurring in monozygotic twins in which one fetus develops normally (pump twin) and the other (recipient twin) demonstrate cardiac non development and othe r anomalies. This may represent an extreme form of TTTS, also referred to as TRAP sequence. 1,2,

  8. Parametric study of the factors affecting wheel slip and sinkage for the Mars Exploration Rovers

    Science.gov (United States)

    Johnson, J.; Kulchitsky, A. V.; Duvoy, P.; Arvidson, R. E.; Iagnemma, K.; Senatore, C.

    2013-12-01

    In 2004 two rovers landed on Mars to conduct scientific investigations of the Martian surface in an effort to better understand its surface geology, climate, and potential to support life. During the mission, both rovers experienced events of severe rover wheel sinkage and slip in the highly variable Martian regolith. Mars Exploration Rover (MER) Opportunity experienced high wheel slip and sinkage when it attempted to cross a series of wind-blown ripples. MER rover Spirit became immobilized after breaking through a soil crust into highly deformable poorly sorted sands. Events of MER rover wheel high-sinkage and slip make mobility difficult, creating challenges for rover drive planners and increasing the risk of ending a mission early due to a lack of rover mobility. The ARTEMIS (Adams- based Rover Terramechanics and Mobility Interaction Simulator) MER rover simulation tool was developed in an effort to improve the ability to simulate rover mobility on planetary surfaces to aid planning of rover drives and to extract a rover if it becomes embedded in soil [1]. While ARTEMIS has demonstrated its ability to simulate a wide variety of rover mobility scenarios using a library of empirically based terramechanics subroutines and high-resolution digital elevation maps of Mars, it has had less success at simulating the high-sinkage, high-slip conditions that pose the highest risk to rover mobility. To improve ARTEMIS's high-slip, high-sinkage terramechanics subroutines, the COUPi discrete element method (DEM) model of MER rover wheel motion under conditions of high-sinkage and slip is being used to examine the effects of soil particle size distribution (PSD), shape, and bulk density. DEM simulations of MER wheel digging tests and the resistance forces of penetrometers in soil have demonstrated the importance of particle shape and bulk density on soil strength [2, 3]. Simulations of the densification of particle beds as functions of the spread (ratio of largest to smallest

  9. Conceptual Design and Architecture of Mars Exploration Rover (MER) for Seismic Experiments Over Martian Surfaces

    Science.gov (United States)

    Garg, Akshay; Singh, Amit

    2012-07-01

    Keywords: MER, Mars, Rover, Seismometer Mars has been a subject of human interest for exploration missions for quite some time now. Both rover as well as orbiter missions have been employed to suit mission objectives. Rovers have been preferentially deployed for close range reconnaissance and detailed experimentation with highest accuracy. However, it is essential to strike a balance between the chosen science objectives and the rover operations as a whole. The objective of this proposed mechanism is to design a vehicle (MER) to carry out seismic studies over Martian surface. The conceptual design consists of three units i.e. Mother Rover as a Surrogate (Carrier) and Baby Rovers (two) as seeders for several MEMS-based accelerometer / seismometer units (Nodes). Mother Rover can carry these Baby Rovers, having individual power supply with solar cells and with individual data transmission capabilities, to suitable sites such as Chasma associated with Valles Marineris, Craters or Sand Dunes. Mother rover deploys these rovers in two opposite direction and these rovers follow a triangulation pattern to study shock waves generated through firing tungsten carbide shells into the ground. Till the time of active experiments Mother Rover would act as a guiding unit to control spatial spread of detection instruments. After active shock experimentation, the babies can still act as passive seismometer units to study and record passive shocks from thermal quakes, impact cratering & landslides. Further other experiments / payloads (XPS / GAP / APXS) can also be carried by Mother Rover. Secondary power system consisting of batteries can also be utilized for carrying out further experiments over shallow valley surfaces. The whole arrangement is conceptually expected to increase the accuracy of measurements (through concurrent readings) and prolong life cycle of overall experimentation. The proposed rover can be customised according to the associated scientific objectives and further

  10. A method to evaluate utility for architectural comparisons for a campaign to explore the surface of Mars

    Science.gov (United States)

    Ward, Eric D.; Webb, Ryan R.; deWeck, Olivier L.

    2016-11-01

    There is a general consensus that Mars is the next high priority destination for human space exploration. There has been no lack of analysis and recommendations for human missions to Mars, including, for example, the NASA Design Reference Architectures and the Mars Direct proposal. These studies and others usually employ the traditional approach of selecting a baseline mission architecture and running individual trade studies. However, this can cause blind spots, as not all combinations are explored. An alternative approach is to holistically analyze the entire architectural trade-space such that all of the possible system interactions are identified and measured. In such a framework, an optimal design is sought by minimizing cost for maximal value. While cost is relatively easy to model for manned spaceflight, value is more difficult to define. In our efforts to develop a surface base architecture for the MIT Mars 2040 project, we explored several methods for quantifying value, including technology development benefits, challenge, and various metrics for measuring scientific return. We developed a science multi-score method that combines astrobiology and geologic research goals, which is weighted by the crew-member hours that can be used for scientific research rather than other activities.

  11. On the Raman Detectability of Biomarkers in Geological Matrices in preparation for Mars Exploration

    Science.gov (United States)

    Malherbe, Cedric; Hutchinson, Ian B.; DEMARET, Lucas; INGLEY, Richard; EDWARDS, Howell G. M.; EPPE, Gauthier; ExoMars Raman Team at the University of Leicester, Group of Inorganic Analytical Chemsitry at the University of Liege

    2016-10-01

    In 2020, Raman spectrometers will be launched to Mars as part of the ESA/ROSCOSMOS's ExoMars 2020 mission and the NASA's Mars 2020 mission. The miniaturized Raman instrument on board the ExoMars rover has two scientific goals: characterize the geochemistry of the surface and subsurface of Mars, and search for molecular evidence of past and present life. Raman spectrometers have indeed the capability to characterize non-destructively the geology of the rocky surface of Mars. Information on the nature and the molecular composition of the surface and subsurface of Mars will provide valuable information about the habitability of the red planet. In addition, Raman spectrometers have the ability to detect potential molecular biomarkers which are substances obtained by biochemical processes or their derivatives preserved in a protective geological niche. In preparation for Mars mission, studying the detection capability of miniaturized Raman spectrometers (specifically developed for space missions and therefore compromised by the associated challenging constraints) is highly important, on both lab synthetic samples and natural terrestrial analogues samples. We present here an analytical strategy to determine the limit of detection achievable based on Raman spectral images. Raman data were recorded with benchtop instruments and a Raman Laser Spectrometer prototype developed at the University of Leicester to optimize/characterize the camera system that will be used for the ExoMars mission.

  12. Results of the Alpha-Particle-X-Ray Spectrometer on Board of the Mars Exploration Rovers

    Science.gov (United States)

    Geller, R.; Zipfel, J.; Brueckner, J.; Dreibus, G.; Lugmair, G.; Rieder, R.; Waenke, H.; Klingelhoefer, G.; Clark, B. C.; Ming, D. W.

    2005-01-01

    The Mars Exploration Rovers Spirit and Opportunity landed at Gusev crater and Meridiani Planum. The Alpha Particle X-ray Spectrometer (APXS) is part of the instrument suite on both rovers. It is equipped with six 244Cm sources which provide x-ray excitation with alpha-particles (PIXE) and x-ray radiation (XRF). This combination allows x-ray spectroscopy of elements from Na to Br in the energy range of 0.9 to 16 keV. X-ray detectors with a high energy resolution of 160 eV at Fe K allow us to separate even closely spaced energy peaks, such as Na, Mg, Al and Si. The APXS is attached to the rover s arm and provides in-situ measurements of the chemical composition of soils, surfaces of rocks and outcrops and their abraded surfaces. This abstract gives an overview of APXS results obtained during the first year of operation on both landing sites.

  13. Review of NASA approach to space radiation risk assessments for Mars exploration.

    Science.gov (United States)

    Cucinotta, Francis A

    2015-02-01

    Long duration space missions present unique radiation protection challenges due to the complexity of the space radiation environment, which includes high charge and energy particles and other highly ionizing radiation such as neutrons. Based on a recommendation by the National Council on Radiation Protection and Measurements, a 3% lifetime risk of exposure-induced death for cancer has been used as a basis for risk limitation by the National Aeronautics and Space Administration (NASA) for low-Earth orbit missions. NASA has developed a risk-based approach to radiation exposure limits that accounts for individual factors (age, gender, and smoking history) and assesses the uncertainties in risk estimates. New radiation quality factors with associated probability distribution functions to represent the quality factor's uncertainty have been developed based on track structure models and recent radiobiology data for high charge and energy particles. The current radiation dose limits are reviewed for spaceflight and the various qualitative and quantitative uncertainties that impact the risk of exposure-induced death estimates using the NASA Space Cancer Risk (NSCR) model. NSCR estimates of the number of "safe days" in deep space to be within exposure limits and risk estimates for a Mars exploration mission are described.

  14. Risk Assessment of Bone Fracture During Space Exploration Missions to the Moon and Mars

    Science.gov (United States)

    Lewandowski, Beth E.; Myers, Jerry G.; Nelson, Emily S.; Griffin, Devon

    2008-01-01

    The possibility of a traumatic bone fracture in space is a concern due to the observed decrease in astronaut bone mineral density (BMD) during spaceflight and because of the physical demands of the mission. The Bone Fracture Risk Module (BFxRM) was developed to quantify the probability of fracture at the femoral neck and lumbar spine during space exploration missions. The BFxRM is scenario-based, providing predictions for specific activities or events during a particular space mission. The key elements of the BFxRM are the mission parameters, the biomechanical loading models, the bone loss and fracture models and the incidence rate of the activity or event. Uncertainties in the model parameters arise due to variations within the population and unknowns associated with the effects of the space environment. Consequently, parameter distributions were used in Monte Carlo simulations to obtain an estimate of fracture probability under real mission scenarios. The model predicts an increase in the probability of fracture as the mission length increases and fracture is more likely in the higher gravitational field of Mars than on the moon. The resulting probability predictions and sensitivity analyses of the BFxRM can be used as an engineering tool for mission operation and resource planning in order to mitigate the risk of bone fracture in space.

  15. Overview of the magnetic properties experiments on the Mars Exploration Rovers

    Science.gov (United States)

    Madsen, M.B.; Goetz, W.; Bertelsen, P.; Binau, C.S.; Folkmann, F.; Gunnlaugsson, H.P.; Hjollum, J.I.; Hviid, S.F.; Jensen, J.; Kinch, K.M.; Leer, K.; Madsen, D.E.; Merrison, J.; Olsen, M.; Arneson, H.M.; Bell, J.F.; Gellert, Ralf; Herkenhoff, K. E.; Johnson, J. R.; Johnson, M.J.; Klingelhofer, G.; McCartney, E.; Ming, D. W.; Morris, R.V.; Proton, J.B.; Rodionov, D.; Sims, M.; Squyres, S. W.; Wdowiak, T.; Yen, A. S.

    2009-01-01

    The Mars Exploration Rovers have accumulated airborne dust on different types of permanent magnets. Images of these magnets document the dynamics of dust capture and removal over time. The strongly magnetic subset of airborne dust appears dark brown to black in Panoramic Camera (Pancam) images, while the weakly magnetic one is bright red. Images returned by the Microscopic Imager reveal the formation of magnetic chains diagnostic of magnetite-rich grains with substantial magnetization (>8 Am2 kg-1). On the basis of M??ssbauer spectra the dust contains magnetite, olivine, pyroxene, and nanophase oxides in varying proportions, depending on wind regime and landing site. The dust contains a larger amount of ferric iron (Fe3+/Fe tot ??? 0.6) than rocks in the Gusev plains (???0.1-0.2) or average Gusev soil (???0.3). Alpha Particle X-Ray Spectrometer data of the dust show that some of the iron in magnetite is substituted by titanium and chromium. The good correlation of the amount of calcium and sulfur in the dust may be caused by the presence of a calcium sulfate related phase. The overall mineralogical composition points to a basaltic origin of the airborne dust, although some alteration has taken place as indicated by the large degree of oxidation. Copyright 2009 by the American Geophysical Union.

  16. Curiosity explores the base of Aeolis Mons, Gale crater, Mars: Recent Geological and Geochemical Mission Results

    Science.gov (United States)

    Gupta, Sanjeev; Vasavada, Ashwin; Crisp, Joy; Grotzinger, John

    2016-04-01

    The Mars Science Laboratory (MSL) Curiosity rover has been exploring sedimentary rocks at the foothills of Aolis Mons since August 2014. Here, an array of fluvial, lacustrine and aeolian strata that show a complex pattern of post-depositional alteration are present. This presentation will summarize the most recent geological and geochemical findings of the MSL mission. Basal outcrops that form the lowest stratigraphic unit of Aeolis Mons, the Murray formation, are characterized predominantly by mudstones with minor intercalated sandstones. The mudstone facies, originally identified at the Pahrump Hills field site, show abundant fine-scale planar laminations throughout the Murray formation succession and is interpreted to record deposition in an ancient lacustrine system in Gale crater. Interbedded cross-stratified sandstones are considered to record fluvio-deltaic incursions into the lake. The lacustrine deposits of the Murray formation are unconformably overlain by much younger sandstones of the Stimson formation. Orbital mapping and in situ observations indicate that the basal strata of the Stimson formation show complex onlap relationships with the underlying Murray formation strata signifying that there was metre-scale palaeotopographic relief on the unconformity surface upon which the Stimson accumulated. The Stimson formation itself is characterized by cross-bedded sandstones with cross-bed sets tens of centimetres in thickness. Sedimentological observations suggest that the Stimson dominantly records deposition by aeolian dunes. Curiosity has made detailed measurements of the geochemistry of the Murray and Stimson formations and associated diagenetic features. Perhaps most surprising has been the discovery of extensive silica enrichment both within mudstones of the Murray formation, perhaps of primary sedimentary or later diagenetic origin, also in as fracture-related diagenetic halos within the Stimson formation. We will describe the nature of this silica

  17. Growing crops for space explorers on the moon, Mars, or in space.

    Science.gov (United States)

    Salisbury, F B

    1999-01-01

    An option in the long-duration exploration of space, whether on the Moon or Mars or in a spacecraft on its way to Mars or the asteroids, is to utilize a bioregenerative life-support system in addition to the physicochemical systems that will always be necessary. Green plants can use the energy of light to remove carbon dioxide from the atmosphere and add oxygen to it while at the same time synthesizing food for the space travelers. The water that crop plants transpire can be condensed in pure form, contributing to the water purification system. An added bonus is that green plants provide a familiar environment for humans far from their home planet. The down side is that such a bioregenerative life-support system--called a controlled environment life-support system (CELSS) in this paper--must be highly complex and relatively massive to maintain a proper composition of the atmosphere while also providing food. Thus, launch costs will be high. Except for resupply and removal of nonrecycleable substances, such a system is nearly closed with respect to matter but open with respect to energy. Although a CELSS facility is small compared to the Earth's biosphere, it must be large enough to feed humans and provide a suitable atmosphere for them. A functioning CELSS can only be created with the help of today's advanced technology, especially computerized controls. Needed are energy for light, possibly from a nuclear power plant, and equipment to provide a suitable environment for plant growth, including a way to supply plants with the necessary mineral nutrients. All this constitutes the biomass production unit. There must also be food preparation facilities and a means to recycle or dispose of waste materials and there must be control equipment to keep the facility running. Humans are part of the system as well as plants and possibly animals. Human brain power will often be needed to keep the system functional in spite of the best computer-driven controls. The particulars

  18. Growing crops for space explorers on the moon, Mars, or in space

    Science.gov (United States)

    Salisbury, F. B.

    1999-01-01

    An option in the long-duration exploration of space, whether on the Moon or Mars or in a spacecraft on its way to Mars or the asteroids, is to utilize a bioregenerative life-support system in addition to the physicochemical systems that will always be necessary. Green plants can use the energy of light to remove carbon dioxide from the atmosphere and add oxygen to it while at the same time synthesizing food for the space travelers. The water that crop plants transpire can be condensed in pure form, contributing to the water purification system. An added bonus is that green plants provide a familiar environment for humans far from their home planet. The down side is that such a bioregenerative life-support system--called a controlled environment life-support system (CELSS) in this paper--must be highly complex and relatively massive to maintain a proper composition of the atmosphere while also providing food. Thus, launch costs will be high. Except for resupply and removal of nonrecycleable substances, such a system is nearly closed with respect to matter but open with respect to energy. Although a CELSS facility is small compared to the Earth's biosphere, it must be large enough to feed humans and provide a suitable atmosphere for them. A functioning CELSS can only be created with the help of today's advanced technology, especially computerized controls. Needed are energy for light, possibly from a nuclear power plant, and equipment to provide a suitable environment for plant growth, including a way to supply plants with the necessary mineral nutrients. All this constitutes the biomass production unit. There must also be food preparation facilities and a means to recycle or dispose of waste materials and there must be control equipment to keep the facility running. Humans are part of the system as well as plants and possibly animals. Human brain power will often be needed to keep the system functional in spite of the best computer-driven controls. The particulars

  19. HRSCview: a web-based data exploration system for the Mars Express HRSC instrument

    Science.gov (United States)

    Michael, G.; Walter, S.; Neukum, G.

    2007-08-01

    The High Resolution Stereo Camera (HRSC) on the ESA Mars Express spacecraft has been orbiting Mars since January 2004. By spring 2007 it had returned around 2 terabytes of image data, covering around 35% of the Martian surface in stereo and colour at a resolu-tion of 10-20 m/pixel. HRSCview provides a rapid means to explore these images up to their full resolu-tion with the data-subsetting, sub-sampling, stretching and compositing being carried out on-the-fly by the image server. It is a joint website of the Free University of Berlin and the German Aerospace Center (DLR). The system operates by on-the-fly processing of the six HRSC level-4 image products: the map-projected ortho-rectified nadir pan-chromatic and four colour channels, and the stereo-derived DTM (digital terrain model). The user generates a request via the web-page for an image with several parameters: the centre of the view in surface coordinates, the image resolution in metres/pixel, the image dimensions, and one of several colour modes. If there is HRSC coverage at the given location, the necessary segments are extracted from the full orbit images, resampled to the required resolution, and composited according to the user's choice. In all modes the nadir channel, which has the highest resolu-tion, is included in the composite so that the maximum detail is always retained. The images are stretched ac-cording to the current view: this applies to the eleva-tion colour scale, as well as the nadir brightness and the colour channels. There are modes for raw colour, stretched colour, enhanced colour (exaggerated colour differences), and a synthetic 'Mars-like' colour stretch. A colour ratio mode is given as an alternative way to examine colour differences (R=IR/R, G=R/G and B=G/B). The final image is packaged as a JPEG file and returned to the user over the web. Each request requires approximately 1 second to process. A link is provided from each view to a data product page, where header items describing

  20. What We Might Know About Gusev Crater if the Mars Exploration Rover Spirit Mission were Coupled with a Mars Sample Return Mission

    Science.gov (United States)

    Morris, Richard V.

    2008-01-01

    The science instruments on the Mars Exploration Rover (MER) Spirit have provided an enormous amount of chemical and mineralogical data during more than 1450 sols of exploration at Gusev crater. The Moessbauer (MB) instrument identified 10 Fe-bearing phases at Gusev Crater: olivine, pyroxene, ilmenite, chromite, and magnetite as primary igneous phases and nanophase ferric oxide (npOx), goethite, hematite, a ferric sulfate, and pyrite/marcusite as secondary phases. The Miniature Thermal Emission Spectrometer (Mini-TES) identified some of these Fe-bearing phases (olivine and pyroxene), non- Fe-bearing phases (e.g., feldspar), and an amorphous high-SiO2 phase near Home Plate. Chemical data from the Alpha Particle X-Ray Spectrometer (APXS) provided the framework for rock classification, chemical weathering/alteration, and mineralogical constraints. APXS-based mineralogical constraints include normative calculations (with Fe(3+)/FeT from MB), elemental associations, and stoichiometry (e.g., 90% SiO2 implicates opalline silica). If Spirit had cached a set of representative samples and if those samples were returned to the Earth for laboratory analysis, what value is added by Mars Sample return (MSR) over and above the mineralogical and chemical data provided by MER?

  1. Nuclear Thermal Rocket/Stage Technology Options for NASA's Future Human Exploration Missions to the Moon and Mars

    Science.gov (United States)

    Borowski, Stanley K.; Corban, Robert R.; McGuire, Melissa L.; Beke, Erik G.

    1994-07-01

    The nuclear thermal rocket (NTR) provides a unique propulsion capability to planners and designers of future human exploration missions to the Moon and Mars. In addition to its high specific impulse (Isp ~ 850-1000 seconds) and engine thrust-to-weight ratio (~ 3-10), the NTR can also be configured as a ``dual mode'' system capable of generating stage electrical power. At present, NASA is examining a variety of mission applications for the NTR ranging from an expendable, ``single burn'' trans-lunar injection (TLI) stage for NASA's ``First Lunar Outpost'' (FLO) mission to all propulsive, ``multi-burn,'' spacecraft supporting a ``split cargo/piloted sprint'' Mars mission architecture. Two ``proven'' solid core NTR concepts are examined -one based on NERVA (Nuclear Engine for Rocket Vehicle Application)-derivative reactor (NDR) technology, and a second concept which utilizes a ternary carbide ``twisted ribbon'' fuel form developed by the Commonwealth of Independent States (CIS). Integrated systems and mission study results are used in designing ``aerobraked'' and ``all propulsive'' Mars vehicle concepts which are mass-, and volume-compatible with both a reference 240 metric tonne (t) heavy lift launch vehicle (HLLV) and a smaller 120 t HLLV option. For the ``aerobraked'' scenario, the 2010 piloted mission determines the size of the expendable trans-Mars injection (TMI) stage which is a growth version of the FLO TLI stage. An ``all-propulsive'' Moon/Mars mission architecture is also described which uses common ``modular'' engine and stage hardware consisting of: (1) clustered 15 thousand pounds force (klbf) NDR or CIS engines; (2) two ``standardized'' liquid hydrogen (LH2) tank sizes; and (3) ``dual mode'' NTR and refrigeration system technologies for long duration missions. The ``modular'' NTR approach can form the basis for a ``faster, safer, and cheaper'' space transportation system for tomorrow's piloted missions to the Moon and Mars.

  2. Twin births

    DEFF Research Database (Denmark)

    Hoffmann, Elise; Oldenburg, Anna; Rode, Line;

    2012-01-01

    To assess morbidity and mortality in twin pregnancy deliveries, according to chorionicity and mode of delivery.......To assess morbidity and mortality in twin pregnancy deliveries, according to chorionicity and mode of delivery....

  3. Transformation: From Twin to Individual

    Science.gov (United States)

    Magagna, Jeanne

    2007-01-01

    This article explores some of the complexities of psychotherapy with an identical twin. The difficulty of developing in psychotherapy while so much of what is oneself is located in the other twin will also be explored. The use of the countertransference as a therapeutic method will be considered as the young person develops her unique, separate…

  4. Strategies for Prospecting and Extracting Water on Mars for Long-Term Human Exploration

    Science.gov (United States)

    Rolley, R. J.; Saikia, S. J.

    2017-02-01

    We aim to develop a specific set of criteria to classify water reserves on Mars, and to design water prospecting and extraction systems for various human landing sites using a requirements-driven framework.

  5. Ice Dragon: A Mission to Address Science and Human Exploration Objectives on Mars

    Science.gov (United States)

    Stoker, C.; Davilla, A.; Davis, S.; Glass, B.; Gonzales, A.; Heldmann, J.; Karcz, J.; Lemke, L.; Sanders, G.

    2012-06-01

    We present a mission concept where a SpaceX Dragon capsule lands a payload on Mars that samples ground ice to search for evidence of life, assess hazards to future human missions, and demonstrate use of Martian resources.

  6. Exploring PV on the Red Planet: Mars Array Technology Experiment and Dust Accumulation and Removal Technology

    Science.gov (United States)

    Landis, Geoffrey A.; Baraona, Cosmo; Brinker, David; Schelman, David

    2004-01-01

    The environment on the surface of Mars is different in several critical ways from the orbital environment in which space solar arrays normally operate. Some important differences are: 1) Low intensity, low temperature operation; 2) Spectrum modified by atmospheric dust, varies with time; 3) Indirect sunlight; 4) Possibility of dust atoms at some times of year; 5) Deposited dust; 6) Wind; 7) Peroxide-rich reactive soil. We are developing two experiments to test operation of solar arrays on the surface of Mars, to be flown on the 2001 Surveyor Lander mission. The Mars Array Technology Experiment (MATE) will test the operation of several types of solar cells under Mars conditions, and determine the direct and scattered solar spectrum at the surface. The Dust Accumulation and Removal Technology (DART) experiment will monitor the amount of dust deposition on a target solar cell, measure the characteristics of the dust, and test the feasibility of dust removal.

  7. Exploring the association between severe respiratory syncytial virus infection and asthma: a registry-based twin study

    DEFF Research Database (Denmark)

    Thomsen, Simon Francis; van der Sluis, Sophie; Stensballe, Lone G;

    2009-01-01

    RATIONALE: Severe respiratory syncytial virus (RSV) infection is associated with asthma but the nature of this association is imperfectly understood. OBJECTIVES: To examine the nature of the association between severe RSV infection and asthma in a population-based sample of twins. METHODS: Data...

  8. Design of Photovoltaic Power System for a Precursor Mission for Human Exploration of Mars

    Science.gov (United States)

    Mcnatt, Jeremiah; Landis, Geoffrey; Fincannon, James

    2016-01-01

    This project analyzed the viability of a photovoltaic power source for technology demonstration mission to demonstrate Mars in-situ resource utilization (ISRU) to produce propellant for a future human mission, based on technology available within the next ten years. For this assessment, we performed a power-system design study for a scaled ISRU demonstrator lander on the Mars surface based on existing solar array technologies.

  9. Transmission grating Validation and Qualification for Mars and Future Planetary exploration Missions

    Science.gov (United States)

    Gallego, P.; Fernández, M.; Guembe, V.; Ramos, G.; González, C.; Prieto, J. A. R.; Canchal, R.; Moral, A.; Pérez, C.; Rull, F.

    2013-09-01

    In the frame of ExoMars 2018 mission (ESARoscosmos collaboration), the Instituto Nacional de Técnica Aeroespacial (INTA) in Spain, has successfully finish validation test plan of the transmission grating, one of the key optical components that forms part of the Spectrometer Unit of the instrument Raman Laser Spectrometrer that will be on board of ExoMars 2018 and that has never being qualified before.

  10. Cooperation and dialogical modeling for designing a safe Human space exploration mission to Mars

    Science.gov (United States)

    Grès, Stéphane; Tognini, Michel; Le Cardinal, Gilles; Zalila, Zyed; Gueydan, Guillaume

    2014-11-01

    This paper proposes an approach for a complex and innovative project requiring international contributions from different communities of knowledge and expertise. Designing a safe and reliable architecture for a manned mission to Mars or the Asteroids necessitates strong cooperation during the early stages of design to prevent and reduce risks for the astronauts at each step of the mission. The stake during design is to deal with the contradictions, antagonisms and paradoxes of the involved partners for the definition and modeling of a shared project of reference. As we see in our research which analyses the cognitive and social aspects of technological risks in major accidents, in such a project, the complexity of the global organization (during design and use) and the integration of a wide and varie d range of sciences and innovative technologies is likely to increase systemic risks as follows: human and cultural mistakes, potential defaults, failures and accidents. We identify as the main danger antiquated centralized models of organization and the operational limits of interdisciplinarity in the sciences. Beyond this, we can see that we need to take carefully into account human cooperation and the quality of relations between heterogeneous partners. Designing an open, self-learning and reliable exploration system able to self-adapt in dangerous and unforeseen situations implies a collective networked intelligence led by a safe process that organizes interaction between the actors and the aims of the project. Our work, supported by the CNES (French Space Agency), proposes an innovative approach to the coordination of a complex project.

  11. To Explore the Clinical Features of Twin Pregnancy%双胎妊娠的临床特点分析

    Institute of Scientific and Technical Information of China (English)

    马智慧

    2015-01-01

    ObjectiveTo investigate the clinical characteristics and treatment of twin pregnancy.MethodsThe twin pregnancy in the maternity department of our hospital were selected in this study. The clinical features, complications and treatment were analyzed in gestation period and the stage of labor.Results In the 30 patients of twin pregnancies, 10 cases received vaginal delivery, 20 cases received cesarean section, without the death of perinatal infants.Conclusion The incidence of complication for the twin pregnancy is high in gestation period and the stage of labor, with high incidence of premature delivery, low birth weight and children with birth defect which increase the perinatal mortality. So twin pregnancy is high-risk pregnancy.%目的:探讨双胎妊娠的临床特点与处理。方法选取我院的30例双胎妊娠产妇,对妊娠期与分娩期的临床特点、并发症及处理方法进行分析。结果双胎妊娠患者30例,阴道分娩10例,剖宫产20例,无围生儿死亡。结论双胎妊娠孕期及分娩期并发症多,早产率、低体重儿、畸形儿发生率高,使围产儿死亡率增加,为高危妊娠范畴。

  12. Mars Public Engagement Overview

    Science.gov (United States)

    Johnson, Christine

    2009-01-01

    This viewgraph presentation reviews the Mars public engagement goal to understand and protect our home planet, explore the Universe and search for life, and to inspire the next generation of explorers. Teacher workshops, robotics education, Mars student imaging and analysis programs, MARS Student Imaging Project (MSIP), Russian student participation, MARS museum visualization alliance, and commercialization concepts are all addressed in this project.

  13. The Proposed Mars Astrobiology Explorer - Cacher [MAX-C] Rover: First Step in a Potential Sample Return Campaign

    Science.gov (United States)

    Allen, Carlton C.; Beaty, David W.

    2010-01-01

    Sample return from Mars has been advocated by numerous scientific advisory panels for over 30 years, most prominently beginning with the National Research Council s [1] strategy for the exploration of the inner solar system, and most recently by the Mars Exploration Program Analysis Group (MEPAG s) Next Decade Science Analysis Group [2]. Analysis of samples here on Earth would have enormous advantages over in situ analyses in producing the data quality needed to address many of the complex scientific questions the community has posed about Mars. Instead of a small, predetermined set of analytical techniques, state of the art preparative and instrumental resources of the entire scientific community could be applied to the samples. The analytical emphasis could shift as the meaning of each result becomes better appreciated. These arguments apply both to igneous rocks and to layered sedimentary materials, either of which could contain water and other volatile constituents. In 2009 MEPAG formed the Mid-Range Rover Science Analysis Group (MRR-SAG) to formulate a mission concept that would address two general objectives: (1) conduct high-priority in situ science and (2) make concrete steps towards the potential return of samples to Earth. This analysis resulted in a mission concept named the Mars Astrobiology Explorer-Cacher (MAX-C), which was envisioned for launch in the 2018 opportunity. After extensive discussion, this group concluded that by far the most definitive contribution to sample return by this mission would be to collect and cache, in an accessible location, a suite of compelling samples that could potentially be recovered and returned by a subsequent mission. This would have the effect of separating two of the essential functions of MSR, the acquisition of the sample collection and its delivery to martian orbit, into two missions.

  14. A Low-Cost, Low-Risk Mission Concept for the Return of Martian Atmospheric Dust: Relevance to Human Exploration of Mars

    Science.gov (United States)

    Wadhwa, M.; Leshin, L.; Clark, B.; Jones, S.; Jurewicz, A.; McLennan, S.; Mischna, M.; Ruff, S.; Squyres, S.; Westphal, A.

    2017-06-01

    We present a low-cost, low-risk mission concept for return of martian atmospheric dust. Such a mission would serve as a scientific, technological and operational pathfinder for future surface sample return and human exploration to Mars.

  15. Mesoscale modeling of the water vapor cycle at Mawrth Vallis: a Mars2020 and ExoMars exploration rovers high-priority landing site

    Science.gov (United States)

    Pla-García, Jorge

    2017-04-01

    . During this transition, there is surface convergence into the rising branch (similar to the inter-tropical convergence zone on Earth), and dual Hadley cells with one circulation in each hemisphere. At this time, the mean surface winds flow from the high latitudes to equator in both hemispheres, providing the possibility for a direct vapor connection [5, 6]. It is likely that transient waves (e.g., storm systems) as well as boundary currents associated with planetary-scale stationary waves could advect and mix water equatorward, along the surface, in opposition to the Hadley Cell. Conclusion: We are studying whether moist air in northern spring/summer makes it to the surface of Mawrth at Ls 90, Ls 140 and Ls 180, three periods with high column abundance of water vapor at mid/high latitudes. The objective is to determine if the circulation (mean or regional) is favorable for the transport of water vapor from the north polar cap to MV where it might activate hygroscopic salts and/or chlorides [7]. Relative humidity at those different seasons is estimated to test for consistency with column abundances derived from orbit observations. If moist air makes it to MV during Ls90, 140 and/or 180, it should be a go-to site due to enhanced habitability implications. References: [1] Pla-García, J., & Rafkin, S. C., 2015: Meteorological predictions for Mars 2020 Exploration Rov-er high-priority landing sites throug MRAMS Mesoscale Modeling. In EGU General Assembly Conference Abstracts (Vol. 17, p. 12605). [2] Rafkin, S. C. R., Haberle, R. M., and T. I. Michaels, 2001: The Mars Regional Atmospheric Modeling System (MRAMS): Model description and selected simulations. Icarus, 151, 228-256. [3] Rafkin, S. C. R., M. R. V. Sta. Maria, and T. I. Michaels, 2002: Simulation of the atmospheric thermal circulation of a martian volcano using a mesoscale numerical model. Nature, 419, 697-699. [4] Jakosky, B.M., and C.B. Farmer, 1982: The seasonal and global behavior of water vapor in the Mars

  16. Exploring the Cloud Icy Early Mars Hypothesis Through Geochemistry and Mineralogy

    Science.gov (United States)

    Niles, P. B.; Michalski, J. R.

    2015-01-01

    While ancient fluvial channels have long been considered strong evidence for early surface water on Mars, many aspects of the fluvial morphology and occurrence suggest that they formed in relatively water limited conditions (com-pared to Earth) and that climatic excursions allowing for surface water might have been short-lived. Updated results mapping valley networks at higher resolution have changed this paradigm, showing that channels are much more abundant and wide-spread, and of higher order than was previously recognized, suggesting that Mars had a dense enough atmosphere and warm enough climate to allow channel formation up to 3.6-3.8 Ga. This revised view of the ancient martian climate might be broadly consistent with a climate history of Mars devised from infrared remote sensing of surface minerals, suggesting that widespread clay minerals formed in the Noachian, giving way to a sulfur-dominated surface weathering system by approx. 3.7 Ga.

  17. A High-Heritage Blunt-Body Entry, Descent, and Landing Concept for Human Mars Exploration

    Science.gov (United States)

    Price, Humphrey; Manning, Robert; Sklyanskiy, Evgeniy; Braun, Robert

    2016-01-01

    Human-scale landers require the delivery of much heavier payloads to the surface of Mars than is possible with entry, descent, and landing (EDL) approaches used to date. A conceptual design was developed for a 10 m diameter crewed Mars lander with an entry mass of approx.75 t that could deliver approx.28 t of useful landed mass (ULM) to a zero Mars areoid, or lower, elevation. The EDL design centers upon use of a high ballistic coefficient blunt-body entry vehicle and throttled supersonic retro-propulsion (SRP). The design concept includes a 26 t Mars Ascent Vehicle (MAV) that could support a crew of 2 for approx.24 days, a crew of 3 for approx.16 days, or a crew of 4 for approx.12 days. The MAV concept is for a fully-fueled single-stage vehicle that utilizes a single pump-fed 250 kN engine using Mono-Methyl Hydrazine (MMH) and Mixed Oxides of Nitrogen (MON-25) propellants that would deliver the crew to a low Mars orbit (LMO) at the end of the surface mission. The MAV concept could potentially provide abort-to-orbit capability during much of the EDL profile in response to fault conditions and could accommodate return to orbit for cases where the MAV had no access to other Mars surface infrastructure. The design concept for the descent stage utilizes six 250 kN MMH/MON-25 engines that would have very high commonality with the MAV engine. Analysis indicates that the MAV would require approx.20 t of propellant (including residuals) and the descent stage would require approx.21 t of propellant. The addition of a 12 m diameter supersonic inflatable aerodynamic decelerator (SIAD), based on a proven flight design, was studied as an optional method to improve the ULM fraction, reducing the required descent propellant by approx.4 t.

  18. Options for the human exploration of Mars using Solar Electric propulsion

    Science.gov (United States)

    Gefert, Leon P.; Hack, Kurt J.; Kerslake, Thomas W.

    1999-01-01

    Solar Electric propulsion (SEP) is examined as a candidate transportation option for human missions to Mars. Focus is given to an Earth-escape staging concept. This concept uses a SEP system to transfer from low earth orbit (LEO) to a high-energy elliptical parking orbit (HEEPO) and a chemical propulsion system to transfer from the HEEPO to a hyperbolic escape trajectory. LEO to Earth escape performance of these combined transportation systems is comparable to that of a nuclear thermal rocket (NTR). As a result, a mass efficient non-nuclear transportation architecture with fast, 180 day, Earth-to-Mars piloted transit times is enabled.

  19. Survival and sacrifice in Mars exploration what we know from polar expeditions

    CERN Document Server

    Seedhouse, Erik

    2015-01-01

    With current technology, a voyage to Mars and back will take three years. That’s a lot of time for things to go wrong. But sooner or later a commercial enterprise will commit itself to sending humans to Mars. How will the astronauts survive? Some things to consider are: ith current technology, a voyage to Mars and back will take three years. That’s a lot of time for things to go wrong. But sooner or later a commercial enterprise will commit itself to sending humans to Mars. How will the astronauts survive? Some things to consider are: • Who decides what medical resources are used for whom? Who decides what medical resources are used for whom? • What is the relative weight of mission success and the health of the crew? What is the relative weight of mission success and the health of the crew? • Do we allow crewmembers to sacrifi ce their lives for the good of the mission? Do we allow crewmembers to sacrifi ce their lives for the good of the mission? • And what if a crewmember does perish? Do we sto...

  20. A High Power Solar Electric Propulsion - Chemical Mission for Human Exploration of Mars

    Science.gov (United States)

    Burke, Laura M.; Martini, Michael C.; Oleson, Steven R.

    2014-01-01

    Recently Solar Electric Propulsion (SEP) as a main propulsion system has been investigated as an option to support manned space missions to near-Earth destinations for the NASA Gateway spacecraft. High efficiency SEP systems are able to reduce the amount of propellant long duration chemical missions require, ultimately reducing the required mass delivered to Low Earth Orbit (LEO) by a launch vehicle. However, for long duration interplanetary Mars missions, using SEP as the sole propulsion source alone may not be feasible due to the long trip times to reach and insert into the destination orbit. By combining an SEP propulsion system with a chemical propulsion system the mission is able to utilize the high-efficiency SEP for sustained vehicle acceleration and deceleration in heliocentric space and the chemical system for orbit insertion maneuvers and trans-earth injection, eliminating the need for long duration spirals. By capturing chemically instead of with low-thrust SEP, Mars stay time increases by nearly 200 days. Additionally, the size the of chemical propulsion system can be significantly reduced from that of a standard Mars mission because the SEP system greatly decreases the Mars arrival and departure hyperbolic excess velocities (V(sub infinity)).

  1. A Hands-on Exploration of the Retrograde Motion of Mars as Seen from the Earth

    Science.gov (United States)

    Pincelli, M. M.; Otranto, S.

    2013-01-01

    In this paper, we propose a set of activities based on the use of a celestial simulator to gain insights into the retrograde motion of Mars as seen from the Earth. These activities provide a useful link between the heliocentric concepts taught in schools and those tackled in typical introductory physics courses based on classical mechanics for…

  2. "Bimodal" Nuclear Thermal Rocket (BNTR) Propulsion for Future Human Mars Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.

    2004-01-01

    The Nuclear Thermal Rocket (NTR) Propulsion program is discussed. The Rover/NERVA program from 1959-1972 is compared with the current program. A key technology description, bimodal vehicle design for Mars Cargo and the crew transfer vehicle with inflatable module and artificial gravity capability, including diagrams are included. The LOX-Augmented NTR concept/operational features and characteristics are discussed.

  3. Orbital Synthetic Aperture Radar (SAR) for Mars Post Sample Return Exploration

    Science.gov (United States)

    Thompson, T. W.; Plaut, J. J.; Arvidson, R. E.; Paillou, P.

    2000-01-01

    A Mars orbital radar mission would use two frequencies to map the planet at 50 m resolution, penetrating 5-10 m. Some areas will be imaged at 5-m resolution. A 50-m resolution topographic map will be acquired, and surface changes detected.

  4. Mission from Mars - a method for exploring user requirements for children in a narrative space

    DEFF Research Database (Denmark)

    Dindler, Christian; Ludvigsen, Martin; Lykke-Olesen, Andreas

    2005-01-01

    In this paper a particular design method is propagated as a supplement to existing descriptive approaches to current practice studies especially suitable for gathering requirements for the design of children's technology. The Mission from Mars method was applied during the design of an electronic...

  5. Geographers of Mars: cartographic inscription and exploration narrative in late Victorian representations of the red planet.

    Science.gov (United States)

    Lane, K Maria D

    2005-12-01

    Over two decades spanning the turn of the twentieth century, astronomers' claims about the landscape and climate of Mars spurred widespread scientific and popular interest in the possibility that the red planet might be inhabited. This essay offers a new explanation for the power with which the notion of an inhabited Mars gripped noted scholars and everyday citizens on both sides of the Atlantic. Rather than pointing to a rekindling of age-old philosophical interest in the plurality of worlds, it argues that turn-of-the-century scientific narratives about Mars derived much of their power and popularity from ties with the newly established discipline of geography. From mapmaking to travelogue-style writing, astronomers borrowed powerful representational strategies from the discipline of geography to legitimize their claims about the red planet. In making the link between geographical and astronomical science more explicit, the essay further suggests that turn-of-the-century representations of Mars could be productively recontextualized alongside geographical works produced in the same period.

  6. The Mars Hopper: Development, Simulation and Experimental Validation of a Radioisotope Exploration Probe for the Martian Surface

    Energy Technology Data Exchange (ETDEWEB)

    Nathan D. Jerred; Spencer Cooley; Robert C. O' Brien; Steven D. Howe; James E. O' Brien

    2012-09-01

    An advanced exploration probe has been proposed by the Center for Space Nuclear Research (CSNR) to acquire detailed data from the Martian surface and subsurface, ‘hop’ large distances to multiple sites in short periods of time and perform this task repeatedly. Although several similar flying vehicles have been proposed utilizing various power sources and complex designs, e.g. solar-electric and chemical-based, the CSNR’s Mars Hopper is based on a radioisotope thermal rocket (RTR) concept. The Mars Hopper’s design relies on the high specific energies [J/kg] of radioisotopes and enhances their low specific power [W/kg] through the use of a thermal capacitance material to store thermal energy over time. During operation, the RTR transfers the stored thermal energy to a flowing gas, which is then expanded through a converging-diverging nozzle, producing thrust. Between flights, the platform will have ample time to perform in-depth science at each location while the propellant tanks and thermal capacitor recharge. Recharging the propellant tanks is accomplished by sublimation freezing of the ambient CO2 atmosphere with a cryocooler, followed by heating and pressurization to yield a liquid storage state. The proposed Mars Hopper will undergo a ballistic flight, consuming the propellant in both ascent and descent, and by using multiple hopper platforms, information can be gathered on a global scale, enabling better resource resolution and providing valuable information for a possible Mars sample-return mission. The CSNR, collaborating with the Idaho National Laboratory (INL) and three universities (University of Idaho, Utah State University and Oregon State University), has identified key components and sub-systems necessary for the proposed hopper. Current project activities include the development of a lab-scale prototypic Mars Hopper and test facility, along with computational fluid dynamics (CFD)/thermal-hydraulic models to yield a better understanding of the

  7. Exploration of paleoclimate and possible life on Mars%探索火星环境和生命

    Institute of Scientific and Technical Information of China (English)

    林杨挺

    2016-01-01

    火星最有可能孕育出地外生命,是人类未来实现太空移民的首选星球.水是生命不可或缺的要素之一,是寻找火星生命的关键线索;同时,水又是影响岩浆活动和构造运动的主要因素,是联系火星内部活动与表生环境演化的纽带.大量的火星探测结果揭示了火星古环境的演化历史,从约35亿年前曾存在河流湖泊演变为现代寒冷干燥的地表.火星陨石是目前唯一获得的火星岩石样品,既携带了火星岩浆活动的信息,又通过与水相互作用,记录了火星的环境演化.其中,中国的南极火星陨石提供了1.9亿年前火星存在地下水活动的证据,而另一个新降落的火星陨石保存了可能与生命活动相关的有机质.%Mars is the most promising planet where life may have emerged outside the Earth. It is the best candidate planet to immigrate in the future. Water is an essential constituent of life, which is the key clue of searching for life on Mars. Meanwhile, water plays an important role in magmatism and tectonic activity, connecting the interior processes and the climate evolution of Mars. Numerous Mars exploration missions have uncovered the paleoclimate history, evolving from the existence offluvial water ~3.5 billion years ago to the present cool and dry surface. Martian meteorites are the only available rock samples from Mars, carrying the information of the magmatism and the paleoclimate evolution via rock-water reaction on Mars. Evidence for the presence of groundwater on Mars ~190 million years ago was found in the Martian meteorite collected by the Chinese Antarctica Expedition, and possible life-related organic matter was discovered in the recent Tissint Martian meteorite fall.

  8. Mars Exploration Student Data Teams: Building Foundations and Influencing Students to Pursue STEM Careers through Experiences with Authentic Research

    Science.gov (United States)

    Turney, D.; Grigsby, B.; Murchie, S. L.; Buczkowski, D.; Seelos, K. D.; Nair, H.; McGovern, A.; Morgan, F.; Viviano, C. E.; Goudge, T. A.; Thompson, D.

    2013-12-01

    The Mars Exploration Student Data Teams (MESDT) immerses diverse teams of high school and undergraduate students in an authentic research Science, Technology, Engineering and Mathematics (STEM) based experience and allows students to be direct participants in the scientific process by working with scientists to analyze data sets from NASA's Mars program, specifically from the CRISM instrument. MESDT was created by Arizona State University's Mars Education Program, and is funded through NASA's Compact Reconnaissance Imaging Spectrometer for Mars or CRISM, an instrument onboard the Mars Reconnaissance Orbiter (MRO). Students work with teacher mentors and CRISM team members to analyze data, develop hypotheses, conduct research, submit proposals, critique and revise work. All students begin the program with basic Mars curriculum lessons developed by the MESDT education team. This foundation enables the program to be inclusive of all students. Teachers have reported that populations of students with diverse academic needs and abilities have been successful in this program. The use of technology in the classroom allows the MESDT program to successfully reach a nationwide audience and funding provided by NASA's CRISM instrument allows students to participate free of charge. Recent changes to the program incorporate a partnership with United States Geological Survey (USGS) and a CRISM sponsored competitive scholarship for two teams of students to present their work at the annual USGS Planetary Mappers Meeting. Returning MESDT teachers have attributed an increase in student enrollment and interest to this scholarship opportunity. The 2013 USGS Planetary Mappers Meeting was held in Washington DC which provided an opportunity for the students to meet with their Senators at the US Capitol to explain the science work they had done throughout the year as well as the impact that the program had had on their goals for the future. This opportunity extended to the students by the

  9. The Qingdao Twin Registry: a status update.

    Science.gov (United States)

    Duan, Haiping; Ning, Feng; Zhang, Dongfeng; Wang, Shaojie; Zhang, Dong; Tan, Qihua; Tian, Xiaocao; Pang, Zengchang

    2013-02-01

    In 1998, the Qingdao Twin Registry was initiated as the main part of the Chinese National Twin Registry. By 2005, a total of 10,655 twin pairs had been recruited. Since then new twin cohorts have been sampled, with one longitudinal cohort of adolescent twins selected to explore determinants of metabolic disorders and health behaviors during puberty and young adulthood. Adult twins have been sampled for studying heritability of multiple phenotypes associated with metabolic disorders. In addition, an elderly twin cohort has been recruited with a focus on genetic studies of aging-related phenotypes using twin modeling and genome-wide association analysis. Cross-cultural collaborative studies have been carried out between China, Denmark, Finland, and US cohorts. Ongoing data collection and analysis for the Qingdao Twin Registry will be discussed in this article.

  10. The Urey instrument: an advanced in situ organic and oxidant detector for Mars exploration.

    Science.gov (United States)

    Aubrey, Andrew D; Chalmers, John H; Bada, Jeffrey L; Grunthaner, Frank J; Amashukeli, Xenia; Willis, Peter; Skelley, Alison M; Mathies, Richard A; Quinn, Richard C; Zent, Aaron P; Ehrenfreund, Pascale; Amundson, Ron; Glavin, Daniel P; Botta, Oliver; Barron, Laurence; Blaney, Diana L; Clark, Benton C; Coleman, Max; Hofmann, Beda A; Josset, Jean-Luc; Rettberg, Petra; Ride, Sally; Robert, François; Sephton, Mark A; Yen, Albert

    2008-06-01

    The Urey organic and oxidant detector consists of a suite of instruments designed to search for several classes of organic molecules in the martian regolith and ascertain whether these compounds were produced by biotic or abiotic processes using chirality measurements. These experiments will also determine the chemical stability of organic molecules within the host regolith based on the presence and chemical reactivity of surface and atmospheric oxidants. Urey has been selected for the Pasteur payload on the European Space Agency's (ESA's) upcoming 2013 ExoMars rover mission. The diverse and effective capabilities of Urey make it an integral part of the payload and will help to achieve a large portion of the mission's primary scientific objective: "to search for signs of past and present life on Mars." This instrument is named in honor of Harold Urey for his seminal contributions to the fields of cosmochemistry and the origin of life.

  11. MOD: An Instrument for the 2005 Mars Explorer Program HEDS Payload

    Science.gov (United States)

    Bada, J. L.; Blaney, D. L.; Grunthaner, F. J.; McDonald, G. D.; Webster, C. R.; Duke, M.; Mathies, R. A.; McKay, C. P.; Paige, D. A.; Ride, S. K.

    2000-01-01

    The Mars Organic Detector (MOD) was recently selected for the definition phase of the HEDS '05 (originally scheduled for '03) lander instrument package for fundamental biology and in situ resource utilization. MOD is designed to detect organic compounds in rock and soil samples directly on the surface of Mars in order to assess the biological potential of the planet. In addition, a MOD Tunable Diode Laser Spectrometer (TDLS) will provide information on desorption and decomposition temperatures, as well as the release rates and quantities of water and carbon dioxide that can be liberated from regolith samples, thereby providing the parameters needed for the design of systems for the future large-scale in situ extraction of valuable consumable resources. A MOD TDLS will also measure the atmospheric water and carbon dioxide content, as well as the atmospheric carbon dioxide isotopic composition, in order to determine whether there is an isotopic offset between atmospheric and surface carbon.

  12. Consideration for solar system exploration - A system to Mars. [biomedical, environmental, and psychological factors

    Science.gov (United States)

    Nicogossian, Arnauld E.; Garshnek, Victoria

    1989-01-01

    Biomedical issues related to a manned mission to Mars are reviewed. Consideration is given to cardiovascular deconditioning, hematological and immunological changes, bone and muscle changes, nutritional issues, and the development of physiological countermeasures. Environmental issues are discussed, including radiation hazards, toxic chemical exposure, and the cabin environment. Also, human factors, performance and behavior, medical screening of the crew, disease prediction, and health maintenance are examined.

  13. Twin pregnancy

    DEFF Research Database (Denmark)

    Sperling, Lene; Tabor, A

    2001-01-01

    Determination of chorionicity is one of the most important issues in the management of twin pregnancy. Modern ultrasound equipment has made it possible to accurately assess placentation already in the first trimester with the lambda sign. With regard to prenatal diagnosis, it is important to know...... for clinicians caring for twin pregnancies....

  14. Modular Growth NTR Space Transportation System for Future NASA Human Lunar, NEA and Mars Exploration Missions

    Science.gov (United States)

    Borowski, Stanley K.; McCurdy, David R.; Packard, Thomas W.

    2012-01-01

    The nuclear thermal rocket (NTR) is a proven, high thrust propulsion technology that has twice the specific impulse (I(sub sp) approx.900 s) of today's best chemical rockets. During the Rover and NERVA (Nuclear Engine for Rocket Vehicle Applications) programs, twenty rocket reactors were designed, built and ground tested. These tests demonstrated: (1) a wide range of thrust; (2) high temperature carbide-based nuclear fuel; (3) sustained engine operation; (4) accumulated lifetime; and (5) restart capability - everything required for affordable human missions beyond LEO. In NASA's recent Mars Design Reference Architecture (DRA) 5.0 study, the NTR was selected as the preferred propulsion option because of its proven technology, higher performance, lower IMLEO, versatile vehicle design, and growth potential. Furthermore, the NTR requires no large technology scale-ups since the smallest engine tested during the Rover program - the 25 klb(sub f) "Pewee" engine is sufficient for human Mars missions when used in a clustered engine configuration. The "Copernicus" crewed Mars transfer vehicle developed for DRA 5.0 was an expendable design sized for fast-conjunction, long surface stay Mars missions. It therefore has significant propellant capacity allowing a reusable "1-year" round trip human mission to a large, high energy near Earth asteroid (NEA) like Apophis in 2028. Using a "split mission" approach, Copernicus and its two key elements - a common propulsion stage and integrated "saddle truss" and LH2 drop tank assembly - configured as an Earth Return Vehicle / propellant tanker, can also support a short round trip (approx.18 month) / short orbital stay (60 days) Mars reconnaissance mission in the early 2030's before a landing is attempted. The same short stay orbital mission can be performed with an "all-up" vehicle by adding an "in-line" LH2 tank to Copernicus to supply the extra propellant needed for this higher energy, opposition-class mission. To transition to a

  15. Integrating the Teaching of Space Science, Planetary Exploration And Robotics In Elementary And Middle School with Mars Rover Models

    Science.gov (United States)

    Bering, E. A.; Ramsey, J.; Smith, H.; Boyko, B. S.; Peck, S.; Arcenaux, W. H.

    2005-05-01

    The present aerospace engineering and science workforce is ageing. It is not clear that the US education system will produce enough qualified replacements to meet the need in the near future. Unfortunately, by the time many students get to high school, it is often too late to get them pointed toward an engineering or science career. Since some college programs require 6 units of high school mathematics for admission, students need to begin consciously preparing for a science or engineering curriculum as early as 6th or 7th grade. The challenge for educators is to convince elementary school students that science and engineering are both exciting, relevant and accessible career paths. This paper describes a program designed to help provide some excitement and relevance. It is based on the task of developing a mobile robot or "Rover" to explore the surface of Mars. There are two components to the program, a curriculum unit and a contest. The curriculum unit is structured as a 6-week planetary science unit for elementary school (grades 3-5). It can also be used as a curriculum unit, enrichment program or extracurricular activity in grades 6-8 by increasing the expected level of scientific sophistication in the mission design. The second component is a citywide competition to select the most outstanding models that is held annually at a local college or University. Primary (Grades 3-5) and middle school (Grades 6-8) students interested in science and engineering will design and build of a model of a Mars Rover to carry out a specific science mission on the surface of Mars. The students will build the models as part of a 6-week Fall semester classroom-learning or homework project on Mars. The students will be given design criteria for a rover, and be required to do basic research on Mars that will determine the operational objectives and structural features of their rover. This module may be used as part of a class studying general science, earth science, solar system

  16. Mars Rover Model Celebration: Using Planetary Exploration To Enrich STEM Teaching In Elementary And Middle School

    Science.gov (United States)

    Bering, E. A.; Ramsey, J.; Dominey, W.; Kapral, A.; Carlson, C.; Konstantinidis, I.; James, J.; Sweaney, S.; Mendez, R.

    2011-12-01

    The present aerospace engineering and science workforce is ageing. It is not clear that the US education system will produce enough qualified replacements to meet the need in the near future. Unfortunately, by the time many students get to high school, it is often too late to get them pointed toward an engineering or science career. Since some college programs require 6 units of high school mathematics for admission, students need to begin consciously preparing for a science or engineering curriculum as early as 6th or 7th grade. The challenge for educators is to convince elementary school students that science and engineering are both exciting, relevant and accessible career paths. The recent NASA Mars Rover missions capture the imagination of children, as NASA missions have done for decades. The University of Houston is in the process of developing a prototype of a flexible program that offers children an in-depth educational experience culminating in the design and construction of their own model rover. The existing prototype program is called the Mars Rover Model Celebration. It focuses on students, teachers and parents in grades 3-8. Students will design and build a model of a Mars rover to carry out a student selected science mission on the surface of Mars. The model will be a mock-up, constructed at a minimal cost from art supplies. The students will build the models as part of a project on Mars. The students will be given design criteria for a rover and will do basic research on Mars that will determine the objectives and features of their rover. This project may be used either informally as an after school club or youth group activity or formally as part of a class studying general science, earth science, solar system astronomy or robotics, or as a multi-disciplinary unit for a gifted and talented program. The program culminates in a capstone event held at the University of Houston (or other central location in the other communities that will be involved

  17. Mission from Mars - a method for exploring user requirements for children in a narrative space

    DEFF Research Database (Denmark)

    Dindler, Christian; Ludvigsen, Martin; Lykke-Olesen, Andreas;

    2005-01-01

    In this paper a particular design method is propagated as a supplement to existing descriptive approaches to current practice studies especially suitable for gathering requirements for the design of children's technology. The Mission from Mars method was applied during the design of an electronic...... school bag (eBag). The three-hour collaborative session provides a first-hand insight into children's practice in a fun and intriguing way. The method is proposed as a supplement to existing descriptive design methods for interaction design and children....

  18. Site Selection for Mars Surveyor Landing Sites: Some Key Factors for 2001 and Relation to Long-Term Exploration of Mars

    Science.gov (United States)

    Head, James W.

    1999-01-01

    The Site Selection Process: Site selection as a process can be subdivided into several main elements and these can be represented as the corners of a tetrahedron. Successful site selection outcome requires the interactions between these elements or corners, and should also take into account several other external factors or considerations. In principle, elements should be defined in approximately the following order: (1) major scientific and programmatic goals and objectives: What are the major questions that are being asked, goals that should be achieved, and objectives that must be accomplished. Do programmatic goals (e.g., sample return) differ from mission goals (e.g., precursor to sample return)? It is most helpful if these questions can be placed in the context of site characterization and hypothesis testing (e.g., Was Mars warm and wet in the Noachian? Land at a Noachian-aged site that shows evidence of surface water and characterize it specifically to address this question). Goals and objectives, then, help define important engineering factors such as type of payload, landing regions of interest (highlands, lowlands, smooth, rough, etc.), mobility, mission duration, etc. Goals and objectives then lead to: (2) spacecraft design and engineering landing site constraints: the spacecraft is designed to optimize the areas that will meet the goals and objectives, but this in turn introduces constraints that must be met in the selection of a landing site. Scientific and programmatic goals and objectives also help to define (3), the specific lander scientific payload requirements and capabilities. For example, what observations and experiments are required to address the major questions? How do we characterize the site in reference to the specific questions? Is mobility required and if so, how much? Which experiments are on the spacecraft, which on the rover? The results of these deliberations should lead to a surface exploration strategy, in which the goals and

  19. Noctis Landing: A Proposed Landing Site/Exploration Zone for Human Missions to the Surface of Mars

    Science.gov (United States)

    Lee, Pascal; Acedillo, Shannen; Braham, Stephen; Brown, Adrian; Elphic, Richard; Fong, Terry; Glass, Brian; Hoftun, Christopher; Johansen, Brage W.; Lorber, Kira; Mittlefehldt, David; Takagi, Yuta; Thomas, Peter; West, Michael; West, Stephen; Zolensky, Michael

    2015-01-01

    ) offer many such outcrop options. -­- Identifiable stratigraphic contacts and cross-cutting relationships from which relative ages can be determined. In place and collapsed canyon walls in NL, TC, and IC offer such opportunities. -­- Other types of ROIs include access points to surrounding plateau top areas for longer term regional exploration. A key attribute of the proposed Noctic Landing site is its strategic location to allow the shortest possible surface excusions to Tharsis and Valles Marineris (VM). VM is the feature and region on Mars that exposes the longest record of Mars' geology and evolution through time. Tharsis is the region of Mars that has experienced the longest and most extensive volcanic history, and might still be volcanically active. Some of the youngest lava flows on Mars have been identified on the western flanks of the Tharsis Bulge, i.e., within driving range of future longrange (500 - 1000 km) pressurized rover traverses. The proposed site also contains ROIs that offer the following Resources (incl. Civil Engineering) characteristics: -­- Access to raw material that exhibits the potential to (1) be used as feedstock for water-generating in situ resource utilization (ISRU) processes and (2) yield significant quantities (greater than 100 MT) of water. The raw material is likely in the form of hydrated minerals, and possibly ice/regolith mix. The top of the raw material deposit is at the surface. -­- Access to a region where infrastructure can be emplaced or constructed. This region is less than 5 km from the LS and contains flat, stable terrain. The region exhibits evidence for an abundant source of loose regolith. Several deep pits in the area combined with the availability of sand suggests that some natural terrain features can be adapted for construction purposes. -­- Access to raw material that exhibits the potential to be used as metal feedstock for ISRU and construction purposes. Iron and sulfur-rich mineral surface deposits have been

  20. Japan's Exploration of Holes and Caves on the Moon and Mars — UZUME Project

    Science.gov (United States)

    Haruyama, J.; Kawano, I.; Iwata, T.; Nishibori, T.; Yamamoto, Y.; Otsuki, M.; Shimada, K.; Sakurai, M.

    2015-10-01

    Many Japanese scientists and engineers are discussing an exploration program of the lunar and Martian holes and caverns. The name of the program is Unprecedented Zipangu Underworld of the Moon Exploration (UZUME; after a Japanese goddess).

  1. Human Factor Studies on a Mars Analogue During Crew 100b International Lunar Exploration Working Group EuroMoonMars Crew: Proposed New Approaches for Future Human Space and Interplanetary Missions.

    Science.gov (United States)

    Rai, Balwant; Kaur, Jasdeep

    2012-11-01

    Knowing the risks, costs, and complexities associated with human missions to Mars, analogue research can be a great (low-risk) tool for exploring the challenges associated with the preparation for living, operating, and undertaking research in interplanetary missions. Short-duration analogue studies, such as those being accomplished at the Mars Desert Research Station (MDRS), offer the chance to study mission operations and human factors in a simulated environment, and therefore contribute to exploration of the Moon and Mars in planned future missions. This article is based upon previously published articles, abstracts, and presentations by a series of independent authors, human factor studies performed on mars analogue station by Crew 100B. The MDRS Crew 100B performed studies over 15 days providing a unique insight into human factor issues in simulated short-duration Mars mission. In this study, 15 human factors were evaluated and analyzed by subjective and objective means, and from the summary of results it was concluded that optimum health of an individual and the crew as a whole is a necessity in order to encourage and maintain high performance and the satisfaction of project goals.

  2. Sedimentological evidence for a deltaic origin of the western fan deposit in Jezero crater, Mars and implications for future exploration

    Science.gov (United States)

    Goudge, Timothy A.; Milliken, Ralph E.; Head, James W.; Mustard, John F.; Fassett, Caleb I.

    2017-01-01

    We examine the stratigraphic architecture and mineralogy of the western fan deposit in the Jezero crater paleolake on Mars to reassess whether this fan formed as a delta in a standing body of water, as opposed to by alluvial or debris flow processes. Analysis of topography and images reveals that the stratigraphically lowest layers within the fan have shallow dips (<2°), consistent with deltaic bottomsets, whereas overlying strata exhibit steeper dips (∼2-9°) and downlap, consistent with delta foresets. Strong clay mineral signatures (Fe/Mg-smectite) are identified in the inferred bottomsets, as would be expected in the distal fine-grained facies of a delta. We conclude that the Jezero crater western fan deposit is deltaic in origin based on the exposed stratal geometries and mineralogy, and we emphasize the importance of examining the stratigraphic architecture of sedimentary fan deposits on Mars to confidently distinguish between alluvial fans and deltas. Our results indicate that Jezero crater contains exceptionally well-preserved fluvio-deltaic stratigraphy, including strata interpreted as fine-grained deltaic bottomsets that would have had a high potential to concentrate and preserve organic matter. Future exploration of this site is both geologically and astrobiologically compelling, and in situ analyses would be complementary to the ongoing in situ characterization of fluvio-lacustrine sediment in the Gale crater paleolake basin by the Curiosity rover.

  3. Zapping rocks on Mars: exploring the Red Planet with Curiosity and its laser (Presentation Video)

    Science.gov (United States)

    Wiens, Roger C.

    2013-09-01

    When the one-ton Curiosity Rover landed on Mars in 2012, one of the ten instruments was a joint French and US-built laser remote sensing device. ChemCam ablates small amounts of rock and soil up to 25 feet away to determine their compositions by observing the plasma emission from a minute 0.5 mm analysis footprint. This "LIBS" technique provides semi-quantitative compositions with sensitivity to nearly every element in the periodic table, and with the important abilities to blast dust away prior to a rock analysis and to perform depth profiles with successive shots in one spot. Over 40,000 spectra have been returned in the first seven months of the mission. The talk will describe ChemCam and give an overview of the initial part of Curiosity's mission.

  4. Astrobiology Exploration Strategies for the Mars Polar Regions Using Balloon Platforms

    Science.gov (United States)

    Mahaffy, P. R.; Atreya, S. A.; Fairbrother, D. A.; Farrell, W. M.; Gorevan, S.; Jones, J.; Mitrofanov, I.; Scott, J.

    2003-01-01

    Montgolfiere balloons can provide a unique near-surface platform for an extended traverse over the polar regions of Mars. During the polar summer, such solar powered balloons would remain in the constant sun of the polar summer and could remain airborne for many weeks or even months as the atmospheric circulation would drive the balloons around the polar region many times before the balloon would cross the terminator. Such a platform for scientific measurements could provide in situ sampling of the atmosphere for trace disequilibrium species that might be indicators of present geological or biological activity in this regon. It could furthermore provide high resolution imaging, deep electromagnetic (EM) sounding for subsurface stratigraphy and liquid water, and high spatial resolution neutron measurements of subsurface ice. Technologies for robust balloon deployment on entry and controlled encounters with the surface and near subsurface for sample acquisition in otherwise inaccessible regions are presently being studied and developed with support from NASA.

  5. To Mars and beyond, fast! how plasma propulsion will revolutionize space exploration

    CERN Document Server

    Chang Díaz, Franklin

    2017-01-01

    As advanced space propulsion moves slowly from science fiction to achievable reality, the Variable Specific Impulse Magnetoplasma Rocket, or VASIMR, is a leading contender for making 'Mars in a month' a possibility. Developed by Ad Astra Rockets, which was founded by astronaut Franklin Chang-Diaz and backed by NASA, its first commercial tests are imminent. VASIMR heats plasma to extreme temperatures using radio waves. Strong magnetic fields then funnel this plasma out the back of the engine, creating thrust. The continuous propulsion may place long, fast interplanetary journeys within reach in the near future. While scientists dream of the possibilities of using fusion or well-controlled matter-antimatter interactions to propel spacecraft fast and far, that goal is still some way over the horizon. VASIMR provides a more attainable propulsion technology that is based on the matter-antimatter concept. The book describes a landmark technology grounded in plasma physics and offering a practical technological solu...

  6. Moon and Mars Caves: New Paradigm for Human Exploration and Precursor Steps

    Science.gov (United States)

    Blamont, Jacques

    2016-07-01

    Habitat on lava tubes, recently discovered on the Moon and Mars, offer protection against planetary hazards and should become a unifying concept for the preparation and the deployment of occupancy, first on the Moon, then on Mars, around which a phased plan could be established and pursued. A road map has to be worked out. Two types of research programs should be implemented: - Search for lava tubes by dedicated orbiters - Development of specific technology (heavy machinery, inflatable structures for housing, etc.) These programs would be incorporated first in the Robotic Village, then in an International Lunar Base. The first step has to be to obtain a complete map of the lunar surface at the resolution of 25 cm, which would certainly discover, display and characterize many pits, skylights and tube features. Main emphasis would be placed on Polar Regions. The data would be collected by nanosats placed on low lunar orbits (altitude 50 km). Each of them will carry a 15 cm diameter telescope and a 1000x1000 pixels detector providing a 25 cm resolution over a field 250 mx250m wide. Similar to the satellites of Planet Labs, they could fit on an existing microbus designed by OHB. The mapping can be accomplished by 8 satellites, each which a lifetime in orbit of 6 months. The nanosats would be placed on Lunar orbit by a spacecraft launched as a piggyback, either on a commercial or on a dedicated mission to GTO, why not the first launch of Ariane 6 ! They would be transferred from GTO to the Moon by electric propulsion A data relay at the Earth-Moon L-2 position may be necessary.

  7. Mars Gashopper Airplane Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Mars Gas Hopper Airplane, or "gashopper" is a novel concept for propulsion of a robust Mars flight and surface exploration vehicle that utilizes indigenous CO2...

  8. Relays from Mars demonstrate international interplanetary networking

    Science.gov (United States)

    2004-08-01

    .” In addition, Mars Express is verifying two other operating modes with Opportunity and the twin rover, Spirit, from a greater distance. On 3 and 6 August, when Mars Express listened to Spirit, it was about 6000 kilometres above the surface. At this range it successfully tracked a beacon from Spirit, demonstrating a capability that can be used to locate another craft during critical events, such as the descent to a planet’s surface, or for orbital rendez-vous manoeuvres. “Establishing a reliable communication network around Mars or other planets is crucial for future exploration missions, as it will allow improved coverage and also an increase in the amount of data that can be brought back to Earth,” said Con McCarthy, from ESA’s Mars Express project, “the tracking mode will enable ESA and NASA to pinpoint a spacecraft’s position more accurately during critical mission phases.” The final session of the series, scheduled for 13 August with Opportunity, will demonstrate a mode for gaining navigational information from the ‘Doppler shift’ in the radio signal.

  9. The Mars Astrobiology Explorer-Cacher (MAX-C): a potential rover mission for 2018. Final report of the Mars Mid-Range Rover Science Analysis Group (MRR-SAG) October 14, 2009.

    Science.gov (United States)

    2010-03-01

    This report documents the work of the Mid-Range Rover Science Analysis Group (MRR-SAG), which was assigned to formulate a concept for a potential rover mission that could be launched to Mars in 2018. Based on programmatic and engineering considerations as of April 2009, our deliberations assumed that the potential mission would use the Mars Science Laboratory (MSL) sky-crane landing system and include a single solar-powered rover. The mission would also have a targeting accuracy of approximately 7 km (semimajor axis landing ellipse), a mobility range of at least 10 km, and a lifetime on the martian surface of at least 1 Earth year. An additional key consideration, given recently declining budgets and cost growth issues with MSL, is that the proposed rover must have lower cost and cost risk than those of MSL--this is an essential consideration for the Mars Exploration Program Analysis Group (MEPAG). The MRR-SAG was asked to formulate a mission concept that would address two general objectives: (1) conduct high priority in situ science and (2) make concrete steps toward the potential return of samples to Earth. The proposed means of achieving these two goals while balancing the trade-offs between them are described here in detail. We propose the name Mars Astrobiology Explorer-Cacher(MAX-C) to reflect the dual purpose of this potential 2018 rover mission.

  10. Twin Baryogenesis

    CERN Document Server

    Farina, Marco; Shin, Chang Sub

    2016-01-01

    In the context of Twin Higgs models, we study a simple mechanism that simultaneously generates asymmetries in the dark and visible sector through the out-of-equilibrium decay of a TeV scale particle charged under a combination of baryon and twin baryon number. We predict the dark matter to be a 5 GeV twin baryon, which is easy to achieve because of the similarity between the two confinement scales. Dark matter is metastable and can decay to three quarks, yielding indirect detection signatures. The mechanism requires the introduction of a new colored particle, typically within the reach of the LHC, of which we study the rich collider phenomenology, including prompt and displaced dijets, multi-jets, monojets and monotops.

  11. Exploring the Relation between Prenatal and Neonatal Complications and Later Autistic-Like Features in a Representative Community Sample of Twins

    Science.gov (United States)

    Ronald, Angelica; Happe, Francesca; Dworzynski, Katharina; Bolton, Patrick; Plomin, Robert

    2010-01-01

    Prenatal and neonatal events were reported by parents of 13,690 eighteen-month-old twins enrolled in the Twins Early Development Study, a representative community sample born in England and Wales. At ages 7-8, parents and teachers completed questionnaires on social and nonsocial autistic-like features and parents completed the Childhood Asperger…

  12. Physical properties of the Mars Exploration Rover landing sites as inferred from Mini-TES-derived thermal inertia

    Science.gov (United States)

    Fergason, R.L.; Christensen, P.R.; Bell, J.F.; Golombek, M.P.; Herkenhoff, K. E.; Kieffer, H.H.

    2006-01-01

    The Miniature Thermal Emission Spectrometer (Mini-TES) on board the two Mars Exploration Rovers provides the first opportunity to observe thermal properties from the Martian surface, relate these properties to orbital data, and perform soil conductivity experiments under Martian conditions. The thermal inertias of soils, bedforms, and rock at each landing site were derived to quantify the physical properties of these features and understand geologic processes occurring at these localities. The thermal inertia for the. Gusev plains rock target Bonneville Beacon (???1200 J m-2 K-1 s-1/2) is consistent with a dense, basaltic rock, but the rocks at the Columbia Hills have a lower thermal inertia (???620 J m-2 K-1 s-1/2), suggesting that they have a volcaniclasic origin. Bedforms on the floors of craters at both landing sites have thermal inertias of 200 J m-2 K-1 s-1/2, consistent with a particle diameter of ???160 ??m. This diameter is comparable to the most easily moved grain size in the current atmosphere on Mars, suggesting that these bedforms may have formed under current atmospheric conditions. Along the Meridiani plains, the thermal inertia is lower than that derived from TES and Thermal Emission Imaging System (THEMIS) orbital data. This discrepancy is not well understood. Mini-TES-derived thermal inertias at Gusev along a ???2.5 km traverse follow trends in thermal inertia measured from orbit with TES and THEMIS. However, along the traverse, there are variability and mixing of particle sizes that are not resolved in the orbital thermal inertia data due to meter-scale processes that are not identifiable at larger scales. Copyright 2006 by the American Geophysical Union.

  13. Precision ADCS of a spinning spacecraft for the Mars Aeronomy Explorer Mission

    Science.gov (United States)

    Mungas, Greg S.; Shotwell, Robert; Gray, Andrew

    2005-01-01

    This paper discusses a precision attitude and control technique for meeting these requirements utilizing a similar architecture that was adopted for the Laboratory of Atmospheric and Space Physics (LASP) SNOE (Student Nitrous Oxide Explorer) spinning spacecraft; SNOE has been operating with its ADCS architecture in low earth orbit (LEO) for over two years.

  14. Coupling Immersive Experiences with the Use of Mission Data to Encourage Students' Interest in Science, Technology, Engineering, and Math: Examples from the Mars Exploration Program

    Science.gov (United States)

    Klug, S. L.; Valderrama, P.; Viotti, M. A.; Watt, K.; Wurman, G.

    2004-12-01

    The Mars Exploration Program, in partnership with the Arizona State University Mars Education Program has created and successfully tested innovative pathways and programs that introduce, develop, and reinforce science, technology, engineering, and mathematics - STEM subjects into pre-college curriculum. With launches scheduled every 26 months, Mars has the unique opportunity and ability to have a long-term, systemic influence on science education. Also, because of the high level of interest in Mars, as exemplified by the10 billion Internet hits during the Mars Exploration Rover mission, it is a great vehicle for the infusion of current science into today's classrooms. These Mars education programs have linked current mission science and engineering with the National Education Standards, integrating them in a teacher-friendly and student-friendly format. These linkages are especially synergistic when combined with long-term partnerships between educators, Mars scientists and engineers, as they exemplify real-world collaborations and teamwork. To accommodate many different audience needs, an array of programs and a variety of approaches to these programs have been developed. High tech, low tech and no tech options can be implemented to help insure that as many students can be accommodated and impacted by these programs as possible. These programs are scaled to match the National Education Standards in the grade levels in which students need to become proficient in these subjects. The Mars Student Imaging Project - MSIP allows teams of students from the fifth grade through community college to be immersed in a hands-on program and experience the scientific process firsthand by using the Thermal Emission Imaging System - THEMIS camera to target their own image of Mars using an educational version of the real flight software used to target THEMIS images. The student teams then analyze their image and report their findings to the MSIP website. This project has been in

  15. Project Ares: A Systems Engineering and Operations Architecture for the Exploration of Mars

    Science.gov (United States)

    1992-03-20

    spherical reception pattern (8:3-47). This pattern will be important in the event the satellite begins to tumble and ground controllers are attempting...via these antennas, while limited telemetry and data will be transmitted via the Ka-band antennia as mentioned above. If the mapper begins tumbling ...Aeronautics and Astronautics, 24-26 June 1991. 32. Dryer , Murray. "Solar Wind Disturbances Caused by Planets and Solar Flares." Exploration of the Outer Solar

  16. GNC of the SphereX Robot for Extreme Environment Exploration on Mars

    OpenAIRE

    Kalita, Himangshu; Nallapu, Ravi teja; Warren, Andrew; Thangavelautham, Jekan

    2017-01-01

    Wheeled ground robots are limited from exploring extreme environments such as caves, lava tubes and skylights. Small robots that can utilize unconventional mobility through hopping, flying or rolling can overcome these limitations. Mul-tiple robots operating as a team offer significant benefits over a single large ro-bot, as they are not prone to single-point failure, enable distributed command and control and enable execution of tasks in parallel. These robots can complement large rovers and...

  17. A Subjective Assessment of Alternative Mission Architecture Operations Concepts for the Human Exploration of Mars at NASA Using a Three-Dimensional Multi-Criteria Decision Making Model

    Science.gov (United States)

    Tavana, Madjid

    2003-01-01

    The primary driver for developing missions to send humans to other planets is to generate significant scientific return. NASA plans human planetary explorations with an acceptable level of risk consistent with other manned operations. Space exploration risks can not be completely eliminated. Therefore, an acceptable level of cost, technical, safety, schedule, and political risks and benefits must be established for exploratory missions. This study uses a three-dimensional multi-criteria decision making model to identify the risks and benefits associated with three alternative mission architecture operations concepts for the human exploration of Mars identified by the Mission Operations Directorate at Johnson Space Center. The three alternatives considered in this study include split, combo lander, and dual scenarios. The model considers the seven phases of the mission including: 1) Earth Vicinity/Departure; 2) Mars Transfer; 3) Mars Arrival; 4) Planetary Surface; 5) Mars Vicinity/Departure; 6) Earth Transfer; and 7) Earth Arrival. Analytic Hierarchy Process (AHP) and subjective probability estimation are used to captures the experts belief concerning the risks and benefits of the three alternative scenarios through a series of sequential, rational, and analytical processes.

  18. Field reconnaissance geologic mapping of the Columbia Hills, Mars, based on Mars Exploration Rover Spirit and MRO HiRISE observations

    Science.gov (United States)

    Crumpler, L.S.; Arvidson, R. E.; Squyres, S. W.; McCoy, T.; Yingst, A.; Ruff, S.; Farrand, W.; McSween, Y.; Powell, M.; Ming, D. W.; Morris, R.V.; Bell, J.F.; Grant, J.; Greeley, R.; DesMarais, D.; Schmidt, M.; Cabrol, N.A.; Haldemann, A.; Lewis, K.W.; Wang, A.E.; Schroder, C.; Blaney, D.; Cohen, B.; Yen, A.; Farmer, J.; Gellert, Ralf; Guinness, E.A.; Herkenhoff, K. E.; Johnson, J. R.; Klingelhfer, G.; McEwen, A.; Rice, J.W.; Rice, M.; deSouza, P.; Hurowitz, J.

    2011-01-01

    Chemical, mineralogic, and lithologic ground truth was acquired for the first time on Mars in terrain units mapped using orbital Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment (MRO HiRISE) image data. Examination of several dozen outcrops shows that Mars is geologically complex at meter length scales, the record of its geologic history is well exposed, stratigraphic units may be identified and correlated across significant areas on the ground, and outcrops and geologic relationships between materials may be analyzed with techniques commonly employed in terrestrial field geology. Despite their burial during the course of Martian geologic time by widespread epiclastic materials, mobile fines, and fall deposits, the selective exhumation of deep and well-preserved geologic units has exposed undisturbed outcrops, stratigraphic sections, and structural information much as they are preserved and exposed on Earth. A rich geologic record awaits skilled future field investigators on Mars. The correlation of ground observations and orbital images enables construction of a corresponding geologic reconnaissance map. Most of the outcrops visited are interpreted to be pyroclastic, impactite, and epiclastic deposits overlying an unexposed substrate, probably related to a modified Gusev crater central peak. Fluids have altered chemistry and mineralogy of these protoliths in degrees that vary substantially within the same map unit. Examination of the rocks exposed above and below the major unconformity between the plains lavas and the Columbia Hills directly confirms the general conclusion from remote sensing in previous studies over past years that the early history of Mars was a time of more intense deposition and modification of the surface. Although the availability of fluids and the chemical and mineral activity declined from this early period, significant later volcanism and fluid convection enabled additional, if localized, chemical activity

  19. Task-Specific Ionic Liquids for Mars Exploration (Green Chemistry for a Red Planet)

    Science.gov (United States)

    Karr, L. J.; Curreri, P. A.; Paley, M. S.; Kaukler, W. F.; Marone, M. J.

    2012-01-01

    Ionic Liquids (ILs) are organic salts with low melting points that are liquid at or near room temperature. The combinations of available ions and task-specific molecular designability make them suitable for a huge variety of tasks. Because of their low flammability, low vapor pressure, and stability in harsh environments (extreme temperatures, hard vacuum) they are generally much safer and "greener" than conventional chemicals and are thus suitable for a wide range of applications that support NASA exploration goals. This presentation describes several of the ongoing applications that are being developed at MSFC.

  20. Issues of exploration: human health and wellbeing during a mission to Mars

    Science.gov (United States)

    White, R. J.; Bassingthwaighte, J. B.; Charles, J. B.; Kushmerick, M. J.; Newman, D. J.

    2003-01-01

    Today, the tools are in our hands to enable us to travel away from our home planet and become citizens of the solar system. Even now, we are seriously beginning to develop the robust infrastructure that will make the 21st century the Century of Space Travel. But this bold step must be taken with due concern for the health, safety and wellbeing of future space explorers. Our long experience with space biomedical research convinces us that, if we are to deal effectively with the medical and biomedical issues of exploration, then dramatic and bold steps are also necessary in this field. We can no longer treat the human body as if it were composed of muscles, bones, heart and brain acting independently. Instead, we must lead the effort to develop a fully integrated view of the body, with all parts connected and fully interacting in a realistic way. This paper will present the status of current (2000) plans by the National Space Biomedical Research Institute to initiate research in this area of integrative physiology and medicine. Specifically, three example projects are discussed as potential stepping stones towards the ultimate goal of producing a digital human. These projects relate to developing a functional model of the human musculoskeletal system and the heart. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  1. Rapid Biochemical Analysis on the International Space Station (ISS): Preparing for Human Exploration of the Moon and Mars

    Science.gov (United States)

    Maule, J.; Morris, Heather; Monaco, L.; Steele, A.; Wainwright, N.

    2008-01-01

    . The goals of this initial study were to i) test the cleanliness of reagents/supplies on orbit, ii) test the crew's ability to collect and process a sample in microgravity without contamination, iii) demonstrate nominal function of the LOCAD-PTS, and iv) provide a general survey of endotoxin within the ISS. The surface sites varied greatly in terms of their frequency-of-use and material texture/composition; from relatively smooth aluminum, to fabric, to the room temperature vulcanizing (RTV) rubber of a Extravehicular Mobility Unit (EMU) spacesuit. Results showed that: i) the swabbing kits and reagents remained clean on orbit, ii) the crew could collect and process a sample without contamination, and iii) the LOCAD-PTS functioned nominally in > 99% of the 55 tests completed. We will present detailed results of the survey of endotoxin on ISS surfaces. These results and technology are important in the near-term - by providing an extra tool in the toolbox for ISS microbial monitoring. They are also important in the longer term as valuable preparation for human exploration of the Moon and Mars. One of the proposed science goals for the human exploration of Mars will be to detect and characterize any indigenous biological molecules that may exist on the Martian surface. To achieve that goal, the crew must have the technology available onboard to differentiate indigenous biology from any terrestrial biological material brought to Mars by the spacecraft and crew (termed 'forward contamination'). The LAL assay is already one of the official methods used by NASA's planetary protection program to certify cleanliness of interplanetary robotic spacecraft prior to launch; and therefore endotoxin is a good marker of forward contamination (as well as other microbial molecules detectable with LOCAD-PTS e.g. box-1, 3-glucan and lipoteichoic acid). Furthermore, the distribution and abundance of these molecules on the ISS provides a good indicator of what to expect on the Crew

  2. Rapid Biochemical Analysis on the International Space Station (ISS): Preparing for Human Exploration of the Moon and Mars

    Science.gov (United States)

    Maule, J.; Morris, Heather; Monaco, L.; Steele, A.; Wainwright, N.

    2008-01-01

    . The goals of this initial study were to i) test the cleanliness of reagents/supplies on orbit, ii) test the crew's ability to collect and process a sample in microgravity without contamination, iii) demonstrate nominal function of the LOCAD-PTS, and iv) provide a general survey of endotoxin within the ISS. The surface sites varied greatly in terms of their frequency-of-use and material texture/composition; from relatively smooth aluminum, to fabric, to the room temperature vulcanizing (RTV) rubber of a Extravehicular Mobility Unit (EMU) spacesuit. Results showed that: i) the swabbing kits and reagents remained clean on orbit, ii) the crew could collect and process a sample without contamination, and iii) the LOCAD-PTS functioned nominally in > 99% of the 55 tests completed. We will present detailed results of the survey of endotoxin on ISS surfaces. These results and technology are important in the near-term - by providing an extra tool in the toolbox for ISS microbial monitoring. They are also important in the longer term as valuable preparation for human exploration of the Moon and Mars. One of the proposed science goals for the human exploration of Mars will be to detect and characterize any indigenous biological molecules that may exist on the Martian surface. To achieve that goal, the crew must have the technology available onboard to differentiate indigenous biology from any terrestrial biological material brought to Mars by the spacecraft and crew (termed 'forward contamination'). The LAL assay is already one of the official methods used by NASA's planetary protection program to certify cleanliness of interplanetary robotic spacecraft prior to launch; and therefore endotoxin is a good marker of forward contamination (as well as other microbial molecules detectable with LOCAD-PTS e.g. box-1, 3-glucan and lipoteichoic acid). Furthermore, the distribution and abundance of these molecules on the ISS provides a good indicator of what to expect on the Crew

  3. Twin vaginal delivery: innovate or abdicate.

    Science.gov (United States)

    Easter, Sarah Rae; Taouk, Laura; Schulkin, Jay; Robinson, Julian N

    2017-02-07

    Neonatal safety data along with national guidelines have prompted renewed interest in vaginal delivery of twins, particularly in the case of the noncephalic second twin. Yet, the rising rate of twin cesarean deliveries, coupled with the national decline in operative obstetrics, raises concerns about the availability of providers who are skilled in twin vaginal birth. Providers are key stakeholders for increasing rates of twin vaginal delivery. We surveyed a group of practicing obstetricians to explore potential barriers to the vaginal birth of twins with a focus on delivery of the noncephalic second twin. Among 107 responding providers, only 57% would deliver a noncephalic second twin by breech extraction. Providers who preferred breech extraction had a higher rate of maternal-fetal medicine subspecialty training (26.2% vs 4.3%; P30 sets of twins annually (57.4% vs 34.8%; P=.02). Most providers (54.2%) were familiar with the findings from the recent randomized trial that demonstrated the safety of twin vaginal birth. However, knowledge of the trial was not associated statistically with a preference for breech extraction (62.3% vs 43.5%; P=.05). Providers who preferred breech extraction were more likely to agree with recent society guidelines that encourage the vaginal birth of twins (86.9% vs 63.0%; Pinnovation. Without novel provider-focused strategies, we may relinquish passively the requisite skills for not only our patients but also for future generations of obstetricians.

  4. Fetal growth disorders in twin gestations.

    LENUS (Irish Health Repository)

    Breathnach, Fionnuala M

    2012-06-01

    Twin growth is frequently mismatched. This review serves to explore the pathophysiologic mechanisms that underlie growth aberrations in twin gestations, the prenatal recognition of abnormal twin growth, and the critical importance of stratifying management of abnormal twin growth by chorionicity. Although poor in utero growth of both twins may reflect maternal factors resulting in global uteroplacental dysfunction, discordant twin growth may be attributed to differences in genetic potential between co-twins, placental dysfunction confined to one placenta only, or one placental territory within a shared placenta. In addition, twin-twin transfusion syndrome represents a distinct entity of which discordant growth is a common feature. Discordant growth is recognized as an independent risk factor for adverse perinatal outcome. Intertwin birth weight disparity of 18% or more should be considered to represent a discordance threshold, which serves as an independent risk factor for adverse perinatal outcome. At this cutoff, perinatal morbidity is found to increase both for the larger and the smaller twin within a discordant pair. There remains uncertainty surrounding the sonographic parameters that are most predictive of discordance. Although heightening of fetal surveillance in the face of discordant twin growth follows the principles applied to singleton gestations complicated by fetal growth restriction, the timing of intervention is largely influenced by chorionicity.

  5. Deep Basalt Aquifers in Orcus Patera, Elysium Basin Mars: Perspectives for Exobiology Exploration

    Science.gov (United States)

    Grin, E. A.; Cabrol, N. A.

    1998-01-01

    simultaneously. Comparatively to terrestrial melts, Martian iron-rich melts are denser. This greater density implies greater effusion rates (eight-times terrestrial values), and larger fissuration widths (two-times terrestrial ones). With increasing vesiculation of magma, the bubbles interact with one-another because there are of similar pressure. They make a magma froth at the contact with the caldera surface, and on the walls of the fractures. In the saturated magma, froth, where the volume ratio of gases-to-liquid is about 4:1, the bubbles form a huge surface area of interconnected spaces. Bubbles near the caldera surface disrupt the magma, and fragmentation takes place, which moves downward through the magma column. On Earth, the bubbles are likely to grow between 1 and 50 mm in diameter due to the difference between the magma surface tension, and the bubble supersaturation pressure. The Martian low-pressure at surface level is likely to accelerate the expansion of the bubbles, and increase their final diameter and number, creating more voids in the magma. The strong magma froth with enclosed juvenile water bubbles interconnected with exsolved gas bubbles constitute a potential geothermal environment for geochemical energy production from basalt and water that does not require excessive temperatures. This process can start at +20C. Similar types of environments have been shown on Earth as potential energy sources for microbial metabolism, and could have provided deep aqueous basaltic niches for possible Martian microorganisms, even geologically recently. During the Amazonian, combination of volcanism and water activity still existed on Mars. Moreover, this type of potential niches open ways for investigation of possible oases of extinct or extant life, not only on paleolakes, and surface hydrothermalism spring areas, but also all large systems of fossae, which combine hydrologic and volcanic activities, and which provide an energy source, and an underground shelter to

  6. Deep Basalt Aquifers in Orcus Patera, Elysium Basin Mars: Perspectives for Exobiology Exploration

    Science.gov (United States)

    Grin, E. A.; Cabrol, N. A.

    1998-01-01

    simultaneously. Comparatively to terrestrial melts, Martian iron-rich melts are denser. This greater density implies greater effusion rates (eight-times terrestrial values), and larger fissuration widths (two-times terrestrial ones). With increasing vesiculation of magma, the bubbles interact with one-another because there are of similar pressure. They make a magma froth at the contact with the caldera surface, and on the walls of the fractures. In the saturated magma, froth, where the volume ratio of gases-to-liquid is about 4:1, the bubbles form a huge surface area of interconnected spaces. Bubbles near the caldera surface disrupt the magma, and fragmentation takes place, which moves downward through the magma column. On Earth, the bubbles are likely to grow between 1 and 50 mm in diameter due to the difference between the magma surface tension, and the bubble supersaturation pressure. The Martian low-pressure at surface level is likely to accelerate the expansion of the bubbles, and increase their final diameter and number, creating more voids in the magma. The strong magma froth with enclosed juvenile water bubbles interconnected with exsolved gas bubbles constitute a potential geothermal environment for geochemical energy production from basalt and water that does not require excessive temperatures. This process can start at +20C. Similar types of environments have been shown on Earth as potential energy sources for microbial metabolism, and could have provided deep aqueous basaltic niches for possible Martian microorganisms, even geologically recently. During the Amazonian, combination of volcanism and water activity still existed on Mars. Moreover, this type of potential niches open ways for investigation of possible oases of extinct or extant life, not only on paleolakes, and surface hydrothermalism spring areas, but also all large systems of fossae, which combine hydrologic and volcanic activities, and which provide an energy source, and an underground shelter to

  7. Robotic exploration of the solar system

    CERN Document Server

    Ulivi, Paolo

    In Robotic Exploration of the Solar System, Paolo Ulivi and David Harland provide a comprehensive account of the design and managment of deep-space missions, the spacecraft involved - some flown, others not - their instruments, and their scientific results. This third volume in the series covers launches in the period 1997 to 2003 and features: - a chapter entirely devoted to the Cassini-Huygens mission to Saturn; - coverage of planetary missions of the period, including the Deep Space 1 mission and the Stardust and Hayabusa sample returns from comets and asteroids; - extensive coverage of Mars exploration, the failed 1999 missions, Mars Odyssey, Mars Express, and the twin rovers Spirit and Opportunity. The story will continue in Part 4.

  8. Chemical Composition by the APXS along the Downhill Traverse of the Mars Exploration Rover Spirit at Gusev Crater

    Science.gov (United States)

    Bruckner, J.; Dreibus, G.; Gellert, R.; Clark, B.C.; Cohen, B.; McCoy, T.; Ming, D.W.; Mittlefehldt, D.W.; Yen, A.; Athena Science Team

    2006-01-01

    The Alpha Particle X-ray Spectrometer (APXS) onboard the Mars Exploration Rover Spirit continues to determine the elemental composition of samples at Gusev Crater. Starting around sol 600 the rover descended Husband Hill, which is part of the Columbia Hills, visited the inner basin with a large dune field, called 'El Dorado', and parked at Low Ridge to conserve energy during the martian winter. Many unique samples were discovered by the instruments onboard Spirit during her downhill traverse. Here, we report only on the chemical data obtained by the APXS. The compositions of some of the soil samples are comparable to the mean soil determined along the earlier traverse. However, a light-toned subsurface sample (disturbed by the rover wheels), called Dead Sea Samra , showed the highest sulfur content of all soil samples, the lowest Na, Mg, Al, Cl, K, Ca, Ti, Mn, and Zn, among the lowest Si and P, and among the highest Cr, Fe and Ni. Assuming ferric sulfate as a major mineral, large amounts of a pure silica phase must be present. Color and quantity of Dead Sea Samra resemble somewhat an earlier soil called Paso Robles , though the latter is a mixture of sulfates with phosphate-rich soil. Manganese in Dead Sea Samra is so low that the Fe/Mn ratio exceeds 300, a value that has never been found previously on Mars (Fe/Mn ratio of 46 for Gusev basalts), indicating that only Fe(3+) occurs. The dune field El Dorado contained granulated material that exhibited the highest Mg and Ni concentrations and the lowest S and Cl compared to all other soils implying an enrichment of olivine-rich sands. Two outcrops, called Algonquin and Comanche , revealed compositions that differ significantly from those of earlier outcrops as they have the highest concentrations of Mg, Fe, and Ni (except for Ni in Independence) and the lowest of Al, K (detection limit), Ca, and Ti of all brushed and almost all abraded rocks. Normative estimates assign them the highest olivine contents ever found for

  9. Chemical Composition by the APXS along the Downhill Traverse of the Mars Exploration Rover Spirit at Gusev Crater

    Science.gov (United States)

    Brueckner, J.; Dreibus, G.; Gellert, R.; Clark, B. C.; Cohen, B.; McCoy, T.; Ming, D. W.; Mittlefehldt, D. W.; Yen, A.; Team, A. S.

    2006-12-01

    The Alpha Particle X-ray Spectrometer (APXS) onboard the Mars Exploration Rover Spirit continues to determine the elemental composition of samples at Gusev Crater. Starting around sol 600 the rover descended Husband Hill, which is part of the Columbia Hills, visited the inner basin with a large dune field, called `El Dorado', and parked at `Low Ridge' to conserve energy during the martian winter. Many unique samples were discovered by the instruments onboard Spirit during her downhill traverse. Here, we report only on the chemical data obtained by the APXS. The compositions of some of the soil samples are comparable to the mean soil determined along the earlier traverse. However, a light-toned subsurface sample (disturbed by the rover wheels), called `Dead Sea Samra', showed the highest sulfur content of all soil samples, the lowest Na, Mg, Al, Cl, K, Ca, Ti, Mn, and Zn, among the lowest Si and P, and among the highest Cr, Fe and Ni. Assuming ferric sulfate as a major mineral, large amounts of a pure silica phase must be present. Color and quantity of Dead Sea Samra resemble somewhat an earlier soil called `Paso Robles', though the latter is a mixture of sulfates with phosphate-rich soil. Manganese in Dead Sea Samra is so low that the Fe/Mn ratio exceeds 300, a value that has never been found previously on Mars (Fe/Mn ratio of 46 for Gusev basalts), indicating that only Fe3+ occurs. The dune field El Dorado contained granulated material that exhibited the highest Mg and Ni concentrations and the lowest S and Cl compared to all other soils implying an enrichment of olivine-rich sands. Two outcrops, called `Algonquin' and `Comanche', revealed compositions that differ significantly from those of earlier outcrops as they have the highest concentrations of Mg, Fe, and Ni (except for Ni in `Independence') and the lowest of Al, K (detection limit), Ca, and Ti of all brushed and almost all abraded rocks. Normative estimates assign them the highest olivine contents ever

  10. Recurring Slope Lineae (RSL) and Future Exploration of Mars and Europa

    Science.gov (United States)

    McEwen, Alfred S.

    2014-11-01

    Recurring slope lineae (RSL) are narrow (canyons of Valles Marineris; some of these lineae are over 1 km long, again usually following pristine gullies. The fans on which many RSL terminate have distinctive color and spectral properties, but lack water absorption bands in MRO/CRISM. RSL are active at places with peak surface temperatures >250 K, but we do not know what time of day they are active. Laboratory experiments show that water or brines darken basaltic soils but produce weak water absorption bands after partial dehydration during the low-humidity middle afternoon conditions when MRO observes. The primary question is whether RSL are really due to water at or near the surface. All observations can be explained in this way, and no entirely dry model has been offered, but there is no direct detection of water. If they are due to water, where does the water come from and how is it replenished each year? Multiple hypotheses exist. RSL may be evidence for seepage of water today, and may mark the most promising sites to search for extraterrestrial life. There are 2 key unknowns: (1) Does the water originate from the subsurface where microbes would be protected from radiation, or does it have an atmospheric origin and is only skin deep? (2) Is the water too salty for life as we know it? RSL occur on steep, rocky slopes on which landing is dangerous, but several concepts for surface exploration of RSL were presented in http://www.lpi.usra.edu/meetings/marsconcepts2012/. Landing in RSL sites will require additional expenses for planetary protection. For these reasons, it is important to learn as much as possible about RSL from orbital observations.

  11. Mars Wars: The Rise and Fall of the Space Exploration Initiative

    Science.gov (United States)

    Hogan, Thor

    2007-08-01

    The rise of Space Exploration Initiative (SEI) and its eventual demise represents one of the landmark episodes in the history of the American space program ranking with the creation of NASA, the decision to go to the Moon, the post-Apollo planning process, and the space station decision. The story of this failed initiative is one shaped by key protagonists and critical battles. It is a tale of organizational, cultural, and personal confrontation. Organizational skirmishes involved the Space Council versus NASA, the White House versus congressional appropriators, and the Johnson Space Center versus the rest of the space agency all seeking control of the national space policy process. Cultural struggles pitted the increasingly conservative engineering ethos of NASA against the faster, better, cheaper philosophy of a Space Council looking for innovative solutions to technical problems. Personality clashes matched Vice President Dan Quayle and Space Council Executive Secretary Mark Albrecht against NASA Administrator Dick Truly and Johnson Space Center Director Aaron Cohen. In the final analysis, the demise of SEI was a classic example of a defective decision-making process one that lacked adequate high-level policy guidance, failed to address critical fiscal constraints, developed inadequate programmatic alternatives, and garnered no congressional support. Some space policy experts have argued that SEI was doomed to fail, due primarily to the immense budgetary pressures facing the nation during the early 1990's. This book will argue, however, that the failure of the initiative was not predetermined; instead, it was the result of a deeply flawed policy process that failed to develop (or even consider) policy options that may have been politically acceptable given the existing political environment.

  12. In-situ resource utilization for the human exploration of Mars : a Bayesian approach to valuation of precursor missions

    Science.gov (United States)

    Smith, Jeffrey H.

    2006-01-01

    The need for sufficient quantities of oxygen, water, and fuel resources to support a crew on the surface of Mars presents a critical logistical issue of whether to transport such resources from Earth or manufacture them on Mars. An approach based on the classical Wildcat Drilling Problem of Bayesian decision theory was applied to the problem of finding water in order to compute the expected value of precursor mission sample information. An implicit (required) probability of finding water on Mars was derived from the value of sample information using the expected mass savings of alternative precursor missions.

  13. Rapid Biochemical Analysis on the International Space Station (ISS): Preparing for Human Exploration of the Moon and Mars

    Science.gov (United States)

    Maule, J.; Morris, Heather; Monaco, L.; Steele, A.; Wainwright, N.

    2008-01-01

    . The goals of this initial study were to i) test the cleanliness of reagents/supplies on orbit, ii) test the crew's ability to collect and process a sample in microgravity without contamination, iii) demonstrate nominal function of the LOCAD-PTS, and iv) provide a general survey of endotoxin within the ISS. The surface sites varied greatly in terms of their frequency-of-use and material texture/composition; from relatively smooth aluminum, to fabric, to the room temperature vulcanizing (RTV) rubber of a Extravehicular Mobility Unit (EMU) spacesuit. Results showed that: i) the swabbing kits and reagents remained clean on orbit, ii) the crew could collect and process a sample without contamination, and iii) the LOCAD-PTS functioned nominally in > 99% of the 55 tests completed. We will present detailed results of the survey of endotoxin on ISS surfaces. These results and technology are important in the near-term - by providing an extra tool in the toolbox for ISS microbial monitoring. They are also important in the longer term as valuable preparation for human exploration of the Moon and Mars. One of the proposed science goals for the human exploration of Mars will be to detect and characterize any indigenous biological molecules that may exist on the Martian surface. To achieve that goal, the crew must have the technology available onboard to differentiate indigenous biology from any terrestrial biological material brought to Mars by the spacecraft and crew (termed 'forward contamination'). The LAL assay is already one of the official methods used by NASA's planetary protection program to certify cleanliness of interplanetary robotic spacecraft prior to launch; and therefore endotoxin is a good marker of forward contamination (as well as other microbial molecules detectable with LOCAD-PTS e.g. box-1, 3-glucan and lipoteichoic acid). Furthermore, the distribution and abundance of these molecules on the ISS provides a good indicator of what to expect on the Crew

  14. Wind-driven particle mobility on Mars: Insights from Mars Exploration Rover observations at "El Dorado" and surroundings at Gusev Crater

    Science.gov (United States)

    Sullivan, R.; Arvidson, R.; Bell, J.F.; Gellert, Ralf; Golombek, M.; Greeley, R.; Herkenhoff, K.; Johnson, J.; Thompson, S.; Whelley, P.; Wray, J.

    2008-01-01

    The ripple field known as 'El Dorado' was a unique stop on Spirit's traverse where dust-raising, active mafic sand ripples and larger inactive coarse-grained ripples interact, illuminating several long-standing issues of Martian dust mobility, sand mobility, and the origin of transverse aeolian ridges. Strong regional wind events endured by Spirit caused perceptible migration of ripple crests in deposits SSE of El Dorado, erasure of tracks in sandy areas, and changes to dust mantling the site. Localized thermal vortices swept across El Dorado, leaving paths of reduced dust but without perceptibly damaging nearly cohesionless sandy ripple crests. From orbit, winds responsible for frequently raising clay-sized dust into the atmosphere do not seem to significantly affect dunes composed of (more easily entrained) sand-sized particles, a long-standing paradox. This disparity between dust mobilization and sand mobilization on Mars is due largely to two factors: (1) dust occurs on the surface as fragile, low-density, sand-sized aggregates that are easily entrained and disrupted, compared with clay-sized air fall particles; and (2) induration of regolith is pervasive. Light-toned bed forms investigated at Gusev are coarse-grained ripples, an interpretation we propose for many of the smallest linear, light-toned bed forms of uncertain origin seen in high-resolution orbital images across Mars. On Earth, wind can organize bimodal or poorly sorted loose sediment into coarse-grained ripples. Coarse-grained ripples could be relatively common on Mars because development of durable, well-sorted sediments analogous to terrestrial aeolian quartz sand deposits is restricted by the lack of free quartz and limited hydraulic sediment processing. Copyright 2008 by the American Geophysical Union.

  15. The Highland Terrain Hopper: a new locomotion system for exploration of Mars and other low-gravity planetary bodies

    Science.gov (United States)

    Gurgurewicz, Joanna; Grygorczuk, Jerzy; Wisniewski, Lukasz; Mege, Daniel; Rickman, Hans

    Field geoscientists need to collect three-dimensional data in order characterise the lithologic succession and structure of terrains, reconstruct their evolution, and eventually reveal the history of a portion of the planet. This is achieved by walking up and down mountains and valleys, conducting and interpreting geological and geophysical traverses, and reading measures made at station located at key sites on mountain peaks or rocky promontories. These activities have been denied to conventional planetary exploration rovers because engineering constraints for landing are strong, especially in terms of allowed terrain roughness and slopes. There are few limitations in the type of scientific payload conventional exploration rovers can carry, from geology and geophysics to geochemistry and exobiology. They lack two skills, however: the ability of working on rugged or unstable terrain, like in canyons and mountains, and on solid bodies having gravity too low for the friction between the wheels and the ground to generate robot displacement. ASTRONIKA Ltd. and the Space Research Centre of the Polish Academy of Sciences are designing Galago, the Highland Terrain Hopper, a small (Ø~50-100 cm), light (5-10 kg), and robust locomotion system, which addresses the challenge of accessing most areas on low-gravity planetary body for performing scientific observations and measurements, alone or as part of a commando. Galago is symmetric and can jump accurately to a height of 4.5 m on Mars, 9 m on the Moon, and much more on Phobos and other small bodies. For one Galago, a nominal horizontal travel distance of 5 km (1000 jumps) is currently planned with the considered energy source, a battery reloaded by solar panels. Galago may assist other types of robots, or humans, in accessing difficult terrain, or even replace them for specific measurements or campaigning. Its three independent legs make possible several types of motions: accurate jumping (to any place identified in advance

  16. 火星探测无入机任务规划与建模分析%Mission Planning and Modeling Analysis for Unmanned Aerial Exploration Vehicle on Mars

    Institute of Scientific and Technical Information of China (English)

    姚克明; 王小兰; 刘燕斌; 陆宇平; 肖地波

    2012-01-01

    With the development of socio-economy and technology, more and more people from various countries pay more attention to deep-space exploration. Mars is the closest planet where life is possible. So, Mars exploration is a hot issue on international deep space exploration in recent years. There are many advantages for the use of unmanned aerial exploration vehicles on Mars, including the wide range of exploration, the visualization of terrain changes, etc. In this paper, the overall mission planning is described for unmanned aerial exploration vehicle on Mars, and the difference between flight on earth and on Mars is discussed. Then the longitudinal nonlinear model is established for unmanned aerial exploration vehicle on Mars, and Taylor expansion is applied to the nonlinear model at the trim point, hence to obtain the linear model. By further analysis of the linear model, the stable performance and flight characteristics have been grasped for unmanned aerial exploration vehicle on Mars. These work will provide the platform for the follow-up research for Mars Unmanned Aerial Vehicle (UAV) navigation and control method.%利用无人机进行火星探测,具有探测范围广、可看到地形变化等优点.介绍了火星探测无人机总体任务规划的情况,讨论了探测无人机在火星与地球上飞行的区别,建立了火星探测无人机纵向非线性模型,并在平衡点对非线性模型进行泰勒展开,得到线性化模型.通过对线性模型的进一步分析,掌握了火星探测无人机的稳态性能及飞行特点.

  17. Utilizing twins as controls for non-twin case-materials in genome wide association studies.

    Directory of Open Access Journals (Sweden)

    Andrea Ganna

    Full Text Available Twin registries around the globe have collected DNA samples from large numbers of monozygotic and dizygotic twins. The twin sample collections are frequently used as controls in disease-specific studies together with non-twins. This approach is unbiased under the hypothesis that twins and singletons are comparable in terms of allele frequencies; i.e. there are no genetic variants associated with being a twin per se. To test this hypothesis we performed a genome-wide association study comparing the allele frequency of 572,352 single nucleotide polymorphisms (SNPs in 1,413 monozygotic (MZ and 5,451 dizygotic (DZ twins with 3,720 healthy singletons. Twins and singletons have been genotyped using the same platform. SNPs showing association with being a twin at P-value < 1 × 10(-5 were selected for replication analysis in 1,492 twins (463 MZ and 1,029 DZ and 1,880 singletons from Finland. No SNPs reached genome-wide significance (P-value < 5 × 10(-8 in the main analysis combining MZ and DZ twins. In a secondary analysis including only DZ twins two SNPs (rs2033541 close to ADAMTSL1 and rs4149283 close to ABCA1 were genome-wide significant after meta-analysis with the Finnish population. The estimated proportion of variance on the liability scale explained by all SNPs was 0.08 (P-value=0.003 when MZ and DZ were considered together and smaller for MZ (0.06, P-value=0.10 compared to DZ (0.09, P-value=0.003 when analyzed separately. In conclusion, twins and singletons can be used in genetic studies together with general population samples without introducing large bias. Further research is needed to explore genetic variances associated with DZ twinning.

  18. Chromatographic, Spectroscopic and Mass Spectrometric Approaches for Exploring the Habitability of Mars in 2012 and Beyond with the Curiosity Rover

    Science.gov (United States)

    Mahaffy, Paul

    2012-01-01

    The Sample Analysis at Mars (SAM) suite of instruments on the Curiosity Rover of Mars Science Laboratory Mission is designed to provide chemical and isotopic analysis of organic and inorganic volatiles for both atmospheric and solid samples. The goals of the science investigation enabled by the gas chromatograph mass spectrometer and tunable laser spectrometer instruments of SAM are to work together with the other MSL investigations is to quantitatively assess habitability through a series of chemical and geological measurements. We describe the multi-column gas chromatograph system employed on SAM and the approach to extraction and analysis of organic compounds that might be preserved in ancient martian rocks.

  19. Twin Jet

    Science.gov (United States)

    Henderson, Brenda; Bozak, Rick

    2010-01-01

    Many subsonic and supersonic vehicles in the current fleet have multiple engines mounted near one another. Some future vehicle concepts may use innovative propulsion systems such as distributed propulsion which will result in multiple jets mounted in close proximity. Engine configurations with multiple jets have the ability to exploit jet-by-jet shielding which may significantly reduce noise. Jet-by-jet shielding is the ability of one jet to shield noise that is emitted by another jet. The sensitivity of jet-by-jet shielding to jet spacing and simulated flight stream Mach number are not well understood. The current experiment investigates the impact of jet spacing, jet operating condition, and flight stream Mach number on the noise radiated from subsonic and supersonic twin jets.

  20. Mars Museum Visualization Alliance

    Science.gov (United States)

    Sohus, A. M.; Viotti, M. A.; de Jong, E. M.

    2004-11-01

    The Mars Museum Visualization Alliance is a collaborative effort funded by the Mars Public Engagement Office and supported by JPL's Informal Education staff and the Solar System Visualization Project to share the adventure of exploration and make Mars a real place. The effort started in 2002 with a small working group of museum professionals to learn how best to serve museum audiences through informal science educators. By the time the Mars Exploration Rovers landed on Mars in January 2004, over 100 organizations were partners in the Alliance, which has become a focused community of Mars educators. The Alliance provides guaranteed access to images, information, news, and resources for use by the informal science educators with their students, educators, and public audiences. Thousands of people have shared the adventure of exploring Mars and now see it as a real place through the efforts of the Mars Museum Visualization Alliance partners. The Alliance has been lauded for "providing just the right inside track for museums to do what they do best," be that webcasts, live presentations with the latest images and information, high-definition productions, planetarium shows, or hands-on educational activities. The Alliance is extending its mission component with Cassini, Genesis, Deep Impact, and Stardust. The Mars Exploration and Cassini Programs, as well as the Genesis, Deep Impact, and Stardust Projects, are managed for NASA by the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California.

  1. Ground Contact Model for Mars Science Laboratory Mission Simulations

    Science.gov (United States)

    Raiszadeh, Behzad; Way, David

    2012-01-01

    The Program to Optimize Simulated Trajectories II (POST 2) has been successful in simulating the flight of launch vehicles and entry bodies on earth and other planets. POST 2 has been the primary simulation tool for the Entry Descent, and Landing (EDL) phase of numerous Mars lander missions such as Mars Pathfinder in 1997, the twin Mars Exploration Rovers (MER-A and MER-B) in 2004, Mars Phoenix lander in 2007, and it is now the main trajectory simulation tool for Mars Science Laboratory (MSL) in 2012. In all previous missions, the POST 2 simulation ended before ground impact, and a tool other than POST 2 simulated landing dynamics. It would be ideal for one tool to simulate the entire EDL sequence, thus avoiding errors that could be introduced by handing off position, velocity, or other fight parameters from one simulation to the other. The desire to have one continuous end-to-end simulation was the motivation for developing the ground interaction model in POST 2. Rover landing, including the detection of the postlanding state, is a very critical part of the MSL mission, as the EDL landing sequence continues for a few seconds after landing. The method explained in this paper illustrates how a simple ground force interaction model has been added to POST 2, which allows simulation of the entire EDL from atmospheric entry through touchdown.

  2. The Mars Surveyor '01 Rover and Robotic Arm

    Science.gov (United States)

    Bonitz, Robert G.; Nguyen, Tam T.; Kim, Won S.

    1999-01-01

    The Mars Surveyor 2001 Lander will carry with it both a Robotic Arm and Rover to support various science and technology experiments. The Marie Curie Rover, the twin sister to Sojourner Truth, is expected to explore the surface of Mars in early 2002. Scientific investigations to determine the elemental composition of surface rocks and soil using the Alpha Proton X-Ray Spectrometer (APXS) will be conducted along with several technology experiments including the Mars Experiment on Electrostatic Charging (MEEC) and the Wheel Abrasion Experiment (WAE). The Rover will follow uplinked operational sequences each day, but will be capable of autonomous reactions to the unpredictable features of the Martian environment. The Mars Surveyor 2001 Robotic Arm will perform rover deployment, and support various positioning, digging, and sample acquiring functions for MECA (Mars Environmental Compatibility Assessment) and Mossbauer Spectrometer experiments. The Robotic Arm will also collect its own sensor data for engineering data analysis. The Robotic Arm Camera (RAC) mounted on the forearm of the Robotic Arm will capture various images with a wide range of focal length adjustment during scientific experiments and rover deployment

  3. Exploration of Mars using Delta Differential One-Way Ranging based on Triangle Libration Points in the Earth-Moon system

    Science.gov (United States)

    Liu, Peng; Tang, Jingshi; Hou, Xiyun; Liu, Lin

    Very Long Baseline Interferometry (VLBI) is a technique that allows determination of angular position for distant radio sources by measuring the geometric time delay between received radio signals at two geographically separated stations. An application of VLBI is spacecraft navigation in space missions where delay measurements of a spacecraft radio signal are compared against similar delay measurements of angularly nearby quasar radio signals. In the case where the spacecraft measurements are obtained from the phases of tones emitted from the spacecraft, first detected separately at each station, and then differenced, this application of VLBI is known as Delta Differential One-Way Ranging (Delta-DOR). Even though data acquisition and processing are not identical for the spacecraft and quasar, they have similar information content and similar sensitivity to sources of error. Consequently, the Delta-DOR can be used in conjunction with Doppler and ranging data to improve spacecraft navigation by more efficiently determining spacecraft angular position in the plane-of-sky. Over the decades, human exploration of Mars have never been stopped. As we know, Delta-DOR began to serve its purpose for Mars Odyssey spacecraft in 2001. In the following years, Delta-DOR was used from Mars Exploration Rover (MER) in 2003-2004 to Mars Science Laboratory (MSL) in 2011, all with excellent results. At present, human exploration of Mars using Delta-DOR technique mainly depends on the Earth-based ground stations. As we know, the differential time delay between the spacecraft and quasar is given approximately by begin{math}Deltatau=-frac{1}{c}BsinTheta_{1}(DeltaTheta_{B}) , the accuracy of the determination of angular separation begin{math}DeltaTheta_{B} improves as the measurement error in the observable begin{math}Deltatau decreases. Further, begin{math}DeltaTheta_{B} accuracy improves as the baseline length B increases. Therefore, the introduction of special libration points, i

  4. Performance Testing of Lithium Li-ion Cells and Batteries in Support of JPL's 2003 Mars Exploration Rover Mission

    Science.gov (United States)

    Smart, Marshall C.; Ratnakumar, B. V.; Ewell, R. C.; Whitcanack, L. D.; Surampudi, S.; Puglia, F.; Gitzendanner, R.

    2007-01-01

    In early 2004, JPL successfully landed two Rovers, named Spirit and Opportunity, on the surface of Mars after traveling > 300 million miles over a 6-7 month period. In order to operate for extended duration on the surface of Mars, both Rovers are equipped with rechargeable Lithium-ion batteries, which were designed to aid in the launch, correct anomalies during cruise, and support surface operations in conjunction with a triple-junction deployable solar arrays. The requirements of the Lithium-ion battery include the ability to provide power at least 90 sols on the surface of Mars, operate over a wide temperature range (-20(super 0)C to +40(super 0)C), withstand long storage periods (e.g., including pre-launch and cruise period), operate in an inverted position, and support high currents (e.g., firing pyro events). In order to determine the inability of meeting these requirements, ground testing was performed on a Rover Battery Assembly Unit RBAU), consisting of two 8-cell 8 Ah lithium-ion batteries connected in parallel. The RBAU upon which the performance testing was performed is nearly identical to the batteries incorporated into the two Rovers currently on Mars. The primary focus of this paper is to communicate the latest results regarding Mars surface operation mission simulation testing, as well as, the corresponding performance capacity loss and impedance characteristics as a function of temperature and life. As will be discussed, the lithium-ion batteries (fabricated by Yardney Technical Products, Inc.) have been demonstrated to far exceed the requirements defined by the mission, being able to support the operation of the rovers for over three years, and are projected to support an even further extended mission.

  5. Deformation twinning in monazite

    Energy Technology Data Exchange (ETDEWEB)

    Hay, R.S.; Marshall, D.B

    2003-10-20

    Polycrystalline monazite (LaPO{sub 4}) was deformed at room temperature by a spherical indenter. Deformation twins were identified by TEM in 70 grains. Five twin planes were found: (100) was by far the most common; (001) and (120) were less common; (122-bar)was rare, and kinks in (120) twins were identified as irrational '(483)' twin planes. The twinning modes on these planes were inferred from the expression of twinning shear at free surfaces, predictions of classical deformation twinning theory, and various considerations of twin morphology and crystal structure. Atomic shuffle calculations that allow formation of either a glide plane or a mirror plane at the twin interface were used to analyze twin modes. The inferred twin modes all have small atomic shuffles. For (001) twins, the smallest shuffles were obtained with a glide plane at the interface, with displacement vector R=((1)/(2))[010]. The results do not uniquely define a twin mode on (100), leaving open the possibility of more than one mode operating on this plane. Factors that may determine the operative deformation twinning modes are discussed. Crystal structure considerations suggest that the relative abundance of twinning modes may correlate with low shear modulus on the twin plane in the direction of twinning shear, and with a possible low-energy interface structure consisting of a layer of xenotime of one half-unit-cell thickness that could form at (100) and (001) twins. The three most common twins have low strains to low {sigma} coincidence site lattices (CSLs)

  6. 精确动力学模型下的火星探测轨道设计%Orbit Design for Mars Exploration by the Accurate Dynamic Model

    Institute of Scientific and Technical Information of China (English)

    陈杨; 赵国强; 宝音贺西; 李俊峰

    2011-01-01

    The precision orbit design for Mars exploration by the accurate dynamic model was studied. The launch window and trans-Mars orbit was determined through the partical swarm optimization (PSO) algorithm within the heliocentric two-body restriction. The patched conics method was introduced to design the earth-centred parking orbit and departure hyperbolic orbit. The solution of two-body Lambert problem was input as initial value for precision orbit design, and the preliminary orbit was corrected with the restrictions of the Mars B-plane parameters and flight time by the accurate dynamic model. Finally the designed orbit was simulated with the STK softwares.%首先在二体意义下采用粒子群优化算法(PSO)求解Lambert问题,确定发射窗口和二体地火转移轨道.使用圆锥曲线拼接法设计地心停泊轨道、逃逸轨道,并作为轨道精确设计的初值,以建立在火星的B平面参数和地火转移时间为约束,在精确动力学模型下进行微分迭代修正,最终得到满足约束的精确轨道.将设计轨道在STK软件中仿真,结果吻合.

  7. Study on Nuclear Thermal Rocket for Manned Mars Exploration%载人核热火箭登陆火星方案研究

    Institute of Scientific and Technical Information of China (English)

    洪刚; 娄振; 郑孟伟; 王建明

    2015-01-01

    With the high-speed development of space technology in the 21st century, the main space faring counties have proposed manned Mars exploration initiatives in 2030 s.In this article , the ad-vantages and disadvantages of chemical , electrical and nuclear rocket were compared at first .It was found that nuclear thermal rocket ( NTR) technology was the best choice for future manned Mars ex-ploration .Then , the development history of nuclear thermal rocket in US and Russia was reviewed , and the nuclear thermal/electrical bimodal technological trend was presented .Finally, Chinese prime human mars exploration architecture , crew/cargo separation and 5-times LEO docking , were proposed .Based on this architecture , a 15 t single-thrust and 940 s impulse nuclear thermal engine was designed and Chinese NTR development-research plan between 2016 and 2035 was presented .%针对未来载人登陆火星任务,比较了化学推进、电推进及核推进的优缺点,指出核热推进是未来载人登陆火星的首选. 简述了美国和俄罗斯在核热推进的研究进展,指出核热/发电双模式是未来载人登火的发展趋势. 提出我国近地轨道5次对接、人货分离载人登陆火星构想.在此基础上,设计了单台推力15 t,比冲940 s载人核热发动机并提出我国核热火箭2016—2035年发展研究规划.

  8. How specific is second language-learning ability? A twin study exploring the contributions of first language achievement and intelligence to second language achievement.

    Science.gov (United States)

    Rimfeld, K; Dale, P S; Plomin, R

    2015-09-22

    Learning a second language is crucially important in an increasingly global society, yet surprisingly little is known about why individuals differ so substantially in second language (SL) achievement. We used the twin design to assess the nature, nurture and mediators of individual differences in SL achievement. For 6263 twin pairs, we analyzed scores from age 16 UK-wide standardized tests, the General Certificate of Secondary Education (GCSE). We estimated genetic and environmental influences on the variance of SL for specific languages, the links between SL and English and the extent to which the links between SL and English are explained by intelligence. All SL measures showed substantial heritability, although heritability was nonsignificantly lower for German (36%) than the other languages (53-62%). Multivariate genetic analyses indicated that a third of genetic influence in SL is shared with intelligence, a third with English independent of intelligence and a further third is unique to SL.

  9. The Norwegian Twin Registry.

    Science.gov (United States)

    Nilsen, Thomas S; Brandt, Ingunn; Magnus, Per; Harris, Jennifer R

    2012-12-01

    Norway has a long-standing tradition in twin research, but the data collected in several population-based twin studies were not coordinated centrally or easily accessible to the scientific community. In 2009, the Norwegian Twin Registry was established at the Norwegian Institute of Public Health (NIPH) in Oslo with the purpose of creating a single research resource for Norwegian twin data. As of today, the Norwegian Twin Registry contains 47,989 twins covering birth years 1895-1960 and 1967-1979; 31,440 of these twins consented to participate in health-related research. In addition, DNA from approximately 4,800 of the twins is banked at the NIPH biobank and new studies are continually adding new data to the registry. The value of the Norwegian twin data is greatly enhanced by the linkage opportunities offered by Norway's many nationwide registries, spanning a broad array of medical, demographic, and socioeconomic information.

  10. A new analysis of Mars "Special Regions": findings of the second MEPAG Special Regions Science Analysis Group (SR-SAG2).

    Science.gov (United States)

    Rummel, John D; Beaty, David W; Jones, Melissa A; Bakermans, Corien; Barlow, Nadine G; Boston, Penelope J; Chevrier, Vincent F; Clark, Benton C; de Vera, Jean-Pierre P; Gough, Raina V; Hallsworth, John E; Head, James W; Hipkin, Victoria J; Kieft, Thomas L; McEwen, Alfred S; Mellon, Michael T; Mikucki, Jill A; Nicholson, Wayne L; Omelon, Christopher R; Peterson, Ronald; Roden, Eric E; Sherwood Lollar, Barbara; Tanaka, Kenneth L; Viola, Donna; Wray, James J

    2014-11-01

    A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms might replicate (per the COSPAR Planetary Protection Policy). This review and update was conducted by an international team (SR-SAG2) drawn from both the biological science and Mars exploration communities, focused on understanding when and where Special Regions could occur. The study applied recently available data about martian environments and about terrestrial organisms, building on a previous analysis of Mars Special Regions (2006) undertaken by a similar team. Since then, a new body of highly relevant information has been generated from the Mars Reconnaissance Orbiter (launched in 2005) and Phoenix (2007) and data from Mars Express and the twin Mars Exploration Rovers (all 2003). Results have also been gleaned from the Mars Science Laboratory (launched in 2011). In addition to Mars data, there is a considerable body of new data regarding the known environmental limits to life on Earth-including the potential for terrestrial microbial life to survive and replicate under martian environmental conditions. The SR-SAG2 analysis has included an examination of new Mars models relevant to natural environmental variation in water activity and temperature; a review and reconsideration of the current parameters used to define Special Regions; and updated maps and descriptions of the martian environments recommended for treatment as "Uncertain" or "Special" as natural features or those potentially formed by the influence of future landed spacecraft. Significant changes in our knowledge of the capabilities of terrestrial organisms and the existence of possibly habitable martian environments have led to a new appreciation of where Mars Special Regions may be identified and protected. The SR-SAG also considered the impact of Special Regions on potential future human missions to Mars, both as locations of

  11. A new analysis of Mars "Special Regions": findings of the Second MEPAG Special Regions Science Analysis Group (SR-SAG2)

    Science.gov (United States)

    Rummel, John D.; Beaty, David W.; Jones, Melissa A.; Bakermans, Corien; Barlow, Nadine G.; Boston, Penelope J.; Chevrier, Vincent F.; Clark, Benton C.; de Vera, Jean-Pierre P.; Gough, Raina V.; Hallsworth, John E.; Head, James W.; Hipkin, Victoria J.; Kieft, Thomas L.; McEwen, Alfred S.; Mellon, Michael T.; Mikucki, Jill A.; Nicholson, Wayne L.; Omelon, Christopher R.; Peterson, Ronald; Roden, Eric E.; Lollar, Barbara Sherwood; Tanaka, Kenneth L.; Viola, Donna; Wray, James J.

    2014-01-01

    A committee of the Mars Exploration Program Analysis Group (MEPAG) has reviewed and updated the description of Special Regions on Mars as places where terrestrial organisms might replicate (per the COSPAR Planetary Protection Policy). This review and update was conducted by an international team (SR-SAG2) drawn from both the biological science and Mars exploration communities, focused on understanding when and where Special Regions could occur. The study applied recently available data about martian environments and about terrestrial organisms, building on a previous analysis of Mars Special Regions (2006) undertaken by a similar team. Since then, a new body of highly relevant information has been generated from the Mars Reconnaissance Orbiter (launched in 2005) and Phoenix (2007) and data from Mars Express and the twin Mars Exploration Rovers (all 2003). Results have also been gleaned from the Mars Science Laboratory (launched in 2011). In addition to Mars data, there is a considerable body of new data regarding the known environmental limits to life on Earth—including the potential for terrestrial microbial life to survive and replicate under martian environmental conditions. The SR-SAG2 analysis has included an examination of new Mars models relevant to natural environmental variation in water activity and temperature; a review and reconsideration of the current parameters used to define Special Regions; and updated maps and descriptions of the martian environments recommended for treatment as "Uncertain" or "Special" as natural features or those potentially formed by the influence of future landed spacecraft. Significant changes in our knowledge of the capabilities of terrestrial organisms and the existence of possibly habitable martian environments have led to a new appreciation of where Mars Special Regions may be identified and protected. The SR-SAG also considered the impact of Special Regions on potential future human missions to Mars, both as locations

  12. An integrated geophysical survey of Kilbourne Hole, southern New Mexico: Implications for near surface exploration of Mars and the Moon

    Science.gov (United States)

    Maksim, Nisa

    Features such as the Home Plate plateau on Mars, a suspected remnant of an ancient phreatomagmatic eruption, can reveal important information about paleohydrologic conditions. The eruption intensity of a phreatomagmatic volcano is controlled mainly by the quantity of water and magma, the internal geometry of the volcano, and the depth of the interaction zone between magma and water. In order to understand the paleohydrologic conditions at the time of eruption, we must understand all the factors that influenced the phreatomagmatic event. I conducted an integrated geophysical survey, which are magnetic and gravity surveys, and a ground-penetrating radar (GPR) surveys at Kilbourne Hole, a phreatomagmatic crater in southern New Mexico. These investigations serve an analog paleo-hydrogeological study that could be conducted on Mars and the Moon with an implication for planetary exploration. These geophysical surveys are designed to delineate the internal structure of a phreatomagmatic volcano and to define the volumes and masses of volcanic dikes and excavation unit, the depth of feeder dikes, and impacted velocity of the volcanic blocks. For the gravity and magnetic surveys at Kilbourne Hole, I collected data at a total of 171 gravity survey stations and 166 magnetics survey stations. A 2D gravity and magnetic inverse model was developed jointly to map the body of the magma intrusions and the internal structure of Kilbourne Hole. A total of 6 GPR surveys lines were also completed at Kilbourne Hole to image and to define locations of pyroclastic deposits, volcanic sags and blocks, the sizes distribution of volcanic blocks, and the impact velocity of the volcanic blocks. Using the size distribution and impact velocity of volcanic blocks from our GPR data, I derived the initial gas expansion velocity and the time duration of the gas expansion phase of the Kilbourne Hole eruption. These obtained parameters (volumes, masses, and depths of the feeder dikes and the excavation

  13. One Martian Year of in Situ Chemistry by the APXS on Board the Mars Exploration Rover Opportunity at Meridiani Planum

    Science.gov (United States)

    Brueckner, J.; Dreibus, G.; Gellert, R.; Clark, B. C.; Klingelhoefer, G.; Lugmair, G.; Ming, D.; Rieder, R.; Waenke, H.; Yen, A.; Zipfel, J.

    2005-12-01

    Two in-situ instruments, the Alpha Particle X-ray Spectrometer (APXS) and the Moessbauer Spectrometer (MB), gathered geochemical and mineralogical data along the traverse of the Mars Exploration Rover Opportunity at Meridiani Planum. Eagle crater, the landing site of the rover, contains undisturbed soils that resemble those at Gusev crater; however, the Fe, Ni, and Cr contents and Fe/Si ratios of Meridiani soils are higher than those of Gusev soils. The enrichment of Fe results from an admixture of the mineral hematite as determined by MB. This mineral occurs as a finely disseminated component of the outcrop rocks as well as in mm- to several mm-sized spherules, nicknamed blueberries, which are spread at the landing site and along the several kilometers traverse to the Erebus crater. The formation of hematite is typically an indicator for aqueous activity under oxidizing conditions. Light-toned layered outcrops were discovered in Eagle crater and later in other craters, as well as along the rover's traverse. Most of these undisturbed rock surfaces have a factor of 2 to 3 higher S concentrations compared to the soils. In Eagle crater, ground rock surfaces (exposed by the Rock Abrasion Tool, or RAT) showed even higher S contents of up to 9.5 weight percent. Assuming all SO3 is bound to Mg and Ca sulfates and, according to MB data, to ferric sulfates, mainly jarosite, these rocks contain about 40 weight percent sulfates. High concentrations of Br were discovered in some soils excavated with the rover wheels and rocks ground with the RAT. The high abundances of S and Br in these rocks point to ancient occurrence of acidified water and the formation of brines, which could have been occasionally evaporated. Small quantities of the hematite-rich spherules (ca. 2 volume percent) were found in the rocks of Eagle crater. The acidic conditions during the formation of the hematitic spherules in the rocks as concretions allowed co-precipitation of Fe2O3 and NiO but no MnO. When

  14. Impact of Diagenesis on Biosignature Preservation Potential in Playa Lake Evaporites in Verde Formation, Arizona: Implications for Mars Exploration

    Science.gov (United States)

    Shkolyar, S.; Farmer, J. D.

    2015-12-01

    Major priorities for Mars science include assessing the preservation potential and impact of diagenesis on biosignature preservation in aqueous sedimentary environments. We address these priorities with field and lab studies of playa evaporites of the Verde Formation (upper Pliocene) in Arizona. Evaporites studied include bottom-nucleated halite and displacive growth gypsum in magnesite-rich mudstone. These lithotypes are potential analogs for ancient lacustrine habitable environments on Mars. This study aimed to understand organic matter preservation potential under different diagenetic histories. Methods combined outcrop-scale field observations and lab analyses, including: (1) thin-section petrography to understand diagenetic processes and paragenesis; (2) X-ray powder diffraction to obtain bulk mineralogy; (3) Raman spectroscopy to identify and place phases (and kerogenous fossil remains) within a microtextural context; (4) Total Organic Carbon (TOC) analyses to estimate weight percentages of preserved organic carbon for each subfacies endmember; and (5) electron microprobe to create 2D kerogen maps semi-quantifying kerogen preservation in each subfacies. Results revealed complex diagenetic histories for each evaporite subfacies and pathways for organic matter preservation. Secondary gypsum grew displacively within primary playa lake mudstones during early diagenesis. Mudstones then experienced cementation by Mg-carbonates. Displacive-growth gypsum was sometimes dissolved, forming crystal molds. These molds were later either infilled by secondary sulfates or recrystallized to gypsum pseudomorphs with minor phases present (i.e., glauberite). These observations helped define taphonomic models for organic matter preservation in each subfacies. This work has the potential to inform in situ target identification, sampling strategies, and data interpretations for future Mars Sample Return missions (e.g., sample caching strategies for NASA's Mars 2020 mission).

  15. Microscope on Mars

    Science.gov (United States)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  16. Microscope on Mars

    Science.gov (United States)

    2004-01-01

    This image taken at Meridiani Planum, Mars by the panoramic camera on the Mars Exploration Rover Opportunity shows the rover's microscopic imager (circular device in center), located on its instrument deployment device, or 'arm.' The image was acquired on the ninth martian day or sol of the rover's mission.

  17. Vehicle and Mission Design Options for the Human Exploration of Mars/Phobos Using "Bimodal" NTR and LANTR Propulsion

    Science.gov (United States)

    Borowski, Stanley K.; Dudzinski, Leonard A.; McGuire, Melissa L.

    2002-12-01

    The nuclear thermal rocket (NTR) is one of the leading propulsion options for future human missions to Mars because of its high specific impulse (1sp is approximately 850-1000 s) capability and its attractive engine thrust-to-weight ratio (approximately 3-10). To stay within the available mass and payload volume limits of a "Magnum" heavy lift vehicle, a high performance propulsion system is required for trans-Mars injection (TMI). An expendable TMI stage, powered by three 15 thousand pounds force (klbf) NTR engines is currently under consideration by NASA for its Design Reference Mission (DRM). However, because of the miniscule burnup of enriched uranium-235 during the Earth departure phase (approximately 10 grams out of 33 kilograms in each NTR core), disposal of the TMI stage and its engines after a single use is a costly and inefficient use of this high performance stage. By reconfiguring the engines for both propulsive thrust and modest power generation (referred to as "bimodal" operation), a robust, multiple burn, "power-rich" stage with propulsive Mars capture and reuse capability is possible. A family of modular bimodal NTR (BNTR) vehicles are described which utilize a common "core" stage powered by three 15 klbf BNTRs that produce 50 kWe of total electrical power for crew life support, an active refrigeration / reliquification system for long term, zero-boiloff liquid hydrogen (LH2) storage, and high data rate communications. An innovative, spine-like "saddle truss" design connects the core stage and payload element and is open underneath to allow supplemental "in-line" propellant tanks and contingency crew consumables to be easily jettisoned to improve vehicle performance. A "modified" DRM using BNTR transfer vehicles requires fewer transportation system elements, reduces IMLEO and mission risk, and simplifies space operations. By taking the next logical step--use of the BNTR for propulsive capture of all payload elements into Mars orbit--the power

  18. The Danish Twin Register

    DEFF Research Database (Denmark)

    Kyvik, K O; Christensen, Kaare; Skytthe, A;

    1996-01-01

    BACKGROUND: Population based twin registers represent a valuable tool for genetic epidemiological research, since twin studies aim at separating the effect of genes and environment for complex traits. The Danish Twin Register's history, size, ascertainment and completeness of data, as well as data...... accessibility and availability are described. RESULTS: The Danish Twin Register comprises 14,051 twin pairs born 1870-1930, representing all twins surviving to age six years, and 20,888 twin pairs born 1953-1982, representing 75% of those born 1953-1967 and 95% of those born 1968-1982. The birth cohorts 1931......-1952 og 1983-1993 are being ascertained at the moment. The register is available for research given certain conditions are fulfilled. CONCLUSION: This register will in a few years be the most comprehensive twin register in the world. It is a very valuable Danish research resource....

  19. The Danish Twin Register

    DEFF Research Database (Denmark)

    Kyvik, K O; Christensen, Kaare; Skytthe, A

    1996-01-01

    BACKGROUND: Population based twin registers represent a valuable tool for genetic epidemiological research, since twin studies aim at separating the effect of genes and environment for complex traits. The Danish Twin Register's history, size, ascertainment and completeness of data, as well as data...... accessibility and availability are described. RESULTS: The Danish Twin Register comprises 14,051 twin pairs born 1870-1930, representing all twins surviving to age six years, and 20,888 twin pairs born 1953-1982, representing 75% of those born 1953-1967 and 95% of those born 1968-1982. The birth cohorts 1931......-1952 og 1983-1993 are being ascertained at the moment. The register is available for research given certain conditions are fulfilled. CONCLUSION: This register will in a few years be the most comprehensive twin register in the world. It is a very valuable Danish research resource....

  20. Two Years of Chemical Sampling on Meridiani Planum by the Alpha Particle X-Ray Spectrometer Onboard the Mars Exploration Rover Opportunity

    Science.gov (United States)

    Bruckner, J.; Gellert, R.; Clark, B.C.; Dreibus, G.; Rieder, R.; Wanke, H.; d'Uston, C.; Economou, T.; Klingelhofer, G.; Lugmair, G.; Ming, D.W.; Squyres, S.W.; Yen, A.; Zipfel, J.

    2006-01-01

    For over two terrestrial years, the Mars Exploration Rover Opportunity has been exploring the martian surface at Meridiani Planum using the Athena instrument payload [1], including the Alpha Particle X-Ray Spectrometer (APXS). The APXS has a small sensor head that is mounted on the robotic arm of the rover. The chemistry, mineralogy and morphology of selected samples were investigated by the APXS along with the Moessbauer Spectrometer (MB) and the Microscopic Imager (MI). The Rock Abrasion Tool (RAT) provided the possibility to dust and/or abrade rock surfaces down to several millimeters to expose fresh material for analysis. We report here on APXS data gathered along the nearly 6-kilometers long traverse in craters and plains of Meridiani.

  1. Mars Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA’s Mars Exploration Program (MEP) calls for a series of highly ambitious missions over the next decade and beyond. The overall goals of the MEP must be...

  2. Monochorionic twin pregnancies

    NARCIS (Netherlands)

    Hack, K.E.A.

    2008-01-01

    Following widespread application of assisted reproductive technology modalities and the increased age of motherhood, the incidence of twin gestations has increased markedly. Twins are either monozygotic or dizygotic. Dizygotic (i.e. fraternal) twins result from the fertilization of two different egg

  3. Nanosatellites for Interplanetary Exploration : Missions of Co-Operation and Exploration to Mars, Exo-Moons and other worlds in the Solar System

    Science.gov (United States)

    Ravi, Aditya; Radhakrishnan, Arun

    2016-07-01

    The last decade has borne witness to a large number of Nano-satellites being launched.This increasing trend is mainly down to the advancements in consumer electronics that has played a crucial role in increasing the potential power available on board for mission study and analysis whilst being much smaller in size when compared to their satellite counterparts. This overall reduction in size and weight is a crucial factor when coupled with the recent innovations in various propulsion systems and orbital launch vehicles by private players has also allowed the cost of missions to brought down to a very small budget whilst able to retain the main science objectives of a dedicated space Missions. The success of first time missions such as India's Mars Orbiter Mission and the upcoming Cube-Sat Mission to Mars has served as a catalyst and is a major eye-opener on how Interplanetary missions can be funded and initiated in small time spans. This shows that Interplanetary missions with the main objective of a scientific study can be objectified by using Dedicated Nano-satellite constellations with each satellite carrying specific payloads for various mission parameters such as Telemetry, Observation and possible small lander payloads for studying the various Atmospheric and Geo-Physical parameters of a particular object with-out the requirement of a very long term expensive Spacecraft Mission. The association of Major Universities and Colleges in building Nano and-satellites are facilitating an atmosphere of innovation and research among students in a class-room level as their creative potential will allow for experiments and innovation on a scale never imagined before. In this paper, the Author envisions the feasibility of such low cost Nano satellite missions to various bodies in the solar system and how Nano satellite partnerships from universities and space agencies from around the world could foster a new era in diplomacy and International Co-operation.

  4. Interannual, seasonal and diurnal Mars surface environmental cycles observed from Viking to Curiosity

    Science.gov (United States)

    Martinez, German; Vicente-Retortillo, Álvaro; Kemppinen, Osku; Fischer, Erik; Fairen, Alberto G.; Guzewich, Scott David; Haberle, Robert; Lemmon, Mark T.; Newman, Claire E.; Renno, Nilton O.; Richardson, Mark I.; Smith, Michael D.; De la Torre, Manuel; Vasavada, Ashwin R.

    2016-10-01

    We analyze in-situ environmental data from the Viking landers to the Curiosity rover to estimate atmospheric pressure, near-surface air and ground temperature, relative humidity, wind speed and dust opacity with the highest confidence possible. We study the interannual, seasonal and diurnal variability of these quantities at the various landing sites over a span of more than twenty Martian years to characterize the climate on Mars and its variability. Additionally, we characterize the radiative environment at the various landing sites by estimating the daily UV irradiation (also called insolation and defined as the total amount of solar UV energy received on flat surface during one sol) and by analyzing its interannual and seasonal variability.In this study we use measurements conducted by the Viking Meteorology Instrument System (VMIS) and Viking lander camera onboard the Viking landers (VL); the Atmospheric Structure Instrument/Meteorology (ASIMET) package and the Imager for Mars Pathfinder (IMP) onboard the Mars Pathfinder (MPF) lander; the Miniature Thermal Emission Spectrometer (Mini-TES) and Pancam instruments onboard the Mars Exploration Rovers (MER); the Meteorological Station (MET), Thermal Electrical Conductivity Probe (TECP) and Phoenix Surface Stereo Imager (SSI) onboard the Phoenix (PHX) lander; and the Rover Environmental Monitoring Station (REMS) and Mastcam instrument onboard the Mars Science Laboratory (MSL) rover.A thorough analysis of in-situ environmental data from past and present missions is important to aid in the selection of the Mars 2020 landing site. We plan to extend our analysis of Mars surface environmental cycles by using upcoming data from the Temperature and Wind sensors (TWINS) instrument onboard the InSight mission and the Mars Environmental Dynamics Analyzer (MEDA) instrument onboard the Mars 2020 mission.

  5. A registry of adult African American twins: the Carolina African American Twin Study of Aging.

    Science.gov (United States)

    Whitfield, Keith E

    2013-02-01

    Twin studies have seldom addressed ethnicity as one of the possible factors that create unique combinations of genetic and environmental influences. The major objective of the Carolina African American Twin Study of Aging is to identify the proportion of the genetic and environmental sources of individual variation in measures of health and behavioral factors in a sample of adult African Americans. Drawn from birth records from the State of North Carolina, this in-person study used public records to identify a cohort of twins between 22 and 92 years of age (X = 49.82 yrs, SD = 14.62), 39.7% of which were men. Members of non-intact twin pairs and siblings were also recruited to explore alternative models to the classic twin design. To date, the project has contributed to knowledge about blood pressure, forced expiratory volume, chronic illness, body mass index, and waist-hip ratio memory, personality, social, and demographic factors, mortality, and mental health.

  6. 火星探测接近段的光学自主导航研究%Research on Optical Autonomous Navigation for Approach Phase of Mars Exploration

    Institute of Scientific and Technical Information of China (English)

    崔文; 张少愚; 张树瑜; 宝音贺西

    2013-01-01

    The optical autonomous navigation has recently become one of the key topics in interplanetary space missions.According to the current research literature,most people only focused on the application of optical autonomous navigation for the cruise phase or the approach phase of asteroids exploration.The research for the approach phase of planets is rare.Based on the upcoming Mars exploration program of China,with the research of dynamics model,observation model and filtering algorithm,the process of the optical autonomous navigation during the Mars approach phase is studied.Through the observability analysis of the navigation system,the feasibility of using Mars optical information only for autonomous navigation is proved.Simulation result showed that the total time of the optical autonomous navigation for approach phase is about 40 hours.In the last 5 hours,the filtering results are becoming stable.The overall position error is less than 40 km,and the velocity error is 0.25m·s-1.The stability and accuracy of the results can meet the requirement of actual task,and is referencable for Chinese Mars exploration program.%目前光学自主导航技术已成为深空探测计划中的重点研究对象.已有研究多侧重于光学自主导航技术在深空探测巡航段或是对小行星探测接近段中的应用,而关于大行星探测接近段光学自主导航技术的研究比较少.结合中国即将开展的火星探测计划,研究了探测器在火星探测接近段中利用火星进行光学自主导航的整个过程,提出了适用于接近段的动力学模型、光学观测模型及自主导航滤波算法.通过对自主导航系统的可观测性分析,证明了仅利用火星光学信息进行自主导航的可行性.仿真计算结果表明,在接近段,整个光学自主导航的持续时间约为40 h.在自主导航的最后5h内,滤波结果稳定,探测器的总体位置误差在40 km以内,速度误差在0.25 m.s-1以内.计算结果的精度

  7. A novel method for surface exploration: Super-resolution restoration of Mars repeat-pass orbital imagery

    Science.gov (United States)

    Tao, Y.; Muller, J.-P.

    2016-02-01

    Higher resolution imaging data of planetary surfaces is considered desirable by the international community of planetary scientists interested in improving understanding of surface formation processes. However, given various physical constraints from the imaging instruments through to limited bandwidth of transmission one needs to trade-off spatial resolution against bandwidth. Even given optical communications, future imaging systems are unlikely to be able to resolve features smaller than 25 cm on most planetary bodies, such as Mars. In this paper, we propose a novel super-resolution restoration technique, called Gotcha-PDE-TV (GPT), taking advantage of the non-redundant sub-pixel information contained in multiple raw orbital images in order to restore higher resolution imagery. We demonstrate optimality of this technique in planetary image super-resolution restoration with example processing of 8 repeat-pass 25 cm HiRISE images covering the MER-A Spirit rover traverse in Gusev crater to resolve a 5 cm resolution of the area. We assess the "true" resolution of the 5 cm super-resolution restored images using contemporaneous rover Navcam imagery on the surface and an inter-comparison of landmarks in the two sets of imagery.

  8. Why Accurate Knowledge of Zygosity is Important to Twins.

    Science.gov (United States)

    Cutler, Tessa L; Murphy, Kate; Hopper, John L; Keogh, Louise A; Dai, Yun; Craig, Jeffrey M

    2015-06-01

    All same-sex dizygotic (DZ) twins and approximately one-third of monozygotic (MZ) twin pairs have separate placentas, making it impossible to use the number of placentas to determine zygosity. Zygosity determination is further complicated because incorrect assumptions are often made, such as that only DZ pairs have two placentas and that all MZ pairs are phenotypically identical. These assumptions, by twins, their families and health professionals, along with the lack of universal zygosity testing for same-sex twins, has led to confusion within the twin community, yet little research has been conducted with twins about their understanding and assumptions about zygosity. We aimed to explore and quantify understanding and assumptions about zygosity using twins attending an Australian twin festival. We recruited 91 twin pairs younger than 18 years of age and their parents, and 30 adult twin pairs who were all uncertain of their zygosity, to complete one pen and paper questionnaire and one online questionnaire about their assumed zygosity, reasons for their assumptions and the importance of accurate zygosity knowledge. Responses were compared with their true zygosity measured using a genetic test. We found a substantial proportion of parents and twins had been misinformed by their own parents or medical professionals, and that knowledge of their true zygosity status provided peace of mind and positive emotional responses. For these reasons we propose universal zygosity testing of same-sex twins as early in life as possible and an increase in education of medical professionals, twins and families of twins about zygosity issues.

  9. Malaysian Twin Registry.

    Science.gov (United States)

    Jahanfar, Shayesteh; Jaffar, Sharifah Halimah

    2013-02-01

    The National Malaysian Twin Registry was established in Royal College of Medicine, Perak, University Kuala Lumpur (UniKL) in June 2008 through a grant provided by UniKL. The general objective is to facilitate scientific research involving participation of twins and their family members in order to answer questions of health and wellbeing relevant to Malaysians. Recruitment is done via mass media, poster, and pamphlets. We now have 266 adult and 204 children twins registered. Several research projects including reproductive health study of twins and the role of co-bedding on growth and development of children are carried out. Registry holds annual activities for twins and seeks to provide health-related information for twins. We seek international collaboration.

  10. Perinatal hepatic infarction in twin-twin transfusion.

    LENUS (Irish Health Repository)

    O'Sullivan, M J

    2012-02-03

    We report a case of a twin pregnancy which was complicated by a twin-twin transfusion in which the recipient twin was noted to have an intra-abdominal echogenic mass. This twin died at two days of age of hepatic infarction. The donor twin was healthy at birth, at thirty weeks\\' gestation, and did not have any subsequent problems. Fetal intra-abdominal echogenicity may be a marker of hepatic infarction.

  11. Bioinspired engineering of exploration systems: a horizon sensor/attitude reference system based on the dragonfly Ocelli for Mars exploration applications

    Science.gov (United States)

    Thakoor, S.; Zornetzer, S.; Hine, B.; Chahl, J.; Stange, G.

    2002-01-01

    The intent of Bio-inspired Engineering of Exploration Systems (BEES) is to distill the principles found in successful, nature-tested mechanisms of specific crucial functions that are hard to accomplish by conventional methods, but accomplished rather deftly in nature by biological oganisms.

  12. The Brazilian Twin Registry.

    Science.gov (United States)

    Ferreira, Paulo H; Oliveira, Vinicius C; Junqueira, Daniela R; Cisneros, Lígia C; Ferreira, Lucas C; Murphy, Kate; Ordoñana, Juan R; Hopper, John L; Teixeira-Salmela, Luci F

    2016-12-01

    The Brazilian Twin Registry (BTR) was established in 2013 and has impelled twin research in South America. The main aim of the initiative was to create a resource that would be accessible to the Brazilian scientific community as well as international researchers interested in the investigation of the contribution of genetic and environmental factors in the development of common diseases, phenotypes, and human behavior traits. The BTR is a joint effort between academic and governmental institutions from Brazil and Australia. The collaboration includes the Federal University of Minas Gerais (UFMG) in Brazil, the University of Sydney and University of Melbourne in Australia, the Australian Twin Registry, as well as the research foundations CNPq and CAPES in Brazil. The BTR is a member of the International Network of Twin Registries. Recruitment strategies used to register twins have been through participation in a longitudinal study investigating genetic and environmental factors for low back pain occurrence, and from a variety of sources including media campaigns and social networking. Currently, 291 twins are registered in the BTR, with data on demographics, zygosity, anthropometrics, and health history having been collected from 151 twins using a standardized self-reported questionnaire. Future BTR plans include the registration of thousands of Brazilian twins identified from different sources and collaborate nationally and internationally with other research groups interested on twin studies.

  13. Delivery in Twin Gestation

    Directory of Open Access Journals (Sweden)

    Mark T. Peters

    1995-01-01

    Full Text Available Objective: The objective of this study was to determine whether prophylactic treatment with oral broad-spectrum antimicrobial therapy improves pregnancy outcomes in twin gestations.

  14. Environmental Control and Life Support Systems for Mars Exploration: Issues and Concerns for Planetary Protection and the Protection of Science

    Science.gov (United States)

    Barta, Daniel J.; Lange, Kevin; Anderson, Molly; Vonau, Walter

    2016-07-01

    Planetary protection represents an additional set of requirements that generally have not been considered by developers of technologies for Environmental Control and Life Support Systems (ECLSS). Forward contamination concerns will affect release of gases and discharge of liquids and solids, including what may be left behind after planetary vehicles are abandoned upon return to Earth. A crew of four using a state of the art ECLSS could generate as much as 4.3 metric tons of gaseous, liquid and solid wastes and trash during a 500-day surface stay. These may present issues and concerns for both planetary protection and planetary science. Certainly, further closure of ECLSS systems will be of benefit by greater reuse of consumable products and reduced generation of waste products. It can be presumed that planetary protection will affect technology development by constraining how technologies can operate: limiting or prohibiting certain kinds of operations or processes (e.g. venting); necessitating that other kinds of operations be performed (e.g. sterilization; filtration of vent lines); prohibiting what can be brought on a mission (e.g. extremophiles); creating needs for new capabilities/ technologies (e.g. containment). Although any planned venting could include filtration to eliminate micro-organisms from inadvertently exiting the spacecraft, it may be impossible to eliminate or filter habitat structural leakage. Filtration will add pressure drops impacting size of lines and ducts, affect fan size and energy requirements, and add consumable mass. Technologies that may be employed to remove biomarkers and microbial contamination from liquid and solid wastes prior to storage or release may include mineralization technologies such as incineration, super critical wet oxidation and pyrolysis. These technologies, however, come with significant penalties for mass, power and consumables. This paper will estimate the nature and amounts of materials generated during Mars

  15. Atomistic observation of a crack tip approaching coherent twin boundaries.

    Science.gov (United States)

    Liu, L; Wang, J; Gong, S K; Mao, S X

    2014-03-18

    Coherent twin boundaries (CTBs) in nano-twinned materials could improve crack resistance. However, the role of the CTBs during crack penetration has never been explored at atomic scale. Our in situ observation on nano-twinned Ag under a high resolution transmission electron microscope (HRTEM) reveals the dynamic processes of a crack penetration across the CTBs, which involve alternated crack tip blunting, crack deflection, twinning/detwinning and slip transmission across the CTBs. The alternated blunting processes are related to the emission of different types of dislocations at the crack tip and vary with the distance of the crack tip from the CTBs.

  16. Vibration and Acoustic Testing for Mars Micromission Spacecraft

    Science.gov (United States)

    Kern, Dennis L.; Scharton, Terry D.

    1999-01-01

    The objective of the Mars Micromission program being managed by the Jet Propulsion Laboratory (JPL) for NASA is to develop a common spacecraft that can carry telecommunications equipment and a variety of science payloads for exploration of Mars. The spacecraft will be capable of carrying robot landers and rovers, cameras, probes, balloons, gliders or aircraft, and telecommunications equipment to Mars at much lower cost than recent NASA Mars missions. The lightweight spacecraft (about 220 Kg mass) will be launched in a cooperative venture with CNES as a TWIN auxiliary payload on the Ariane 5 launch vehicle. Two or more Mars Micromission launches are planned for each Mars launch opportunity, which occur every 26 months. The Mars launch window for the first mission is November 1, 2002 through April 2003, which is planned to be a Mars airplane technology demonstration mission to coincide with the 100 year anniversary of the Kittyhawk flight. Several subsequent launches will create a telecommunications network orbiting Mars, which will provide for continuous communication with lenders and rovers on the Martian surface. Dedicated science payload flights to Mars are slated to start in 2005. This new cheaper and faster approach to Mars exploration calls for innovative approaches to the qualification of the Mars Micromission spacecraft for the Ariane 5 launch vibration and acoustic environments. JPL has in recent years implemented new approaches to spacecraft testing that may be effectively applied to the Mars Micromission. These include 1) force limited vibration testing, 2) combined loads, vibration and modal testing, and 3) direct acoustic testing. JPL has performed nearly 200 force limited vibration tests in the past 9 years; several of the tests were on spacecraft and large instruments, including the Cassini and Deep Space One spacecraft. Force limiting, which measures and limits the spacecraft base reaction force using triaxial force gages sandwiched between the

  17. Motor Disorder and Anxious and Depressive Symptomatology: A Monozygotic Co-Twin Control Approach

    Science.gov (United States)

    Pearsall-Jones, Jillian G.; Piek, Jan P.; Rigoli, Daniela; Martin, Neilson C.; Levy, Florence

    2011-01-01

    The aim of this study was to investigate the relationship between poor motor ability and anxious and depressive symptomatology in child and adolescent monozygotic twins. The co-twin control design was used to explore these mental health issues in MZ twins concordant and discordant for a motor disorder, and controls. This methodology offers the…

  18. Motor Disorder and Anxious and Depressive Symptomatology: A Monozygotic Co-Twin Control Approach

    Science.gov (United States)

    Pearsall-Jones, Jillian G.; Piek, Jan P.; Rigoli, Daniela; Martin, Neilson C.; Levy, Florence

    2011-01-01

    The aim of this study was to investigate the relationship between poor motor ability and anxious and depressive symptomatology in child and adolescent monozygotic twins. The co-twin control design was used to explore these mental health issues in MZ twins concordant and discordant for a motor disorder, and controls. This methodology offers the…

  19. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak Syst

  20. The Danish Twin Registry

    DEFF Research Database (Denmark)

    Skytthe, Axel; Ohm Kyvik, Kirsten; Vilstrup Holm, Niels

    2011-01-01

    Introduction: The Danish Twin Registry is a unique source for studies of genetic, familial and environmental factors on life events, health conditions and diseases. Content: More than 85,000 twin pairs born 1870-2008 in Denmark. Validity and coverage: Four main ascertainment methods have been emp...

  1. Twin anemia polycythemia sequence

    NARCIS (Netherlands)

    Slaghekke, Femke

    2014-01-01

    In this thesis we describe that Twin Anemia Polycythemia Sequence (TAPS) is a form of chronic feto-fetal transfusion in monochorionic (identical) twins based on a small amount of blood transfusion through very small anastomoses. For the antenatal diagnosis of TAPS, Middle Cerebral Artery – Peak

  2. Results of the First Astronaut-Rover (ASRO) Field Experiment: Lessons and Directions for the Human Exploration of Mars

    Science.gov (United States)

    Cabrol, N. A.; Kosmo, J. J.; Trevino, R. C.; Thomas, H.; Eppler, D.; Bualat, M. G.; Baker, K.; Huber, E.; Sierhuis, M.; Grin, E. A.

    1999-01-01

    The first Astronaut-Rover Interaction field experiment (hereafter designated as the ASRO project) took place Feb. 22-27, 1999, in Silver Lake, Mojave Desert, CA. The ASRO project is the result of a joint project between NASA Ames Research Center and Johnson Space Center. In the perspective of the Human Exploration and Development of Space (HEDS) of the Solar System, this interaction - the astronaut and the rover as a complementary and interactive team - in the field is critical to assess but had never been tested before the Silver Lake experiment. Additional information is contained in the original extended abstract.

  3. Mars' core and magnetism.

    Science.gov (United States)

    Stevenson, D J

    2001-07-12

    The detection of strongly magnetized ancient crust on Mars is one of the most surprising outcomes of recent Mars exploration, and provides important insight about the history and nature of the martian core. The iron-rich core probably formed during the hot accretion of Mars approximately 4.5 billion years ago and subsequently cooled at a rate dictated by the overlying mantle. A core dynamo operated much like Earth's current dynamo, but was probably limited in duration to several hundred million years. The early demise of the dynamo could have arisen through a change in the cooling rate of the mantle, or even a switch in convective style that led to mantle heating. Presently, Mars probably has a liquid, conductive outer core and might have a solid inner core like Earth.

  4. Neonatal status of twins

    Directory of Open Access Journals (Sweden)

    Božinović Dragica

    2012-01-01

    Full Text Available Multiple pregnancy is a pregnancy where more than one fetus develops simultaneously in the womb, as a result of the ovulation and fertilization of more than one egg. It is relatively rare in humans and represents the rest of the phylogenetic stages. The most common are twins and they indicate the development of two fetuses in the womb. The frequency of twin pregnancies is about 1%. Multiple pregnancies belong to a group of high-risk pregnancies because of the many complications that occur during the pregnancy: higher number of premature deliveries, bleeding, early neonatal complications and higher perinatal morbidity and mortality. Such pregnancies and infants require greater supervision and monitoring. The aim of this study was to determine the percentage of baby twins born at the maternity ward of the General Hospital in Prokuplje and their morbidity and mortality. Data on the total number of deliveries, number of twins, parity and maternal age, gestational age, body weight of twins, method of delivery, Apgar score and perinatal mortality were collected and statistically analyzed by means of retrospective analysis of operative birth and neonatal protocol for 6 years (2005 of 2010. Out of 4527 mothers who gave birth 43 were pairs of twins, or 0.95% of women gave birth to twins. These babies are more likely born by Caesarean section, but delivered with slightly lower birth weight.

  5. The Cyborg Astrobiologist: Testing a Novelty-Detection Algorithm on Two Mobile Exploration Systems at Rivas Vaciamadrid in Spain and at the Mars Desert Research Station in Utah

    CERN Document Server

    McGuire, P C; Wendt, L; Bonnici, A; Souza-Egipsy, V; Ormo, J; Diaz-Martinez, E; Foing, B H; Bose, R; Walter, S; Oesker, M; Ontrup, J; Haschke, R; Ritter, H

    2009-01-01

    (ABRIDGED)In previous work, two platforms have been developed for testing computer-vision algorithms for robotic planetary exploration (McGuire et al. 2004b,2005; Bartolo et al. 2007). The wearable-computer platform has been tested at geological and astrobiological field sites in Spain (Rivas Vaciamadrid and Riba de Santiuste), and the phone-camera has been tested at a geological field site in Malta. In this work, we (i) apply a Hopfield neural-network algorithm for novelty detection based upon color, (ii) integrate a field-capable digital microscope on the wearable computer platform, (iii) test this novelty detection with the digital microscope at Rivas Vaciamadrid, (iv) develop a Bluetooth communication mode for the phone-camera platform, in order to allow access to a mobile processing computer at the field sites, and (v) test the novelty detection on the Bluetooth-enabled phone-camera connected to a netbook computer at the Mars Desert Research Station in Utah. This systems engineering and field testing hav...

  6. Magnetic exploration of a low-temperature ultramafic-hosted hydrothermal site (Lost City, 30°N, MAR)

    Science.gov (United States)

    Szitkar, Florent; Tivey, Maurice A.; Kelley, Deborah S.; Karson, Jeffrey A.; Früh-Green, Gretchen L.; Denny, Alden R.

    2017-03-01

    A 2003 high-resolution magnetic survey conducted by the Autonomous Underwater Vehicle ABE over the low-temperature, ultramafic-hosted hydrothermal field Lost City reveals a weak positive magnetic anomaly. This observation is in direct contrast to recent observations of strong positive magnetic anomalies documented over the high-temperature ultramafic-hosted hydrothermal vents fields Rainbow and Ashadze, which indicates that temperature may control the production of magnetization at these sites. The Lost City survey provides a unique opportunity to study a field that is, to date, one of a kind, and is an end member of ultramafic-hosted hydrothermal systems. Our results highlight the key contribution of temperature on magnetite production resulting from serpentinization reactions. Whereas high temperature promotes significant production and partitioning of iron into magnetite, low temperature favors iron partitioning into various alteration phases, resulting in a magnetite-poor rock. Moreover, the distribution of magnetic anomalies confirms results of a previous geological survey indicating the progressive migration of hydrothermal activity upslope. These discoveries contribute to the results of 25 yrs of magnetic exploration of a wide range of hydrothermal sites, from low- to high-temperature and from basalt- to ultramafic-hosted, and thereby validate using high-resolution magnetics as a crucial parameter for locating and characterizing hydrothermal sites hosting unique chemosynthetic-based ecosystems and potentially mineral-rich deposits.

  7. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2016-01-01

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  8. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2017-01-01

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  9. SUSY Meets Her Twin

    CERN Document Server

    Katz, Andrey; Pokorski, Stefan; Redigolo, Diego; Ziegler, Robert

    2017-01-31

    We investigate the general structure of mirror symmetry breaking in the Twin Higgs scenario. We show, using the IR effective theory, that a significant gain in fine tuning can be achieved if the symmetry is broken hardly. We emphasize that weakly coupled UV completions can naturally accommodate this scenario. We analyze SUSY UV completions and present a simple Twin SUSY model with a tuning of around 10% and colored superpartners as heavy as 2 TeV. The collider signatures of general Twin SUSY models are discussed with a focus on the extended Higgs sectors.

  10. Searching for traces of life in subglacial Lake Vostok (Antarctica) in terms of forward contamination: the lessons for exploration of icy environments on Mars

    Science.gov (United States)

    Bulat, S. A.; Alekhina, I. A.; Lipenkov, V. Ya.; Petit, J.-R.

    Bacterial 16S ribosomal gene analysis guarded by criteria for trace DNA analysis and Ancient DNA research clearly testifies for the very low biomass in accretion ice from giant subglacial Lake Vostok buried beneath 4-km thick East Antarctic ice sheet. It seems that the accretion ice is essentially germ-free indicating that the water body should also be hosting a highly sparse life, if any, unless the lake water lost its biological contents during accretion process. Due to this the search for life in Lake Vostok is constrained by a high chance of contamination similar to forward-contamination upon searching for life on Mars and other icy planets. Of 16 bacterial phylotypes initially recovered from the accretion ice the only one was kept with confident relevance to the lake environment while 15 others were presumed to be contaminants on the basis of indexing contaminant criteria developed for Lake Vostok and similar icy environments. The current way to avoid contamination appears to use stringent ice chemistry-based decontamination procedures and comprehensive biological controls including establishment of contemporary contaminant database as a prerequisite to identify and categorize sources of contaminants. More challenge would be to advance cleanliness and sterilization approaches and procedures in order to achieve and measure the level of cleanliness appropriate for tools exploring environments like Lake Vostok. As a guide for searching for life in (sub)glacial environments on Earth or Mars and Jovian's Europa our recommendations can be summarized as follows: (i) apply stringent ice decontamination procedures to meet chemistry and trace DNA analysis standards, (ii) document biological contents of various environments including humans in contact with ice samples (development of contaminant database), (iii) ensure in using relevant methods to cover both known and expected biodiversity and (iv) verify microbial findings through their possible metabolic profiles

  11. Men are from Mars, women are from Venus: Exploring gender differences in personality in the South African context

    Directory of Open Access Journals (Sweden)

    Sumaya Laher

    2013-01-01

    Full Text Available Orientation: Gender differences in personality have been explored in American and European contexts, but African and specifically South African research in the area is lacking.Research purpose: This study investigated whether there were gender differences in personality and what this might mean for a South African organisational context where personality assessments are frequently employed for decision-making.Motivation: Personality  tests  are  widely  used  in  many  fields,  including  the  industrial, organisational and research fields. Due to the impact that these tests have, it is essential that these tests are used in a fair and unbiased manner.Research design, approach and method: A cross-sectional, non-experimental design was used. A questionnaire consisting of demographic information and the NEO-PI-R was administered to a non-probability, convenience sample of 425 South African university students. The data was examined using ANOVAs and ANCOVAs.Main findings: Significant gender differences were found on Neuroticism, Anxiety, Vulnerability, Depression, Self-consciousness, Extraversion, Warmth, Activity, Assertiveness, Positive emotions, Aesthetics, Feelings, Ideas, Agreeableness, Compliance, Tender-mindedness, Altruism, Modesty, Straightforwardness, Trust, Conscientiousness, Order, Achievement striving and Self-discipline. Practical/managerial implications: The findings indicate differences between men and women are systematic and largely innate and therefore need to be acknowledged when personality tests are used in decision-making. Personality tests also need to be employed constructively to further team-building and diversity.Contribution/value-add: This study adds to the body of research in South Africa on gender as well as on how the NEO personality scales manifest in different race groups.

  12. Conjoined twins: scientific cinema and Pavlovian physiology.

    Science.gov (United States)

    Krementsov, Nikolai

    2015-01-01

    Through the lens of a 1957 documentary film, "Neural and humoral factors in the regulation of bodily functions (research on conjoined twins)," produced by the USSR Academy of Medical Sciences, this essay traces the entwined histories of Soviet physiology, studies of conjoined twins and scientific cinema. It examines the role of Ivan Pavlov and his students, including Leonid Voskresenkii, Dmitrii Fursikov and Petr Anokhin, in the development of "scientific film" as a particular cinematographic genre in Soviet Russia and explores numerous puzzles hidden behind the film's striking visuals. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  13. Twin-twin Transfusion Syndrome with a Single Ectopic Kidney in a Twin Donor. Case Presentation

    Directory of Open Access Journals (Sweden)

    Gerardo Rogelio Robaina Castellanos

    2016-10-01

    Full Text Available Twin-twin Transfusion Syndrome presents more frequently in diamniotic monochromic twins. In advanced stages and without prenatal intervention, is associated to high rates of peri natal mortality and neurological sequel in the survivors. It is presented a case of a pair of twins with severe depression at birth in which it was diagnosed a Twin-twin Transfusion Syndrome, later confirmed with the presence of anemia in the donor twin and polycythemia in the receptor twin. Both twins had an unfavourable evolution with an early neonatal death. Necropsy findings were comparable with secondary damage to the syndrome, with the particularity that both had evidences of pulmonary infection and a renal malformation in the donor twin which is not included in the proper malformations of this syndrome. The objective of this work is to point out the essential elements for the diagnosis and antenatal treatment for this disease through the peculiarities of the presented case.

  14. Fullerton Virtual Twin Study.

    Science.gov (United States)

    Segal, Nancy L

    2006-12-01

    Virtual twins (VTs; same-age unrelated siblings reared together from early infancy) have been studied at California State University (CSU), Fullerton since 1991. The current sample includes over 130 pairs. Past and current research have research have focused on siblings' similarities and differences in general intelligence and body size. Future research in these areas will continue as new pairs continue to be identified. These studies will be supplemented by analyses of personality, social relations and adjustment using monozygotic (MZ) twins, dizygotic (DZ) twins, full siblings and friends, as well as new VTs, who have participated in Twins, Adoptees, Peers and Siblings (TAPS), a collaborative project conducted between CSU Fullerton and the University of San Francisco, from 2002 to 2006.

  15. Craniofacial anomalies in twins.

    Science.gov (United States)

    Keusch, C F; Mulliken, J B; Kaplan, L C

    1991-01-01

    Studies of twins provide insight into the relative contribution of genetic and environmental factors in the causality of structural anomalies. Thirty-five affected twin pairs were identified from a group of 1114 patients with congenital craniofacial deformities evaluated from 1972 to 1989. Forty-three of these 70 twins exhibited one or more craniofacial anomalies; these were analyzed for dysmorphic characteristics, zygosity, concordance, and family history. The anomalies were categorized into two groups: malformations and deformations. The malformations (n = 36) included hemifacial microsomia (n = 10), cleft lip and palate (n = 8), cleft palate (n = 4), rare facial cleft (n = 2), craniosynostosis (n = 2), Binder syndrome (n = 2), Treacher Collins syndrome (n = 2), craniopagus (n = 2), CHARGE association (n = 1), frontonasal dysplasia (n = 2), and constricted ears (n = 1). The deformations (n = 7) included plagiocephaly (n = 5), hemifacial hypoplasia (n = 1), and micrognathia (n = 1). Twenty-one monozygotic and 14 dizygotic twin pairs were identified. The concordance rate was 33 percent for monozygotic twins and 7 percent for dizygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Mars bevares

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Hendricks, Elbert

    2009-01-01

    2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen......2009 er femåret for Mission Mars. I den anledning opridser de to kronikører, far og søn, hvorfor man bør lade planer om en bemandet tur til Mars forblive i skrivebordsskuffen...

  17. Twin delivery: how should the second twin be delivered?

    Science.gov (United States)

    Olofsson, P; Rydhström, H

    1985-11-01

    In a series of 803 pairs of twins born between 1973 and 1982, 0.33% of second twins were delivered by cesarean section after vaginal delivery of the first twin. During the last year the frequency has increased to 7%, calling attention to the problem of declining obstetric skills and experience. This has caused us to update the routines of intrapartum management of twin gestations. In the present program only commonly available obstetric techniques are used. The potentially hazardous twin delivery is excluded from a trial of vaginal delivery. Hopefully, the program will help other obstetricians to decide in favor of vaginal delivery in selected twin gestations.

  18. The ballistic Mars hopper: An alternative Mars mobility concept

    OpenAIRE

    1987-01-01

    The ballistic Mars hopper is proposed as an alternative mobility concept for unmanned exploration of the martian surface. In the ballistic Mars hopper concept, oxygen and carbon monoxide produced from the martian atmosphere are used as propellants in a rocket propulsion system for an unmanned vehicle on suborbital trajectories between landing sights separated by distances of up to 1000 km. This mobility concept is seen as uniquely capable of allowing both intensive and extensive exploration o...

  19. Nature and origin of the hematite-bearing plains of Terra Meridiani based on analyses of orbital and Mars Exploration rover data sets

    Science.gov (United States)

    Arvidson, R. E.; Poulet, F.; Morris, R.V.; Bibring, J.-P.; Bell, J.F.; Squyres, S. W.; Christensen, P.R.; Bellucci, G.; Gondet, B.; Ehlmann, B.L.; Farrand, W. H.; Fergason, R.L.; Golombeck, M.; Griffes, J.L.; Grotzinger, J.; Guinness, E.A.; Herkenhoff, K. E.; Johnson, J. R.; Klingelhofer, G.; Langevin, Y.; Ming, D.; Seelos, K.; Sullivan, R.J.; Ward, J.G.; Wiseman, S.M.; Wolff, M.J.

    2006-01-01

    The ???5 km of traverses and observations completed by the Opportunity rover from Endurance crater to the Fruitbasket outcrop show that the Meridiani plains consist of sulfate-rich sedimentary rocks that are largely covered by poorly-sorted basaltic aeolian sands and a lag of granule-sized hematitic concretions. Orbital reflectance spectra obtained by Mars Express OMEGA over this region are dominated by pyroxene, plagioclase feldspar, crystalline hematite (i.e., concretions), and nano-phase iron oxide dust signatures, consistent with Pancam and Mini-TES observations. Mo??ssbauer Spectrometer observations indicate more olivine than observed with the other instruments, consistent with preferential optical obscuration of olivine features in mixtures with pyroxene and dust. Orbital data covering bright plains located several kilometers to the south of the landing site expose a smaller areal abundance of hematite, more dust, and a larger areal extent of outcrop compared to plains proximal to the landing site. Low-albedo, low-thermal-inertia, windswept plains located several hundred kilometers to the south of the landing site are predicted from OMEGA data to have more hematite and fine-grained olivine grains exposed as compared to the landing site. Low calcium pyroxene dominates spectral signatures from the cratered highlands to the south of Opportunity. A regional-scale model is presented for the formation of the plains explored by Opportunity, based on a rising ground water table late in the Noachian Era that trapped and altered local materials and aeolian basaltic sands. Cessation of this aqueous process led to dominance of aeolian processes and formation of the current configuration of the plains. Copyright 2006 by the American Geophysical Union.

  20. The Cyborg Astrobiologist: testing a novelty detection algorithm on two mobile exploration systems at Rivas Vaciamadrid in Spain and at the Mars Desert Research Station in Utah

    Science.gov (United States)

    McGuire, P. C.; Gross, C.; Wendt, L.; Bonnici, A.; Souza-Egipsy, V.; Ormö, J.; Díaz-Martínez, E.; Foing, B. H.; Bose, R.; Walter, S.; Oesker, M.; Ontrup, J.; Haschke, R.; Ritter, H.

    2010-01-01

    In previous work, a platform was developed for testing computer-vision algorithms for robotic planetary exploration. This platform consisted of a digital video camera connected to a wearable computer for real-time processing of images at geological and astrobiological field sites. The real-time processing included image segmentation and the generation of interest points based upon uncommonness in the segmentation maps. Also in previous work, this platform for testing computer-vision algorithms has been ported to a more ergonomic alternative platform, consisting of a phone camera connected via the Global System for Mobile Communications (GSM) network to a remote-server computer. The wearable-computer platform has been tested at geological and astrobiological field sites in Spain (Rivas Vaciamadrid and Riba de Santiuste), and the phone camera has been tested at a geological field site in Malta. In this work, we (i) apply a Hopfield neural-network algorithm for novelty detection based upon colour, (ii) integrate a field-capable digital microscope on the wearable computer platform, (iii) test this novelty detection with the digital microscope at Rivas Vaciamadrid, (iv) develop a Bluetooth communication mode for the phone-camera platform, in order to allow access to a mobile processing computer at the field sites, and (v) test the novelty detection on the Bluetooth-enabled phone camera connected to a netbook computer at the Mars Desert Research Station in Utah. This systems engineering and field testing have together allowed us to develop a real-time computer-vision system that is capable, for example, of identifying lichens as novel within a series of images acquired in semi-arid desert environments. We acquired sequences of images of geologic outcrops in Utah and Spain consisting of various rock types and colours to test this algorithm. The algorithm robustly recognized previously observed units by their colour, while requiring only a single image or a few images to

  1. The effects of weathering on the strength and chemistry of Columbia River Basalts and their implications for Mars Exploration Rover Rock Abrasion Tool (RAT) results

    Science.gov (United States)

    Thomson, B. J.; Hurowitz, J. A.; Baker, L. L.; Bridges, N. T.; Lennon, A. M.; Paulsen, G.; Zacny, K.

    2014-08-01

    Basalt physical properties such as compressive strength and density are directly linked to their chemistry and constitution; as weathering progresses, basalts gradually become weaker and transition from intact rock to saprolite and ultimately, to soil. Here we quantify the degree of weathering experienced by the Adirondack-class basalts at the Mars Exploration Rover Spirit site by performing comparative analyses on the strength and chemistry of a series of progressively weathered Columbia River Basalt (CRB) from western Idaho and eastern Washington. CRB samples were subjected to compressive strength tests, Rock Abrasion Tool grinds, neutron activation analysis, and inductively coupled plasma optical emission spectroscopy. Analyses of terrestrial basalts indicate linked strength-chemical changes, as expected. Weathering sufficient to induce the loss of more than 50% of some cations (including >50% of MgO and MnO as well as ∼38% of Fe2O3 and 34% of CaO) was observed to weaken these samples by as much as 50% of their original strength. In comparison with the terrestrial samples, Adirondack-class basalts are most similar to the weakest basalt samples measured in terms of compressive strength, yet they do not exhibit a commensurate amount of chemical alteration. Since fluvial and lacustrine activity in Gusev crater appears to have been limited after the emplacement of flood basalt lavas, the observed weakness is likely attributable to thin-film weathering on exposed, displaced rocks in the Gusev plains (in addition to some likely shock effects). The results indicate that Adirondack-class basalts may possess a several mm-thick weak outer rind encasing an interior that is more pristine than otherwise indicated, and also suggest that long rock residence times may be the norm.

  2. Disease-Concordant Twins Empower Genetic Association Studies

    DEFF Research Database (Denmark)

    Tan, Qihua; Li, Weilong; Vandin, Fabio

    2017-01-01

    Genome-wide association studies with moderate sample sizes are underpowered, especially when testing SNP alleles with low allele counts, a situation that may lead to high frequency of false-positive results and lack of replication in independent studies. Related individuals, such as twin pairs...... concordant for a disease, should confer increased power in genetic association analysis because of their genetic relatedness. We conducted a computer simulation study to explore the power advantage of the disease-concordant twin design, which uses singletons from disease-concordant twin pairs as cases...... and ordinary healthy samples as controls. We examined the power gain of the twin-based design for various scenarios (i.e., cases from monozygotic and dizygotic twin pairs concordant for a disease) and compared the power with the ordinary case-control design with cases collected from the unrelated patient...

  3. Establishing a Twin Registry in Guinea-Bissau

    DEFF Research Database (Denmark)

    Bjerregaard-Andersen, Morten; Gomes, Margarida A; Joaquím, Luis C

    2013-01-01

    Twins traditionally retain a special status in many African societies. In Guinea-Bissau, twins are often well regarded yet still suffer from a very high mortality, especially in the perinatal and infant period. At the Bandim Health Project, a health and demographic surveillance site, we have...... recently established one of the first twin registries in Sub-Saharan Africa. Our short-term aim is to describe twin mortality and morbidity in order to design appropriate health interventions. Our long-term goal is a large-scale database to explore the pathogenesis of prevalent diseases; for example......, diabetes mellitus, metabolic syndrome, and infectious diseases such as HIV, tuberculosis, and malaria. A major focus area is also the etiology of low birth weight and how epigenetic processes might modulate the consequences of low birth weight in Sub-Saharan Africa. For this, monozygotic twin studies...

  4. The effect of losing the twin and losing the partner on mortality

    DEFF Research Database (Denmark)

    Tomassini, Cecilia; Rosina, Alessandro; Billari, Francesco C

    2002-01-01

    Several studies have explored the impact of marital bereavement on mortality, while increasing emphasis has recently been placed on genetic factors influencing longevity - in this paper, we study the impact of losing the spouse and losing the co-twin, for twins aged 50 to 70. We use data from...... is similar for men and women, and it is higher for monozygotic twins. The latter confirms the influence of genetic factors on survival, while the mortality trajectory with a peak in the second year after the death of the co-twin is consistent with the existence of a twin bereavement effect....

  5. Approach to Mars Field Geology

    Science.gov (United States)

    Muehlberger, William; Rice, James W.; Parker, Timothy; Lipps, Jere H.; Hoffman, Paul; Burchfiel, Clark; Brasier, Martin

    1998-01-01

    The goals of field study on Mars are nothing less than to understand the processes and history of the planet at whatever level of detail is necessary. A manned mission gives us an unprecedented opportunity to use the immense power of the human mind to comprehend Mars in extraordinary detail. To take advantage of this opportunity, it is important to examine how we should approach the field study of Mars. In this effort, we are guided by over 200 years of field exploration experience on Earth as well as six manned missions exploring the Moon.

  6. Paternal age and twinning in the Jerusalem Perinatal Study

    Science.gov (United States)

    Kleinhaus, Karine; Perrin, Mary C.; Manor, O; Friedlander, Yehiel; Calderon-Margalit, Ronit; Harlap, Susan; Malaspina, Dolores

    2008-01-01

    Objective To investigate whether incidence of twin deliveries is related to father's age, independently of mother's age, and whether it differs for same-sex or opposite-sex twin sets. Study Design In a program of research on effects of paternal age, this study used data from a prospective cohort of 92,408 offspring born in Jerusalem from 1964-1976. Of the 91,253 deliveries in the Jerusalem Perinatal Study, 1,115 were twin deliveries. The data were analyzed with General Estimate Equations to inform unconditional logistic regression. Results After controlling for maternal age, Odds Ratios (OR) and 95% Confidence Intervals (95% CI) associated with father's ages 25-34 and 35+ were 1.3 (1.1, 1.7) and 1.5 (1.2, 2.1) respectively, compared with fathers <25 years old. The effect of maternal age was partly explained by paternal age. The ORs for opposite-sex twin sets and male-male twin sets increased slightly with paternal age, while the OR for same-sex and female-female twin decreased. Conclusion Studies of twins are used to estimate effects of genes and environment in a variety of diseases. Our findings highlight the need to consider paternal as well as maternal age when analyzing data on twins to explore etiology of diseases. PMID:18771839

  7. The bioethics of separating conjoined twins in plastic surgery.

    Science.gov (United States)

    Lee, Michelle; Gosain, Arun K; Becker, Devra

    2011-10-01

    The incidence of craniopagus twins approximates four to six per 10 million births. Although rare, surgical separation of conjoined twins poses significant technical and ethical challenges. The present report uses the case of craniopagus twins AD and TD to examine the bioethical issues faced by a multidisciplinary medical team in planning the separation of craniopagus twins. AD and TD are craniopagus twins conjoined at the head. TD's head is conjoined to the back of AD's head. Neurologically, AD has the dominant cerebral circulation. TD has two normal kidneys, whereas AD has none. AD depends on TD's renal function and, on separation, will require either a kidney transplant or lifelong dialysis. This case report reviews one approach to analyzing and solving complex ethical dilemmas in pediatric plastic surgery. The principles reviewed are (1) autonomy and informed consent, focusing especially on the role of children in the informed consent process; (2) beneficence and nonmaleficence, two intricately intertwined principles because separation could potentially cause irreversible harm to one twin while improving the quality of life for the other (as separation is not a life-saving procedure, is it ethical to perform a procedure with unknown surgical risk to improve children's quality of life?); and (3) justice (is it fair to allocate excessive medical resources for the twins' separation?). The present report explores the ethics behind such decisions with respect to the separation of conjoined twins.

  8. Enhanced Engineering Cameras (EECAMs) for the Mars 2020 Rover

    Science.gov (United States)

    Maki, J. N.; McKinney, C. M.; Sellar, R. G.; Copley-Woods, D. S.; Gruel, D. C.; Nuding, D. L.; Valvo, M.; Goodsall, T.; McGuire, J.; Litwin, T. E.

    2016-10-01

    The Mars 2020 Rover will be equipped with a next-generation engineering camera imaging system that represents an upgrade over the previous Mars rover engineering cameras flown on the Mars Exploration Rover (MER) mission and the Mars Science Laboratory (MSL) rover mission.

  9. The Texas Twin Project.

    Science.gov (United States)

    Harden, K Paige; Tucker-Drob, Elliot M; Tackett, Jennifer L

    2013-02-01

    Socioeconomic position, racial/ethnic minority status, and other characteristics of the macro-environment may be important moderators of genetic influence on a wide array of psychosocial outcomes. Designed to maximize representation of low socioeconomic status families and racial/ethnic minorities, the Texas Twin Project is an ongoing study of school-age twins (preschool through 12th grade) enrolled in public schools in the Austin, Texas and Houston, Texas metropolitan areas. School rosters are used to identify twin families from a target population with sizable populations of African American (18%), Hispanic/Latino (48%), and non-Hispanic White (27%) children and adolescents, over half of whom meet US guidelines for classification as economically disadvantaged. Initial efforts have focused on a large-scale, family-based survey study involving both parent and child reports of personality, psychopathology, physical health, academic interests, parent-child relationships, and aspects of the home environment. In addition, the Texas Twin Project is the basis for an in-laboratory study of adolescent decision-making, delinquency, and substance use. Future directions include geographic expansion of the sample to the entire state of Texas (with a population of over 25 million) and genotyping of participating twins.

  10. Moessbauer In Situ Studies of the Surface of Mars

    Energy Technology Data Exchange (ETDEWEB)

    Klingelhoefer, G., E-mail: klingel@mail.uni-mainz.de [Johannes Gutenberg Universitaet, Inst. Anorganische and Analytische Chemie (Germany)

    2004-11-15

    For the first time in history, a Moessbauer spectrometer was placed on the surface of another planet. Our miniaturized Moessbauer spectrometer MIMOS II is part of the instrument payload of NASA's twin Mars Exploration Rovers (MER) 'Spirit' and 'Opportunity', which in January 2004 successfully landed at the Gusev crater and the Meridiani Planum landing sites, respectively. MIMOS II determines the Fe-bearing mineralogy of Martian soils and rocks at the Rovers' respective landing sites. The main goals of this planetary twin mission are to: (1) identify hydrologic, hydrothermal, and other processes that have operated and affected materials at the landing sites; (2) identify and investigate the rocks and soils at both landing sites, as there is a possible chance that they may preserve evidence of ancient environmental conditions and possible prebiotic or biotic activities. With MIMOS II, besides other minerals the Fe silicate olivine has been identified in both soil and rocks at both landing sites. At the Meridiani site the Fe sulfate jarosite has been identified by MIMOS II which is definitive mineralogical proof of the presence of water at this site in the past.

  11. Hypoalbuminemia in Donors with Twin-Twin Transfusion Syndrome

    NARCIS (Netherlands)

    Verbeek, L.; Middeldorp, J. M.; Hulzebos, C. V.; Oepkes, D.; Walther, F. J.; Lopriore, E.

    2013-01-01

    Objective: To estimate the differences in albumin levels between donors and recipients with twin-twin transfusion syndrome (TTTS). Methods: We performed a matched case-control study including twin pairs with TTTS treated conservatively (conservative group) or with fetoscopic laser surgery (laser gro

  12. Dialysis for twins

    DEFF Research Database (Denmark)

    Gramkow, Ann-Maria; Aarup, Michael; Andersen, L. L. T.

    2014-01-01

    A 32-year-old woman with known stage-4 chronic kidney disease due to lupus nephritis presented with twin pregnancy after in vitro fertilization at a gestational age of 24 weeks + 3 days because of imminent preterm labour. Repeated ultrasound evaluations confirmed intrauterine growth restriction...... in both twins and polyhydramnios as the cause of imminent preterm labour. After initiation of haemodialysis treatment, ultrasound evaluation showed a significant decrease in amniotic fluids, and also reduction in blood urea nitrogen and in clinical complaints could be observed. At a gestational age of 28...... weeks + 4 days, delivery was performed by Caesarean section. This case study shows that effective treatment of elevated uraemic toxins significantly reduced the morbidity risks of the twins....

  13. The Danish Twin Registry

    DEFF Research Database (Denmark)

    Skytthe, Axel; Christiansen, Lene; Kyvik, Kirsten Ohm;

    2013-01-01

    decade of combining questionnaire and survey data with national demographic, social, and health registers in Statistics Denmark. Second, we describe our most recent data collection effort, which was conducted during the period 2008-2011 and included both in-person assessments of 14,000+ twins born 1931......Over the last 60 years, the resources and the research in the Danish Twin Registry (DTR) have periodically been summarized. Here, we give a short overview of the DTR and a more comprehensive description of new developments in the twenty-first century. First, we outline our experience over the last......-1969 and sampling of biological material, hereby expanding and consolidating the DTR biobank. Third, two examples of intensively studied twin cohorts are given. The new developments in the DTR in the last decade have facilitated the ongoing research and laid the groundwork for new research directions....

  14. Maternal nutrition in twin pregnancy.

    Science.gov (United States)

    Campbell, D M; MacGillivray, I; Tuttle, S

    1982-01-01

    Energy and protein intake as measured by 24-hour urinary nitrogen values are similar in twin and singleton pregnancies. The relationship between urinary nitrogen and nitrogen intake is equally significant in twin and singleton pregnancies. Dietary zinc, copper, and iron are not different in women with twins, nor are the levels of these elements in plasma. These observations are surprising in view of the extra fetal demands on the mother and the different adaptation of twin pregnancies.

  15. Mars Spark Source Prototype

    Science.gov (United States)

    Eichenberg, Dennis J.; Lindamood, Glenn R.; Weiland, Karen J.; VanderWal, Randall L.

    1999-01-01

    The Mars Spark Source Prototype (MSSP) hardware has been developed as part of a proof of concept system for the detection of trace metals such as lead, cadmium, and arsenic in Martian dusts and soils. A spark discharge produces plasma from a soil sample and detectors measure the optical emission from metals in the plasma that will allow their identification and quantification. Trace metal measurements are vital for the assessment of the potential toxicity of the Martian environment for human exploration. The current method of X-ray fluorescence can yield concentrations only of major species. Other instruments are incompatible with the volume, weight, and power constraints for a Mars mission. The instrument will be developed primarily for use in the Martian environment, but would be adaptable for terrestrial use in environmental monitoring. This paper describes the Mars Spark Source Prototype hardware, the results of the characterization tests, and future plans for hardware development.

  16. Mars Surface Environmental Issues

    Science.gov (United States)

    Charles, John

    2002-01-01

    Planetary exploration by astronauts will require extended periods of habitation on a planet's surface, under the influence of environmental factors that are different from those of Earth and the spacecraft that delivered the crew to the planet. Human exploration of Mars, a possible near-term planetary objective, can be considered a challenging scenario. Mission scenarios currently under consideration call for surface habitation periods of from 1 to 18 months on even the earliest expeditions. Methods: Environmental issues associated with Mars exploration have been investigated by NASA and the National Space Biomedical Research Institute (NSBRI) as part of the Bioastronautics Critical Path Roadmap Project (see http ://criticalpath.jsc.nasa.gov). Results: Arrival on Mars will immediately expose the crew to gravity only 38% of that at Earth's surface in possibly the first prolonged exposure to gravity other than the 1G of Earth's surface and the zero G of weightless space flight, with yet unknown effects on crew physiology. The radiation at Mars' surface is not well documented, although the planet's bulk and even its thin atmosphere may moderate the influx of galactic cosmic radiation and energetic protons from solar flares. Secondary radiation from activated components of the soil must also be considered. Ultrafine and larger respirable and nonrespirable particles in Martian dust introduced into the habitat after surface excursions may induce pulmonary inflammation exacerbated by the additive reactive and oxidizing nature of the dust. Stringent decontamination cannot eliminate mechanical and corrosive effects of the dust on pressure suits and exposed machinery. The biohazard potential of putative indigenous Martian microorganisms may be assessed by comparison with analog environments on Earth. Even in their absence, human microorganisms, if not properly controlled, can be a threat to the crew's health. Conclusions: Mars' surface offers a substantial challenge to the

  17. Relativistic twins or sextuplets?

    CERN Document Server

    Sheldon, E S

    2003-01-01

    A recent study of the relativistic twin 'paradox' by Soni in this journal affirmed that 'A simple solution of the twin paradox also shows anomalous behaviour of rigidly connected distant clocks' but entailed a pedagogic hurdle which the present treatment aims to surmount. Two scenarios are presented: the first 'flight-plan' is akin to that depicted by Soni, with constant-velocity segments, while the second portrays an alternative mission undertaken with sustained acceleration and deceleration, illustrated quantitatively for a two-way spacecraft flight from Earth to Polaris (465.9 light years distant) and back.

  18. Imaging of conjoined twins

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, Kieran [Great Ormond Street Hospital for Children, Department of Radiology, London (United Kingdom); Kiely, Edward M.; Spitz, Lewis [Great Ormond Street Hospital for Children, Department of Surgery, London (United Kingdom)

    2006-09-15

    The incidence of conjoined twins is estimated to be around 1 in 250,000 live births. There is a distinct female predominance. In this paper the imaging of conjoined twins both antenatally and postnatally is reviewed, in particular taking into consideration recent advances with multidetector CT. Accurate counselling of parents regarding the likely outcome of the pregnancy and the likelihood of successful separation is dependent on good prenatal imaging with ultrasound and MRI. Planning of postnatal surgical separation is aided by accurate preoperative imaging which, depending on the conjoined area, will encompass many imaging modalities, but often relies heavily on CT scanning. (orig.)

  19. The Twin Interdisciplinary Neuroticism Study

    NARCIS (Netherlands)

    Riese, Harriette; Rijsdijk, Fruehling V.; Snieder, Harold; Ormel, Johan

    The Twin Interdisciplinary Neuroticism Study (TWINS) is a three-wave study including >800 twin pairs from the northern part of the Netherlands. The aim of the study is to unravel why neuroticism reflects vulnerability to mental disorders. In this study, we focus on possible mechanisms underlying

  20. The MARS2013 Mars analog mission.

    Science.gov (United States)

    Groemer, Gernot; Soucek, Alexander; Frischauf, Norbert; Stumptner, Willibald; Ragonig, Christoph; Sams, Sebastian; Bartenstein, Thomas; Häuplik-Meusburger, Sandra; Petrova, Polina; Evetts, Simon; Sivenesan, Chan; Bothe, Claudia; Boyd, Andrea; Dinkelaker, Aline; Dissertori, Markus; Fasching, David; Fischer, Monika; Föger, Daniel; Foresta, Luca; Fritsch, Lukas; Fuchs, Harald; Gautsch, Christoph; Gerard, Stephan; Goetzloff, Linda; Gołebiowska, Izabella; Gorur, Paavan; Groemer, Gerhard; Groll, Petra; Haider, Christian; Haider, Olivia; Hauth, Eva; Hauth, Stefan; Hettrich, Sebastian; Jais, Wolfgang; Jones, Natalie; Taj-Eddine, Kamal; Karl, Alexander; Kauerhoff, Tilo; Khan, Muhammad Shadab; Kjeldsen, Andreas; Klauck, Jan; Losiak, Anna; Luger, Markus; Luger, Thomas; Luger, Ulrich; McArthur, Jane; Moser, Linda; Neuner, Julia; Orgel, Csilla; Ori, Gian Gabriele; Paternesi, Roberta; Peschier, Jarno; Pfeil, Isabella; Prock, Silvia; Radinger, Josef; Ramirez, Barbara; Ramo, Wissam; Rampey, Mike; Sams, Arnold; Sams, Elisabeth; Sandu, Oana; Sans, Alejandra; Sansone, Petra; Scheer, Daniela; Schildhammer, Daniel; Scornet, Quentin; Sejkora, Nina; Stadler, Andrea; Stummer, Florian; Taraba, Michael; Tlustos, Reinhard; Toferer, Ernst; Turetschek, Thomas; Winter, Egon; Zanella-Kux, Katja

    2014-05-01

    We report on the MARS2013 mission, a 4-week Mars analog field test in the northern Sahara. Nineteen experiments were conducted by a field crew in Morocco under simulated martian surface exploration conditions, supervised by a Mission Support Center in Innsbruck, Austria. A Remote Science Support team analyzed field data in near real time, providing planning input for the management of a complex system of field assets; two advanced space suit simulators, four robotic vehicles, an emergency shelter, and a stationary sensor platform in a realistic work flow were coordinated by a Flight Control Team. A dedicated flight planning group, external control centers for rover tele-operations, and a biomedical monitoring team supported the field operations. A 10 min satellite communication delay and other limitations pertinent to human planetary surface activities were introduced. The fields of research for the experiments were geology, human factors, astrobiology, robotics, tele-science, exploration, and operations research. This paper provides an overview of the geological context and environmental conditions of the test site and the mission architecture, in particular the communication infrastructure emulating the signal travel time between Earth and Mars. We report on the operational work flows and the experiments conducted, including a deployable shelter prototype for multiple-day extravehicular activities and contingency situations.

  1. Mars Pathfinder

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    First of NASA's Discovery missions. Launched in December 1996 and arrived at Mars on 4 July 1997. Mainly intended as a technology demonstration mission. Used airbags to cushion the landing on Mars. The Carl Sagan Memorial station returned images of an ancient flood plain in Ares Vallis. The 10 kg Sojourner rover used an x-ray spectrometer to study the composition of rocks and travelled about 100 ...

  2. Identical Twins Raised Apart

    Science.gov (United States)

    Farnsworth, David L.

    2015-01-01

    This article describes a bivariate data set that is interesting to students. Indeed, this particular data set, which involves twins and IQ, has sparked more student interest than any other set that I have presented. Specific uses of the data set are presented.

  3. Sleep Terrors in Twins

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2008-12-01

    Full Text Available In an attempt to clarify the genetic and environmental causes of sleep terrors in childhood, reasearchers in Canada followed 390 pairs of monozygotic and dizygotic twins by assessing the frequency of sleep terrors at 18 and 30 months of age using a questionnaire administered to the biological mothers.

  4. Twin Hub Network (poster)

    NARCIS (Netherlands)

    Kreutzberger, E.D.; Konings, J.W.

    2014-01-01

    Twin hub network, a European Interreg IVB project, aims at making intermodal rail transport within, to and from North West Europe more competitive, in particular between seaports and inland terminals. Improving rail competitiveness enables to shift freight flows from road to rail, providing a more s

  5. Amelia in Twin Pregnancy

    Directory of Open Access Journals (Sweden)

    Davari Tanha Fatemeh

    2009-04-01

    Full Text Available Limb bud first appears during the third week of gestation with the upper limb buds appearing a few days before the lower limb buds. Complete absence of one or more limbs, called Amelia, occurs prior to the eighth week of gestation. We report a case of Amelia in a twin gestation.

  6. TWIN BLOCK (Studi Pustaka

    Directory of Open Access Journals (Sweden)

    Evie Lamtiur

    2015-08-01

    Full Text Available Young patients with class II skeletal malocclusion are often found. To avoid further discrepancy of this case, myofunctional therapy is one of the options. Functional appliance often used for such treatment. Functional appliance has been modified since activator was introduced by Andresen. With its bulky shape, activator makes difficulty for patient to speak and eat. Patient unable to wear it full time due to uncomfortness and negative facial appearance. In 1977, Clark developed twin block to overcome the weakness of previous appliances. A more simple design allows patient to be more comfortable and willing to wear it longer. Twin block is myofunctional appliance to reposition the mandible forward for skeletal class II correction with retruded mandible. This paper describes the design, clinical management effects of twin block treatment and brief case presentation using twin block appliance. Similar to the study reports found, this case revealed improvement of facial appearance, decrease overjet and overbite, improvement of molar relationship and good compliance of patient.

  7. Twin-twin transfusion syndrome - diagnosis and prognosis

    Directory of Open Access Journals (Sweden)

    Hajrić-Egić Amira

    2003-01-01

    Full Text Available Twin-twin transfusion syndrome is a serious complication of monozygotic, monochorionic, diamniotic twins resulting from transplacental vascular communications. In this syndrome blood is thought to be shunted from one twin - donor,who develops anaemia,growth retardation and oligoamnios, to the other twin - recipient,who becomes plethoric,macrosomic and develops polyhydroamnios. The incidence of twin-twin transfusion syndrome ranges from 5-15% of all twin pregnancies. If this condition develops in the second trimester, it is usually associated with spontaneous abortion and death of one or both fetuses before viability. Developing the syndrome in the third trimester has better perinatal outcome. Mortality rates ranging from 56%-100%, depending on gestational age and severity of the syndrome. The ultrasound criterias for diagnosis, in this study,were the presence of twins of the same sex with discordant growth, with oligohydroamnios in one twin sac and polyhydroamnios in the other one, one placenta and thin membrane between twins. The present study shows clinical course of 14 cases and value of Doppler ultrasound to analyze the usefulness of umbilical artery blood flow velocimetry for predicting the risk of twin-twin transfusion syndrome. 14 twin pregnancies with twin-twin transfusion syndrome were diagnosed during the last four years period and prospectivelly followed. 9 cases were diagnosed before the completion od 28 weeks of gestation.The mean gestational age was 21,6_+4,2 weeks at diagnosis and 23,2+_3,6 weeks at delivery. 5 cases were diagnosed after 28 weeks of gestation. The mean gestational age in this group was 29,6+_2,1 weeks at diagnosis and 33+_3,3 weeks at delivery. The survival rate in this study was 29%(8/28.9 cases ended in spontaneous abortion between 18th and 27th weeks of pregnancy (table 1 and 5 in premature labor (table 2.There were 7 intrauterine death (5 at admission and 2 few days after admission and 13 neonatal deaths

  8. Mars Radar Opens a Planet's Third Dimension

    Science.gov (United States)

    2008-01-01

    Radar sounder instruments orbiting Mars have looked beneath the Martian surface and opened up the third dimension for planetary exploration. The technique's success is prompting scientists to think of all the other places in the Solar System where they would like to use radar sounders. The first radar sounder at Mars was the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) on the European Space Agency's Mars Express Orbiter. It has been joined by the complementary Shallow Subsurface Radar (SHARAD), operating at a different wavelength aboard NASA's Mars Reconnaissance Orbiter. The data in this animation are from SHARAD.

  9. Mitral valve regurgitation in twins

    DEFF Research Database (Denmark)

    Bakkestrøm, Rine; Larsen, Lisbeth Aagaard; Møller, Jacob Eifer

    2016-01-01

    BACKGROUND: Smaller observational studies have suggested familial clustering of mitral regurgitation (MR). Using a large twin cohort, the aims were to assess MR concordance rates and assess mortality in MR twins and unaffected cotwins. METHODS: Through the Danish Twin Registry, twins...... with an International Classification of Diseases, Eighth Revision and Tenth Revision diagnosis code of MR born 1880-1989 were identified and proband-wise concordance rates were calculated. To assess whether having a cotwin with MR affected survival, 10 matched twins without MR (n = 5,575) were selected for each MR twin...... (n = 562), and all-cause mortality rates were assessed. RESULTS: Among the 87,432 twins alive January 1, 1977, or later, 494 (0.57%) MR individuals were identified. Six MR concordant pairs were found, of which 3 were monozygotic. Proband-wise concordance rate when accounting for right censoring...

  10. Metabolomic and Genomic Markers of Atherosclerosis as Related to Oxidative Stress, Inflammation, and Vascular Function in Twin Astronauts

    Science.gov (United States)

    Lee, Stuart M. C.; Rana, Brinda K.; Stenger, Michael B.; Sears, Dorothy D.; Smith, Scott M.; Zwart, Sara R.; Macias, Brandon R.; Hargans, Alan R.; Sharma, Kumar; De Vivo, Immaculata

    2017-01-01

    BACKGROUND: Future human space travel will consist primarily of long-duration missions onboard the International Space Station (ISS) or exploration-class missions to Mars, its moons, or nearby asteroids. Astronauts participating in long-duration missions may be at an increased risk of oxidative stress and inflammatory damage due to radiation, psychological stress, altered physical activity, nutritional insufficiency, and hyperoxia during extravehicular activity. By studying one identical twin during his 1-year ISS mission and his ground-based twin, this work extends a current NASA-funded investigation to determine whether these spaceflight factors contribute to an accelerated progression of atherosclerosis. This study of twins affords a unique opportunity to examine spaceflight-related atherosclerosis risk that is independent of the confounding factors associated with different genotypes. PURPOSE: The purpose of this investigation was to determine whether biomarkers of oxidative and inflammatory stress are elevated during and after long-duration spaceflight and determine if a relation exists between levels of these biomarkers and structural and functional indices of atherosclerotic risk measured in the carotid and brachial arteries. These physiological and biochemical data will be extended by using an exploratory approach to investigate the relationship between intermediate phenotypes and risk factors for atherosclerosis and the metabolomic signature from plasma and urine samples. Since metabolites are often the indirect products of gene expression, we simultaneously assessed gene expression and DNA methylation in leukocytes. HYPOTHESIS: We predict that, compared to the ground-based twin, the space-flown twin will experience elevated biomarkers of oxidative stress and inflammatory damage, altered arterial structure and function, accelerated telomere shortening, dysregulation of genes associated with oxidative stress and inflammation, and a metabolic profile shift

  11. Brazilian Twin Registry: A Bright Future for Twin Studies/Twin Research: Twin Study of Alcohol Consumption and Mortality; Oxygen Uptake in Adolescent Twins/In the News: Superfecundated Twins In Vietnam; Adolescent Twin Relations; Twin and Triplet Co-Workers; A Special Twin Ultrasound; Monozygotic Twins With Different Skin Color; Identical Twin Returns from Space.

    Science.gov (United States)

    Segal, Nancy L

    2016-06-01

    The establishment of the Brazilian Twin Registry for the study of genetic, social, and cultural influences on behavior is one of eleven newly funded projects in the Department of Psychology at the University of São Paulo. These 11 interrelated projects form the core of the university's Center for Applied Research on Well-Being and Human Behavior. An overview of the planned twin research and activities to date is presented. Next, two recent twin studies are reviewed, one on the relationship between alcohol consumption and mortality, and the other on factors affecting maximal oxygen uptake. Twins cited in the media include the first identified superfecundated twins in Vietnam, adolescent twin relations, twins and triplets who work together, monozygotic twins with different skin tones and a co-twin control study that addresses the effects of space travel.

  12. The Maternal Emotional Climate Predicts Twin Sibling Relationship Quality.

    Science.gov (United States)

    Mark, Katharine M; Pike, Alison; Latham, Rachel M; Oliver, Bonamy R

    2017-04-01

    We investigated the association between maternal expressed emotion and twin relationship quality, after controlling for a maternal questionnaire measure of the mother-child relationship. This was explored within a community sample of 156 mothers and their two young twin children (M child age = 3.69 years; SD child age = 0.37). Mothers reported on the twin-twin relationship and the mother-child relationship via questionnaire. They were also interviewed about each child using the innovative Preschool Five Minute Speech Sample (Daley et al., 2003), which yields information about relative positive:negative maternal expressed emotion. Mothers who expressed more family-wide positive emotion and less family-wide negative emotion also reported more positivity, but not negativity, within the twin relationship - even when controlling for questionnaire reports of the mother-child relationship. Counter to expectations, discrepancies in mothers' expressed emotion between their twins also predicted more positive sibling relationships. Our findings corroborate the well established spill-over effect, whereby families are viewed as emotional units of interdependent individuals, none of whom can be understood in isolation from one another. Most importantly, the Preschool Five Minute Speech Sample provides information about mothering that questionnaire reports may not, and thus it is a useful tool in better understanding the twin family system.

  13. NASA Mars Science Laboratory Rover

    Science.gov (United States)

    Olson, Tim

    2017-01-01

    Since August 2012, the NASA Mars Science Laboratory (MSL) rover Curiosity has been operating on the Martian surface. The primary goal of the MSL mission is to assess whether Mars ever had an environment suitable for life. MSL Science Team member Dr. Tim Olson will provide an overview of the rover's capabilities and the major findings from the mission so far. He will also share some of his experiences of what it is like to operate Curiosity's science cameras and explore Mars as part of a large team of scientists and engineers.

  14. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    2009-01-01

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  15. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  16. Hydropic Placenta as a First Manifestation of Twin-Twin Transfusion in a Monochorionic Diamniotic Twin Pregnancy

    NARCIS (Netherlands)

    de Laat, Monique W. M.; Manten, Gwendoline T. R.; Nikkels, Peter G. J.; Stoutenbeek, Philip

    2009-01-01

    Monochorionic twin pregnancies are at a 10% to 1.5% risk of developing twin-twin transfusion syndrome (TTTS).(1) Monitoring such pregnancies is aimed at evaluating the fetal condition by measuring the amount of amniotic fluid, Doppler parameters, and fetal growth. Twin-twin transfusion syndrome may

  17. 5 in 1 Drill For Mars Sample Return Mission Project

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA is investigating a Mars Sample Return Mission, consisting of at least three separate missions: 1) Mars Astrobiology Explorer-Cacher, MAX-C (sample acquisition...

  18. Planets and satellites: tectonic twins

    Science.gov (United States)

    Kochemasov, G. G.

    2015-10-01

    There are only three solid planet-satellite pairs in the Solar system: Earth -Moon, Mars -Phobos, Pluto - Charon. For the first two pairs tectonic analogies were shown and explained by moving them in one circumsolar orbit. As it is known from the wave planetology [3, 4, 6], "orbits make structures". For the third pair the same was stated as a prediction based on this fundamental rule. Global tectonic forms of wave origin appear in cosmic bodies because they move in keplerian orbits with periodically changing accelerations. Warping bodies waves have a stationary character and obeying wave harmonics lengths. Starting from the fundamental 2πR-long wave 1 making the ubiquitous tectonic dichotomy (two-face appearance) warping wave lengths descend along harmonics. Very prominent along with the wave 1 are waves 2 responsible for tectonic sectoring superimposed on the wave 1 segments. Practically all bodies have traces of shorter waves making numerous polygons (rings) often confused with impact craters. Earth and the Moon moving in one circumsolar orbit both are distorted by wave 1, wave 2 and wave 4 features aligned along extent tectonic lines [4, 5]. At Earth they are: Pacific Ocean (2πR-structure) and Indian Ocean (πR-structure) from both ends with Malay Archipelago (πR/4-structure) in the middle. At Moon they are: Procellarum Ocean (2πR) and SPA Basin (πR) from ends and Mare Orientale (πR/4) in the middle. A regular disposition is surprising. Both Oceans and Basin occur on opposite hemispheres, lying in the middle both ring structures occur in the boundary between two hemispheres and are of the same relative size. These triads stretch along lines parallel to the equator (Earth) and with the angle about 30 degrees to it (Moon) indicating at a different orientation of the rotation axes in the ancient time [2]. On the whole, one could speak about a "lunar mould" of Earth [5] (Fig. 1-3). Another tectonic twin is the pair Mars -Phobos. Both bodies sharing one

  19. An advanced perspective on twin growth in Nickel-Titanium

    Science.gov (United States)

    Ezaz, Tawhid

    2011-12-01

    . Further, an outstanding issue, detwinning in NiTi, has been addressed via first principles energetics calculations of twin nucleation and growth. Shape memory behavior of NiTi alloys directly depends on the detwinning or growth of twin variants in martensite. Our results based on ion relaxation and valence charge distribution point to a distinct energy barrier during detwinning process and the mechanism is mediated by a complex conjunction of shear and shuffle. In the second part of the work, the energetics of slip-coherent twin boundary (CTB) interactions are established under tensile deformation in fcc copper with molecular dynamics simulations, exploring the entire stereographic triangle. The CTBs serve as effective barriers in some crystal orientations, more than others, consistent with experimental observations. The resulting dislocation structures upon slip-twin reactions are identified in terms of Burgers vector analysis. Visualization of the dislocation transmission; lock formation; dislocation incorporation to twin boundaries; dislocation multiplication at the matrix-twin interface; and twin translation, growth, and contraction behaviors cover the most significant reactions that can physically occur providing a deeper understanding of the mechanical behavior of fcc alloys in the presence of twin boundaries. The results show a considerable contribution of shear stresses and the residual dislocation at the twin boundaries and point to its effect in strengthening of fcc metals.

  20. A twin and molecular genetics study of sleep paralysis and associated factors.

    OpenAIRE

    Denis, Dan; French, Christopher C.; Rowe, Richard; Zavos, Helena M S; Nolan, Patrick M.; Parsons, Michael J.; Gregory, Alice M

    2015-01-01

    Sleep paralysis is a relatively common but under-researched phenomenon. In this paper we examine prevalence in a UK sample and associations with candidate risk factors. This is the first study to investigate the heritability of sleep paralysis in a twin sample and to explore genetic associations between sleep paralysis and a number of circadian expressed single nucleotide polymorphisms. Analyses are based on data from the Genesis1219 twin/sibling study, a community sample of twins/siblings fr...

  1. A twin and molecular genetics study of sleep paralysis and associated factors.

    OpenAIRE

    Denis, Dan; French, Christopher C.; Rowe, Richard; Zavos, Helena M. S.; Nolan, Patrick M.; Parsons, Michael J.; Gregory, Alice M.

    2015-01-01

    Sleep paralysis is a relatively common but under-researched phenomenon. In this paper we examine prevalence in a UK sample and associations with candidate risk factors. This is the first study to investigate the heritability of sleep paralysis in a twin sample and to explore genetic associations between sleep paralysis and a number of circadian expressed single nucleotide polymorphisms. Analyses are based on data from the Genesis1219 twin/sibling study, a community sample of twins/siblings fr...

  2. Reared-Apart Chinese Twins: Chance Discovery/Twin-Based Research: Twin Study of Media Use; Twin Relations Over the Life Span; Breast-Feeding Opposite-Sex Twins/Print and Online Media: Twins in Fashion; Second Twin Pair Born to Tennis Star; Twin Primes; Twin Pandas.

    Science.gov (United States)

    Segal, Nancy L

    2017-04-01

    A January 2017 reunion of 10-year-old reared-apart Chinese twin girls was captured live on ABC's morning talk show Good Morning America, and rebroadcast on their evening news program Nightline. The twins' similarities and differences, and their participation in ongoing research will be described. This story is followed by reviews of twin research concerning genetic and environmental influences on media use, twin relations across the lifespan and the breast-feeding of opposite-sex twins. Popular interest items include twins in fashion, the second twin pair born to an internationally renowned tennis star, twin primes and twin pandas.

  3. Disease-Concordant Twins Empower Genetic Association Studies.

    Science.gov (United States)

    Tan, Qihua; Li, Weilong; Vandin, Fabio

    2017-01-01

    Genome-wide association studies with moderate sample sizes are underpowered, especially when testing SNP alleles with low allele counts, a situation that may lead to high frequency of false-positive results and lack of replication in independent studies. Related individuals, such as twin pairs concordant for a disease, should confer increased power in genetic association analysis because of their genetic relatedness. We conducted a computer simulation study to explore the power advantage of the disease-concordant twin design, which uses singletons from disease-concordant twin pairs as cases and ordinary healthy samples as controls. We examined the power gain of the twin-based design for various scenarios (i.e., cases from monozygotic and dizygotic twin pairs concordant for a disease) and compared the power with the ordinary case-control design with cases collected from the unrelated patient population. Simulation was done by assigning various allele frequencies and allelic relative risks for different mode of genetic inheritance. In general, for achieving a power estimate of 80%, the sample sizes needed for dizygotic and monozygotic twin cases were one half and one fourth of the sample size of an ordinary case-control design, with variations depending on genetic mode. Importantly, the enriched power for dizygotic twins also applies to disease-concordant sibling pairs, which largely extends the application of the concordant twin design. Overall, our simulation revealed a high value of disease-concordant twins in genetic association studies and encourages the use of genetically related individuals for highly efficiently identifying both common and rare genetic variants underlying human complex diseases without increasing laboratory cost. © 2016 John Wiley & Sons Ltd/University College London.

  4. Minimal Mirror Twin Higgs

    CERN Document Server

    Barbieri, Riccardo; Harigaya, Keisuke

    2016-01-01

    In a Mirror Twin World with a maximally symmetric Higgs sector the little hierarchy of the Standard Model can be significantly mitigated, perhaps displacing the cutoff scale above the LHC reach. We show that consistency with observations requires that the Z2 parity exchanging the Standard Model with its mirror be broken in the Yukawa couplings. A minimal such effective field theory, with this sole Z2 breaking, can generate the Z2 breaking in the Higgs sector necessary for the Twin Higgs mechanism, and has constrained and correlated signals in invisible Higgs decays, direct Dark Matter Detection and Dark Radiation, all within reach of foreseen experiments. For dark matter, both mirror neutrons and a variety of self-interacting mirror atoms are considered. Neutrino mass signals and the effects of a possible additional Z2 breaking from the vacuum expectation values of B-L breaking fields are also discussed.

  5. Emergence of Digital Twins

    OpenAIRE

    Datta, Shoumen Palit Austin

    2016-01-01

    Multiple forms of digital transformation are imminent. Digital Twins represent one concept. It is gaining momentum because it may offer real-time transparency. Rapid diffusion of digital duplicates faces hurdles due to lack of semantic interoperability between architectures, standards and ontologies. The technologies necessary for automated discovery are in short supply. Progression of the field depends on convergence of information technology, operational technology and protocol-agnostic tel...

  6. Nutrition in twin pregnancy.

    Science.gov (United States)

    MacGillivray, I

    1979-01-01

    The urinary nitrogen output appears to be related to both protein and energy intake, so that women having heavier babies probably eat more, although this may simply mean that they are larger women. Women with twin pregnancies have been found to have a lesser urinary nitrogen output, but it seems unlikely that this be due to lower intakes. They might simply utilize their diet more efficiently--a hypothesis that is now being tested.

  7. CROSS DRIVE: A New Interactive and Immersive Approach for Exploring 3D Time-Dependent Mars Atmospheric Data in Distributed Teams

    Science.gov (United States)

    Gerndt, Andreas M.; Engelke, Wito; Giuranna, Marco; Vandaele, Ann C.; Neary, Lori; Aoki, Shohei; Kasaba, Yasumasa; Garcia, Arturo; Fernando, Terrence; Roberts, David; CROSS DRIVE Team

    2016-10-01

    Atmospheric phenomena of Mars can be highly dynamic and have daily and seasonal variations. Planetary-scale wavelike disturbances, for example, are frequently observed in Mars' polar winter atmosphere. Possible sources of the wave activity were suggested to be dynamical instabilities and quasi-stationary planetary waves, i.e. waves that arise predominantly via zonally asymmetric surface properties. For a comprehensive understanding of these phenomena, single layers of altitude have to be analyzed carefully and relations between different atmospheric quantities and interaction with the surface of Mars have to be considered. The CROSS DRIVE project tries to address the presentation of those data with a global view by means of virtual reality techniques. Complex orbiter data from spectrometer and observation data from Earth are combined with global circulation models and high-resolution terrain data and images available from Mars Express or MRO instruments. Scientists can interactively extract features from those dataset and can change visualization parameters in real-time in order to emphasize findings. Stereoscopic views allow for perception of the actual 3D behavior of Mars's atmosphere. A very important feature of the visualization system is the possibility to connect distributed workspaces together. This enables discussions between distributed working groups. The workspace can scale from virtual reality systems to expert desktop applications to web-based project portals. If multiple virtual environments are connected, the 3D position of each individual user is captured and used to depict the scientist as an avatar in the virtual world. The appearance of the avatar can also scale from simple annotations to complex avatars using tele-presence technology to reconstruct the users in 3D. Any change of the feature set (annotations, cutplanes, volume rendering, etc.) within the VR is immediately exchanged between all connected users. This allows that everybody is always

  8. Tribute to dr louis keith: twin and physician extraordinaire/twin research reports: influences on asthma severity; chimerism revisited; DNA strand break repair/media reports: twins born apart; elevated twin frequencies; celebrity father of twins; conjoined twinning.

    Science.gov (United States)

    Segal, Nancy L

    2014-10-01

    The International Society for Twin Studies has lost a valued friend and colleague. Dr Louis Keith, Emeritus Professor of Obstetrics and Gynecology at Northwestern University, in Chicago, passed away on Sunday, July 6, 2014. His life and work with twins will be acknowledged at the November 2014 International Twin Congress in Budapest, Hungary. Next, twin research reports on the severity of asthma symptoms, a case of chimerism, and factors affecting DNA breakage and repair mechanisms are reviewed. Media reports cover twins born apart, elevated twin frequencies, a celebrity father of twins, and a family's decision to keep conjoined twins together.

  9. Socioeconomic position and twins' health

    DEFF Research Database (Denmark)

    Osler, Merete; McGue, Matt; Christensen, Kaare

    2007-01-01

    of middle-aged Danish twins was conducted in 1998-99. The study population included 1266 like-sex twin pairs [52.5% monozygotic (MZ) and 47.6% dizygotic (DZ)]. Data were obtained on childhood and adult social class and on height, BMI, grip strength, depression symptoms, self-rated health, cognitive function......, prenatal and rearing environmental factors from environmental factor later in life, we compared the health status among male and female twin pairs who lived together during childhood and were discordant or concordant on adult socioeconomic position. METHODS: A cross-sectional survey among a random sample......, physical activity, smoking, alcohol and food intake. RESULTS: The expected associations between the individual twins' adult social class and health measures were observed. Among DZ male twins discordant on adult social class, the higher social class twin was on average significantly taller and had higher...

  10. Twin-to-twin delivery time: neonatal outcome of the second twin.

    Science.gov (United States)

    Schneuber, Susanne; Magnet, Eva; Haas, Josef; Giuliani, Albrecht; Freidl, Thomas; Lang, Uwe; Bjelic-Radisic, Vesna

    2011-12-01

    To examine the effect of twin-to-twin delivery time (TTDT) on neonatal outcome. We evaluated twin deliveries >34 weeks of gestation. Twin pregnancies with both twins delivered by cesarean section and pregnancies with antenatal complications were excluded. We analyzed TTDT and neonatal outcomes of the second twin (umbilical arterial pH value (pH(art)), Apgar scores at 1, 5 and 10 minutes, need for intensive care). The study population was divided into two homogenous groups based on the mode of delivery: (A) vertex presentation and vaginal delivery of both twins, (B) vertex presentation and vaginal or vaginal operative delivery of twin I, breech or transverse presentation and vaginal breech delivery or cesarean section (CS) of twin II. A total of 207 twin pairs were included in our study. In Group A (n = 151) there were no significant correlations between TTDT and pH(art) or Apgar scores at 1,5 and 10 minutes of twin II (p = .156; 0.861; 0.151 and 0.384, respectively). In Group B (n = 56), the mean pH(art) of twin II was inversely correlated to TTDT, but not significantly (p = .417). TTDT was inversely related to 1-min and 5-min Apgar scores, but not significantly (p = .330; p = .138, respectively). The 10-min Apgar score showed no correlation with TTDT (p = .638). Increasing TTDT was not associated with adverse fetal outcome. Expectant management of the second twin appears possible and elapsed time alone does not appear to be an indication for intervention.

  11. Human Mars Surface Mission Nuclear Power Considerations

    Science.gov (United States)

    Rucker, Michelle A.

    2018-01-01

    A key decision facing Mars mission designers is how to power a crewed surface field station. Unlike the solar-powered Mars Exploration Rovers (MER) that could retreat to a very low power state during a Martian dust storm, human Mars surface missions are estimated to need at least 15 kilowatts of electrical (kWe) power simply to maintain critical life support and spacecraft functions. 'Hotel' loads alone for a pressurized crew rover approach two kWe; driving requires another five kWe-well beyond what the Curiosity rover’s Radioisotope Power System (RPS) was designed to deliver. Full operation of a four-crew Mars field station is estimated at about 40 kWe. Clearly, a crewed Mars field station will require a substantial and reliable power source, beyond the scale of robotic mission experience. This paper explores the applications for both fission and RPS nuclear options for Mars.

  12. Trojan twin planets

    Science.gov (United States)

    Dvorak, R.; Loibnegger, B.; Schwarz, R.

    2017-03-01

    The Trojan asteroids are moving in the vicinity of the stable Lagrange points L_4 and L_5 of the gas giants Jupiter, Uranus and Neptune. Their motion can be described and understood with the aid of the restricted three-body problem. As an extension of this problem we investigate how stable motion close to the Lagrange points of two massive bodies can exist. This configuration can be described as the Trojan Twin Problem when we regard the two additional bodies as having a mass significantly smaller than the the two primary bodies: a star in the center (m_1) and an additional Jupiter-like mass (m_2). Using this 4-body problem we have undertaken numerical investigations concerning possible stable "twin orbits". However, these two bodies (m_3 and m_4) in Trojan-like orbits may have quite different masses. We decided to choose 6 different scenaria for this problem: as primary body, m2, we have taken a Jupiter-like planet, a Saturn-like one, and a super-Earth with 10 Earthmasses (m_{Earth}) respectively. As quasi twin planets, we have used different mass ratios namely objects for m3 and m4 from 10m_{Earth} to Moon like ones. We found different stable configurations depending on the involved masses and the initial distances between the twins (always close to the Lagrange point). Although the formation of such a configuration seems to be not very probable we should not exclude that it exists regarding the huge number of planets even in our own galaxy. This model is of special interest when the most massive planet (m_2) is moving on an orbit in the habitable zone around a main sequence star. One can use our results of stable orbits of Trojan Twin Planets (or asteroids) for extrasolar systems having as second primary a Jupiter-like, a Saturn-like or a super-Earth like planet around a star similar to our Sun.

  13. Mar Capeans

    CERN Multimedia

    2017-01-01

    Mar Capeans, CERN researcher, answers the question to "What can we do in the world of sciences and innovation to make visible the invisible?". This piece belongs to a series of videos made by the Spanish Aquae Foundation, a supporter of the CERN & Society Foundation.

  14. Mar adentro

    OpenAIRE

    Florián Guerrero, Mayra

    2014-01-01

    La bravura del mar destruyó primero las canchas de fútbol, luego se tragó casas y finalmente las playas. El otrora balneario exclusivo de Buenos Aires, donde se fundó el famoso restaurant Morillas en los años 40, es ahora un tímido recuerdo en medio del chocar incesante de las olas.

  15. Metabolomic and Genomic Markers of Atherosclerosis as Related to Oxidative Stress, Inflammation, and Vascular Function in Twin Astronauts

    Science.gov (United States)

    Lee, Stuart M. C.; Rana, Brinda K.; Stenger, Michael B.; Sears, Dorothy D.; Smith, Scott M.; Macias, Brandon R.; Hargens, Alan R.; Sharma, Kumar; De Vivo, Immaculata

    2016-01-01

    Background: Future human space travel will consist primarily of long-duration missions onboard the International Space Station (ISS) or exploration-class missions to Mars, its moons, or nearby asteroids. Astronauts participating in long-duration missions may be at an increased risk of oxidative stress and inflammatory damage due to radiation, psychological stress, altered physical activity, nutritional insufficiency, and hyperoxia during extravehicular activity. By studying one identical twin during his 1-year ISS mission and one ground-based twin, this work extends a current NASA-funded investigation to determine whether these spaceflight factors contribute to an accelerated progression of atherosclerosis. This study of twins affords a unique opportunity to examine the spaceflight-related atherosclerosis risk independent of the confounding factors associated with different genotypes. Purpose: The purpose of this investigation is to determine whether biomarkers of oxidative and inflammatory stress are elevated during and after long-duration spaceflight and determine if a relation exists between levels of these biomarkers and structural and functional indices of atherosclerotic risk measured in the carotid and brachial arteries. These physiological and biochemical data will be extended by using an exploratory approach to investigate the relationship between intermediate phenotypes and risk factors for atherosclerosis and the metabolomic signature from plasma and urine samples. Since metabolites are often the indirect products of gene expression, we will simultaneously assess gene expression and DNA methylation in leukocytes. Hypothesis: We predict that the space-flown twin will experience elevated biomarkers of oxidative stress and inflammatory damage, altered arterial structure and function, accelerated telomere shortening, dysregulation of genes associated with oxidative stress and inflammation, and a metabolic profile shift that is associated with elevated

  16. When You Are a Twin or Triplet

    Science.gov (United States)

    ... be a twin? Are you a twin and wonder why everyone thinks it's so special? It's fascinating ... the way the egg is fertilized when a woman becomes pregnant . In fraternal twins, two different eggs ...

  17. The Simud-Tiu Valles hydrologic system: A multidisciplinary study of a possible site for future Mars on-site exploration

    Science.gov (United States)

    Pajola, Maurizio; Rossato, Sandro; Baratti, Emanuele; Mangili, Clara; Mancarella, Francesca; McBride, Karen; Coradini, Marcello

    2016-04-01

    When looking for traces of past life on Mars, we have to look primarily for places where water was present, possibly for long time intervals. The Simud and Tiu Valles are two large outflow channels connected to the north with the Chryse Basin, Oxia Palus quadrangle. The area, carved by water during the Noachian/Early Hesperian is characterized by a complex geological evolution. The geomorphological analysis shows the presence of fluvial and alluvial structures, interpreted as fluvial channels and terraces, debris flow fronts and short-lasting small water flows coexisting with maar-diatremes and mud volcanoes. Several morphological features indicate a change in water flux direction after the main erosive phase. During this period water originated from the Masursky crater and flown southwards into the Hydraotes Chaos. This phenomenon caused the studied area to become a depocenter where fine-grained material deposition took place, possibly in association with ponding water. This setting is potentially quite valuable as traces of life may have been preserved. The presence of water at various times over a period of about 1 Ga in the area is corroborated by mineralogical analyses of different areas that indicate the possible presence of hydrated minerals mixtures, such as sulfate-bearing deposits. Given the uniqueness of the evolution of this region, the long term interactions between fluvial, volcanic, and tectonic processes and its extremely favorable landing parameters (elevation, slope, roughness, rock distribution, thermal inertia, albedo, etc.), we decided to propose this location as a possible landing site for the ESA ExoMars 2018, the NASA Mars 2020 and future on-site missions.

  18. Contemporary management of complicated monochorionic twins.

    Science.gov (United States)

    Moise, Karen Y; Kugler, Lisa; Jones, Tyra

    2012-01-01

    Monochorionic twins are at increased risk for unique complications including twin-twin transfusion syndrome (TTTS), selective intrauterine growth restriction (sIUGR), and twin-reversed arterial perfusion (TRAP) sequence. Twin-twin transfusion syndrome is treated with laser photocoagulation whereas selective reduction is an option in previable sIUGR or TRAP sequence. The nurse is integral in the management, education, care and support of women with complicated pregnancies. © 2012 AWHONN, the Association of Women's Health, Obstetric and Neonatal Nurses.

  19. Genetic and Environmental Effects on Stuttering: A Twin Study from Finland

    Science.gov (United States)

    Rautakoski, Pirkko; Hannus, Therese; Simberg, Susanna; Sandnabba, N. Kenneth; Santtila, Pekka

    2012-01-01

    The present study explored the prevalence of self-reported stuttering in a Finnish twin population and examined the extent to which the variance in liability to stuttering was attributable to genetic and environmental effects. We analyzed data of 1728 Finnish twins, born between 1961 and 1989. The participants were asked to complete a…

  20. How Do Friends Influence Smoking Uptake? Findings from Qualitative Interviews with Identical Twins

    Science.gov (United States)

    McLeod, Kim; White, Victoria; Mullins, Robyn; Davey, Claire; Wakefield, Melanie; Hill, David

    2008-01-01

    The smoking behavior of friends is a major risk factor for adolescent smoking uptake. To explore the social context of smoking experimentation and consolidation with a particular focus on friends, the authors interviewed both members of 14 young adult identical twin pairs who were discordant for smoking. The different smoking status of twins was…

  1. Mental Representations of Attachment in Identical Female Twins with and without Conduct Problems

    Science.gov (United States)

    Constantino, John N.; Chackes, Laura M.; Wartner, Ulrike G.; Gross, Maggie; Brophy, Susan L.; Vitale, Josie; Heath, Andrew C.

    2006-01-01

    Insecure mental representations of attachment, a nearly invariant feature of cluster B personality disorders, have never previously been studied in twins. We conducted the Adult Attachment Interview (AAI) on 33 pairs of monozygotic (MZ) female twins reared together as an initial exploration of causal influences on mental representations of…

  2. Genetic and Environmental Effects on Stuttering: A Twin Study from Finland

    Science.gov (United States)

    Rautakoski, Pirkko; Hannus, Therese; Simberg, Susanna; Sandnabba, N. Kenneth; Santtila, Pekka

    2012-01-01

    The present study explored the prevalence of self-reported stuttering in a Finnish twin population and examined the extent to which the variance in liability to stuttering was attributable to genetic and environmental effects. We analyzed data of 1728 Finnish twins, born between 1961 and 1989. The participants were asked to complete a…

  3. How Do Friends Influence Smoking Uptake? Findings from Qualitative Interviews with Identical Twins

    Science.gov (United States)

    McLeod, Kim; White, Victoria; Mullins, Robyn; Davey, Claire; Wakefield, Melanie; Hill, David

    2008-01-01

    The smoking behavior of friends is a major risk factor for adolescent smoking uptake. To explore the social context of smoking experimentation and consolidation with a particular focus on friends, the authors interviewed both members of 14 young adult identical twin pairs who were discordant for smoking. The different smoking status of twins was…

  4. What Determines Emotional Well-Being? : The Role of Adverse Experiences: Evidence Using Twin Data

    NARCIS (Netherlands)

    V.V. Misheva (Violeta)

    2016-01-01

    markdownabstractIn this paper we use twin data from Australia to explore emotional well-being and its determinants. We aim to accomplish three things. First of all, using twin-fixed effects, and purging the estimates of common family environment and genetic similarities, we can test the robustness o

  5. [MaRS Project

    Science.gov (United States)

    Aruljothi, Arunvenkatesh

    2016-01-01

    The Space Exploration Division of the Safety and Mission Assurances Directorate is responsible for reducing the risk to Human Space Flight Programs by providing system safety, reliability, and risk analysis. The Risk & Reliability Analysis branch plays a part in this by utilizing Probabilistic Risk Assessment (PRA) and Reliability and Maintainability (R&M) tools to identify possible types of failure and effective solutions. A continuous effort of this branch is MaRS, or Mass and Reliability System, a tool that was the focus of this internship. Future long duration space missions will have to find a balance between the mass and reliability of their spare parts. They will be unable take spares of everything and will have to determine what is most likely to require maintenance and spares. Currently there is no database that combines mass and reliability data of low level space-grade components. MaRS aims to be the first database to do this. The data in MaRS will be based on the hardware flown on the International Space Stations (ISS). The components on the ISS have a long history and are well documented, making them the perfect source. Currently, MaRS is a functioning excel workbook database; the backend is complete and only requires optimization. MaRS has been populated with all the assemblies and their components that are used on the ISS; the failures of these components are updated regularly. This project was a continuation on the efforts of previous intern groups. Once complete, R&M engineers working on future space flight missions will be able to quickly access failure and mass data on assemblies and components, allowing them to make important decisions and tradeoffs.

  6. Twinning across the Developing World.

    Directory of Open Access Journals (Sweden)

    Jeroen Smits

    Full Text Available BACKGROUND: Until now, little was known about the variation in incidence of twin births across developing countries, because national representative data was lacking. This study provides the first comprehensive overview of national twinning rates across the developing world on the basis of reliable survey data. METHODS: Data on incidence of twinning was extracted from birth histories of women aged 15-49 interviewed in 150 Demographic and Health Surveys, held between 1987 and 2010 in 75 low and middle income countries. During the interview, information on all live births experienced by the women was recorded, including whether it was a singleton or multiple birth. Information was available for 2.47 million births experienced by 1.38 million women in a period of ten years before the interview. Twinning incidence was measured as the number of twin births per thousand births. Data for China were computed on the basis of published figures from the 1990 census. Both natural and age-standardized twinning rates are presented. RESULTS/CONCLUSIONS: The very low natural twinning rates of 6-9 per thousand births previously observed in some East Asian countries turn out to be the dominant pattern in the whole South and South-East Asian region. Very high twinning rates of above 18 per thousand are not restricted to Nigeria (until now seen as the world's twinning champion but found in most Central-African countries. Twinning rates in Latin America turn out to be as low as those in Asia. Changes over time are small and not in a specific direction. SIGNIFICANCE: We provide the most complete and comparable overview of twinning rates across the developing world currently possible.

  7. Twinning and heteropaternity in chimpanzees (Pan troglodytes).

    Science.gov (United States)

    Ely, John J; Frels, William I; Howell, Sue; Izard, M Kay; Keeling, Michale E; Lee, D Rick

    2006-05-01

    Unlike monozygotic (MZ) twins, dizygotic (DZ) twins develop from separate ova. The resulting twins can have different sires if the fertilizing sperm comes from different males. Routine paternity testing of a pair of same-sexed chimpanzee twins born to a female housed with two males indicated that the twins were sired by two different males. DNA typing of 22 short-tandem repeat (STR) loci demonstrated that these twins were not MZ twins but heteropaternal DZ twins. Reproductive data from 1926-2002 at five domestic chimpanzee colonies, including 52 twins and two triplets in 1,865 maternities, were used to estimate total twinning rates and the MZ and DZ components. The average chimpanzee MZ twinning rate (0.43%) equaled the average human MZ rate (0.48%). However, the chimpanzee DZ twinning rate (2.36%) was over twice the human average, and higher than all but the fertility-enhanced human populations of Nigeria. Similarly high twinning rates among African chimpanzees indicated that these estimates were not artifacts of captivity. Log-linear analyses of maternal and paternal effects on recurrent twinning indicated that females who twinned previously had recurrence risks five times greater than average, while evidence for a paternal twinning effect was weak. Chimpanzee twinning rates appear to be elevated relative to corresponding estimated human rates, making twinning and possibly heteropaternity more important features of chimpanzee reproductive biology than previously recognized.

  8. Twin Legacies: Victor and Vincent McKusick/Twin Studies: Twinning Rates I; Twinning Rates II; MZ Twin Discordance for Russell-Silver Syndrome; Twins' Language Skills/Headlines: Babies Born to Identical Twin Couples; Identity Exchange; Death of Princess Ashraf (Twin); Yahoo CEO Delivers Identical Twins.

    Science.gov (United States)

    Segal, Nancy L

    2016-04-01

    The lives of the illustrious monozygotic (MZ) twins, Victor A. and Vincent L. McKusick, are described. Victor earned the distinction as the 'Father of Medical Genetics', while Vincent was a legendary Chief Justice of the Maine Supreme Court. This dual biographical account is followed by two timely reports of twinning rates, a study of MZ twin discordance for Russell-Silver Syndrome (RSS) and a study of twins' language skills. Twin stories in the news include babies born to identical twin couples, a case of switched identity, the death of Princess Ashraf (Twin) and a new mother of twins who is also Yahoo's CEO.

  9. Estimating twin concordance for bivariate competing risks twin data

    DEFF Research Database (Denmark)

    Scheike, Thomas Harder; Holst, Klaus Kähler; von Bornemann Hjelmborg, Jacob

    2014-01-01

    For twin time-to-event data, we consider different concordance probabilities, such as the casewise concordance that are routinely computed as a measure of the lifetime dependence/correlation for specific diseases. The concordance probability here is the probability that both twins have experienced...... over time, and covariates may be further influential on the marginal risk and dependence structure. We establish the estimators large sample properties and suggest various tests, for example, for inferring familial influence. The method is demonstrated and motivated by specific twin data on cancer...... the event of interest. Under the assumption that both twins are censored at the same time, we show how to estimate this probability in the presence of right censoring, and as a consequence, we can then estimate the casewise twin concordance. In addition, we can model the magnitude of within pair dependence...

  10. Interactive 3D Mars Visualization

    Science.gov (United States)

    Powell, Mark W.

    2012-01-01

    The Interactive 3D Mars Visualization system provides high-performance, immersive visualization of satellite and surface vehicle imagery of Mars. The software can be used in mission operations to provide the most accurate position information for the Mars rovers to date. When integrated into the mission data pipeline, this system allows mission planners to view the location of the rover on Mars to 0.01-meter accuracy with respect to satellite imagery, with dynamic updates to incorporate the latest position information. Given this information so early in the planning process, rover drivers are able to plan more accurate drive activities for the rover than ever before, increasing the execution of science activities significantly. Scientifically, this 3D mapping information puts all of the science analyses to date into geologic context on a daily basis instead of weeks or months, as was the norm prior to this contribution. This allows the science planners to judge the efficacy of their previously executed science observations much more efficiently, and achieve greater science return as a result. The Interactive 3D Mars surface view is a Mars terrain browsing software interface that encompasses the entire region of exploration for a Mars surface exploration mission. The view is interactive, allowing the user to pan in any direction by clicking and dragging, or to zoom in or out by scrolling the mouse or touchpad. This set currently includes tools for selecting a point of interest, and a ruler tool for displaying the distance between and positions of two points of interest. The mapping information can be harvested and shared through ubiquitous online mapping tools like Google Mars, NASA WorldWind, and Worldwide Telescope.

  11. The politics of Mars

    Science.gov (United States)

    Schmitt, Harrison H.

    1986-01-01

    A discussion is presented comparing past and present major accomplishments of the U.S. and the Soviet Union in space. It concludes that the Soviets are presently well ahead of the U.S. in several specific aspects of space accomplishment and speculates that the Soviet strategy is directed towards sending a man to the vicinity of Mars by the end of this century. A major successful multinational space endeavor, INTELSAT, is reviewed and it is suggested that the manned exploration of Mars offers a unique opportunity for another such major international cooperative effort. The current attitude of U.S. leadership and the general public is assessed as uniformed or ambivalent about the perceived threat of Soviet dominance in space.

  12. Confronting Twin Paradox Acceleration

    Science.gov (United States)

    Murphy, Thomas W.

    2016-05-01

    The resolution to the classic twin paradox in special relativity rests on the asymmetry of acceleration. Yet most students are not exposed to a satisfactory analysis of what exactly happens during the acceleration phase that results in the nonaccelerated observer's more rapid aging. The simple treatment presented here offers both graphical and quantitative solutions to the problem, leading to the correct result that the acceleration-induced age gap is 2Lβ years when the one-way distance L is expressed in light-years and velocity β ≡v/c .

  13. Holographic twin Higgs model.

    Science.gov (United States)

    Geller, Michael; Telem, Ofri

    2015-05-15

    We present the first realization of a "twin Higgs" model as a holographic composite Higgs model. Uniquely among composite Higgs models, the Higgs potential is protected by a new standard model (SM) singlet elementary "mirror" sector at the sigma model scale f and not by the composite states at m_{KK}, naturally allowing for m_{KK} beyond the LHC reach. As a result, naturalness in our model cannot be constrained by the LHC, but may be probed by precision Higgs measurements at future lepton colliders, and by direct searches for Kaluza-Klein excitations at a 100 TeV collider.

  14. Oliver Sacks: Our Correspondence About Twins/Twin Research: Vanishing Twins Syndrome; Discordant Sex in MZ Twins; Pregnancy Outcomes in IVF and ICSI Conceived Twins/Print and Media: Superfetated Twins; Twins Discordant for Smoking; Twins in Fashion; Yale University Twin Hockey Players; Conjoined Twin-Visiting Professor.

    Science.gov (United States)

    Segal, Nancy L

    2017-08-01

    The late neurologist and author, Oliver Sacks, published an insightful 1986 review of Marjorie Wallace's book, The Silent Twins, in the New York Times. Taking exception to his assertion about Sir Francis Galton, I wrote a letter to the Times' editor. The letter was unpublished, but it brought a wonderful response from Sacks himself that is reproduced and examined. Next, brief reviews of twin research concerning the vanishing twin syndrome (VTS), discordant sex in a monozygotic (MZ) twin pair, and multiple pregnancy outcomes from assisted reproductive technology (ART) are presented. This section is followed by popular coverage of superfetated twins, smoking-discordant co-twins, twins in fashion, Yale University twin hockey players, and a visiting professor who was a conjoined twin.

  15. NASA Facts, Mars as a Planet.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC. Educational Programs Div.

    Presented is one of a series of National Aeronautics and Space Administration (NASA) facts about the exploration of Mars. Photographs, showing Mars as seen from Earth through a telescope, show dark markings and polar caps present. Photographs from Mariner 7, Mariner 4, and Mariner 9 are included. Presented is a composite of several Mariner 9…

  16. Navigation services of the Mars Network

    Science.gov (United States)

    Ely, T. A.; Guinn, J.; Quintanilla, E.

    2003-01-01

    The Mars Network provides proximity based communications and navigation services to support Mars exploration. The network will be comprised of science orbiters with a MN relay transceiver, and potentially, dedicated telecommunication orbiters. The common MN transceiver, called Electra, is currently in deployment, and is being designed for both communications and radiometric tracking.

  17. Twin Studies of Atopic Dermatitis

    DEFF Research Database (Denmark)

    Elmose, Camilla; Thomsen, Simon Francis

    2015-01-01

    Aim. The aim of this study was to conduct a systematic review of population-based twin studies of (a) the concordance and heritability of AD and (b) the relationship between AD and asthma and, furthermore, to reinterpret findings from previous twin studies in the light of the emerging knowledge a...

  18. Twin methodology in epigenetic studies

    DEFF Research Database (Denmark)

    Tan, Qihua; Christiansen, Lene; von Bornemann Hjelmborg, Jacob

    2015-01-01

    Since the final decades of the last century, twin studies have made a remarkable contribution to the genetics of human complex traits and diseases. With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis ...

  19. Twin Higgs WIMP Dark Matter

    CERN Document Server

    García, Isabel García; March-Russell, John

    2015-01-01

    Dark matter (DM) without a matter asymmetry is studied in the context of Twin Higgs (TH) theories in which the LHC naturalness problem is addressed. These possess a twin sector related to the Standard Model (SM) by a (broken) $\\mathbb{Z}_2$ symmetry, and interacting with the SM via a specific Higgs portal. We focus on the minimal realisation of the TH mechanism, the Fraternal Twin Higgs, with only a single generation of twin quarks and leptons, and $SU(3)'\\times SU(2)'$ gauge group. We show that a variety of natural twin-WIMP DM candidates are present (directly linked to the weak scale by naturalness), the simplest and most attractive being the $\\tau^\\prime$ lepton with a mass $m_{\\tau^\\prime} > m_{\\rm Higgs}/2$, although spin-1 $W^{\\prime\\pm}$ DM and multicomponent DM are also possible (twin baryons are strongly disfavoured by tuning). We consider in detail the dynamics of the possibly (meta)stable glueballs in the twin sector, the nature of the twin QCD phase transition, and possible new contributions to th...

  20. Hypertensive disorders in twin pregnancy

    NARCIS (Netherlands)

    J.G. Santema (Job); E. Koppelaar (Elin); H.C.S. Wallenburg (Henk)

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending th

  1. A Computational Discriminability Analysis on Twin Fingerprints

    Science.gov (United States)

    Liu, Yu; Srihari, Sargur N.

    Sharing similar genetic traits makes the investigation of twins an important study in forensics and biometrics. Fingerprints are one of the most commonly found types of forensic evidence. The similarity between twins’ prints is critical establish to the reliability of fingerprint identification. We present a quantitative analysis of the discriminability of twin fingerprints on a new data set (227 pairs of identical twins and fraternal twins) recently collected from a twin population using both level 1 and level 2 features. Although the patterns of minutiae among twins are more similar than in the general population, the similarity of fingerprints of twins is significantly different from that between genuine prints of the same finger. Twins fingerprints are discriminable with a 1.5%~1.7% higher EER than non-twins. And identical twins can be distinguished by examine fingerprint with a slightly higher error rate than fraternal twins.

  2. Dramatically different dizygotic twins: will we include them in Research? Twin research reviews: congenital anomalies, mirror-image effects in conjoined twins, older mothers of twins; Twin statistics: 'Massachusetts, land of twins'; Tribute: Dr Victor A. McKusick.

    Science.gov (United States)

    Segal, Nancy L

    2008-10-01

    The increased frequency of interracial marriage is a likely source of unusual-looking dizygotic (DZ) twins. Some members of DZ twin pairs born to mixed-race couples inherit very different physical features from their parents. This raises several questions, such as: Will researchers wish to include such twins in their ongoing studies? Next, new twin research concerned with congenital anomalies, mirror-image effects in conjoined twins and older mothers of twins will be reviewed. New statistics on twinning rates in Massachusetts will also be summarized, followed by a tribute to the late medical geneticist Dr. Victor A. McKusick.

  3. Knowledge data base system for twins study.

    Science.gov (United States)

    Reina, S; Miozza, F

    1994-01-01

    The medical research on twins, carried out at the Gregor Mendel Institute for Medical Genetics and Twin Study in Rome over the past four decades, has resulted in a vast collection of clinical paper records. A challenge was presented by the need for a more secure method of storage to preserve this enormously valuable historical and scientific patrimony and to render its contents more easily accessible for research purposes. We met the challenge by planning and developing the computerization of this material. New concepts, currently being explored in biomedical informatics, were applied to build a Knowledge Data Base System, using a fourth-generation language (SQL). This architecturally innovative computer system enables its users to manipulate data supplied, rather than just simply storing it. Based on heuristic relational criteria between variables and parameters, the system is employed to solve problems of sibling design analysis typically arising from twins' records, but is also equipped to meet future data base requirements. Another feature of the system is its users' ability to pull off data in the form of regular automated reports, which are distributed through a Local Area Network (LAN). Through a Bulletin Board System (BBS) and modem, any scientist (outside as well as within the Institute) is thus able to access data and exchange scientific information.

  4. [Hereditary phaeochromocytoma in twins].

    Science.gov (United States)

    Tóth, Géza; Patócs, Attila; Tóth, Miklós

    2016-08-01

    Phaeochromocytoma is a tumor of the catecholamine-producing cells of the adrenal gland. Extraadrenal phaeochromocytomas are frequently called paragangliomas. The majority of phaeochromocytomas are sporadic, however, about 25-30% are caused by genetic mutation. These tumor are frequently referred as hereditary phaeochromocytomas/paragangliomas. Their incidence increases continuously which can be attributed to availability of genetic examination and to the discovery of novel genes. The 47-year-old female patient underwent abdominal computed tomography which revealed bilateral adrenal gland enlargement. Abdominal magnetic resonance imaging, the 131-I- metaiodobenzylguanidine scintigraphy, urinary catecholamines and serum chomogranin A measurements confirmed the diagnosis of bilateral phaeochromocytomas. The genetically identical twin sister of the patient was also diagnosed with hormonally active bilateral phaechromocytoma, suggesting the genetic origin of phaeochromocytoma. Mutation screening confirmed a germline mutation of the transmembrane protein 127 tumorsupressor gene in both patients. Both patients underwent cortical-sparing adrenalectomy. The adrenal gland with the larger tumor was totally resected, while in the opposite side only the tumor was resected and a small part of the cortex was saved. After the operation urinary catecholamines and serum chromogranin A returned to normal in both patients. Adrenocortical deficiency was absent in the first patient, but her sister developed adrenal insufficiency requiring glucocorticoid replacement. To the best of the authors' knowledge phaeochromocytoma affecting twins has never been described earlier. Genetic examination performed in siblings confirmed the presence of the mutant gene through four generations. Orv. Hetil., 2016, 157(33), 1326-1330.

  5. Technology Development for Human Exploration Beyond LEO in the New Millennium IAA-13-3 Strategies and Plans for Human Mars Missions

    Science.gov (United States)

    Larson, William E.; Lueck, Dale E.; Parrish, Clyde F.; Sanders, Gerald B.; Trevathan, Joseph R.; Baird, R. Scott; Simon, Tom; Peters, T.; Delgado, H. (Technical Monitor)

    2001-01-01

    As we look forward into the new millennium, the extension of human presence beyond Low-Earth Orbit (LEO) looms large in the plans of NASA. The Agency's Strategic Plan specifically calls out the need to identify and develop technologies for 100 and 1000-day class missions beyond LEO. To meet the challenge of these extended duration missions, it is important that we learn how to utilize the indigenous resources available to us on extraterrestrial bodies. This concept, known as In-Situ Resource Utilization (ISRU) can greatly reduce the launch mass & cost of human missions while reducing the risk. These technologies may also pave the way for the commercial development of space. While no specific target beyond LEO is identified in NASA's Strategic Plan, mission architecture studies have been on-going for the Moon, Mars, Near-Earth Asteroids and Earth/Moon & Earth/Sun Libration Points. As a result of these studies, the NASA Office of Space Flight (Code M) through the Johnson and Kennedy Space Centers, is leading the effort to develop ISRU technologies and systems to meet the current and future needs of human missions beyond LEO and on to Mars. This effort also receives support from the NASA Office of Biological and Physical Research (Code U), the Office of Space Science (Code S), and the Office of Aerospace Technology (Code R). This paper will present unique developments in the area of fuel and oxidizer production, breathing air production, water production, C02 collection, separation of atmospheric gases, and gas liquefaction and storage. A technology overview will be provided for each topic along with the results achieved to date, future development plans, and the mission architectures that these technologies support.

  6. Human Mars Ascent Configuration and Design Sensitivities

    Science.gov (United States)

    Polsgrove, Tara P.; Gernhardt, Mike; Collins, Tim; Martin, John

    2017-01-01

    Human missions to Mars may utilize several small cabins where crew members could live for days up to a couple of weeks. At the end of a Mars surface mission the Mars Ascent Vehicle (MAV) crew cabin would carry the crew to their destination in orbit in a matter of hours or days. Other small cabins in support of a Mars mission would include pressurized rovers that allow crew members to travel great distances from their primary habitat on Mars while unconstrained by time limits of typical EVAs. An orbital crew taxi could allow for exploration of the moons of Mars with minimum impact to the primary Earth-Mars transportation systems. A common crew cabin design that can perform in each of these applications is desired and could reduce the overall mission cost. However, for the MAV, the crew cabin size and mass can have a large impact on vehicle design and performance. The total ascent vehicle mass drives performance requirements for the Mars descent systems and the Earth to Mars transportation elements. Minimizing MAV mass is a priority and minimizing the crew cabin size and mass is one way to do that. This paper explores the benefits and impacts of using a common crew cabin design for the MAV. Results of a MAV configuration trade study will be presented along with mass and performance estimates for the selected design.

  7. Twins and Kindergarten Separation: Divergent Beliefs of Principals, Teachers, Parents, and Twins

    Science.gov (United States)

    Gordon, Lynn Melby

    2015-01-01

    Should principals enforce mandatory separation of twins in kindergarten? Do school separation beliefs of principals differ from those of teachers, parents of twins, and twins themselves? This survey questioned 131 elementary principals, 54 kindergarten teachers, 201 parents of twins, and 112 twins. A majority of principals (71%) believed that…

  8. Paternal age and telomere length in twins

    DEFF Research Database (Denmark)

    Hjelmborg, Jacob B; Dalgård, Christine; Mangino, Massimo

    2015-01-01

    . Based on two independent (discovery and replication) twin studies, comprising 889 twin pairs, we show an increase in the resemblance of leukocyte telomere length between dizygotic twins of older fathers, which is not seen in monozygotic twins. This phenomenon might result from a paternal age...

  9. Recipient twin limb ischemia with postnatal onset.

    Science.gov (United States)

    Broadbent, Roland Spencer

    2007-02-01

    After the occurrence of 3 local cases of limb ischemia in newborn twins, we reviewed the literature to investigate this combination systematically. This review reveals a distinct condition: postnatal onset limb ischemia affecting recipient twins in twin-twin transfusion syndrome.

  10. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

    The children's book "Two Is for Twins" celebrates twins and illustrates the many "twos" in a child's world. The uniqueness of twos does not have to mean separate classrooms for twins in child development programs, preschool, or elementary school settings. With recent dramatic increases in the US twin population, how should educators address the…

  11. Best Practices for Twin Placement in School

    Science.gov (United States)

    Lacina, Jan

    2012-01-01

    The children's book "Two Is for Twins" celebrates twins and illustrates the many "twos" in a child's world. The uniqueness of twos does not have to mean separate classrooms for twins in child development programs, preschool, or elementary school settings. With recent dramatic increases in the US twin population, how should educators address the…

  12. Twin Higgs Asymmetric Dark Matter.

    Science.gov (United States)

    García García, Isabel; Lasenby, Robert; March-Russell, John

    2015-09-18

    We study asymmetric dark matter (ADM) in the context of the minimal (fraternal) twin Higgs solution to the little hierarchy problem, with a twin sector with gauged SU(3)^{'}×SU(2)^{'}, a twin Higgs doublet, and only third-generation twin fermions. Naturalness requires the QCD^{'} scale Λ_{QCD}^{'}≃0.5-20  GeV, and that t^{'} is heavy. We focus on the light b^{'} quark regime, m_{b^{'}}≲Λ_{QCD}^{'}, where QCD^{'} is characterized by a single scale Λ_{QCD}^{'} with no light pions. A twin baryon number asymmetry leads to a successful dark matter (DM) candidate: the spin-3/2 twin baryon, Δ^{'}∼b^{'}b^{'}b^{'}, with a dynamically determined mass (∼5Λ_{QCD}^{'}) in the preferred range for the DM-to-baryon ratio Ω_{DM}/Ω_{baryon}≃5. Gauging the U(1)^{'} group leads to twin atoms (Δ^{'}-τ^{'}[over ¯] bound states) that are successful ADM candidates in significant regions of parameter space, sometimes with observable changes to DM halo properties. Direct detection signatures satisfy current bounds, at times modified by dark form factors.

  13. Twin methodology in epigenetic studies.

    Science.gov (United States)

    Tan, Qihua; Christiansen, Lene; von Bornemann Hjelmborg, Jacob; Christensen, Kaare

    2015-01-01

    Since the final decades of the last century, twin studies have made a remarkable contribution to the genetics of human complex traits and diseases. With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis of diseases to molecular phenotypes in functional genomics especially in epigenetics, a thriving field of research that concerns the environmental regulation of gene expression through DNA methylation, histone modification, microRNA and long non-coding RNA expression, etc. The application of the twin method to molecular phenotypes offers new opportunities to study the genetic (nature) and environmental (nurture) contributions to epigenetic regulation of gene activity during developmental, ageing and disease processes. Besides the classical twin model, the case co-twin design using identical twins discordant for a trait or disease is becoming a popular and powerful design for epigenome-wide association study in linking environmental exposure to differential epigenetic regulation and to disease status while controlling for individual genetic make-up. It can be expected that novel uses of twin methods in epigenetic studies are going to help with efficiently unravelling the genetic and environmental basis of epigenomics in human complex diseases.

  14. Mars @ ASDC

    Science.gov (United States)

    Carraro, Francesco

    "Mars @ ASDC" is a project born with the goal of using the new web technologies to assist researches involved in the study of Mars. This project employs Mars map and javascript APIs provided by Google to visualize data acquired by space missions on the planet. So far, visualization of tracks acquired by MARSIS and regions observed by VIRTIS-Rosetta has been implemented. The main reason for the creation of this kind of tool is the difficulty in handling hundreds or thousands of acquisitions, like the ones from MARSIS, and the consequent difficulty in finding observations related to a particular region. This led to the development of a tool which allows to search for acquisitions either by defining the region of interest through a set of geometrical parameters or by manually selecting the region on the map through a few mouse clicks The system allows the visualization of tracks (acquired by MARSIS) or regions (acquired by VIRTIS-Rosetta) which intersect the user defined region. MARSIS tracks can be visualized both in Mercator and polar projections while the regions observed by VIRTIS can presently be visualized only in Mercator projection. The Mercator projection is the standard map provided by Google. The polar projections are provided by NASA and have been developed to be used in combination with APIs provided by Google The whole project has been developed following the "open source" philosophy: the client-side code which handles the functioning of the web page is written in javascript; the server-side code which executes the searches for tracks or regions is written in PHP and the DB which undergoes the system is MySQL.

  15. The vector-like twin Higgs

    Science.gov (United States)

    Craig, Nathaniel; Knapen, Simon; Longhi, Pietro; Strassler, Matthew

    2016-07-01

    We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models.

  16. The Vector-like Twin Higgs

    CERN Document Server

    Craig, Nathaniel; Longhi, Pietro; Strassler, Matthew

    2016-01-01

    We present a version of the twin Higgs mechanism with vector-like top partners. In this setup all gauge anomalies automatically cancel, even without twin leptons. The matter content of the most minimal twin sector is therefore just two twin tops and one twin bottom. The LHC phenomenology, illustrated with two example models, is dominated by twin glueball decays, possibly in association with Higgs bosons. We further construct an explicit four-dimensional UV completion and discuss a variety of UV completions relevant for both vector-like and fraternal twin Higgs models.

  17. Cosmology in Mirror Twin Higgs and Neutrino Masses

    CERN Document Server

    Chacko, Zackaria; Fox, Patrick J; Harnik, Roni

    2016-01-01

    We explore a simple solution to the cosmological challenges of the original Mirror Twin Higgs (MTH) model that leads to interesting implications for experiment. We consider theories in which both the standard model and mirror neutrinos acquire masses through the familiar seesaw mechanism, but with a low right-handed neutrino mass scale of order a few GeV. In these $\

  18. Fivefold twinned boron carbide nanowires.

    Science.gov (United States)

    Fu, Xin; Jiang, Jun; Liu, Chao; Yuan, Jun

    2009-09-01

    Chemical composition and crystal structure of fivefold twinned boron carbide nanowires have been determined by electron energy-loss spectroscopy and electron diffraction. The fivefold cyclic twinning relationship is confirmed by systematic axial rotation electron diffraction. Detailed chemical analysis reveals a carbon-rich boron carbide phase. Such boron carbide nanowires are potentially interesting because of their intrinsic hardness and high temperature thermoelectric property. Together with other boron-rich compounds, they may form a set of multiply twinned nanowire systems where the misfit strain could be continuously tuned to influence their mechanical properties.

  19. Failure of vincristine induce twinning

    Science.gov (United States)

    Binder, M.

    1984-01-01

    Mammalian ova do not contain axes of symmetry from which are derived embryonic axes of symmetry. Mammalian axis determination is an early embryologic event occurring at about the time that monozygous twinning in mice. (Kaufma MH & O'Shea KS, 1978, Nature 276:707) and an attempt was made to reproduce their work in several strains of mice. Over 3200 embryos were examined without any twins being found. To rule out the possibility that vincristine caused twinning plus some lethal malformation (with subsequent resorption of the embryo) the embryos were examined 36-60 hours after vincristine treatment.

  20. MNSM - A Future Mars Network Science Mission

    Science.gov (United States)

    Chicarro, A. F.

    2012-04-01

    Following ESA' s successful Mars Express mission, European efforts in Mars Exploration are now taking place within the joint ESA-NASA Mars Exploration Programme, starting in 2016 with the Trace Gases Orbiter (TGO) focusing on atmospheric trace gases and in particular methane, and with the Entry and Descent Module (EDM). In 2018, a joint NASA-ESA rover will perform sample caching as well as geological, geochemical and exobiological measurements of the surface and the subsurface of Mars. A number of missions for 2020 and beyond are currently under study. Among those, a possible candidate is a Mars Network Science Mission (MNSM) of 3-6 surface stations, to investigate the interior of the planet, its rotational parameters and its atmospheric dynamics. These important science goals have not been fully addressed by Mars exploration so far and can only be achieved with simultaneous measurements from a number of landers located on the surface of the planet such as a Mars Network mission. In addition, the geology, mineralogy and astrobiological significance of each landing site would be addressed, as three new locations on Mars would be reached. Such Mars Network Science Mission has been considered a significant priority by the planetary science community worldwide for the past two decades. In fact, a Mars Network mission concept has a long heritage, as it was studied a number of times by ESA, NASA and CNES (e.g., Marsnet, Intermarsnet, Netlander and MarsNEXT mission studies) since 1990. Study work has been renewed in ESA recently with MNSM Science and Engineering Teams being set up to update the scientific objectives of the mission and to evaluate its technical feasibility, respectively. The current mission baseline includes three ESA-led small landers with a robotic arm to be launched with a Soyuz rocket and direct communications to Earth (no need of a dedicated orbiter). However, a larger network could be put in place through international collaboration, as several

  1. Tantsuõpetajate twist ja twin Taanis / Anu Sööt

    Index Scriptorium Estoniae

    Sööt, Anu, 1957-

    2015-01-01

    Taanis toimunud rahvusvahelisest tantsuhariduse kongressist, mille teema oli sel aastal „Twist ja Twin. Exploring Identities in Dance” („Pöörlemine ja ühendumine. Laiendades tantsu identiteeti”).

  2. Tantsuõpetajate twist ja twin Taanis / Anu Sööt

    Index Scriptorium Estoniae

    Sööt, Anu, 1957-

    2015-01-01

    Taanis toimunud rahvusvahelisest tantsuhariduse kongressist, mille teema oli sel aastal „Twist ja Twin. Exploring Identities in Dance” („Pöörlemine ja ühendumine. Laiendades tantsu identiteeti”).

  3. Relationships between sucretolerance and salinotolerance in bacteria from hypersaline environments and their implications for the exploration of Mars and the icy worlds

    Science.gov (United States)

    Fredsgaard, Casper; Moore, Donald B.; Al Soudi, Amer F.; Crisler, James D.; Chen, Fei; Clark, Benton C.; Schneegurt, Mark A.

    2017-04-01

    The most extremely osmotolerant microbial isolates are fungi from high-sugar environments that tolerate the lowest water activity (0.61) for growth yet reported. Studies of osmotolerant bacteria have focused on halotolerance rather than sucretolerance (ability to grow in high sugar concentrations). A collection of salinotolerant (>=10% NaCl or >=50% MgSO4) bacterial isolates from the Great Salt Plains of Oklahoma and Hot Lake in Washington were screened for sucretolerance in medium supplemented with >=50% fructose, glucose or sucrose. Tolerances significantly differed between solutes, even though water activities for saline media (0.92 and 0.85 for 10 and 20% NaCl Salt Plains media, respectively) were comparable or lower than water activities for high-sugar media (0.93 and 0.90 for 50 and 70% sucrose artificial nectar media, respectively). These specific solute effects were differentially expressed among individual isolates. Extrapolating the results of earlier food science studies with yeasts at high sugar concentrations to bacteria in salty environments with low water activity should be done with caution. Furthermore, the discussion of habitable Special Regions on Mars and the icy worlds should reflect an understanding of specific solute effects.

  4. Mars Mission Surface Operation Simulation Testing of Lithium-Ion Batteries

    Science.gov (United States)

    Smart, M. C.; Bugga, R.; Whitcanack, L. D.; Chin, K. B.; Davies, E. D.; Surampudi, S.

    2003-01-01

    The objectives of this program are to 1) Assess viability of using lithium-ion technology for future NASA applications, with emphasis upon Mars landers and rovers which will operate on the planetary surface; 2) Support the JPL 2003 Mars Exploration Rover program to assist in the delivery and testing of a 8 AHr Lithium-Ion battery (Lithion/Yardney) which will power the rover; 3) Demonstrate applicability of using lithium-ion technologyfor future Mars applications: Mars 09 Science Laboratory (Smart Lander) and Future Mars Surface Operations (General). Mission simulation testing was carried out for cells and batteries on the Mars Surveyor 2001 Lander and the 2003 Mars Exploration Rover.

  5. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the devel

  6. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the

  7. Twin-to-twin transfusion syndrome : from placental anastomoses to long-term outcome

    NARCIS (Netherlands)

    Lopriore, Enrico

    2006-01-01

    Twin-to-twin transfusion syndrome (TTTS) is a severe complication of monochorionic twin pregnancies associated with high perinatal mortality and morbidity rates. Placental vascular anastomoses, almost invariably present in monochorionic placentas, are the essential anatomical substrate for the devel

  8. Constructing an Educational Mars Simulation

    Science.gov (United States)

    Henke, Stephen A.

    2004-01-01

    January 14th 2004, President George Bush announces his plans to catalyst the space program into a new era of space exploration and discovery. His vision encompasses a robotics program to explore our solar system, a return to the moon, the human exploration of Mars, and to promote international prosperity towards our endeavors. We at NASA now have the task of constructing this vision in a very real timeframe. I have been chosen to begin phase 1 of making this vision a reality. I will be working on creating an Educational Mars Simulation of human exploration of Mars to stimulate interest and involvement with the project from investors and the community. GRC s Computer Services Division (CSD) in collaboration with the Office of Education Programs will be designing models, constructing terrain, and programming this simulation to create a realistic portrayal of human exploration on mars. With recent and past technological breakthroughs in computing, my primary goal can be accomplished with only the aid of 3-4 software packages. Lightwave 3D is the modeling package we have selected to use for the creation of our digital objects. This includes a Mars pressurized rover, rover cockpit, landscape/terrain, and habitat. Once we have the models completed they need textured so Photoshop and Macromedia Fireworks are handy for bringing these objects to life. Before directly importing all of this data into a simulation environment, it is necessary to first render a stunning animation of the desired final product. This animation with represent what we hope to capture out of the simulation and it will include all of the accessories like ray-tracing, fog effects, shadows, anti-aliasing, particle effects, volumetric lighting, and lens flares. Adobe Premier will more than likely be used for video editing and adding ambient noises and music. Lastly, V-Tree is the real-time 3D graphics engine which will facilitate our realistic simulation. Additional information is included in the

  9. Five Years of Stereo Magnetospheric Imaging by TWINS

    Science.gov (United States)

    Goldstein, J.; McComas, D. J.

    2013-12-01

    Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) is the first stereoscopic magnetospheric imager. TWINS is a NASA Explorer Mission of Opportunity performing simultaneous energetic neutral atom (ENA) imaging from two widely-separated Molniya orbits on two different spacecraft, and providing nearly continuous coverage of magnetospheric ENA emissions. The ENA imagers observe energetic neutrals produced from global ion populations, over a broad energy range (1-100 keV/u) with high angular (4∘×4∘) and time (about 1-minute) resolution. TWINS distinguishes hydrogen ENAs from oxygen ENAs. Each TWINS spacecraft also carries a Lyman- α geocoronal imager to monitor the cold exospheric hydrogen atoms that produce ENAs from ions via charge exchange. Complementing the imagers are detectors that measure the local charged particle environment around the spacecraft. During its first five years of science operations, TWINS has discovered new global properties of geospace plasmas and neutrals, fostered understanding of causal relationships, confirmed theories and predictions based on in situ data, and yielded key insights needed to improve geospace models. Analysis and modeling of TWINS data have: (1) obtained continuous (main phase through recovery) global ion spectra, (2) revealed a previously unknown local-time dependence of global pitch angle, (3) developed quantitative determination of ion fluxes from low altitude ENAs (4) determined dynamic connections between local pitch angle and global ion precipitation, (5) confirmed local-time dependence of precipitating ion temperature, (6) imaged global dynamic heating of the magnetosphere, (7) explained why the oxygen ring current survives longer into recovery than hydrogen, and (8) revealed new global exospheric density features and their influence upon ring current decay rates. Over the next several years of the solar cycle, TWINS observations of three-dimensional (3D) global ion dynamics, composition, origins and

  10. Simultaneous Intussusception in Monozygotic Twins

    Directory of Open Access Journals (Sweden)

    Mete Kaya

    2014-12-01

    Full Text Available In this case report, it was aimed to present the simultaneously occurring intussusception in the monozygotic twins. In addition to genetic predisposition, environmental factors has been hypothesized to be responsible for the development of the disease.

  11. Discordant Epilepsy in Monozygous Twins

    OpenAIRE

    2001-01-01

    Twelve monozygotic twins, discordant for epilepsy, were analysed for nonhereditary etiological factors by clinical history, MRI, and quantitative brain volume studies at the Brain Research Institute, University of Melbourne, Victoria, Australia.

  12. Hypertensive disorders in twin pregnancy

    OpenAIRE

    Santema, Job; Koppelaar, Elin; Wallenburg, Henk

    1995-01-01

    textabstractObjective: To compare the incidence and severity of pregnancy-induced hypertensive disorders in twin pregnancy and in singleton gestation. Study design: Case-control study in the setting of a University Hospital. Each pregnancy of a consecutive series of 187 twin pregnancies attending the antenatal clinic and booked before a gestational age of 24 weeks was matched for maternal age, parity, and gestational age at delivery with a singleton pregnancy delivered in the same year. Prima...

  13. Europe's eye on Mars: first spectacular results from Mars Express

    Science.gov (United States)

    2004-01-01

    Although the seven scientific instruments on board Mars Express are still undergoing a thorough calibration phase, they have already started collecting amazing results. The first high-resolution images and spectra of Mars have already been acquired. This first spectacular stereoscopic colour picture was taken on 14 January 2004 by ESA’s Mars Express satellite from 275 km above the surface of Mars by the High Resolution Stereo Camera (HRSC). This image is available on the ESA portal at: http://mars.esa.int The picture shows a portion of a 1700 km long and 65 km wide swath which was taken in south-north direction across the Grand Canyon of Mars (Valles Marineris). It is the first image of this size that shows the surface of Mars in high resolution (12 metres per pixel), in colour, and in 3D. The total area of the image on the Martian surface (top left corner) corresponds to 120 000 km². The lower part of the picture shows the same region in perspective view as if seen from a low-flying aircraft. This perspective view was generated on a computer from the original image data. One looks at a landscape which has been predominantly shaped by the erosional action of water. Millions of cubic kilometres of rock have been removed, and the surface features seen now such as mountain ranges, valleys, and mesas, have been formed. The HRSC is just one of the instruments to have collected exciting data. To learn more about the very promising beginning to ESA's scientific exploration of Mars, media representatives are invited to attend a press conference on Friday, 23 January 2004, at 11:00 CET at ESA’s Space Operations Centre in Darmstadt, Germany, and in video-conference with the other ESA centres. There, under the auspices of ESA Council Chair at Ministerial level, Germany's Minister for Education and Research, Mrs Edelgard Bulmahn, ESA's Director of the Scientific Programme, Prof. David Southwood and the Principal Investigators of all instruments on board Mars Express will

  14. Light-toned salty soils and co-existing Si-rich species discovered by the Mars Exploration Rover Spirit in Columbia Hills

    Science.gov (United States)

    Wang, Alian; Bell, J.F.; Li, Ron; Johnson, J. R.; Farrand, W. H.; Cloutis, E.A.; Arvidson, R. E.; Crumpler, L.; Squyres, S. W.; McLennan, S.M.; Herkenhoff, K. E.; Ruff, S.W.; Knudson, A.T.; Chen, Wei; Greenberger, R.

    2008-01-01

    Light-toned soils were exposed, through serendipitous excavations by Spirit Rover wheels, at eight locations in the Columbia Hills. Their occurrences were grouped into four types on the basis of geomorphic settings. At three major exposures, the light-toned soils are hydrous and sulfate-rich. The spatial distributions of distinct types of salty soils vary substantially: with centimeter-scaled heterogeneities at Paso Robles, Dead Sea, Shredded, and Champagne-Penny, a well-mixed nature for light-toned soils occurring near and at the summit of Husband Hill, and relatively homogeneous distributions in the two layers at the Tyrone site. Aeolian, fumarolic, and hydrothermal fluid processes are suggested to be responsible for the deposition, transportation, and accumulation of these light-toned soils. In addition, a change in Pancam spectra of Tyrone yellowish soils was observed after being exposed to current Martian surface conditions for 175 sols. This change is interpreted to be caused by the dehydration of ferric sulfates on the basis of laboratory simulations and suggests a relative humidity gradient beneath the surface. Si-rich nodules and soils were observed near the major exposures of S-rich soils. They possess a characteristic feature in Pancam visible near-infrared (Vis-NIR) spectra that may be diagnostic of hydrated species, and this spectral feature can be used to search for additional Si-rich species. The exposures of hydrated salty soils within various geomorphic settings imply the potential existence of hydrous minerals in similar settings over a much wider area. Hydrous sulfates represent one of the candidates that may contribute the high level of water equivalent hydrogen in equatorial regions detected by the Neutron Spectrometer on Mars Odyssey.

  15. Europe is going to Mars

    Science.gov (United States)

    1999-06-01

    The Agency's Science Programme Committee (SPC) approved Mars Express after ESA's Council, meeting at ministerial level in Brussels on 11 and 12 May, had agreed the level of the science budget for the next 4 years, just enough to make the mission affordable. "Mars Express is a mission of opportunity and we felt we just had to jump in and do it. We are convinced it will produce first-rate science", says Hans Balsiger, SPC chairman. As well as being a first for Europe in Mars exploration, Mars Express will pioneer new, cheaper ways of doing space science missions. "With a total cost of just 150 million euros, Mars Express will be the cheapest Mars mission ever undertaken", says Roger Bonnet, ESA's Director of Science. Mars Express will be launched in June 2003. When it arrives at the red planet six months later, it will begin to search for water and life. Seven instruments, provided by space research institutes throughout Europe, will make observations from the main spacecraft as it orbits the planet. Just before the spacecraft arrives, it will release a small lander, provided by research institutes in the UK, that will journey on to the surface to look for signs of life. The lander is called Beagle 2 after the ship in which Charles Darwin sailed round the world in search of evidence supporting his theory of evolution. But just as Darwin had to raise the money for his trip, so the search is on for public and private finance for Beagle 2. "Beagle 2 is an extremely important element of the mission", says Bonnet. Europe's space scientists have envisaged a mission to Mars for over fifteen years. But limited funding has prevented previous proposals from going ahead. The positioning of the planets in 2003, however, offers a particularly favourable passage to the red planet - an opportunity not to be missed. Mars Express will be joined by an international flotilla of spacecraft that will also be using this opportunity to work together on scientific questions and pave the way

  16. Increased Science Instrumentation Funding Strengthens Mars Program

    Science.gov (United States)

    Graham, Lee D.; Graff, T. G.

    2012-01-01

    As the strategic knowledge gaps mature for the exploration of Mars, Mars sample return (MSR), and Phobos/Deimos missions, one approach that becomes more probable involves smaller science instrumentation and integrated science suites. Recent technological advances provide the foundation for a significant evolution of instrumentation; however, the funding support is currently too small to fully utilize these advances. We propose that an increase in funding for instrumentation development occur in the near-term so that these foundational technologies can be applied. These instruments would directly address the significant knowledge gaps for humans to Mars orbit, humans to the Martian surface, and humans to Phobos/ Deimos. They would also address the topics covered by the Decadal Survey and the Mars scientific goals, objectives, investigations and priorities as stated by the MEPAG. We argue that an increase of science instrumentation funding would be of great benefit to the Mars program as well as the potential for human exploration of the Mars system. If the total non-Earth-related planetary science instrumentation budget were increased 100% it would not add an appreciable amount to the overall NASA budget and would provide the real potential for future breakthroughs. If such an approach were implemented in the near-term, NASA would benefit greatly in terms of science knowledge of the Mars, Phobos/Deimos system, exploration risk mitigation, technology development, and public interest.

  17. Simulation of tantalum nanocrystals under shock-wave loading: Dislocations and twinning

    Science.gov (United States)

    Tramontina, D. R.; Hahn, E. N.; Meyers, M. A.; Bringa, E. M.

    2017-01-01

    We simulate strong shock waves in nanocrystalline tantalum using atomistic molecular dynamics simulations, for particle velocities in the range 0.35-2.0 km s-1, which induce pressures in the range 20-195 GPa. Our simulations explore strain rates in the range 108 s-1 - 1010 s-1, and lead to a peak strength in the range 3-15 GPa. Nanocrystalline tantalum exposed to strong shock waves demonstrates deformation enabled by concomitant dislocations, twinning, and grain boundary activity at a variety of particle velocities. Twinning is observed for a mean grain size of 7 nm, starting at around 32 GPa, in disagreement with models which predict a Hall-Petch behavior for twinning, i.e. a twinning stress scaling with grain size d as d-0.5, and supporting the presence of an inverse Hall-Petch effect for twinning at small grain sizes.

  18. Human Mars Landing Site and Impacts on Mars Surface Operations

    Science.gov (United States)

    Hoffman, Stephen J.; Bussey, Ben

    2016-01-01

    This paper describes NASA's initial steps for identifying and evaluating candidate Exploration Zones (EZs) and Regions of Interests (ROIs) for the first human crews that will explore the surface of Mars. NASA's current effort to define the exploration of this planet by human crews, known as the Evolvable Mars Campaign (EMC), provides the context in which these EZs and ROIs are being considered. The EMC spans all aspects of a human Mars mission including launch from Earth, transit to and from Mars, and operations on the surface of Mars. An EZ is a collection of ROIs located within approximately 100 kilometers of a centralized landing site. ROIs are areas relevant for scientific investigation and/or development/maturation of capabilities and resources necessary for a sustainable human presence. The EZ also contains one or more landing sites and a habitation site that will be used by multiple human crews during missions to explore and utilize the ROIs within the EZ. With the EMC as a conceptual basis, the EZ model has been refined to a point where specific site selection criteria for scientific exploration and in situ resource utilization can be defined. In 2015 these criteria were distributed to the planetary sciences community and the in situ resource utilization and civil engineering communities as part of a call for EZ proposals. The resulting "First Landing Site/Exploration Zone Workshop for Human Missions to the Surface of Mars" was held in October 2015 during which 47 proposals for EZs and ROIs were presented and discussed. Proposed locations spanned all longitudes and all allowable latitudes (+/- 50 degrees). Proposed justification for selecting one of these EZs also spanned a significant portion of the scientific and resource criteria provided to the community. Several important findings resulted from this Workshop including: (a) a strong consensus that, at a scale of 100 km (radius), multiple places on Mars exist that have both sufficient scientific interest

  19. The International Mars Data Base

    Science.gov (United States)

    Slavney, S.; Arvidson, R. E.; Eichentopf, K.; Natenzon, M.; Kirsanova, T.; Tarnopolsky, V.

    1996-03-01

    The next five years will witness the beginning of a period of unprecedented activity and interest in the exploration of Mars. Numerous missions are scheduled involving a broad array of spacecraft and instrumentation, and several important experiments will depend on international collaborations. They include Mars Global Surveyor and Pathfinder to be launched in 1996, along with the Russian Mars 96 Mission. Through the Mars Surveyor Program, a lander will descend to the south polar latitudes in 1999 while an orbiter circles the planet and acquires images and infrared data. These missions will produce a welcome deluge of new data, as well as a sharp increase in the demand for data from past Mars missions. One result of this increased activity will be the need for a rapid, efficient system for sharing new data with the scientific community after the proprietary periods have elapsed. With the boom in growth of the Internet, it is now possible to design a system for international access using ordinary laboratory and desktop computers. The advantage of using the World-Wide Web as the basis for such a system is that the infrastructure is already in place, as many users are already accustomed to using Web browsers to locate and transfer information.

  20. Information bulletin of the bureau of hydrocarbons exploration-production (BEPH) - March 2008; Bulletin d'information du BEPH. Mars 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This newsletter takes stock of the recent highlights in the domain of hydrocarbons exploration and production in the French territory: mining domain (demands, allocations and extension of research permits and concessions; list of demands under instruction), drilling activity (new drillings, advance of existing exploratory and extension-development drillings); production activity (interventions on wells, crude oil, crude gas, commercialized gas, natural gas-derived hydrocarbons, related products, production shares by company in the Paris and Aquitain basins). (J.S.)

  1. Looking at Dauphiné twins in vein quartz as a potential paleostress indicator

    Science.gov (United States)

    Sintubin, Manuel; Wenk, Hans-Rudolf

    2013-04-01

    Paleostress studies commonly call upon (1) a fault slip data inversion technique, (2) a calcite twin stress inversion technique, (3) recrystallized grain size piezometry for quartz, or (4) direct measurements of residual lattice strain. Recent advances in orientation imaging microscopy (OIM) using electron backscatter diffraction (EBSD) on a scanning electron microscope (SEM) have revealed that Dauphiné twinning is very common in quartz in naturally deformed quartz-bearing rocks in a wide range of tectonometamorphic conditions. It has long been known that mechanical Dauphiné twinning in quartz can be stress-induced. Based on the results of an extensive EBSD-OIM analysis on vein quartz, taken from well-studied early to late-orogenic veins in the High-Ardenne slate belt (Germany, Belgium), we explore the potential use of mechanical Dauphiné twins as a paleostress indicator, possibly completing our toolbox for reconstructing paleostresses in the Earth's crust. The vein quartz studied precipitated in low-grade tectonometamorphic conditions (~200-400°C), typical for the brittle-plastic transition zone at the base of the seismogenic crust (~7-15km). Quartz has only been weakly affected by low to moderate temperature (200 to 400°C) crystal-plastic deformation. The samples show grains with a high concentration of Dauphiné twin boundaries and others free of twin boundaries, thus being untwinned or completely twinned. This pattern depends on the crystallographic orientation. Twin boundaries are arrested by grain or subgrain boundaries, suggesting that Dauphiné twinning occurred on a pre-existing fabric that resulted from crystal-plastic deformation. An analysis of the orientation distribution of the rhombs in the twinned variant domains of individual quartz (sub-)grains reveals a particular preferred orientation of the poles to rhombs. We will discuss the possible significance of these observations with respect to paleostresses that may have caused the mechanical

  2. Estimating twin concordance for bivariate competing risks twin data.

    Science.gov (United States)

    Scheike, Thomas H; Holst, Klaus K; Hjelmborg, Jacob B

    2014-03-30

    For twin time-to-event data, we consider different concordance probabilities, such as the casewise concordance that are routinely computed as a measure of the lifetime dependence/correlation for specific diseases. The concordance probability here is the probability that both twins have experienced the event of interest. Under the assumption that both twins are censored at the same time, we show how to estimate this probability in the presence of right censoring, and as a consequence, we can then estimate the casewise twin concordance. In addition, we can model the magnitude of within pair dependence over time, and covariates may be further influential on the marginal risk and dependence structure. We establish the estimators large sample properties and suggest various tests, for example, for inferring familial influence. The method is demonstrated and motivated by specific twin data on cancer events with the competing risk death. We thus aim to quantify the degree of dependence through the casewise concordance function and show a significant genetic component.

  3. Spina bifida occulta and monozygotic twins.

    Science.gov (United States)

    Spacca, Barbara; Buxton, Neil

    2008-10-01

    Central nervous system maldevelopment can have different presentations in twins. We report on a case of different presentations of spina bifida occulta in monozygotic twins. The first twin presented at birth with a lipomyelomeningocele; a tethered cord was diagnosed in the second twin at 2 years of age. Neural tube defects (NTDs) are a group of common congenital malformations of the brain and spine generated during neurulation. The genetic basis of this process is still not well known. Whenever an NTD is diagnosed in one of a pair of twins, the other twin should also be evaluated for NTDs.

  4. [Twin dystocia: about one case of compaction].

    Science.gov (United States)

    Desseauve, D; Voluménie, J-L

    2008-09-01

    We report a case of twin dystocia during the evacuation of full-term fetus both in cephalic presentation. A low-outlet forceps for second-phase arrest was performed for the first twin but the head remained stuck to maternal perineum, mimicking a shoulder dystocia. Digital examination found a twin compaction, that is the presence of the second twin's fetal head at the level of the first twin's chest. The discrepancy between fetal weights and the use of forceps could favor this rare complication. Various maneuvers were described previously attempted to solve the problem. Forcing back the second head may help to achieve delivery of the first twin.

  5. [The Chinese national twin cohort: an update].

    Science.gov (United States)

    Gao, W J; Li, L M

    2017-06-10

    The importance of large cohort studies in China has been increasingly emphasized. As special group in the population, twins provide excellent natural resources since they share the same birthday, maternal intrauterine environment and early family environment. Twin cohorts are unique for and benefit on controlling the confounding factors as age, gender (same-sex twins), genetic background (monozygotic twins) or early environment (being raised together) in the etiological studies on complex diseases. In this review, we briefly introduce the objectives, current situation, challenges and opportunities related to the Chinese national twin cohort, focusing on the characteristics of twins that are different from other groups in the general population.

  6. TWIN GESTATION : A CHALLENGING TASK

    Directory of Open Access Journals (Sweden)

    Vrunda V.

    2015-03-01

    Full Text Available INTRODUCTION In the era of modern obstetrics when multiple pregnancies are on increase it is very important to know the incidence and obstetric outcomes of twin deliveries. Twin pregnancy is still associated with increased maternal and perinatal morbidity and mortality as well as healthcare costs . ( 1 , 2 , 3 MATERIALS AND METHODS : This is a r etrospective study of twin deliveries done in the rural medical college teaching hospital over a period of 3 years. RESULTS : During the study period , incidence of twin delivery was 19.37 per 1000 deliveries. Majority cases of twins were young primies in ag e group (20 - 30 years . Preterm delivery occurred in 68% cases and was therefore , the most common morbidity followed by anaemia (38% and PIH (28%. Most common presentation was vertex (66% and malpresentation were present in 44% of cases. 54% were deliver ed by caesarean section. In 88% second baby delivered within 15 minutes. Uterine inertia , PROM , fetal distress , PPH , cord prolapse and abruption were complications during labour. There was no maternal mortality in present study. Average weight of first baby was 1679.63 gms and 2 nd baby was 1586.94 gms. Perinatal mortality of 1 st baby was 27.55 for 1 st baby and 37.25% for 2 nd baby . Average gestational age for patients in whom cervical encirclage was done was 34 weeks. CONCLUSION: P reterm delivery and low birth weight babies are main challenges to the obstetrician. Incidence of LSCS is quite high with malpresentation of leading (twin A baby is a major indication for LSCS . The use of antenatal care services and good intrapartum mana gement will help improve outcome in twin pregnancies.

  7. The fracture behavior of twinned Cu nanowires: A molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jiapeng, E-mail: sun.jiap@gmail.com [College of Mechanics and Materials, Hohai University, Nanjing 210098 (China); Fang, Liang [State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an 710049, Shaanxi Province (China); Ma, Aibin, E-mail: aibin-ma@hhu.edu.cn [College of Mechanics and Materials, Hohai University, Nanjing 210098 (China); Jiang, Jinghua [College of Mechanics and Materials, Hohai University, Nanjing 210098 (China); Han, Ying [Key Laboratory of Advanced Structural Materials, Ministry of Education, Changchun University of Technology, Changchun 130012, Jilin Province (China); Chen, Huawei [Department of Applied Physics, School of Science, Xi’an Jiaotong University, Xi’an 710049, Shaanxi Province (China); Han, Jing [School of Mechanical and Electrical Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu Province (China)

    2015-05-14

    The molecular dynamics simulations are performed to explore the fracture behavior and the ductility of the twinned Cu nanowires containing orthogonally oriented growth CTBs due to the uniaxial tensile deformation. The results reveal that, the fracture behavior and the ductility of the twinned nanowires are not related to the length of the nanowires but also intensively related to the twin boundary spacing. When the twin boundary space is changed, the twinned nanowires undergo three distinct failure modes which include ductile fracture, brittle fracture and ductile-to-brittle transition depending on the length of the nanowires. We also find a reduction in the ductility of the twinned nanowires, which is ascribed to the deformation localization induced by the Lomer dislocation and the rapid necking resulted from the twinning partial slipping. Finally, the atomic-level process that occurs during deformation until final fracture are examined in detail, and a new formation mechanism of the Lomer dislocation is observed when a 90° partial dislocation transmits across a coherent twin boundary.

  8. Twin-twin transfusion syndrome: neurodevelopmental screening test

    Directory of Open Access Journals (Sweden)

    Amabile Vessoni Arias

    2015-03-01

    Full Text Available Objective To assess the neurodevelopmental functions (cognition, language and motor function of survivors of twin-twin transfusion syndrome (TTTS. Method Observational cross-sectional study of a total of 67 monochorionic diamniotic twins who underwent fetoscopic laser coagulation (FLC for treatment of TTTS. The study was conducted at the Center for Investigation in Pediatrics (CIPED, Universidade Estadual de Campinas. Ages ranged from one month and four days to two years four months. Bayley Scales of Infant and Toddler Development Screening Test-III, were used for evaluation. Results Most children reached the competent category and were classified as having appropriate performance. The preterm children scored worse than term infants for gross motor subtest (p = 0.036. Conclusion The majority of children reached the expected development according to their age. Despite the good neurodevelopment, children classified at risk should be monitored for development throughout childhood.

  9. Individual Differences in Dynamic Measures of Verbal Learning Abilities in Young Twin Pairs and Their Older Siblings

    Science.gov (United States)

    van Soelen, Inge L. C.; van den Berg, Stephanie M.; Dekker, Peter H.; van Leeuwen, Marieke; Peper, Jiska S.; Hulshoff Pol, Hilleke E.; Boomsma, Dorret I.

    2009-01-01

    We explored the genetic background of individual differences in dynamic measures of verbal learning ability in children, using a Dutch version of the Auditory Verbal Learning Test (AVLT). Nine-year-old twin pairs (N = 112 pairs) were recruited from the Netherlands Twin Register. When possible, an older sibling between 10 and 14 years old…

  10. Individual Differences in Dynamic Measures of Verbal Learning Abilities in Young Twin Pairs and Their Older Siblings

    Science.gov (United States)

    van Soelen, Inge L. C.; van den Berg, Stephanie M.; Dekker, Peter H.; van Leeuwen, Marieke; Peper, Jiska S.; Hulshoff Pol, Hilleke E.; Boomsma, Dorret I.

    2009-01-01

    We explored the genetic background of individual differences in dynamic measures of verbal learning ability in children, using a Dutch version of the Auditory Verbal Learning Test (AVLT). Nine-year-old twin pairs (N = 112 pairs) were recruited from the Netherlands Twin Register. When possible, an older sibling between 10 and 14 years old…

  11. TWIN PREGNANCY WITH ACARDIUS ANCEPS

    Directory of Open Access Journals (Sweden)

    Padma

    2014-02-01

    Full Text Available Acardiac twin is an anomaly unique to monochorionic multiple pregnancies, characterized by formation of malformed fetus with an absent or rudimentary (nonfunctional heart. Acardiac twinning, often results from abnormal placental vascular anastomoses. A 20 year old primigravida admitted to the department of Obstetrics and Gynecology S .S. Medical College, Rewa, on 26th July 2012 at the gestation of 34 week with spontaneous monochorionic monoamniotic twin pregnancy and fetal acardius with oligohydramnios. Patient was taking her treatment from private Hospital; acardius was diagnosed at 27 week due to late booking. In view of oligohydramnios and hypoxic changes in color Doppler, elective LSCS was done on 28/7/13 at 34 week 2 day, after betnesol coverage. She delivered a live, healthy, female child with good APGAR score having apparently no congenital anomaly, with a birth weight of 2.3 kg .The other twin was fetus acardius, of about900 gm. with head and face partially developed . Upper limb was rudimentary and lower limb was partially developed and malformed. External genitalia were developed as female. Placenta was monochorionic and monoamniotic, weighing500 gm. The umbilical cord of the normal twin was20 cm with central attachment, while the other umbilical cord was10 cm long with peripheral attachment

  12. TwinMux Testing System

    CERN Document Server

    Wong, Wei Wen; CERN. Geneva. PH Department

    2015-01-01

    During the CERN summer school program, I joined the CMS Muon Drift Tube (DT) group, and mainly worked on two projects, which, both of them, are related to the electronics of a new data concentrator called the “TwinMux”. My first task within the TwinMux project was to build an integrated software test station in order to run several tests on the functionality of the TwinMux hardware. Essentially, I had to integrate existing testing scripts, adding several new ones, into a single user-friendly testing platform which can perform quick, convenient and automated hardware testing. Later, I was also involved in the design of the local technical triggering of the DT. Such system relies on some firmware functionality built in the TwinMux and controlled by software. I had attempted two different approaches to design the communication topology of all the 12 TwinMux cards in order to send a user-defined logical operation to the read-out electronics. The final goal of this system is to drive local trigger signal for...

  13. Complications arising in twin pregnancy: findings of prenatal ultrasonography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Ah; Cho, Jeong Yeon; Lee, Young Ho; Song, Mi Jin; Min, Jee Yeon; Lee, Hak Jong; Han, Byoung Hee; Lee, Kyung Sang; Cho, Byung Jae; Chun, Yi Kyeong [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2003-03-01

    Multifetal gestations are high-risk pregnancies involving higher perinatal morbidity and mortality, and are subject to unique complications including twin oligohydramnios- polyhydramnios sequence, twin-to-twin transfusion syndrome, acardiac twins, conjoined twins, co-twin demise, and heterotopic pregnancies. The purpose of this study is to describe the prenatal ultrasonographic and pathologic findings of these complications.

  14. SABIOS, EXPLORADORES Y ARTESANOS. AMALGAMAS DEL PASADO EN LA MAR DEL PLATA DE PRIMERA MITAD DEL SIGLO XX (1924-1954 / Wise men, explorers and craftsmen. Amalgams of the past in the Mar del Plata of the first half of the 20th century (1924-1954.

    Directory of Open Access Journals (Sweden)

    Irene Elena Brichetti

    2014-11-01

    Full Text Available Este artículo analiza la relación entre ciencia, cultura y política, considerando las gestiones realizadas por autoridades políticas del ámbito municipal y la actividad de naturalistas aficionados en Mar del Plata – provincia de Buenos Aires- durante la primera mitad del siglo XX. El trabajo muestra como una figura preponderante en la escena científica nacional e internacional como la de Florentino Ameghino funcionó a nivel local como modelo moral al cual se le atribuyeron características ejemplares. Dicha imagen se relacionó con la de exploradores autodidactas tales como los integrantes de la familia de Lorenzo Scaglia, quienes se dedicaron a la exploración del pasado natural y humano más lejano de la región. Los aspectos mencionados se pusieron de manifiesto en la prensa gráfica así como en distintos eventos públicos tales como el acto y el desfile inaugural por la instalación de un busto en homenaje a Florentino Ameghino, la exposición en el Salón Witcomb de la Rambla Bristol de los restos fósiles hallados por Lorenzo Scaglia y la formación del primer museo público municipal.   Palabras clave: ciencia, estado, modelo moral, sabios, autodidactas.     Abstract This paper Analyzes the relationship between culture, politics and science taking into account the efforts of political authorities and the activities of amateur naturalists in Mar del Plata (General Pueyrredón, during the first half of the 20th century. This article shows how a great figure in the national as well as international scientific scene such as Florentino Ameghino had function as a model of local morality of exemplary characteristics. The above mentioned image was amalgamated with that of explorers and such self-taught naturalists as the members of the family Scaglia, who dedicated his life to the exploration of the most distant natural and human past of the region. These aspects were revealed in such different public events as the act and inaugural

  15. Breast-Feeding Twins: Making Feedings Manageable

    Science.gov (United States)

    ... more than one baby? Here's help breast-feeding twins or other multiples, from getting positioned and ensuring ... babies who are born prematurely, as are many twins and higher order multiples. Breast milk is easier ...

  16. Risk of Oral Clefts in Twins

    DEFF Research Database (Denmark)

    Grosen, Dorthe; Bille, Camilla; Petersen, Inge

    2011-01-01

    BACKGROUND:: Small studies have indicated that twinning increases the risk of oral cleft. METHODS:: We used data from a Danish national population-based cohort study to investigate whether twinning was associated with isolated oral cleft, and to estimate the twin probandwise concordance rate...... and heritability. Twins (207 affected/130,710) and singletons (7766 affected/4,798,526) born from 1936 through 2004 in Denmark were ascertained by linkage among the Danish Facial Cleft Database, the Danish Twin Registry, and the Civil Registration System. We computed oral cleft prevalence and prevalence proportion...... ratio for twins versus singletons, stratified for 3 subphenotypes. Probandwise concordance rates and heritability for twins were estimated for 2 phenotypes-cleft lip with or without cleft palate (CL/P) and cleft palate (CP). RESULTS:: The prevalence of oral cleft was 15.8 per 10,000 twins and 16.6 per...

  17. Having Twins? How to Stay Healthy

    Science.gov (United States)

    ... Listen Español Text Size Email Print Share Having Twins? How to Stay Healthy Page Content Article Body ... the eyes of obstetricians. Many would call a twin pregnancy a high-risk pregnancy , but don’t ...

  18. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)

  19. Preterm twin gestation and cystic periventricular leucomalacia

    NARCIS (Netherlands)

    Resch, B; Jammernegg, A; Vollaard, E; Maurer, U; Mueller, WD; Pertl, B

    2004-01-01

    Objective: To identify risk factors for the development of cystic periventricular leucomalacia (PVL) in twin gestation. Design: Retrospective case-control study. Setting: Tertiary care university hospital, Department of Paediatrics, Division of Neonatology, Graz, Austria. Patients: Preterm twin gest

  20. Nike Twins Seven Seven: Nigerian Batik Artist.

    Science.gov (United States)

    LaDuke, Betty

    1987-01-01

    Chronicles the personal and professional life of Nike Twins Seven Seven (born 1951), a Nigerian batik artist, and her husband, Twins Seven Seven, a musician-artist, both of whom have received international acclaim. (BJV)