WorldWideScience

Sample records for degree lunar gravity

  1. GLGM-3: A Degree-ISO Lunar Gravity Model from the Historical Tracking Data of NASA Moon Orbiters

    Science.gov (United States)

    Mazarico, E.; Lemoine, F. G.; Han, Shin-Chan; Smith, D. E.

    2010-01-01

    In preparation for the radio science experiment of the Lunar Reconnaissance Orbiter (LRO) mission, we analyzed the available radio tracking data of previous NASA lunar orbiters. Our goal was to use these historical observations in combination with the new low-altitude data to be obtained by LRO. We performed Precision Orbit Determination on trajectory arcs from Lunar Orbiter 1 in 1966 to Lunar Prospector in 1998, using the GEODYN II program developed at NASA Goddard Space Flight Center. We then created a set of normal equations and solved for the coefficients of a spherical harmonics expansion of the lunar gravity potential up to degree and order 150. The GLGM-3 solution obtained with a global Kaula constraint (2.5 x 10(exp -4)/sq l) shows good agreement with model LP150Q from the Jet Propulsion Laboratory, especially over the nearside. The levels of data fit with both gravity models are very similar (Doppler RMS of approx.0.2 and approx. 1-2 mm/s in the nominal and extended phases, respectiVely). Orbit overlaps and uncertainties estimated from the covariance matrix also agree well. GLGM-3 shows better correlation with lunar topography and admittance over the nearside at high degrees of expansion (l > 100), particularly near the poles. We also present three companion solutions, obtained with the same data set but using alternate inversion strategies that modify the power law constraint and expectation of the individual spherical harmonics coefficients. We give a detailed discussion of the performance of this family of gravity field solutions in terms of observation fit, orbit quality, and geophysical consistency.

  2. GLGM-3: A Degree-ISO Lunar Gravity Model from the Historical Tracking Data of NASA Moon Orbiters

    Science.gov (United States)

    Mazarico, E.; Lemoine, F. G.; Han, Shin-Chan; Smith, D. E.

    2010-01-01

    In preparation for the radio science experiment of the Lunar Reconnaissance Orbiter (LRO) mission, we analyzed the available radio tracking data of previous NASA lunar orbiters. Our goal was to use these historical observations in combination with the new low-altitude data to be obtained by LRO. We performed Precision Orbit Determination on trajectory arcs from Lunar Orbiter 1 in 1966 to Lunar Prospector in 1998, using the GEODYN II program developed at NASA Goddard Space Flight Center. We then created a set of normal equations and solved for the coefficients of a spherical harmonics expansion of the lunar gravity potential up to degree and order 150. The GLGM-3 solution obtained with a global Kaula constraint (2.5 x 10(exp -4)/sq l) shows good agreement with model LP150Q from the Jet Propulsion Laboratory, especially over the nearside. The levels of data fit with both gravity models are very similar (Doppler RMS of approx.0.2 and approx. 1-2 mm/s in the nominal and extended phases, respectiVely). Orbit overlaps and uncertainties estimated from the covariance matrix also agree well. GLGM-3 shows better correlation with lunar topography and admittance over the nearside at high degrees of expansion (l > 100), particularly near the poles. We also present three companion solutions, obtained with the same data set but using alternate inversion strategies that modify the power law constraint and expectation of the individual spherical harmonics coefficients. We give a detailed discussion of the performance of this family of gravity field solutions in terms of observation fit, orbit quality, and geophysical consistency.

  3. Global Lunar Gravity Field Recovery from SELENE

    Science.gov (United States)

    Matsumoto, Koji; Heki, Kosuke; Hanada, Hideo

    2002-01-01

    Results of numerical simulation are presented to examine the global gravity field recovery capability of the Japanese lunar exploration project SELENE (Selenological and Engineering Explorer) which will be launched in 2005. New characteristics of the SELENE lunar gravimetry include four-way satellite-to-satellite Doppler tracking of main orbiter and differential VLBI tracking of two small free-flier satellites. It is shown that planned satellites configuration will improve lunar gravity field in wide range of wavelength as well as far-side selenoid.

  4. Gravity increased by lunar surface temperature

    Science.gov (United States)

    Keene, James

    2013-04-01

    Quantitatively large effects of lunar surface temperature on apparent gravitational force measured by lunar laser ranging (LLR) and lunar perigee may challenge widely accepted theories of gravity. LLR data grouped by days from full moon shows the moon is about 5 percent closer to earth at full moon compared to 8 days before or after full moon. In a second, related result, moon perigees were least distant in days closer to full moon. Moon phase was used as proxy independent variable for lunar surface temperature. The results support the prediction by binary mechanics that gravitational force increases with object surface temperature.

  5. Analysis of the Lunar Gravity Field by Using GL0660B Model and Its Effect on Lunar Satellite Orbit

    Directory of Open Access Journals (Sweden)

    HUANG Kunxue

    2016-07-01

    Full Text Available The lunar gravity field provides a way to research moon's evolution and probes the interior structure of the moon. It is an important factor influencing the lunar satellite precise orbit determination as well. The new lunar gravity model GL0660B from GRAIL mission dramatically improves the gravity spectrum and spectral ranges. Using the model GL0660B, it can be computed that the corresponding degree-wise RMS and correlation of topography, with which the quality of model GL0660B can be analyzed. Then different characters of the lunar gravity field comparing with other lunar gravity fields are analyzed. Besides, gravity anomaly distribution figures at different height of the models are given, and the character and difference of the lunar gravity models at different height are compared. In addition, lunar satellite orbit revolutionary at different height are modeled by GEODYN. The result shows that the trend of lunar satellite eccentricity changes is a complex and long cycle of change trend. It is different affected by the perturbation of the mascons of different height, which causes different changes of apolune, perilune and eccentricity.

  6. The Near Side: Regional Lunar Gravity Field Determination

    NARCIS (Netherlands)

    Goossens, S.

    2005-01-01

    In the past ten years the Moon has come fully back into focus, resulting in missions such as Clementine and Lunar Prospector. Data from these missions resulted in a boost in lunar gravity field modelling. Until this date, the lunar gravity field has mainly been expressed in a global representation,

  7. Orbit determination for Chang'E-2 lunar probe and evaluation of lunar gravity models

    Science.gov (United States)

    Li, PeiJia; Hu, XiaoGong; Huang, Yong; Wang, GuangLi; Jiang, DongRong; Zhang, XiuZhong; Cao, JianFeng; Xin, Nan

    2012-03-01

    tracking data of CE-2 provided evaluations of different lunar gravity models through POD. It is found that for the 100 km×100 km lunar orbit, with a degree and order expansion up to 165, JPL's gravity model LP165P did not show noticeable improvement over Japan's SGM series models (100×100), but for the 15 km×100 km lunar orbit, a higher degree-order model can significantly improve the orbit accuracy.

  8. The interpretation of gravity anomaly on lunar Apennines

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The lunar Apennines,located in the southeast of Mare Imbrium,is the largest range on the Moon. The gravity anomalies on profiles across the mountains reveal evidence of a great fault zone characteristic. The deep crustal structures of lunar Apennines are analyzed on the basis of topographic data from Chang’E-1 satellite and gravity data from Lunar Prospector. The inverted crust-mantle models indicate the presence of a lithosphere fault beneath the mountains. Inverted results of gravity and the hypothe-sis of lunar thermal evolution suggest that the lunar lithosphere might be broken ~3.85 Ga ago due to a certain dynamic lateral movement and compression of lunar lithosphere. This event is associated with the history of magma filling and lithosphere deformation in the mountain zone and adjacent area. Moreover,the formation and evolution of Imbrium basin impose this effect on the process.

  9. The interpretation of gravity anomaly on lunar Apennines

    Institute of Scientific and Technical Information of China (English)

    CHEN Chao; CHEN Bo; PING JinSong; LIANG Qing; HUANG Qian; ZHAO WenJin; ZHANG ChangDa

    2009-01-01

    The lunar Apennines, located in the southeast of Mare Imbrium, is the largest range on the Moon. The gravity anomalies on profiles across the mountains reveal evidence of a great fault zone characteristic.The deep crustal structures of lunar Apennines are analyzed on the basis of topographic data from Chang'E-1 satellite and gravity data from Lunar Prospector. The inverted crust-mantle models indicate the presence of a lithosphere fault beneath the mountains. Inverted results of gravity and the hypothesis of lunar thermal evolution suggest that the lunar lithosphere might be broken ~3.85 Ga ago due to a certain dynamic lateral movement and compression of lunar lithosphere. This event is associated with the history of magma filling and lithosphere deformation in the mountain zone and adjacent area. Moreover, the formation and evolution of Imbrium basin impose this effect on the process.

  10. The perception of verticality in lunar and Martian gravity conditions

    NARCIS (Netherlands)

    Winkel, K.N. de; Clément, G.; Groen, E.L.; Werkhoven, P.J.

    2012-01-01

    Although the mechanisms of neural adaptation to weightlessness and re-adaptation to Earth-gravity have received a lot of attention since the first human space flight, there is as yet little knowledge about how spatial orientation is affected by partial gravity, such as lunar gravity of 0.16. g or Ma

  11. Developments in Lunar Gravity Field Recovery Within the Project GRAZIL

    Science.gov (United States)

    Wirnsberger, Harald; Klinger, Beate; Krauss, Sandro; Mayer-Gürr, Torsten

    2016-10-01

    The project GRAZIL addresses the highly accurate recovery of the lunar gravity field using intersatellite Ka-band ranging (KBR) measurements collected by the Lunar Gravity Ranging System (LGRS) of the Gravity Recovery And Interior Laboratory (GRAIL) mission. Dynamic precise orbit determination is an indispensable task in order to recover the lunar gravity field based on LGRS measurements. The concept of variational equations is adopted to determine the orbit of the two GRAIL satellites based on radio science data. In this contribution we focus on the S-band two-way Doppler data collected by the Deep Space Network.As far as lunar gravity field recovery is concerned, we apply an integral equation approach using short orbital arcs. In this contribution we demonstrate the progress of Graz lunar gravity field models (GrazLGM) from the beginning, till the end of the projet GRAZIL. For the latest GrazLGM version special attention is given to the refinement of our processing strategy in conjunction with an increase of the spectral resolution. Furthermore, we present the first GrazLGM based on KBR observations during the primary and the extended mission phase. Our results are validated against state of the art lunar gravity field models computed at NASA-GSFC and NASA-JPL.

  12. Lunar Prospector Orbit Determination Uncertainties Using the High Resolution Lunar Gravity Models

    Science.gov (United States)

    Carranza, Eric; Konopliv, Alex; Ryne, Mark

    1999-01-01

    The Lunar Prospector (LP) mission began on January 6, 1998, when the LP spacecraft was launched from Cape Canaveral, Florida. The objectives of the mission were to determine whether water ice exists at the lunar poles, generate a global compositional map of the lunar surface, detect lunar outgassing, and improve knowledge of the lunar magnetic and gravity fields. Orbit determination of LP performed at the Jet Propulsion Laboratory (JPL) is conducted as part of the principal science investigation of the lunar gravity field. This paper will describe the JPL effort in support of the LP Gravity Investigation. This support includes high precision orbit determination, gravity model validation, and data editing. A description of the mission and its trajectory will be provided first, followed by a discussion of the orbit determination estimation procedure and models. Accuracies will be examined in terms of orbit-to-orbit solution differences, as a function of oblateness model truncation, and inclination in the plane-of-sky. Long term predictions for several gravity fields will be compared to the reconstructed orbits to demonstrate the accuracy of the orbit determination and oblateness fields developed by the Principal Gravity Investigator.

  13. High Degree and Order Gravity Fields of the Moon Derived from GRAIL Data

    Science.gov (United States)

    Lemoine, F. G.; Goossens, S. J.; Sabaka, T. J.; Nicholas, J. B.; Mazarico, E.; Rowlands, D. D.; Loomis, B. D.; Chinn, D. S.; Caprette, D. S.; McCarthy, J. J.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

    2012-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) spacecraft conducted the mapping of the gravity field of the Moon from March 1, 2012 to May 29, 2012. The twin spacecraft acquired highly precise K Band range-rate (KBRR) intersatellite ranging data and Deep Space Network (DSN) data during this prime mission phase from altitudes of 15 to 75 km above the lunar surface over three lunar months. We have processed these data using the NASA GSFC GEODYN orbit determination and geodetic parameter estimation program, and we have determined gravity fields up to degree and order 420 in spherical harmonics. The new gravity solutions show improved correlations with LOLA-derived topography to high degree and order and resolve many lunar features in the geopotential with a resolution of less than 30 km, including for example the central peak of the crater Tycho. We discuss the methodology used for the processing of the GRAIL data, the quality of the orbit determination on the GRAIL satellites and the derivation of the solutions, and their evaluation with independent data, including Lunar Prospector. We show that with these new GRAIL gravity solutions, we can now fit the low altitude, extended mission Lunar Prospector tracking data better than with any previous gravity model that included the LP data.

  14. The lunar gravity mission MAGIA: preliminary design and performances

    Science.gov (United States)

    Fermi, Marco; Gregnanin, Marco; Mazzolena, Marco; Chersich, Massimiliano; Reguzzoni, Mirko; Sansò, Fernando

    2011-10-01

    The importance of an accurate model of the Moon gravity field has been assessed for future navigation missions orbiting and/or landing on the Moon, in order to use our natural satellite as an intermediate base for next solar system observations and exploration as well as for lunar resources mapping and exploitation. One of the main scientific goals of MAGIA mission, whose Phase A study has been recently funded by the Italian Space Agency (ASI), is the mapping of lunar gravitational anomalies, and in particular those on the hidden side of the Moon, with an accuracy of 1 mGal RMS at lunar surface in the global solution of the gravitational field up to degree and order 80. MAGIA gravimetric experiment is performed into two phases: the first one, along which the main satellite shall perform remote sensing of the Moon surface, foresees the use of Precise Orbit Determination (POD) data available from ground tracking of the main satellite for the determination of the long wavelength components of gravitational field. Improvement in the accuracy of POD results are expected by the use of ISA, the Italian accelerometer on board the main satellite. Additional gravitational data from recent missions, like Kaguya/Selene, could be used in order to enhance the accuracy of such results. In the second phase the medium/short wavelength components of gravitational field shall be obtained through a low-to-low (GRACE-like) Satellite-to-Satellite Tracking (SST) experiment. POD data shall be acquired during the whole mission duration, while the SST data shall be available after the remote sensing phase, when the sub-satellite shall be released from the main one and both satellites shall be left in a free-fall dynamics in the gravity field of the Moon. SST range-rate data between the two satellites shall be measured through an inter-satellite link with accuracy compliant with current state of art space qualified technology. SST processing and gravitational anomalies retrieval shall

  15. Tests of Gravity Using Lunar Laser Ranging

    Directory of Open Access Journals (Sweden)

    Stephen M. Merkowitz

    2010-11-01

    Full Text Available Lunar laser ranging (LLR has been a workhorse for testing general relativity over the past four decades. The three retroreflector arrays put on the Moon by the Apollo astronauts and the French built arrays on the Soviet Lunokhod rovers continue to be useful targets, and have provided the most stringent tests of the Strong Equivalence Principle and the time variation of Newton’s gravitational constant. The relatively new ranging system at the Apache Point 3.5 meter telescope now routinely makes millimeter level range measurements. Incredibly, it has taken 40 years for ground station technology to advance to the point where characteristics of the lunar retroreflectors are limiting the precision of the range measurements. In this article, we review the gravitational science and technology of lunar laser ranging and discuss prospects for the future.

  16. High-degree Gravity Models from GRAIL Primary Mission Data

    Science.gov (United States)

    Lemoine, Frank G.; Goossens, Sander J.; Sabaka, Terence J.; Nicholas, Joseph B.; Mazarico, Erwan; Rowlands, David D.; Loomis, Bryant D.; Chinn, Douglas S.; Caprette, Douglas S.; Neumann, Gregory A.; Smith, David E.; Zuber, Maria T.

    2013-01-01

    We have analyzed Ka?band range rate (KBRR) and Deep Space Network (DSN) data from the Gravity Recovery and Interior Laboratory (GRAIL) primary mission (1 March to 29 May 2012) to derive gravity models of the Moon to degree 420, 540, and 660 in spherical harmonics. For these models, GRGM420A, GRGM540A, and GRGM660PRIM, a Kaula constraint was applied only beyond degree 330. Variance?component estimation (VCE) was used to adjust the a priori weights and obtain a calibrated error covariance. The global root?mean?square error in the gravity anomalies computed from the error covariance to 320×320 is 0.77 mGal, compared to 29.0 mGal with the pre?GRAIL model derived with the SELENE mission data, SGM150J, only to 140×140. The global correlations with the Lunar Orbiter Laser Altimeter?derived topography are larger than 0.985 between l = 120 and 330. The free?air gravity anomalies, especially over the lunar farside, display a dramatic increase in detail compared to the pre?GRAIL models (SGM150J and LP150Q) and, through degree 320, are free of the orbit?track?related artifacts present in the earlier models. For GRAIL, we obtain an a posteriori fit to the S?band DSN data of 0.13 mm/s. The a posteriori fits to the KBRR data range from 0.08 to 1.5 micrometers/s for GRGM420A and from 0.03 to 0.06 micrometers/s for GRGM660PRIM. Using the GRAIL data, we obtain solutions for the degree 2 Love numbers, k20=0.024615+/-0.0000914, k21=0.023915+/-0.0000132, and k22=0.024852+/-0.0000167, and a preliminary solution for the k30 Love number of k30=0.00734+/-0.0015, where the Love number error sigmas are those obtained with VCE.

  17. Probing Gravity with Next Generation Lunar Laser Ranging

    Science.gov (United States)

    Martini, Manuele; Dell'Agnello, Simone

    Lunar and satellite laser ranging (LLR/SLR) are consolidated techniques which provide a precise, and at the same time, cost-effective method to determine the orbits of the Moon and of satellites equipped with laser retroreflectors with respect to the International Celestial Reference System. We describe the precision tests of general relativity and of new theories of gravity that can be performed with second-generation LLR payloads on the surface of the Moon (NASA/ASI MoonLIGHT project), and with SLR/LLR payloads deployed on spacecraft in the Earth-Moon system. A new wave of lunar exploration and lunar science started in 2007-2008 with the launch of three missions (Chang'e by China, Kaguya by Japan, Chandrayaan by India), missions in preparation (LCROSS, LRO, GRAIL/LADEE by NASA) and other proposed missions (like MAGIA in Italy). This research activity will be greatly enhanced by the future robotic deployment of a lunar geophysics network (LGN) on the surface of the Moon. A scientific concept of the latter is the International Lunar Network (ILN, see http://iln.arc.nasa.gov/). The LLR retroreflector payload developed by a US-Italy team described here and under space qualification at the National Laboratories of Frascati (LNF) is the optimum candidate for the LGN, which will be populated in the future by any lunar landing mission.

  18. Probing gravity with the proposed MAGIA and ILN lunar missions.

    Science.gov (United States)

    Garattini, M.; Lops, C.; Dell'Agnello, S.; Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G. O.; Intaglietta, N.; Maiello, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M.; Currie, D. G.; Vittori, R.; Bianco, G.; Murphy, T.; Coradini, A.; Dionisio, C.; March, R.; Bellettini, G.; Tauraso, R.

    MAGIA (Missione Altimetrica Gravimetrica GeochImica Lunare) is a mission approved by the Italian Space Agency (ASI) for Phase A study. Using a single large-diameter laser retroreflector, a large laser retroreflector array and an atomic clock onboard MAGIA, we propose to perform several fundamental physics and absolute positioning metrology experiments: VESPUCCI, an improved test of the gravitational redshift in the Earth-Moon system predicted by General Relativity; MoonLIGHT-P, a precursor test of a second generation Lunar Laser Ranging (LLR) payload for precision gravity Network (ILN). Future ILN geodetic nodes equipped with MoonLIGHT and the Apollo/Lunokhod retroreflectors will become the first realization of the International Moon Reference Frame (IMRF), the lunar analog of the ITRF (International Terrestrial Reference Frame).

  19. GRAIL gravity field recovery using the short-arc integral equation technique: development of the latest Graz lunar gravity field model (GrazLGM)

    Science.gov (United States)

    Krauss, S.; Klinger, B.; Baur, O.; Mayr-Guerr, T.

    2015-10-01

    We present an updated version of the lunar gravity field model GrazLGM300a,b [1,2] based on intersatellite Ka-band ranging (KBR) observations collected by the GRAIL mission. We propose to exploit the ranging measurements by an integral equation approach using short orbital arcs [4].Compared to the predecessor model we increase the spectral resolution to degree and order 450 and refined the parameterization. Validation shows that the applied technique is well suited to recover the lunar gravity field.

  20. Testing Gravity via Lunar Laser Ranging: Maximizing Data Quality

    Science.gov (United States)

    Murphy, Thomas

    We propose to continue leading-edge observations with the Apache Point Observatory Lunar Laser-ranging Operation (APOLLO), in an effort to subject gravity to the most stringent tests yet. APOLLO has delivered a dramatic improvement in the measurement of the lunar orbit: now at the millimeter level. Yet incomplete models are thus far unable to confirm the accuracy. We therefore seek to build a calibration system to ensure that APOLLO meets its millimeter measurement goal. Gravity--the most evident force of nature--is in fact the weakest of the fundamental forces, and consequently the most poorly tested. Einstein’s general relativity, which is currently our best description of gravity, is fundamentally incompatible with quantum mechanics and is likely to be replaced by a more complete theory in the future. A modified theory would predict small deviations in the solar system that could have profound consequences for our understanding of the Universe as a whole. Lunar laser ranging (LLR), in which short laser pulses launched from a telescope are bounced off of reflectors placed on the Moon by U.S. astronauts and Soviet landers, has for decades produced some of the leading tests of gravity by mapping the shape of the lunar orbit to high precision. These include tests of the strong equivalence principle, the time-rate-ofchange of Newton’s gravitational constant, gravitomagnetism, the inverse-square law, and many others. Among the attributes that contribute to APOLLO’s superior observations, routine ranging to all five lunar reflectors on timescales of minutes dramatically improves our ability to gauge lunar orientation and body distortion. This information produces insights into the interior structure and dynamics of the Moon, allowing a more precise determination of the path for the Moon’s center of mass, lending to tests of fundamental gravity. Simultaneously, higher precision range measurements, together with data from a superconducting gravimeter at the

  1. Lunar Crustal Properties: Insights from the GRAIL Gravity Signatures of Lunar Impact Craters

    Science.gov (United States)

    Soderblom, J. M.; Andrews-Hanna, J. C.; Evans, A. J.; Johnson, B. C.; Melosh, J., IV; Milbury, C.; Miljkovic, K.; Nimmo, F.; Phillips, R. J.; Smith, D. E.; Solomon, S. C.; Wieczorek, M. A.; Zuber, M. T.

    2014-12-01

    Impact cratering is a violent process, shattering and melting rock and excavating deep-seated material. The resulting scars are apparent on every planetary surface across our Solar System. Subsurface density variations associated with the resulting impact structures contain clues to aid in unlocking the details of this process. High-resolution gravity fields, such as those derived from the Gravity Recovery and Interior Laboratory (GRAIL) mission, are ideal for investigating these density variations. With gravity measurements from GRAIL and topography from the Lunar Orbiter Laser Altimeter (LOLA), we derived high-resolution Bouguer gravity fields (i.e., the gravity field after the contribution from topography is removed) that we correlated with craters mapped from LOLA data. We found that the mass deficit beneath lunar impact craters relates directly to crater size, up to diameter ~130 km, whereas craters larger than this diameter display no further systematic change. This observation, coupled with the greater depth of impact damage expected beneath larger craters, indicates that some process is affecting the production and/or preservation of porosity at depth or otherwise altering the mean density beneath the larger craters (note, measurable mantle uplift is observed for craters larger than ~184-km diameter). The observed crater gravity anomalies, however, exhibit considerable variation about these mean trends, suggesting that other factors are also important in determining the bulk density of impact crater structures. Milbury et al. (this conference) have demonstrated that pre-impact crustal porosity strongly influences the resulting density contrast between the impact damage zone beneath a crater and its surroundings. Herein, we extend these studies using the same GRAIL- and LOLA-derived maps to further investigate the effects that crustal properties have on the bulk density of the rock beneath lunar impact features. We focus, in particular, on the processes that

  2. Specific heats of lunar surface materials from 90 to 350 degrees Kelvin

    Science.gov (United States)

    Robie, R.A.; Hemingway, B.S.; Wilson, W.H.

    1970-01-01

    The specific heats of lunar samples 10057 and 10084 returned by the Apollo 11 mission have been measured between 90 and 350 degrees Kelvin by use of an adiabatic calorimeter. The samples are representative of type A vesicular basalt-like rocks and of finely divided lunar soil. The specific heat of these materials changes smoothly from about 0.06 calorie per gram per degree at 90 degrees Kelvin to about 0.2 calorie per gram per degree at 350 degrees Kelvin. The thermal parameter ??=(k??C)-1/2 for the lunar surface will accordingly vary by a factor of about 2 between lunar noon and midnight.

  3. Precision Orbit Determination for the Lunar Reconnaissance Orbiter: orbit quality and gravity field estimation

    Science.gov (United States)

    Mazarico, E.; Rowlands, D. D.; Neumann, G. A.; Lemoine, F. G.; Torrence, M. H.; Smith, D. E.; Zuber, M. T.; Mao, D.

    2010-12-01

    We present results of the Precision Orbit Determination work undertaken by the Lunar Orbiter Laser Altimeter (LOLA) Science Team for the Lunar Reconnaissance Orbiter (LRO) mission, in order to meet the position knowledge accuracy requirements (50-m total position) and to precisely geolocate the LRO datasets. In addition to the radiometric tracking data, one-way laser ranges (LR) between Earth stations and the spacecraft are made possible by a small telescope mounted on the spacecraft high-gain antenna. The photons received from Earth are transmitted to one LOLA detector by a fiber optics bundle. The LOLA timing system enables 5-s LR normal points with precision better than 10cm. Other types of geodetic constraints are derived from the altimetric data itself. The orbit geometry can be constrained at the times of laser groundtrack intersections (crossovers). Due to the Moon's slow rotation, orbit solutions and normal equations including altimeter crossovers are processed and created in one month batches. Recent high-resolution topographic maps near the lunar poles are used to produce a new kind of geodetic constraints. Purely geometric, those do not necessitate actual groundtrack intersections. We assess the contributions of those data types, and the quality of our orbits. Solutions which use altimetric crossover meet the horizontal 50-m requirement, and perform usually better (10-20m). We also obtain gravity field solutions based on LRO and historical data. The various LRO data are accumulated into normal equations, separately for each one month batch and for each measurement type, which enables the final weights to be adjusted during the least-squares inversion step. Expansion coefficients to degree and order 150 are estimated, and a Kaula rule is still needed to stabilize the farside field. The gravity field solutions are compared to previous solutions (GLGM-3, LP150Q, SGM100h) and the geopotential predicted from the latest LOLA spherical harmonic expansion.

  4. Latest developments in lunar gravity field recovery within the project GRAZIL

    Science.gov (United States)

    Krauss, Sandro; Wirnsberger, Harald; Klinger, Beate; Mayer-Gürr, Torsten; Baur, Oliver

    2016-04-01

    The project GRAZIL addresses the highly accurate recovery of the lunar gravity field using intersatellite Ka-band ranging (KBR) measurements collected by the Lunar Gravity Ranging System (LGRS) of the Gravity Recovery And Interior Laboratory (GRAIL) mission. Dynamic precise orbit determination is an indispensable task in order to recover the lunar gravity field based on LGRS measurements. The concept of variational equations is adopted to determine the orbit of the two GRAIL satellites based on radio science data. In this contribution we focus on the S-band two-way Doppler data collected by the Deep Space Network. As far as lunar gravity field recovery is concerned, we apply an integral equation approach using short orbital arcs in the order of one hour. In this contribution special attention is given to the refinement of our processing strategy in conjunction with an increase of the spectral resolution. Based on these considerations we present the latest version of a lunar gravity field model developed in Graz which is based on KBR observations during the primary mission phase (March 1 to May 29, 2012). Our results are validated against GRAIL models computed at NASA-GSFC and NASA-JPL.

  5. Periodic Orbits in Rotating Second Degree and Order Gravity Fields

    Institute of Scientific and Technical Information of China (English)

    Wei-Duo Hu; Daniel J.Scheeres

    2008-01-01

    Periodic orbits in an arbitrary 2nd degree and order uniformly rotating gravity field are studied. We investigate the four equilibrium points in this gravity field. We see that close relation exists between the stability of these equilibria and the existence and stability of their nearby periodic orbits. We check the periodic orbits with non-zero periods. In our searching procedure for these periodic orbits, we remove the two unity eigenvalues from the state transition matrix to find a robust, non-singular linear map to solve for the periodic orbits. The algorithm converges well, especially for stable periodic orbits. Using the searching procedure, which is relatively automatic, we find five basic families of periodic orbits in the rotating second degree and order gravity field for planar motion, and discuss their existence and stability at different central body rotation rates.

  6. Bouguer gravity anomaly and isostatic residual gravity maps of the Tonopah 1 degree by 2 degrees Quadrangle, central Nevada

    Science.gov (United States)

    Plouff, Donald

    1992-01-01

    These gravity maps are part of a folio of maps of the Tonopah 1 degree by 2 degrees quadrangle, Nevada, prepared under the Conterminous United States Mineral Assessment Program. Each product of the folio is designated by a different letter symbol, starting with A, in the MF-1877 folio. The quadrangle encompasses an area of about 19,500 km2  in the west central part of Nevada.

  7. Proposed gravity-gradient dynamics experiments in lunar orbit using the RAE-B spacecraft

    Science.gov (United States)

    Blanchard, D. L.; Walden, H.

    1973-01-01

    A series of seven gravity-gradient dynamics experiments is proposed utilizing the Radio Astronomy Explorer (RAE-B) spacecraft in lunar orbit. It is believed that none of the experiments will impair the spacecraft structure or adversely affect the continuation of the scientific mission of the satellite. The first experiment is designed to investigate the spacecraft dynamical behavior in the absence of libration damper action and inertia. It requires stable gravity-gradient capture of the spacecraft in lunar orbit with small amplitude attitude librations as a prerequisite. Four subsequent experiments involve partial retraction, ultimately followed by full redeployment, of one or two of the 230-meter booms forming the lunar-directed Vee-antenna. These boom length change operations will induce moderate amplitude angular librations of the spacecraft.

  8. Pre-impact crustal porosity and its effect on the gravity signature of lunar craters

    Science.gov (United States)

    Milbury, Colleen; Johnson, Brandon C.; Melosh, H. Jay; Collins, Gareth C.; Blair, David M.; Soderblom, Jason M.; Zuber, Maria T.

    2015-04-01

    NASA's dual Gravity Recovery and Interior Laboratory (GRAIL) spacecraft have globally mapped the lunar gravity field at unprecedented resolution. Soderblom et al. [2015] made a comprehensive analysis of the residual and central uplift Bouguer gravity anomalies associated with more than 5200 lunar craters. There were two main observations that are related to the work presented here: 1) craters less than ~150 km in diameter (D) have a residual Bouguer anomaly (BA) that is near zero on average (although a negative trend is observed), but have both positive and negative anomalies that vary by approximately ±25 mGal about the mean, and, 2) there is a transition at which the central uplift BA becomes positive and increases with D. Craters that are located in the maria and South Pole-Aitken (SPA) basin were excluded from the analysis because they tend to have more negative signatures than highlands craters. These gravitational signatures contrast with the invariably negative gravity anomalies associated with terrestrial craters. In this study, we investigate pre-impact porosity by modeling crater formation using the iSALE hydrocode, including a new approach to include dilatancy, to determine their effects on the gravity signature of craters. We calculated the BA for the simulations, but due to mantle uplift alone. We find that the magnitude of the BA increases with increasing porosity, and that variable initial porosity of the lunar crust can explain why craters on the Moon exhibit both positive and negative Bouguer anomalies. This can also explain the observed negative residual BA associated with craters formed in the lunar maria and SPA (and associated melt sheet) because they are typically less porous than the highlands crust. Gravity anomalies due to mantle uplift reproduce the observed transition from zero to a positive central uplift BA, which coincides with the morphological transition from complex craters to peak-ring basins.

  9. Perturbative Degrees of Freedom in Loop Quantum Gravity: Anisotropies

    CERN Document Server

    Bojowald, M; Morales-Tecotl, H A; Bojowald, Martin; Hernandez, Hector H.; Morales-Tecotl, Hugo A

    2006-01-01

    The relation between an isotropic and an anisotropic model in loop quantum cosmology is discussed in detail, comparing the strict symmetry reduction with a perturbative implementation of symmetry. While the latter cannot be done in a canonical manner, it allows to consider the dynamics including the role of small non-symmetric degrees of freedom for the symmetric evolution. This serves as a model for the general situation of perturbative degrees of freedom in a background independent quantization such as loop quantum gravity, and for the more complicated addition of perturbative inhomogeneities. While being crucial for cosmological phenomenology, it is shown that perturbative non-symmetric degrees of freedom do not allow definitive conclusions for the singularity issue and in such a situation could even lead to wrong claims.

  10. The origin of lunar mascons - Analysis of the Bouguer gravity associated with Grimaldi

    Science.gov (United States)

    Phillips, R. J.; Dvorak, J.

    Grimaldi is a relatively small multi-ringed basin located on the western limb of the moon. Spacecraft free-air gravity data reveal a mascon associated with the inner ring of this structure, and the topographic correction to the local lunar gravity field indicates a maximum Bouguer anomaly of +90 milligals at an altitude of 70 kilometers. Approximately 20% of this positive Bouguer anomaly can be attributed to the mare material lying within the inner ring of this basin. From a consideration of the Bouguer gravity and structure of large lunar craters comparable in size to the central basin of Grimaldi, it is suggested that the remaining positive Bouguer anomaly is due to a centrally uplifted plug of lunar mantle material. The uplift was caused by inward crustal collapse which also resulted in the formation of the concentric outer scarp of Grimaldi. In addition, an annulus of low density material, probably a combination of ejecta and in situ breccia, is required to fully reproduce the Bouguer gravity signature across this basin. It is proposed that Grimaldi supplies a critical test in the theory of mascon formation: crustal collapse by ring faulting and central uplift to depths of the crust-mantle boundary are requisites

  11. Cardiovascular autonomic adaptation in lunar and martian gravity during parabolic flight.

    Science.gov (United States)

    Widjaja, Devy; Vandeput, Steven; Van Huffel, Sabine; Aubert, André E

    2015-06-01

    Weightlessness has a well-known effect on the autonomic control of the cardiovascular system. With future missions to Mars in mind, it is important to know what the effect of partial gravity is on the human body. We aim to study the autonomic response of the cardiovascular system to partial gravity levels, as present on the Moon and on Mars, during parabolic flight. ECG and blood pressure were continuously recorded during parabolic flight. A temporal analysis of blood pressure and heart rate to changing gravity was conducted to study the dynamic response. In addition, cardiovascular autonomic control was quantified by means of heart rate (HR) and blood pressure (BP) variability measures. Zero and lunar gravity presented a biphasic cardiovascular response, while a triphasic response was noted during martian gravity. Heart rate and blood pressure are positively correlated with gravity, while the general variability of HR and BP, as well as vagal indices showed negative correlations with increasing gravity. However, the increase in vagal modulation during weightlessness is not in proportion when compared to the increase during partial gravity. Correlations were found between the gravity level and modulations in the autonomic nervous system during parabolic flight. Nevertheless, with future Mars missions in mind, more studies are needed to use these findings to develop appropriate countermeasures.

  12. Dirt, Gravity, and Lunar-Based Telescopes: The Value Proposition for Astronomy

    CERN Document Server

    Lester, D

    2007-01-01

    The lunar surface has historically been considered an optimal site for a broad range of astronomical telescopes. That assumption, which has come to be somewhat reflexive, is critically examined in this paper and found to be poorly substantiated. The value of the lunar surface for astronomy may be broadly compelling only in comparison to terrestrial sites. It is suggested here that the development and successful operation of the Hubble Space Telescope marked a turning point in the perception of value for free-space siting of astronomical telescopes, and for telescopes on the Moon. As the astronomical community considers the scientific potential of the Vision for Space Exploration (VSE) and the return to the Moon in particular, it should construct a value proposition that includes the tools, technology, and architecture being developed for this return, as these can well be seen as being more astronomically enabling than the lunar surface itself - a destination that offers little more than rocks and gravity. Whi...

  13. The Effect of Center of Gravity and Anthropometrics on Human Performance in Simulated Lunar and Mars Gravity

    Science.gov (United States)

    Mulugeta, Lealem; Chappell, Steven P.

    2009-01-01

    Drawing from the experiences of the Apollo missions, it is evident that the off nominal center of gravity (CG) induced by the portable life support system (PLSS) had significant impact on the locomotion stability of the crew. This in turn is believed to have been a major contributor to the high numbers of falls and high metabolic rates experienced by the crew, and thus significantly hampered the crew s performance. With this in mind, the EVA Physiology, Systems and Performance (EPSP) group at the NASA Johnson Space Center (JSC) has been conducting tests to assess how spacesuit CG location impacts human performance in simulated lunar and Mars gravity. The results acquired to date show correlations between CG location and performance. However, noticeable variations in the performance data have been observed across subjects for fixed CG configurations. Consequently, it was hypothesized that this variability may be attributed to the anthropometrics of the different test subjects. It was further hypothesized that trunk-to-height ratio (THR) may be directly correlated to performance in reduced gravity; i.e. subjects with increased THR may have increased performance. To test this hypothesis, lunar and Mars gravity test data acquired over three years during NASA Neural Buoyancy Lab (NBL) tests and NASA Extreme Environment Missions Operation (NEEMO) missions were analyzed against THR, height, trunk length, and subject body mass/weight. The results of the study supported the hypothesis relating THR and performance, while the other three anthropometric parameters did not provide consistent correlations with performance. This in turn suggests that human performance in reduced gravity may be more dependent on anthropometric proportions than on body segment lengths and mass/weight.

  14. The Effect of Center of Gravity and Anthropometrics on Human Performance in Simulated Lunar and Mars Gravity

    Science.gov (United States)

    Mulugeta, Lealem; Chappell, Steven P.

    2009-01-01

    Drawing from the experiences of the Apollo missions, it is evident that the off nominal center of gravity (CG) induced by the portable life support system (PLSS) had significant impact on the locomotion stability of the crew. This in turn is believed to have been a major contributor to the high numbers of falls and high metabolic rates experienced by the crew, and thus significantly hampered the crew s performance. With this in mind, the EVA Physiology, Systems and Performance (EPSP) group at the NASA Johnson Space Center (JSC) has been conducting tests to assess how spacesuit CG location impacts human performance in simulated lunar and Mars gravity. The results acquired to date show correlations between CG location and performance. However, noticeable variations in the performance data have been observed across subjects for fixed CG configurations. Consequently, it was hypothesized that this variability may be attributed to the anthropometrics of the different test subjects. It was further hypothesized that trunk-to-height ratio (THR) may be directly correlated to performance in reduced gravity; i.e. subjects with increased THR may have increased performance. To test this hypothesis, lunar and Mars gravity test data acquired over three years during NASA Neural Buoyancy Lab (NBL) tests and NASA Extreme Environment Missions Operation (NEEMO) missions were analyzed against THR, height, trunk length, and subject body mass/weight. The results of the study supported the hypothesis relating THR and performance, while the other three anthropometric parameters did not provide consistent correlations with performance. This in turn suggests that human performance in reduced gravity may be more dependent on anthropometric proportions than on body segment lengths and mass/weight.

  15. The Effect of Center of Gravity and Anthropometrics on Human Performance in Simulated Lunar Gravity

    Science.gov (United States)

    Mulugeta, Lealem; Chappell, Steven P.; Skytland, Nicholas G.

    2009-01-01

    NASA EVA Physiology, Systems and Performance (EPSP) Project at JSC has been investigating the effects of Center of Gravity and other factors on astronaut performance in reduced gravity. A subset of the studies have been performed with the water immersion technique. Study results show correlation between Center of Gravity location and performance. However, data variability observed between subjects for prescribed Center of Gravity configurations. The hypothesis is that Anthropometric differences between test subjects could be a source of the performance variability.

  16. Effect of Changing the Center of Gravity on Human Performance in Simulated Lunar Gravity

    Science.gov (United States)

    Chappell, Steven P.; Norcross, Jason R.; Gernhardt, Michael L.

    2010-01-01

    The presentation slides include: Moving Past Apollo, Testing in Analog Environments, NEEMO/NBL CG (center of gravity) Studies, Center of Gravity Test Design and Methods, CG Suited Locations and Results, CG Individual Considerations, CG Shirt-Sleeve Locations and Results.

  17. Propagating Degrees of Freedom in f(R Gravity

    Directory of Open Access Journals (Sweden)

    Yun Soo Myung

    2016-01-01

    Full Text Available We have computed the number of polarization modes of gravitational waves propagating in the Minkowski background in f(R gravity. These are three of two from transverse-traceless tensor modes and one from a massive trace mode, which confirms the results found in the literature. There is no massless breathing mode and the massive trace mode corresponds to the Ricci scalar. A newly defined metric tensor in f(R gravity satisfies the transverse-traceless (TT condition as well as the TT wave equation.

  18. Propagating degrees of freedom in f(R) gravity

    CERN Document Server

    Myung, Yun Soo

    2016-01-01

    We have computed the number of polarization modes of gravitational waves propagating in the Minkowski background in f(R) gravity. This is three of two from transverse-traceless tensor modes and one from a massive trace mode, which confirms the results found in the literature. There is no massless breathing mode and the massive trace mode corresponds to the Ricci scalar. A newly defined metric tensor satisfies the transverse-traceless (TT) condition as well as the TT wave equation.

  19. Development of a Gravity-Insensitive Heat Pump for Lunar Applications

    Science.gov (United States)

    Cole, Gregory S.; Scaringe, Robert P.; Grzyll, Lawrence R.; Ewert, Michael K.

    2006-01-01

    Mainstream Engineering Corporation is developing a gravity-insensitive system that will allow a vapor-compression-cycle heat pump to be used in both microgravity (10(exp -6)g) and lunar (10(exp -6)g) environments. System capacity is 5 kW to 15 kW at design refrigerant operating conditions of 4.44 C and 60 C evaporating and condensing temperatures, respectively. The current program, performed for NASA Johnson Space Center (JSC) and presented in this paper, includes compressor performance analysis, detailed system design, and thermal analysis. Future efforts, including prototype fabrication, integration of a solar power source and controls, ground-testing, and flight-testing support, are also discussed.

  20. Discussions on the Study of Lunar Gravity Field%月球重力场研究的论述

    Institute of Scientific and Technical Information of China (English)

    杨宏伟; 赵文津; 吴珍汉

    2011-01-01

    月球重力场探测是了解月球内部结构构造最有效的手段之一,也是未来登陆点选择的重要依据.在众多方法中,卫星重力探测是进行全月球覆盖以及获得月球深部信息的重要方法.本文叙述了当前月球重力探测历史和重力模型发展过程,并对这些模型进行比较分析.在了解前沿研究方法的基础上讨论了月球重力位场解算的基本原理、高精度月球重力场获得的方法和各种月球重力归算方法,以及当前国际上利用月球重力场研究其内部结构构造的热点问题.最后对月球的典型重力异常特征进行了综合性的分析.%Lunar gravimetry is one of the most useful approaches to understanding the interior constitution and structure of the moon and also serves as a fundamental basis for choice of landing sites in future. Of varied methods, satellite gravimetry is an important means for covering the whole moon and obtaining deep information.This paper has described the history of lunar gravity exploration and the development of lunar gravity models, and analyzed and comparatively studied these models. Based on knowledge of forefront research methods, the authors deal with the principle for solution of lunar gravity coefficient model, approaches to acquiring lunar gravity model with high accuracy, varied tools for gravity field reductions, and current heated topics in the study of the interior structure of the moon. In addition, characteristics of typical gravity anomalies in the moon are comprehensively analyzed.

  1. Cosmological dynamics of $f(R)$ gravity scalar degree of freedom in Einstein frame

    CERN Document Server

    Goswami, Umananda Dev

    2013-01-01

    $f(R)$ gravity models belong to an important class of modified gravity models where the late time cosmic accelerated expansion is considered as the manifestation of the large scale modification of the force of gravity. $f(R)$ gravity models can be expressed in terms of a scalar degree of freedom by redefinition of models variable. The conformal transformation of the action from Jordan frame to Einstein frame makes the scalar degree of freedom more explicit and can be studied conveniently. We have investigated the features of the scalar degree of freedoms and the consequent cosmological implications of the power-law ($\\xi R^n$) and the Starobinsky (disappearing cosmological constant) $f(R)$ gravity models numerically in the Einstein frame. Both the models show interesting behaviour of their scalar degree of freedom and could produce the accelerated expansion of the Universe in the Einstein frame with the negative equation of state of the scalar field. However the scalar field potential for the power-law model ...

  2. Study of lunar gravity assist orbits in the restricted four-body problem

    Science.gov (United States)

    Qi, Yi; Xu, Shijie

    2016-07-01

    In this paper, the lunar gravity assist (LGA) orbits starting from the Earth are investigated in the Sun-Earth-Moon-spacecraft restricted four-body problem (RFBP). First of all, the sphere of influence of the Earth-Moon system (SOIEM) is derived. Numerical calculation displays that inside the SOIEM, the effect of the Sun on the LGA orbits is quite small, but outside the SOIEM, the Sun perturbation can remarkably influence the trend of the LGA orbit. To analyze the effect of the Sun, the RFBP outside the SOIEM is approximately replaced by a planar circular restricted three-body problem, where, in the latter case, the Sun and the Earth-Moon barycenter act as primaries. The stable manifolds associated with the libration point orbit and their Poincaré sections on the SOIEM are applied to investigating the LGA orbit. According to our research, the patched LGA orbits on the Poincaré sections can efficiently distinguish the transit LGA orbits from the non-transit LGA orbits under the RFBP. The former orbits can pass through the region around libration point away from the SOIEM, but the latter orbits will bounce back to the SOIEM. Besides, the stable transit probability is defined and analyzed. According to the variant requirement of the space mission, the results obtained can help us select the LGA orbit and the launch window.

  3. 月球重力场环境对月球卫星轨道影响分析%The effect of lunar gravity environment on lunar satellite orbit

    Institute of Scientific and Technical Information of China (English)

    童科伟; 李文清; 刘伟; 高朝辉; 王俊峰

    2012-01-01

    文章分析了月球复杂的重力场环境对月球卫星轨道运行的影响。通过月球卫星冻结轨道与地球卫星冻结轨道的对比分析,结果表明月球重力场存在较大异常,并由此引起月球卫星轨道发生较大漂移。另外,月球冻结轨道在带谐项影响下还存在中等周期的漂移,仅简单考虑带谐项系数无法求得完美的月球冻结系数。由于月球重力场异常对绕月卫星的影响与地球轨道卫星情况相比存在很大差异,因此月球轨道卫星的长期运行与控制策略的设计必须充分考虑此影响%The effect of lunar gravity environment on the lunar satellite orbit is analyzed. The differences between the frozen orbit for lunar and earth satellites are compared first. It is shown that the lunar gravity anomaly is responsible for a large drift to the lunar satellite orbit, the lunar tesseral harmonics are responsible for a moderate period drift to the lunar frozen orbit. Because the effect of lunar gravity anomaly on lunar satellites is quite different from the case for the earth, so for the long-term orbit operation and control for lunar satellites, a different strategy must be adopted than the traditional methods designed for the earth satellite orbit.

  4. Geologic significance of new isostatic gravity and aeromagnetic maps of the Winnemucca 1[degree] by 2[degree] quadrangle, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, H.W.; Sikora, R.F. (Geological Survey, Menlo Park, CA (United States)); Robbins, S.L. (Geological Survey, Denver, CO (United States))

    1993-04-01

    Since Wagini's 1986 Bouguer and isostatic gravity compilations of the Winnemucca 1[degree] by 2[degree] quadrangle, R. Sikora has provided an 1991 update that includes 133 new stations obtained in the Sonoma Range, Boulder Valley, and the Battle Mountain areas. Since that 1991 update, 371 additional stations have been obtained by S. Robbins in the Pine and Crescent Valley areas to look for possible gravity signatures of petroleum and gold deposits. All these data have been reduced and incorporated into a new isostatic gravity map of the quadrangle. This new compilation shows that the largest residual low of 32 mGal occurs over petroleum-bearing Pine Valley, although nearly-as-large gravity lows (27--31 mGal) occur over Buena Vista, Pleasant, Reese River, and Grass Valleys. A new aeromagnetic compilation of the Winnemucca quadrangle is continued downward to 300 m above terrain and shows a number of magnetic highs associated with igneous rocks, both intrusive and extrusive. A nearly continuous north-northwest trending magnetic high of about 400 nT, known as the northern Nevada rift, cuts across the quadrangle about 10 km east of Battle Mountain and is associated at some locations with Miocene basaltic and andesitic extrusive rocks. Three Miocene epithermal gold deposits are associated with this magnetic high at Mule Canyon, Fire Creek, and Bluckhorn. A smaller but broader magnetic high of about 200 nT at 300 m above terrain is located over the Tuscarora Mountains about 15 km northwest of Carlin. The maximum horizontal gradient of the pseudogravity transformation of the total magnetic field coincides with a series of ten productive gold mines known as the Carlin trend.

  5. Study of Electro-Cyclonic Filtration and Pneumatic Transfer of Lunar Regolith Simulants under 1/6-g and 1-g Gravity Conditions

    Science.gov (United States)

    Mantovani, James G.; Townsend, Ivan I.; Mueller, Robert P.

    2009-01-01

    NASA has built a prototype oxygen production plant to process the lunar regolith using the hydrogen reduction chemical process. This plant is known as "ROxygen - making oxygen from moon rocks". The ROxygen regolith transfer team has identified the flow and transfer characteristics of lunar regolith simulant to be a concern for lunar oxygen production efforts. It is important to ISRU lunar exploration efforts to develop hardware designs that can demonstrate the ability to flow and transfer a given mass of regolith simulant to a desired vertical height under lunar gravity conditions in order to introduce it into a reactor. We will present results obtained under both 1/6-g and 1-g gravity conditions for a system that can pneumatically convey 16.5 kg of lunar regolith simulant (NU-LHT-2M, Mauna Kea Tephra, and JSC-1A) from a flat-bottom supply hopper to a simulated ISRU reactor (dual-chambered receiving hopper) where the granular material is separated from the convey gas (air) using a series of cyclone separators, one of which is an electrically enhanced cyclone separator (electrocyclone). The results of our study include (1) the mass flow rate as a function of input air pressure for lunar regolith simulants that are conveyed pneumatically as a dusty gas in a vertical direction against gravity under lunar gravity conditions (for NU-LHT-2M and Mauna Kea Tephra), and under earth gravity conditions (for NU-LHT-2M, Mauna Kea Tephra and JSC-1A), and (2) the efficiency of the cyclone/electrocyclone filtration system in separating the convey gas (air) from the granular particulates as a function of particle size.

  6. High degree gravitational sensitivity from Mars orbiters for the GMM-1 gravity model

    Science.gov (United States)

    Lerch, F. J.; Smith, D. E.; Chan, J. C.; Patel, G. B.; Chinn, D. S.

    1994-01-01

    Orbital sensitivity of the gravity field for high degree terms (greater than 30) is analyzed on satellites employed in a Goddard Mars Model GMM-1, complete in spherical harmonics through degree and order 50. The model is obtained from S-band Doppler data on Mariner 9 (M9), Viking Orbiter 1 (VO1), and Viking Orbiter 2 (VO2) spacecraft, which were tracked by the NASA Deep Space Network on seven different highly eccentric orbits. The main sensitivity of the high degree terms is obtained from the VO1 and VO2 low orbits (300 km periapsis altitude), where significant spectral sensitivity is seen for all degrees out through degree 50. The velocity perturbations show a dominant effect at periapsis and significant effects out beyond the semi-latus rectum covering over 180 degrees of the orbital groundtrack for the low altitude orbits. Because of the wideband of periapsis motion covering nearly 180 degrees in w and +39 degrees in latitude coverage, the VO1 300 km periapsis altitude orbit with inclination of 39 degrees gave the dominant sensitivity in the GMM-1 solution for the high degree terms. Although the VO2 low periapsis orbit has a smaller band of periapsis mapping coverage, it strongly complements the VO1 orbit sensitivity for the GMM-1 solution with Doppler tracking coverage over a different inclination of 80 degrees.

  7. High precision gravity analysis and hydrological modeling from the Lunar Laser Ranging Observatory at Apache Point, New Mexico

    Science.gov (United States)

    Liang, Jiahao

    The NASA-supported Lunar Laser Ranging project (LLR) is located at Apache Point, New Mexico, which strives to precisely measure the orbital distance between the Earth and the Moon in an accuracy of a few millimeters. To archive this objective, LLR project requires precise data on local ground deformation, which is difficult to measure directly. However, the high precision gravity data is the reflection of vertical ground deformation of the Earth, therefore the gravity data is able to contribute to the LLR project. Gravity time series is affected by Earth tides, atmospheric pressure, polar motion, and the most critical effect, local hydrology. In order to isolate pure geodetic variation, these effects must be removed from the data. Thus, the goal of this research is to create models of above effects, especially local hydrology model, in order to isolate the vertical deformation signal. The Earth tides, atmospheric pressure and polar motion effects have been modeled and subtracted from gravity data (2009~2012). The local hydrological model has been created based on the in-situ data, which are rainfall, snowfall and temperature. The correlation coefficient and RMS misfit between the hydrological model and gravity residual (2010~2012) is 0.92 and 1.26 microGal. The instrument drift corrections in 2009 have been reanalyzed after comparing with some global hydrological models. The gravity residual from new corrections showed a correlation coefficient of 0.76 and RMS misfit of 1.25 microGal. The isolated deformation signal was obtained after we subtracted the hydrological effects, and the results can be used for further modeling.

  8. Behaviour of the low degree terms of the Earth gravity field over the last 30 years

    Science.gov (United States)

    Biancale, R.; Lemoine, J.-M.; Reinquin, F.; Deleflie, F.; Ramillien, G.; Gégout, P.

    2012-04-01

    The GRACE mission has revealed since 2002 the recent evolution of the Earth's gravity field with a resolution down to 400 km, equivalent to degree and order 50 in spherical harmonics. Precise orbit computation for altimetric satellites can obviously gain by applying these variations, which are classically given, as in recent EIGEN models, as drifts and periodic terms (yearly and semi-yearly). However extrapolating these variations to pre-GRACE periods, mainly the drifts, can be problematic for orbit computation performances on former altimetric satellites. One option is to analyse older satellite data, in particular SLR data on geodetic satellites, in order to assess the very low degree variations of the gravity field and compare it to the GRACE determination. This can be done over the last 30 years, using for instance the Lageos and Lageos-2, Starlette and Stella satellites. The spherical harmonic degrees that can be accessed in this way are degrees 2 to 4. Additional information on degree 2 can be derived from the analysis of the Earth orientation parameters, pole coordinates and length of day (LOD), which have been observed over a long period with great accuracy by astrometric, satellite geodetic and extra-galactic means. Once corrected for atmospheric and oceanic load and velocity variations, the pole coordinates will principally bring information on the C(2,1) and S(2,1) coefficients, while the LOD will principally be connected with the C(2,0). Combining these two approaches allows a better observation of the temporal evolution of the gravity field over a long time span and a more realistic modelling of it for the precise orbit computation of past altimeter missions.

  9. Analysis of the Lunar Gravity Field by Using GL0660B Model and Its Effect on Lunar Satellite Orbit%月球重力场模型GL0660B特征分析及其对绕月卫星轨道的影响

    Institute of Scientific and Technical Information of China (English)

    黄昆学; 常晓涛; 朱广彬; 李武东

    2016-01-01

    The lunar gravity field provides a way to research moon’s evolution and probes the interior structure of the moon.It is an important factor influencing the lunar satellite precise orbit determination as well.The new lunar gravity model GL0660B from GRAIL mission dramatically improves the gravity spectrum and spectral ranges.Using the model GL0660B,it can be computed that the corresponding degree-wise RMS and correlation of topography,with which the quality of model GL0660B can be analyzed.Then different characters of the lunar gravity field comparing with other lunar gravity fields are analyzed. Besides,gravity anomaly distribution figures at different height of the models are given,and the character and difference of the lunar gravity models at different height are compared.In addition,lunar satellite orbit revolutionary at different height are modeled by GEODYN.The result shows that the trend of lunar satellite eccentricity changes is a complex and long cycle of change trend.It is different affected by the perturbation of the mascons of different height,which causes different changes of apolune,perilune and eccentricity.%月球重力场可用来研究月球演化过程和内部结构,是影响绕月卫星精密定轨的重要因素。基于GRAIL任务数据解算的GL0660B重力场模型,极大提高了月球重力场空间频谱信号的强度和范围。本文首先通过计算相应重力场的阶方差和地形相关性分析,对GL0660B模型进行了精度分析;其次,利用GL0660B模型和其他几个月球重力场模型进行比较,对月球重力场的特征进行了分析;然后通过绘制GL0660B模型和 LP150Q模型在月球外部不同高度处的重力异常图,分析比较了月球重力场模型在不同高度上所反映的月球重力场的特征和差异;最后,利用 GEODYN 软件模拟计算了不同高度卫星的轨道变化。可以看出绕月卫星离心率随时间的变化,以及周期性变化趋势,而且

  10. 月球探测器LP精密定轨及月球重力场模型解算%Precision Orbit Determination of Lunar Spacecraft LP and Lunar Gravity Field Model Solution

    Institute of Scientific and Technical Information of China (English)

    鄢建国; 李斐; 平劲松

    2011-01-01

    对美国1998年发射的月球探测器LP任务阶段共19个月的双程测距测速轨道跟踪数据进行了精密定轨,对定轨结果通过轨道残差及重复弧段差异进行了精度评价.利用LP正常任务阶段三个月的轨道跟踪数据进行了月球重力场模型解算,通过重力场功率谱、轨道残差和月球自由空气重力异常对解算模型进行了精度评价.结果表明精密定轨及月球重力场模型解算合理.对进一步融合嫦娥一号轨道跟踪数据和LP数据解算自主的高精度月球重力场模型具有参考意义.%Two-way range and Doppler data in 19 months are used for precision orhit determination of lunar exploration mission LP. The orbit determination accuracy is assessed by orbit residuals and orbit overlap differences. The lunar gravity field model is solved based on 3 months tracking data of LP during nominal phase, and the model accuracy is evaluated by gravity field power spectrum , orbit residuals and lunar free-air gravity anomaly. Results show the reasonability of precision orbit determination and lunar gravity field solution. The work would provide a reference for independent high accuracy lunar gravity field model solution by combining orbit track data of Chang' E-1 and LP.

  11. Secular Motion in a 2nd Degree and Order-Gravity Field with no Rotation

    Science.gov (United States)

    Scheeres, D. J.; Hu, W.

    2001-03-01

    The motion of a particle about a non-rotating 2nd degree and order-gravity field is investigated. Averaging conditions are applied to the particle motion and a qualitative analysis which reveals the general character of motion in this system is given. It is shown that the orbit plane will either be stationary or precess about the body's axis of minimum or maximum moment of inertia. It is also shown that the secular equations for this system can be integrated in terms of trigonometric, hyperbolic or elliptic functions. The explicit solutions are derived in all cases of interest.

  12. The Effect of Pre-Impact Porosity and Vertical Density Gradients on the Gravity Signature of Lunar Craters

    Science.gov (United States)

    Milbury, Colleen; Johnson, Brandon C.; Melosh, H. Jay; Collins, Gareth S.; Blair, David M.; Soderblom, Jason M.; Nimmo, Francis; Phillips, Roger J.; Bierson, Carver J.; Zuber, Maria T.

    2015-11-01

    As a result of NASA’s dual spacecraft Gravity Recovery And Interior Laboratory (GRAIL) mission [Zuber et al., 2013; doi:10.1126/science.1231507], we now know that the lunar crust is highly porous and that the porosity varies laterally [Wieczorek et al., 2013; doi:10.1126/science.1231530] and vertically [Besserer et al., 2014; doi:10.1002/2014GL060240]. Analysis of complex craters located within the lunar highlands reveals that: 1) craters larger than diameter D~210 have positive Bouguer Anomalies (BAs), 2) craters with D ≲ 100 km have both positive and negative BAs that vary about the (near 0) mean by approximately ± 25 mGal, and, 3) D and BA are anticorrelated for craters with D ≲ 100 km [Soderblom et al., 2015; doi:10.1002/2015GL065022]. Numerical modeling by Milbury et al. [2015, LPSC] shows that pre-impact porosity is the dominant influence on the gravity signature of complex craters with D ≲ 100 km, and mantle uplift dominates the gravity for those with D > 140 km. Phillips et al. [2015, LPSC] showed that complex craters located in the South Pole-Aitken (SPA) basin tend to have more-negative BAs than similar craters in the highlands. We use the iSALE hydrocode including pore space compaction [Wünnemann et al., 2006; doi:10.1016/j.icarus.2005.10.013] and dilatant bulking [Collins, 2014; doi:10.1002/2014JE004708] to understand how the gravity signature of impact craters develop. In this study we vary crustal porosity with depth. We find that simulations that have constant porosity with depth have a lower BA for a given crater diameter than those with the same mean porosity, but that vary with depth. We used two different mean porosities (7% and 14%) and found that the BA increases with increasing porosity, similar to simulations with constant porosity. We reproduce the observed anticorrelation between BA and D for D ≲ 100 km only for simulations where the pre-impact porosity is zero or low. Our results support the observation that SPA has lower

  13. Effect of Simulated Microgravity and Lunar Gravity on Human Inspiratory Muscle Function: 'Selena-T' 2015 Study.

    Science.gov (United States)

    Segizbaeva, M O; Aleksandrova, N P; Donina, Z A; Baranova, E V; Katuntsev, V P; Tarasenkov, G G; Baranov, V M

    2016-01-01

    As a part of the multi-disciplinary "SELENA-T"-2015 Bed Rest Study, we investigated the pattern of inspiratory muscles fatigue in 22 healthy male subjects during incremental exercise test to exhaustion before and after 21 days of hypokinesia evoked by bed rest. Hypokinesia consisted of head-down bed rest (HDBR) at a minus 6° angle, simulating microgravity present on orbiting spacecraft, in 10 subjects. The remaining 12 subjects spent the first 5 days of hypokinesia in HDBR position and the subsequent 16 days in head-up bed rest (HUBR) at a plus 9.6° angle, as a presumed analog of lunar gravity that is six times less than Earth's gravity. Maximal inspiratory pressure (MIP) and electromyograms (EMG) of the diaphragm (D), parasternal (PS), sternocleidomastoid (SCM), and scalene (S) muscles served as indices of inspiratory muscle function. Before both HDBR and HUBR, exercise decreased MIP and centroid frequency (fc) of EMG (D, PS, SCM, and S) power spectrum (p effect. These changes may limit maximal ventilation and may contribute to exercise intolerance observed after prolonged simulated microgravity. The physiological mechanisms of respiratory muscle dysfunction after HDBR consist primarily of postural effects, and are not due only to hypokinesia.

  14. Testing gravity with Lunar Laser Ranging: An update on the APOLLO experiment

    Science.gov (United States)

    Battat, James; Colmenares, Nick; Davis, Rodney; Ruixue, Louisa Huang; Murphy, Thomas W., Jr.; Apollo Collaboration

    2017-01-01

    The mystery of dark energy and the incompatibility of quantum mechanics and General Relativity indicate the need for precision experimental probes of gravitational physics. The Earth-Moon-Sun system is a fertile laboratory for such tests. The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) makes optical range measurements to retro-reflectors on the Moon with one millimeter precision. These measurements of the lunar orbit enable incisive constraints on gravitational phenomena such as the Strong Equivalence Principle and dG / dt (among others). Until now, the APOLLO team had not been able to assess the accuracy of our data, in large part because known limitations to lunar range models ensure data-model residuals at the centimeter scale. To directly measure the APOLLO system timing accuracy, we have built an Absolute timing Calibration System (ACS) that delivers photons to our detector at known, stable time intervals using a pulsed fiber laser locked to a cesium frequency standard. This scheme provides real-time calibration of the APOLLO system timing, synchronous with the range measurements. We installed the calibration system in August, 2016. In this talk, we will describe the ACS design, and present present preliminary results from the ACS calibration campaign. We acknowledge the support of both NSF and NASA

  15. Lunar gravitational field estimation and the effects of mismodeling upon lunar satellite orbit prediction. M.S. Thesis

    Science.gov (United States)

    Davis, John H.

    1993-01-01

    Lunar spherical harmonic gravity coefficients are estimated from simulated observations of a near-circular low altitude polar orbiter disturbed by lunar mascons. Lunar gravity sensing missions using earth-based nearside observations with and without satellite-based far-side observations are simulated and least squares maximum likelihood estimates are developed for spherical harmonic expansion fit models. Simulations and parameter estimations are performed by a modified version of the Smithsonian Astrophysical Observatory's Planetary Ephemeris Program. Two different lunar spacecraft mission phases are simulated to evaluate the estimated fit models. Results for predicting state covariances one orbit ahead are presented along with the state errors resulting from the mismodeled gravity field. The position errors from planning a lunar landing maneuver with a mismodeled gravity field are also presented. These simulations clearly demonstrate the need to include observations of satellite motion over the far side in estimating the lunar gravity field. The simulations also illustrate that the eighth degree and order expansions used in the simulated fits were unable to adequately model lunar mascons.

  16. Structural Design and Simulation of Passive Low Gravity Compensation for the Deployable Arm in the Device of Drilling and Collecting Lunar Soil

    Directory of Open Access Journals (Sweden)

    Tao Jianguo

    2015-01-01

    Full Text Available As an important constituent part of the sampling device for lunar soil drilling, the deployable arm can help transfer the samples and avoid stretching. According to the ground experimental research requirements for deployable arm, this paper proposed a low-gravity compensation method of passive cam counter weight by establishing a Lagrangian dynamics model of deployable arm. It is emphasized on designing the profile curve of cam mechanism and the mechanical structure of cam component. By using ADAMS software, this paper conducted kinematics analogue simulation and obtained the kinematic parameters of deployable arm under the environmental conditions of the lunar surface and of the ground surface. The comparison of the analogue results has verified the necessity and reasonability of this compensation method. At last, this paper reached the conclusions and proposed measures to improve the compensation device. This paper can offer certain technical reference for the ground experiment of the sampling mechanism used for lunar drilling and the engineering implementation.

  17. Structural Design and Simulation of Passive Low Gravity Compensation for the Deployable Arm in the Device of Drilling and Collecting Lunar Soil

    OpenAIRE

    Tao Jianguo; Wang Guoxing; Li Jianyong

    2015-01-01

    As an important constituent part of the sampling device for lunar soil drilling, the deployable arm can help transfer the samples and avoid stretching. According to the ground experimental research requirements for deployable arm, this paper proposed a low-gravity compensation method of passive cam counter weight by establishing a Lagrangian dynamics model of deployable arm. It is emphasized on designing the profile curve of cam mechanism and the mechanical structure of cam component. By usin...

  18. A new degree-2190 (10 km resolution) gravity field model for Antarctica developed from GRACE, GOCE and Bedmap2 data

    Science.gov (United States)

    Hirt, Christian; Rexer, Moritz; Scheinert, Mirko; Pail, Roland; Claessens, Sten; Holmes, Simon

    2016-02-01

    The current high-degree global geopotential models EGM2008 and EIGEN-6C4 resolve gravity field structures to ˜ 10 km spatial scales over most parts of the of Earth's surface. However, a notable exception is continental Antarctica, where the gravity information in these and other recent models is based on satellite gravimetry observations only, and thus limited to about ˜ 80-120 km spatial scales. Here, we present a new degree-2190 global gravity model (GGM) that for the first time improves the spatial resolution of the gravity field over the whole of continental Antarctica to ˜ 10 km spatial scales. The new model called SatGravRET2014 is a combination of recent Gravity Recovery and Climate Experiment (GRACE) and Gravity field and steady-state Ocean Circulation Explorer (GOCE) satellite gravimetry with gravitational signals derived from the 2013 Bedmap2 topography/ice thickness/bedrock model with gravity forward modelling in ellipsoidal approximation. Bedmap2 is a significantly improved description of the topographic mass distribution over the Antarctic region based on a multitude of topographic surveys, and a well-suited source for modelling short-scale gravity signals as we show in our study. We describe the development of SatGravRET2014 which entirely relies on spherical harmonic modelling techniques. Details are provided on the least-squares combination procedures and on the conversion of topography to implied gravitational potential. The main outcome of our work is the SatGravRET2014 spherical harmonic series expansion to degree 2190, and derived high-resolution grids of 3D-synthesized gravity and quasigeoid effects over the whole of Antarctica. For validation, six data sets from the IAG Subcommission 2.4f "Gravity and Geoid in Antarctica" (AntGG) database were used comprising a total of 1,092,981 airborne gravimetric observations. All subsets consistently show that the Bedmap2-based short-scale gravity modelling improves the agreement over satellite

  19. Structure and Evolution of the Lunar Procellarum Region as Revealed by GRAIL Gravity Data

    Science.gov (United States)

    Andrews-Hanna, Jeffrey C.; Besserer, Jonathan; Head, James W., III; Howett, Carly J. A.; Kiefer, Walter S.; Lucey, Paul J.; McGovern, Patrick J.; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Schenk, Paul M.; Smith, David E.; Solomon, Sean C.; Zuber, Maria T.

    2014-01-01

    The Procellarum region is a broad area on the nearside of the Moon that is characterized by low elevations, thin crust, and high surface concentrations of the heat-producing elements uranium, thorium, and potassium. The Procellarum region has been interpreted as an ancient impact basin approximately 3200 km in diameter, though supporting evidence at the surface would have been largely obscured as a result of the great antiquity and poor preservation of any diagnostic features. Here we use data from the Gravity Recovery and Interior Laboratory (GRAIL) mission to examine the subsurface structure of Procellarum. The Bouguer gravity anomalies and gravity gradients reveal a pattern of narrow linear anomalies that border the Procellarum region and are interpreted to be the frozen remnants of lava-filled rifts and the underlying feeder dikes that served as the magma plumbing system for much of the nearside mare volcanism. The discontinuous surface structures that were earlier interpreted as remnants of an impact basin rim are shown in GRAIL data to be a part of this continuous set of quasi-rectangular border structures with angular intersections, contrary to the expected circular or elliptical shape of an impact basin. The spatial pattern of magmatic-tectonic structures bounding Procellarum is consistent with their formation in response to thermal stresses produced by the differential cooling of the province relative to its surroundings, coupled with magmatic activity driven by the elevated heat flux in the region.

  20. Use of a Lunar Outpost for Developing Space Settlement Technologies

    Science.gov (United States)

    Purves, Lloyd R.

    2008-01-01

    The type of polar lunar outpost being considered in the NASA Vision for Space Exploration (VSE) can effectively support the development of technologies that will not only significantly enhance lunar exploration, but also enable long term crewed space missions, including space settlement. The critical technologies are: artificial gravity, radiation protection, Closed Ecological Life Support Systems (CELSS) and In-Situ Resource Utilization (ISRU). These enhance lunar exploration by extending the time an astronaut can remain on the moon and reducing the need for supplies from Earth, and they seem required for space settlement. A polar lunar outpost provides a location to perform the research and testing required to develop these technologies, as well as to determine if there are viable countermeasures that can reduce the need for Earth-surface-equivalent gravity and radiation protection on long human space missions. The types of spinning space vehicles or stations envisioned to provide artificial gravity can be implemented and tested on the lunar surface, where they can create any level of effective gravity above the 1/6 Earth gravity that naturally exists on the lunar surface. Likewise, varying degrees of radiation protection can provide a natural radiation environment on the lunar surface less than or equal to 1/2 that of open space at 1 AU. Lunar ISRU has the potential of providing most of the material needed for radiation protection, the centrifuge that provides artificial gravity; and the atmosphere, water and soil for a CELSS. Lunar ISRU both saves the cost of transporting these materials from Earth and helps define the requirements for ISRU on other planetary bodies. Biosphere II provides a reference point for estimating what is required for an initial habitat with a CELSS. Previous studies provide initial estimates of what would be required to provide such a lunar habitat with the gravity and radiation environment of the Earth s surface. While much preparatory

  1. Torsion, a multivalued gauge degree of freedom in Einstein's gravity

    Energy Technology Data Exchange (ETDEWEB)

    Kleinert, H, E-mail: h.k@fu-berlin.de [Institut fuer Theoretische Physik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin (Germany); ICRANet, Piazzale della Republica 10, 1-65122, Pescara (Italy)

    2011-07-08

    We show that there is an entire gauge symmetry of a novel kind which interpolates between an infinity of formulations of the laws of gravity, ranging from Einsteins pure curvature formulation to a pure torsion formulation in a teleparallel geometry. As a consequence, torsion and curvature are not independent and that torsion is an alternative description of curvature in gravity.

  2. Gravity field models derived from the second degree radial derivatives of the GOCE mission: a case study

    Directory of Open Access Journals (Sweden)

    Alexander N. Marchenko

    2017-01-01

    Full Text Available The GOCE satellite mission is one of the main achievements of the satellite geodesy for the Earth’s gravitational field recovery. Three different approaches have been developed for the estimation of harmonic coefficients from gradiometry data measured on board of GOCE-satellite. In this paper a special version of the space-wise method based on the second method of Neumann for fast determination of the harmonic coefficients Cnm, Snm of the Earth’s gravitational potential is given based on the radial gravity gradients of the EGG_TRF_2 product, except of two polar gaps filled by radial gradients from the EGM2008 gravity model. In the pre-processing stage GOCE-based second degree radial derivatives were averaged to the regular grid through Kalman static filter with additional Gaussean smoothing of residual radial derivatives. All computations are made by iterations. As the first step the determination of the preliminary NULP-01S model up to degree/order 220 derived from the Gaussean grid of the GOCE radial derivatives with respect to the WGS-84 reference field was developed based only one of the radial gradients EGG_TRF_2 in the EFRF-frame. In the second iteration the same algorithm is applied to build the NULP-02S gravity field model up to degree/order 250 using the same Gaussean grid with respect to the NULP-01S reference field. The NULP-02S model was verified by means of applying various approaches for the construction of the gridded gravity anomalies and geoid heights in the Black sea area using processing of datasets from six altimetry satellite missions. Comparison of different models with GNSS-levelling data in the USA area demonstrates the independent verification of achieved accuracy of the constructed NULP-02S Earth’s gravity field model.

  3. Gravity Data for the Vernal, Utah Quad.(1x2 degree)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (4,778 records) were gathered by various governmental organizations (and academia) using a variety of methods. This data base was received...

  4. Beyond the growth rate of cosmic structure: Testing modified gravity models with an extra degree of freedom

    CERN Document Server

    Burrage, Clare; Seery, David

    2015-01-01

    In 'modified' gravity the observed acceleration of the universe is explained by changing the gravitational force law or the number of degrees of freedom in the gravitational sector. Both possibilities can be tested by measurements of cosmological structure formation. In this paper we elaborate the details of such tests using the Galileon model as a case study. We pay attention to the possibility that each new degree of freedom may have stochastically independent initial conditions, generating different types of potential well in the early universe and breaking complete correlation between density and velocity power spectra. This 'stochastic bias' can confuse schemes to parametrize the predictions of modified gravity models, such as the use of the growth parameter f alone. Using data from the WiggleZ Dark Energy Survey we show that it will be possible to obtain constraints using information about the cosmological-scale force law embedded in the multipole power spectra of redshift-space distortions. As an examp...

  5. Multibeam bathymetric, gravity and magnetic studies over 79 degrees E fracture zone, central Indian basin

    Digital Repository Service at National Institute of Oceanography (India)

    KameshRaju, K.A.; Ramprasad, T.; Kodagali, V.N.; Nair, R.R.

    A regional scale bathymetric map has been constructed for the 79 degrees E fracture zone (FZ) in the Central Indian Basin between 10 degrees 15'S and 14 degrees 45'S lat. and 78 degrees 55'E and 79 degrees 20'E long. using the high...

  6. An improved lunar moment of inertia determination - A proposed strategy

    Science.gov (United States)

    Ananda, M. P.; Ferrari, A. J.; Sjogren, W. L.

    1977-01-01

    A strategy for determining an improved lunar moment of inertia is proposed. An improved uncertainty in the lunar inhomogeneity parameter could reduce the core density error from 4.20 gr/cu cm to 0.1 gm/cu cm for the case of a lunar density model having a 300 km core radius. The current error of 0.0025 for the lunar inhomogeneity parameter is mostly due to the uncertainties in the C20 and C22 gravity harmonics. An optimum reduction strategy for obtaining an order of magnitude improvement in the gravity estimates is based on covariance analyses of Doppler data. The long-arc reduction method is shown to provide better results than the short-arc technique, and the use of an orbit with a 7000 km semimajor axis along with certain terms of up to degree and order eight is recommended.

  7. Gravity

    CERN Document Server

    Gamow, George

    2003-01-01

    A distinguished physicist and teacher, George Gamow also possessed a special gift for making the intricacies of science accessible to a wide audience. In Gravity, he takes an enlightening look at three of the towering figures of science who unlocked many of the mysteries behind the laws of physics: Galileo, the first to take a close look at the process of free and restricted fall; Newton, originator of the concept of gravity as a universal force; and Einstein, who proposed that gravity is no more than the curvature of the four-dimensional space-time continuum.Graced with the author's own draw

  8. Lunar gravity affects leaf movement of Arabidopsis thaliana in the International Space Station.

    Science.gov (United States)

    Fisahn, Joachim; Klingelé, Emile; Barlow, Peter

    2015-06-01

    Cyclic leaf ascent and descent occur in synchrony and phase congruence with the lunisolar tidal force under a broad range of conditions. Digitized records of the vertical leaf movements of Arabidopsis thaliana were collected under space flight conditions in the International Space Station (ISS). Oscillations of leaf movements with periods of 45 and 90 min were found under light-adapted conditions, whereas in darkness, the periods were 45, 90, and 135 min. To demonstrate the close relationship between these oscillations and cyclical variations of the lunisolar gravitational force, we estimated the oscillations of the in-orbit lunisolar tide as they apply to the ISS, with the aid of the Etide software application. In general, in-orbit lunisolar gravitational profiles exhibited a periodicity of 45 min. Alignment of these in-orbit oscillations with the oscillations of Arabidopsis leaf movement revealed high degrees of synchrony and a congruence of phase. These data corroborate previous results which suggested a correlative relationship and a possible causal link between leaf movement rhythms obtained on ground and the rhythmic variation of the lunisolar tidal force.

  9. Super-resolution reconstruction and higher-degree function deformation model based matching for Chang’E-1 lunar images

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    This article intends to solve the matching problem of 2C level lunar images by Chang’E-1(CE-1)lunar probe satellite.A line-scanner image matching method is proposed which represents deformation by the quadric function along the camera motion direction and bases on the deformation model for a relief terrain’s imaging on sensors of the satellite borne three-line scanner camera.A precise matching is carried out for the normal view,the frontward view,and the backward view images of the CE-1 by combining the proposed method with the standard correlation method.A super-resolution(SR)reconstruction algorithm based on the wavelet interpolation of non-uniformly sampled data is also adopted to realize SR reconstruction of CE-1 lunar images,which adds the recognizable targets and explores CE-1 lunar images to the full.

  10. Super-resolution reconstruction and higher-degree function deformation model based matching for Chang'E-1 lunar images

    Institute of Scientific and Technical Information of China (English)

    LI LiChun; YU QiFeng; YUAN Yun; SHANG Yang; LU HongWei; SUN XiangYi

    2009-01-01

    This article intends to solve the matching problem of 2C level lunar images by Chang'E-1(CE-1)lunar probe satellite.A line-scanner image matching method is proposed which represents deformation by the quadric function along the camera motion direction and bases on the deformation model for a relief terrain's imaging on sensors of the satellite borne three-line scanner camera.A precise matching is carried out for the normal view,the frontward view,and the backward view images of the CE-1 by combining the proposed method with the standard correlation method.A super-resolution(SR)reconatruction algorithm based on the wavelet interpolation of non-uniformly sampled data is also adopted to realize SR reconstruction of CE-1 lunar images,which adds the recognizable targets and explores CE-1 lunar images to the full.

  11. Beyond the growth rate of cosmic structure: Testing modified gravity models with an extra degree of freedom

    Science.gov (United States)

    Burrage, Clare; Parkinson, David; Seery, David

    2017-08-01

    In "modified" gravity the observed acceleration of the universe is explained by changing the gravitational force law or the number of degrees of freedom in the gravitational sector. Both possibilities can be tested by measurements of cosmological structure formation. In this paper we elaborate the details of such tests using the Galileon model as a case study. We pay attention to the possibility that each new degree of freedom may have stochastically independent initial conditions, generating different types of potential well in the early universe and breaking complete correlation between density and velocity power spectra. This "stochastic bias" can confuse schemes to parametrize the predictions of modified gravity models, such as the use of the growth parameter f alone. Using data from the WiggleZ Dark Energy Survey we show that it will be possible to obtain constraints using information about the cosmological-scale force law embedded in the multipole power spectra of redshift-space distortions. As an example, we obtain an upper limit on the strength of the conformal coupling to matter in the cubic Galileon model, giving |1 /M |≲200 /MP . This allows the fifth-force to be stronger than gravity, but is consistent with zero coupling.

  12. 月球重力场模型精度比较研究%A Comparative Study on the Accuracy of Lunar Gravity Field Models

    Institute of Scientific and Technical Information of China (English)

    曹建峰; 胡松杰; 刘磊; 李勰; 黄勇; 张宇

    2012-01-01

    从阶方差、谱域分析以及大地水准面自由空气重力异常3个方面分析了月球重力场模型LP150Q,LP165P与SGM150各自的特点及差异,研究结果表明,SGM150重力场在中高阶项上得到了明显改善,在远月面可以发现明显的重力异常正负交替的现象.另外,对“嫦娥二号”变轨试验期间的测轨数据进行了轨道解算和预报,比较不同重力场模型的精度影响,发现基于SGM150模型的解算结果优于基于LP150Q和LP165P的,在定轨弧段内有10m量级的精度提升,可用于高精度的月球探测器精密定轨.%The features of and differences between the gravity models of LP150Q, LP165P and SGM150 are analyzed. Cross-power spectra of gravity and topography show there is more consistency between SGM150 and CLTM-sOl (Chang'E-l Lunar Topography Model-sOl) and the lunar gravity anomaly of SGM150 can better reveal the characteristics of the moon, especially its far-side. Orbit determination for Chang'E-2 at lOOkmX 100km and 100km X 15 km orbit phases is performed with different gravity field models. The results show a better orbit solution with lOm-level improvement can be obtained using SGM150 and the solution is more suitable for high accuracy orbit determination for lunar probes.

  13. Investigation of the Lunar Deep Interior by SELENE-2

    Science.gov (United States)

    Sasaki, Sho; Kikuchi, F.; Matsumoto, K.; Noda, H.; Araki, H.; Hanada, H.; Yamada, R.; Kunimori, H.; Iwata, T.; Kawaguchi, N.; Kono, Y.

    2012-10-01

    Measurements of gravity and rotation of planets and satellites are important tools to investigate their internal structure. Lunar surface tidal deformation is small (10cm). But effect of lunar tidal deformation can be detected by gravity change, through degree 2 potential Love number, k2, which could constrain the state of the core (solid or liquid) and viscosity of the lower mantle of the Moon. Dissipations of lunar librations also depend on core and lower mantle states. Liquid metallic core would be caused by significant amount of sulfur to lower core melting temperature, whereas low-viscosity lower mantle would suggest the presence of water. In effect, the pressure level of lunar lower mantle is compatible with that of terrestrial asthenosphere, where water in silicate decreases viscosity significantly. Existence of volatiles in lunar deeper interior would modify lunar evolution scenario of hot origin: from the giant impact through the magma ocean. The k2 is sensitive to the state of deep interior. When the core radius is 350 km, k2 value changes by about 5% between liquid and solid cores. SELENE-2 is a planned lunar lander-orbiter mission by JAXA after successful mission KAGUYA (SELENE). We propose VLBI radio (VRAD) sources both in SELENE-2 lander and orbiter. Using same-beam (or two-beam) multi-frequency VLBI, we will determine orbits of the orbiter precisely, measure low-order gravity changes, and estimate k2 with uncertainty below 1%. If the core size is constrained by SELENE-2 seismometer, contributions of lower mantle and core on k2 would separated. We also propose a Lunar Laser Ranging (LLR) reflector on SELENE-2 lander. With pre-existed reflectors, latitudinal component of lunar libration and its dissipation will be measured. Among LLR parameters, k2 and core oblateness are coupled. Once k2 is fixed, we can determine core oblateness, which would also constrain core and lower mantle states.

  14. Toxicity of lunar dust

    CERN Document Server

    Linnarsson, Dag; Fubini, Bice; Gerde, Per; Karlsson, Lars L; Loftus, David J; Prisk, G Kim; Staufer, Urs; Tranfield, Erin M; van Westrenen, Wim

    2012-01-01

    The formation, composition and physical properties of lunar dust are incompletely characterised with regard to human health. While the physical and chemical determinants of dust toxicity for materials such as asbestos, quartz, volcanic ashes and urban particulate matter have been the focus of substantial research efforts, lunar dust properties, and therefore lunar dust toxicity may differ substantially. In this contribution, past and ongoing work on dust toxicity is reviewed, and major knowledge gaps that prevent an accurate assessment of lunar dust toxicity are identified. Finally, a range of studies using ground-based, low-gravity, and in situ measurements is recommended to address the identified knowledge gaps. Because none of the curated lunar samples exist in a pristine state that preserves the surface reactive chemical aspects thought to be present on the lunar surface, studies using this material carry with them considerable uncertainty in terms of fidelity. As a consequence, in situ data on lunar dust...

  15. Comparison of upright LBPP and supine LBNP in terms of cardiovascular and biomechanical parameters to simulate 1/6-G (lunar gravity) and 3/8-G (Martian gravity) activities

    Science.gov (United States)

    Schlabs, Thomas; Rosales-Velderrain, Armando; Ruckstuhl, Heidi; Richardson, Sara E.; Hargens, Alan

    Background: Missions of astronauts to Moon and Mars may be planned in the future. From over 40 years of manned spaceflight it is known that the human body experiences cardiovascular and musculoskeletal losses and a decrease in aerobic fitness while exposed to reduced gravity. Because future missions will be much longer than before, further research is needed to improve Earth-based simulations of reduced gravity. Among others, two methods are capable of simu-lating fractional gravity on Earth: upright Lower Body Positive Pressure (LBPP) and supine Lower Body Negative Pressure (LBNP). No previous study has directly compared these two methods to determine which method is better suited to simulate both the biomechanical and cardiovascular responses of performing activity in lunar (1/6-G) and Martian (3/8-G) gravities. Taken previous studies into account and considering the fact that supine posture is closer to the established 10 head-up-tilt lunar simulation, we hypothesized that exercise performed in supine LBNP better simulates the cardiovascular conditions that occur in lunar and Martian gravities. Methods: 12 healthy normal subjects underwent a protocol consisting of resting and walking (0.25 Froude) with LBNP and LBPP. Each protocol was performed in simulated 1/6-G and 3/8-G. Heart-rate (HR), blood pressure, oxygen consumption (VO2), vertical component of the ground reaction force, comfort of the subject and perceived exertion of the subject (Borg Scale) were assessed. The obtained parameters were compared to predicted values for lunar and Martian gravity conditions in order to determine the method that shows the best level of agreement. Results: There was no difference in gait parameters between LBPP and LBNP simulation of lunar and Martian gravity (cadence: P=0.427, normalized stride length: P=0.373, duty fac-tor: P=0.302, and normalized vertical peak force (P=0.064). Mean blood pressure (P=0.398), comfort (P=0.832) and BORG rating (P=0.186) did not differ

  16. The Effect of Pre-Impact Porosity and Vertical Density Gradients on the Gravity Signature of Lunar Craters as Seen by GRAIL

    Science.gov (United States)

    Milbury, C.; Johnson, B. C.; Melosh, H., IV; Collins, G. S.; Blair, D. M.; Soderblom, J. M.; Nimmo, F.; Bierson, C. J.; Phillips, R. J.; Zuber, M. T.

    2015-12-01

    As a result of NASA's dual spacecraft Gravity Recovery And Interior Laboratory (GRAIL) mission [Zuber et al., 2013; doi:10.1126/science.1231507], we now know that the lunar crust is highly porous and that the porosity varies laterally [Wieczorek et al., 2013; doi:10.1126/science.1231530] and vertically [Besserer et al., 2014; doi:10.1002/2014GL060240]. Analysis of complex craters located within the lunar highlands reveals that: 1) craters larger than diameter D~210 have positive Bouguer Anomalies (BAs), 2) craters with D ≲ 100 km have both positive and negative BAs that vary about the (near 0) mean by approximately ± 25 mGal, and, 3) D and BA are anticorrelated for craters with D ≲ 100 km [Soderblom et al., 2015; submitted]. Numerical modeling by Milbury et al. [2015, LPSC] shows that pre-impact porosity is the dominant influence on the gravity signature of complex craters with D ≲ 100 km, and mantle uplift dominates the gravity for those with D > 140 km. Phillips et al. [2015, LPSC] showed that complex craters located in the South Pole-Aitken (SPA) basin tend to have more-negative BAs than similar craters in the highlands. By including (pre-impact) vertical porosity/density gradients in our impact simulations, we reproduce the observed anticorrelation between BA and D for D ≲ 100 km, and the observed difference between the BAs of SPA and highland craters. We use the iSALE hydrocode including pore space compaction [Wünnemann et al., 2006; doi:10.1016/j.icarus.2005.10.013] and dilatant bulking [Collins, 2014; doi:10.1002/2014JE004708] to understand how the gravity signature of impact craters develop. In this study we vary density/porosity with depth. We find that simulations that have constant porosity with depth have a lower BA for a given crater diameter than those with varying porosity. We used two different mean porosities (7% and 14%) and found that the BA increases with increasing porosity, similar to simulations with constant porosity. Larger

  17. Lunar Balance and Locomotion

    Science.gov (United States)

    Paloski, William H.

    2008-01-01

    Balance control and locomotor patterns were altered in Apollo crewmembers on the lunar surface, owing, presumably, to a combination of sensory-motor adaptation during transit and lunar surface operations, decreased environmental affordances associated with the reduced gravity, and restricted joint mobility as well as altered center-of-gravity caused by the EVA pressure suits. Dr. Paloski will discuss these factors, as well as the potential human and mission impacts of falls and malcoordination during planned lunar sortie and outpost missions. Learning objectives: What are the potential impacts of postural instabilities on the lunar surface? CME question: What factors affect balance control and gait stability on the moon? Answer: Sensory-motor adaptation to the lunar environment, reduced mechanical and visual affordances, and altered biomechanics caused by the EVA suit.

  18. Topographic gravity modeling for global Bouguer maps to degree 2160: Validation of spectral and spatial domain forward modeling techniques at the 10 microGal level

    Science.gov (United States)

    Hirt, Christian; Reußner, Elisabeth; Rexer, Moritz; Kuhn, Michael

    2016-09-01

    Over the past years, spectral techniques have become a standard to model Earth's global gravity field to 10 km scales, with the EGM2008 geopotential model being a prominent example. For some geophysical applications of EGM2008, particularly Bouguer gravity computation with spectral techniques, a topographic potential model of adequate resolution is required. However, current topographic potential models have not yet been successfully validated to degree 2160, and notable discrepancies between spectral modeling and Newtonian (numerical) integration well beyond the 10 mGal level have been reported. Here we accurately compute and validate gravity implied by a degree 2160 model of Earth's topographic masses. Our experiments are based on two key strategies, both of which require advanced computational resources. First, we construct a spectrally complete model of the gravity field which is generated by the degree 2160 Earth topography model. This involves expansion of the topographic potential to the 15th integer power of the topography and modeling of short-scale gravity signals to ultrahigh degree of 21,600, translating into unprecedented fine scales of 1 km. Second, we apply Newtonian integration in the space domain with high spatial resolution to reduce discretization errors. Our numerical study demonstrates excellent agreement (8 μGgal RMS) between gravity from both forward modeling techniques and provides insight into the convergence process associated with spectral modeling of gravity signals at very short scales (few km). As key conclusion, our work successfully validates the spectral domain forward modeling technique for degree 2160 topography and increases the confidence in new high-resolution global Bouguer gravity maps.

  19. Development of the negative gravity anomaly of the 85 degrees E Ridge, northeastern Indian Ocean – A process oriented modelling approach

    Digital Repository Service at National Institute of Oceanography (India)

    Sreejith, K.M.; Radhakrishna, M.; Krishna, K.S.; Majumdar, T.J.

    The 85 degrees E Ridge is associated with two contrasting gravity anomalies: negative anomaly over the north part (up to 5 degrees N latitude), where the ridge structure is buried under thick Bengal Fan sediments and positive anomaly over the south...

  20. Dissolution kinetics of a lunar glass simulant at 25 degrees C: the effect of pH and organic acids

    Science.gov (United States)

    Eick, M. J.; Grossl, P. R.; Golden, D. C.; Sparks, D. L.; Ming, D. W.

    1996-01-01

    The dissolution kinetics of a simulated lunar glass were examined at pH 3, 5, and 7. Additionally, the pH 7 experiments were conducted in the presence of citric and oxalic acid at concentrations of 2 and 20 mM. The organic acids were buffered at pH 7 to examine the effect of each molecule in their dissociated form. At pH 3, 5, and 7, the dissolution of the synthetic lunar glass was observed to proceed via a two-stage process. The first stage involved the parabolic release of Ca, Mg, Al, and Fe, and the linear release of Si. Dissolution was incongruent, creating a leached layer rich in Si and Ti which was verified by transmission electron microscopy (TEM). During the second stage the release of Ca, Mg, Al, and Fe was linear. A coupled diffusion/surface dissolution model was proposed for dissolution of the simulated lunar glass at pH 3, 5, and 7. During the first stage the initial release of mobile cations (i.e., Ca, Mg, Al, Fe) was limited by diffusion through the surface leached layer of the glass (parabolic release), while Si release was controlled by the hydrolysis of the Si-O-Al bonds at the glass surface (linear release). As dissolution continued, the mobile cations diffused from greater depths within the glass surface. A steady-state was then reached where the diffusion rate across the increased path lengths equalled the Si release rate from the surface. In the presence of the organic acids, the dissolution of the synthetic lunar glass proceeded by a one stage process. The release of Ca, Mg, Al, and Fe followed a parabolic relationship, while the release of Si was linear. The relative reactivity of the organic acids used in the experiments was citrate > oxalate. A thinner leached layer rich in Si/Ti, as compared to the pH experiments, was observed using TEM. Rate data suggest that the chemisorption of the organic anion to the surface silanol groups was responsible for enhanced dissolution in the presence of the organic acids. It is proposed that the increased

  1. Gravity anomalies over the central Indian ridge between 3 degree S and 11 degree S, Indian Ocean: Segmentation and crustal structure

    Digital Repository Service at National Institute of Oceanography (India)

    Samudrala, K.; KameshRaju, K.A; RamaRao, P.

    High-resolution shipboard geophysical investigations along the Indian Ocean ridge system are sparse especially over the Carlsberg and Central Indian ridges. In the present study, the shipboard gravity and multibeam bathymetry data acquired over a...

  2. Application of higher-order KdV-mKdV model with higher-degree nonlinear terms to gravity waves in atmosphere

    Institute of Scientific and Technical Information of China (English)

    Li Zi-Liang

    2009-01-01

    Higher-order Korteweg-de Vries (KdV)-modified KdV (mKdV) equations with a higher-degree of nonlinear terms are derived from a simple incompressible non-hydrostatic Boussinesq equation set in atmosphere and are used to investigate gravity waves in atmosphere. By taking advantage of the auxiliary nonlinear ordinary differential equation, periodic wave and solitary wave solutions of the fifth-order KdV-mKdV models with higher-degree nonlinear terms are obtained under some constraint conditions. The analysis shows that the propagation and the periodic structures of gravity waves depend on the properties of the slope of line of constant phase and atmospheric stability. The Jacobi elliptic function wave and solitary wave solutions with slowly varying amplitude are transformed into triangular waves with the abruptly varying amplitude and breaking gravity waves under the effect of atmospheric instability.

  3. Lunar cinder cones.

    Science.gov (United States)

    McGetchin, T R; Head, J W

    1973-04-01

    Data on terrestrial eruptions of pyroclastic material and ballistic considerations suggest that in the lunar environment (vacuum and reduced gravity) low-rimmed pyroclastic rings are formed rather than the high-rimmed cinder cones so abundant on the earth. Dark blanketing deposits in the Taurus-Littrow region (Apollo 17 landing area) are interpreted as being at least partly composed of lunar counterparts of terrestrial cinder cones.

  4. Lithospheric stretching and the long wavelength free-air gravity anomaly of the Eastern Continental margin of India and the 85 degree E Ridge, Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Rajesh, S.; Majumdar, T.J.; Krishna, K.S.

    Among the submarine ridge systems in the northern Indian Ocean, the 85 degree E Ridge in the Bay of Bengal is more enigmatic owing to its peculiar anomalous negative free-air gravity. In general, this has been attributed to the isostatic...

  5. Spinfoam Gravity

    Science.gov (United States)

    Bianchi, Eugenio

    The following sections are included: * Introduction * Topological Field Theory and Gravity * Classical Spinfoam Gravity: Degrees of Freedom and Foams * Unitary Representations of the Rotation and the Lorentz Group * Boundary Variables and the Loop Quantum Gravity Hilbert Space * Spinfoam Partition Function and the Vertex Amplitude * Cellular Quantum Geometry: A Single Atom of Space * Cellular Quantum Geometry: Coherent Spin-networks * Vertex-amplitude Asymptotics and Regge Gravity * Reconstructing a Semiclassical Spacetime * Conclusions * References

  6. NASA Lunar Robotics for Science and Exploration

    Science.gov (United States)

    Cohen, Barbara A.; Lavoie, Anthony R.; Gilbert, Paul A.; Horack, John M.

    2008-01-01

    This slide presentation reviews the robotic missions that NASA and the international partnership are undertaking to investigate the moon to support science and exploration objectives. These missions include the Lunar Reconnaissance Orbiter (LRO), Lunar Crater Observation and Sensing Satellite (LCROSS), Gravity Recovery and Interior Laboratory (GRAIL), Moon Mineralogy Mapper (MMM), Lunar Atmosphere, Dust and Environment Explorer (LADEE), and the International Lunar Network (ILN). The goals and instrumentation of these missions are reviewed.

  7. Copernicus: Lunar surface mapper

    Science.gov (United States)

    Redd, Frank J.; Anderson, Shaun D.

    1992-01-01

    The Utah State University (USU) 1991-92 Space Systems Design Team has designed a Lunar Surface Mapper (LSM) to parallel the development of the NASA Office of Exploration lunar initiatives. USU students named the LSM 'Copernicus' after the 16th century Polish astronomer, for whom the large lunar crater on the face of the moon was also named. The top level requirements for the Copernicus LSM are to produce a digital map of the lunar surface with an overall resolution of 12 meters (39.4 ft). It will also identify specified local surface features/areas to be mapped at higher resolutions by follow-on missions. The mapping operation will be conducted from a 300 km (186 mi) lunar-polar orbit. Although the entire surface should be mapped within six months, the spacecraft design lifetime will exceed one year with sufficient propellant planned for orbit maintenance in the anomalous lunar gravity field. The Copernicus LSM is a small satellite capable of reaching lunar orbit following launch on a Conestoga launch vehicle which is capable of placing 410 kg (900 lb) into translunar orbit. Upon orbital insertion, the spacecraft will weigh approximately 233 kg (513 lb). This rather severe mass constraint has insured attention to component/subsystem size and mass, and prevented 'requirements creep.' Transmission of data will be via line-of-sight to an earth-based receiving system.

  8. Lunar Analog

    Science.gov (United States)

    Cromwell, Ronita L.

    2009-01-01

    In this viewgraph presentation, a ground-based lunar analog is developed for the return of manned space flight to the Moon. The contents include: 1) Digital Astronaut; 2) Bed Design; 3) Lunar Analog Feasibility Study; 4) Preliminary Data; 5) Pre-pilot Study; 6) Selection of Stockings; 7) Lunar Analog Pilot Study; 8) Bed Design for Lunar Analog Pilot.

  9. Efficacy of Compression Garments to Simulate Fluid Shifts during Lunar Bedrest

    Science.gov (United States)

    Brinley, Alaina; Brown, Angela; Ribeiro, Christine; Summers, Richard; Platts, Steven H.

    2009-01-01

    The effectiveness of JOBST(Registered TradeMark) compression stockings for fluid redistribution was examined in the lunar bed rest analog based on Digital Astronaut computer model predictions. NASA's future goals include missions to the moon which will require extended exposure to the lunar gravity environment. To prepare for these missions, physiological adaptations in various systems must be resolved. A bed rest at a 10 degree head-up tilt was used to simulate lunar gravity. Plasma volume (PV) loss may cause some of the cardiovascular adaptations which occur during space flight so PV is measured in the bed rest analog to evaluate fluid loss. PV varies from individual to individual so PV index (PVI) is used to determine the magnitude and time course of fluid shift and cardiovascular adaptation to 1/6 g. The Digital Astronaut, a computer simulation tool, predicts a 6% PV loss during an extended simulated lunar mission for a male with a body surface area of 1.95 m(exp 2). Simple geometry calculations suggest that 10 degree head-up tilt is most useful for simulated measurement of deconditioning in bone and muscle, however, 2 degree head-up tilt may best imitate cardiovascular fluid shifts. In order to reconcile these different models, compression stocking must be used in the 10 degree paradigm to better approximate expected cardiovascular changes.

  10. Lunar preform manufacturing

    Science.gov (United States)

    Leong, Gregory N.; Nease, Sandra; Lager, Vicky; Yaghjian, Raffy; Waller, Chris

    A design for a machine to produce hollow, continuous fiber-reinforced composite rods of lunar glass and a liquid crystalline matrix using the pultrusion process is presented. The glass fiber will be produced from the lunar surface, with the machine and matrix being transported to the moon. The process is adaptable to the low gravity and near-vacuum environment of the moon through the use of a thermoplastic matrix in fiber form as it enters the pultrusion process. With a power consumption of 5 kW, the proposed machine will run unmanned continuously in fourteen-day cycles, matching the length of lunar days. A number of dies could be included that would allow the machine to produce rods of varying diameter, I-beams, angles, and other structural members. These members could then be used for construction on the lunar surface or transported for use in orbit. The benefits of this proposal are in the savings in weight of the cargo each lunar mission would carry. The supply of glass on the moon is effectively endless, so enough rods would have to be produced to justify its transportation, operation, and capital cost. This should not be difficult as weight on lunar mission is at a premium.

  11. Effects of torsional degree of freedom, geometric nonlinearity, and gravity on aeroelastic behavior of large-scale horizontal axis wind turbine blades under varying wind speed conditions

    DEFF Research Database (Denmark)

    Jeong, Min-Soo; Cha, Myung-Chan; Kim, Sang-Woo

    2014-01-01

    Modern horizontal axis wind turbine blades are long, slender, and flexible structures that can undergo considerable deformation, leading to blade failures (e.g., blade-tower collision). For this reason, it is important to estimate blade behaviors accurately when designing large-scale wind turbines....... In this study, a numerical analysis considering blade torsional degree of freedom, geometric nonlinearity, and gravity was utilized to examine the effects of these factors on the aeroelastic blade behavior of a large-scale horizontal axis wind turbine. The results predicted that flapwise deflection is mainly...... affected by the torsional degree of freedom, which causes the blade bending deflections to couple to torsional deformation, thereby varying the aerodynamic loads through changes in the effective angle of attack. Edgewise deflection and torsional deformation are mostly influenced by the periodic...

  12. GRAIL gravity field determination using the Celestial Mechanics Approach - status report

    Science.gov (United States)

    Arnold, Daniel; Bertone, Stefano; Jäggi, Adrian; Beutler, Gerhard; Mervart, Leos

    2015-04-01

    The NASA mission GRAIL (Gravity Recovery And Interior Laboratory) inherits its concept from the GRACE (Gravity Recovery And Climate Experiment) mission to determine the gravity field of the Moon. The use of inter-satellite Ka-band range-rate (KBRR) observations enables data aquisition even when the spacecraft are not tracked from the Earth. The data allows for a highly accurate estimation of the lunar gravity field on both sides of the Moon, which is crucial to improve the understanding of its internal structure and thermal evolution. In this presentation we discuss GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach using the Bernese Software. Currently, KBRR observations and position data (GNI1B products) are used to solve for the lunar gravity field parameters in a generalized orbit determination problem. Apart from normalized spherical harmonic coefficients up to degree n = 200, also arc-specific parameters like initial state vectors and appropriately spaced empirical parameters (pseudo-stochastic pulses and empirical accelerations) are set up as common parameters for all measurement types. The latter shall compensate for imperfect models of non-gravitational forces. In this respect, we present our advances towards a more realistic model of solar radiation pressure using empirical accelerations in appropriate directions. We compare our results from the nominal and from the extended mission phase with the most recent lunar gravity field models released by other groups, as well as their consistency with topography-induced gravity. We show that the lunar gravity field can be recovered with a high quality by adapting the Celestial Mechanics Approach, even when using pre-GRAIL or pre-SELENE gravity field models as a priori fields. As a further extension of our processing, the GNI1B positions are replaced by the original Doppler observations of the Deep Space Network (DSN) to allow for a completely independent determination of the lunar

  13. Year 3 LUNAR Annual Report to the NASA Lunar Science Institute

    CERN Document Server

    Burns, Jack

    2012-01-01

    The Lunar University Network for Astrophysics Research (LUNAR) is a team of researchers and students at leading universities, NASA centers, and federal research laboratories undertaking investigations aimed at using the Moon as a platform for space science. LUNAR research includes Lunar Interior Physics & Gravitation using Lunar Laser Ranging (LLR), Low Frequency Cosmology and Astrophysics (LFCA), Planetary Science and the Lunar Ionosphere, Radio Heliophysics, and Exploration Science. The LUNAR team is exploring technologies that are likely to have a dual purpose, serving both exploration and science. There is a certain degree of commonality in much of LUNAR's research. Specifically, the technology development for a lunar radio telescope involves elements from LFCA, Heliophysics, Exploration Science, and Planetary Science; similarly the drilling technology developed for LLR applies broadly to both Exploration and Lunar Science.

  14. Relative equilibria of full dynamics of a rigid body with gravitational orbit-attitude coupling in a uniformly rotating second degree and order gravity field

    Science.gov (United States)

    Wang, Yue; Xu, Shijie

    2014-12-01

    The motion of a rigid body in a uniformly rotating second degree and order gravity field is a good model for the gravitationally coupled orbit-attitude motion of a spacecraft in the close proximity of an asteroid. The relative equilibria of this full dynamics model are investigated using geometric mechanics from a global point of view. Two types of relative equilibria are found based on the equilibrium conditions: one is the Lagrangian relative equilibria, at which the circular orbit of the rigid body is in the equatorial plane of the central body; the other is the non-Lagrangian relative equilibria, at which the circular orbit is parallel to but not in the equatorial plane of central body. The existences of the Lagrangian and non-Lagrangian relative equilibria are discussed numerically with respect to the parameters of the gravity field and the rigid body. The effect of the gravitational orbit-attitude coupling is especially assessed. The existence region of the Lagrangian relative equilibria is given on the plane of the system parameters. Numerical results suggest that the negative C 20 with a small absolute value and a negative C 22 with a large absolute value favor the existence of the non-Lagrangian relative equilibria. The effect of the gravitational orbit-attitude coupling of the rigid body on the existence of the non-Lagrangian relative equilibria can be positive or negative, which depends on the harmonics C 20 and C 22, and the angular velocity of the rotation of the gravity field.

  15. Particle content and degrees of freedom of a gravitational field in 4th order theories of gravity

    Science.gov (United States)

    Moebius, K.

    In gravitational theories of fourth order, the influence of certain properties of the field equations (tracelessness, conformal invariance, scale invariance, or their breaking) for the particle content (number of degrees of freedom, mass, and spin) is investigated. Using the Cauchy initial-value problem and a counting method first developed by Einstein, it is possible to get a useful definition of the concept of the degrees of freedom for the full nonlinear theory. This is due to the fact that this method incorporates the concrete structure of the field equations (and thus their nonlinearities). Analyzing different general-relativistic field theories via these approaches, the influence of the various structures of nonlinearities is discussed. It is, in particular, shown that those results obtained by the spin projection formalism can be reproduced by nonlinear methods.

  16. Effect of centrifuge-induced artificial gravity and ergometric exercise on cardiovascular deconditioning, myatrophy, and osteoporosis induced by a -6 degrees head-down bedrest.

    Science.gov (United States)

    Iwase, Satoshi; Takada, Hiroki; Watanabe, Yoriko; Ishida, Koji; Akima, Hiroshi; Katayama, Keisho; Iwase, Mitsunori; Hirayanagi, Kaname; Shiozawa, Tomoki; Hamaoka, Takafumi; Masuo, Yoshihisa; Custaud, Marc-Antoine

    2004-07-01

    We have reported that centrifuge-induced artificial gravity with ergometric exercise could reduce developing cardiovascular deconditioning in humans. In the present study, we examined this load could prevent the myatrophy and osteoporosis induced by head-down bedrest for 20 days. Subjects were ten healthy male volunteers with informed consent. They were requested to lie down at -6 degrees for 20 days, and evaluation for cardiovascular deconditioning, myatrophy, and osteoporosis. As the result, high G-load with low intensity exercise suppressed the orthostatic intolerance and increase in serum osteoporotic marker, whereas low G-load with high intensity ergometric exercise maintained the maximal oxygen intake, heart dimension, and prevented myatrophy. The combination of high/low G-load with low/high intensity exercise will determine the optimal protocol for prevention of cardiovascular deconditioning, myatrophy, and osteoporosis.

  17. Lunar Navigator - A Miniature, Fully Autonomous, Lunar Navigation, Surveyor, and Range Finder System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Microcosm proposes to design and develop a fully autonomous Lunar Navigator based on our MicroMak miniature star sensor and a gravity gradiometer similar to one on a...

  18. Status of GRAIL Gravity Field Determination Using the Celestial Mechanics Approach

    Science.gov (United States)

    Arnold, Daniel; Beutler, Gerhard; Jäggi, Adrian; Bock, Heike; Mervart, Leos; Meyer, Ulrich; Bertone, Stefano

    To determine the gravity field of the Moon, the NASA mission GRAIL (Gravity Recovery And Interior Laboratory) inherits its concept from the Earth orbiting GRACE (Gravity Recovery and Climate Experiment) mission. The use of ultra-precise inter-satellite Ka-band ranging observations enables data acquisition even when the spacecraft are not tracked from the Earth. The data allows for a highly accurate estimation of the lunar gravity field with unprecedented resolution on both sides of the Moon, which is crucial to improve the understanding of its internal structure and thermal evolution. In this presentation we discuss GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach. Ka-band range-rate (KBRR) observations and position data (GNI1B products) are used to solve for the lunar gravity field parameters in a generalized orbit determination problem. Apart from normalized spherical harmonic coefficients up to degrees n≤ 200, also arc- and satellite-specific parameters, like initial state vectors and pseudo-stochastic pulses, are set up as common parameters for all measurement types. The latter shall compensate for imperfect models of non-gravitational accelerations, e.g., caused by solar radiation pressure. In addition, especially for the data of the primary mission phase, it is essential to estimate time bias parameters for the KBRR observations. We compare our results from the nominal mission phase with the official Level 2 gravity field models first released in October 2013. Our results demonstrate that the lunar gravity field can be recovered with a high quality by adapting the Celestial Mechanics Approach, even when using pre-GRAIL or pre-SELENE gravity field models as a priori fields and when replacing sophisticated models of non-gravitational accelerations by appropriately spaced and constrained pseudo-stochastic pulses. Yet, the usage of preprocessed position data as pseudo observations is not fully satisfying and is potentially

  19. Lunar Exploration Orbiter (LEO)

    Science.gov (United States)

    Jaumann, R.; Spohn, T.; Hiesinger, H.; Jessberger, E. K.; Neukum, G.; Oberst, J.; Helbert, J.; Christensen, U.; Keller, H. U.; Mall, U.; Böhnhardt, H.; Hartogh, P.; Glassmeier, K.-H.; Auster, H.-U.; Moreira, A.; Werner, M.; Pätzold, M.; Palme, H.; Wimmer-Schweingruber, R.; Mandea, M.; Lesur, V.; Häusler, B.; Hördt, A.; Eichentopf, K.; Hauber, E.; Hoffmann, H.; Köhler, U.; Kührt, E.; Michaelis, H.; Pauer, M.; Sohl, F.; Denk, T.; van Gasselt, S.

    2007-08-01

    The Moon is an integral part of the Earth-Moon system, it is a witness to more than 4.5 b. y. of solar system history, and it is the only planetary body except Earth for which we have samples from known locations. The Moon is our closest companion and can easily be reached from Earth at any time, even with a relatively modest financial budget. Consequently, the Moon was the first logical step in the exploration of our solar system before we pursued more distant targets such as Mars and beyond. The vast amount of knowledge gained from the Apollo and other lunar missions of the late 1960's and early 1970's demonstrates how valuable the Moon is for the understanding of our planetary system. Even today, the Moon remains an extremely interesting target scientifically and technologically, as ever since, new data have helped to address some of our questions about the Earth-Moon system, many questions remained. Therefore, returning to the Moon is the critical stepping-stone to further exploring our immediate planetary neighborhood. In this concept study, we present scientific and technological arguments for a national German lunar mission, the Lunar Explorations Orbiter (LEO). Numerous space-faring nations have realized and identified the unique opportunities related to lunar exploration and have planned missions to the Moon within the next few years. Among these missions, LEO will be unique, because it will globally explore the Moon in unprecedented spatial and spectral resolution. LEO will significantly improve our understanding of the lunar surface composition, surface ages, mineralogy, physical properties, interior, thermal history, gravity field, regolith structure, and magnetic field. The Lunar Explorations Orbiter will carry an entire suite of innovative, complementary technologies, including high-resolution camera systems, several spectrometers that cover previously unexplored parts of the electromagnetic spectrum over a broad range of wavelengths, microwave and

  20. Lunar horticulture.

    Science.gov (United States)

    Walkinshaw, C. H.

    1971-01-01

    Discussion of the role that lunar horticulture may fulfill in helping establish the life support system of an earth-independent lunar colony. Such a system is expected to be a hybrid between systems which depend on lunar horticulture and those which depend upon the chemical reclamation of metabolic waste and its resynthesis into nutrients and water. The feasibility of this approach has been established at several laboratories. Plants grow well under reduced pressures and with oxygen concentrations of less than 1% of the total pressure. The carbon dioxide collected from the lunar base personnel should provide sufficient gas pressure (approx. 100 mm Hg) for growing the plants.

  1. Scaling of Two-Phase Systems Across Gravity Levels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — There is a defined need for long term earth based testing for the development and deployment of two-phase flow systems in reduced-gravity, including lunar gravity,...

  2. 从日地系统L2出发借力月球飞越近地小行星%Near-Earth Asteroid Flyby Trajectories from the Sun-Earth L2 via Lunar Gravity Assist

    Institute of Scientific and Technical Information of China (English)

    何胜茂; 彭超; 高扬

    2016-01-01

    There are several flight options for the Chang’E-2 spacecraft after its remaining at the Sun-Earth L2 point, for example, impacting the Moon or recapture into lunar orbit, returning to Earth orbit or atmospheric reentry, heading for halo orbits of the Earth-Moon L1 or L2 or the Sun-Earth L1 point, as well as flying by near-Earth asteroids in interplanetary space (Finally, Chang’E-2 successfully implemented a close flyby of Toutatis, a potentially hazardous near-Earth asteroid, on Dec.13, 2012). The analyses of these flight options require designing preliminary transfer trajectories with total velocity impulses no more than 100 m/s in four-body dynamics, in which the motion of the spacecraft is influenced by the gravities of the Sun, Earth, and Moon. In this study, we shall present low-energy Toutatis flyby trajectories from a Sun-Earth L2 quasi-periodic orbit, specifically, via a single lunar gravity assist that is intentionally utilized for exploring potential benefits, compared with the direct transfer manner that is adopted in the practical mission. Compared with the direct transfer trajectories to the asteroid, lunar gravity assist is demonstrated to be capable of saving propellant for the Toutatis flyby mission, and the equivalent velocity impulses are 58.46 m/s.%对于停留在日地系统L2的“嫦娥2号”探测器,其后续飞行方案有多个选项,例如主动撞月或重返月球轨道、返回地球轨道或再入大气、飞往地月系统L1/L2或日地系统L1、进入深空飞越近地小行星(最终,“嫦娥2号”于2012年12月13日成功地实现了对Toutatis小行星的近距离飞越)。探讨上述的飞行方案需要对飞行轨道进行初步设计,总的速度脉冲限制在100 m/s以内并且需要考虑探测器同时受到太阳、地球、月球的引力作用。本研究设计了探测器从日地系统L2出发借力月球实现Toutatis小行星飞越的飞行方案,与直接飞越方案相比

  3. Lunar Mare Dome Identification and Morphologic Properties Analysis Using Chang'E-2 Lunar Data

    Science.gov (United States)

    Zeng, Xingguo; Mu, Lingli; Li, Chunlai; Liu, Jianjun; Ren, Xin; Wang, Yuanyuan

    2016-04-01

    Identify the lunar mare dome and study the morphologic properties to know more knowledge about the structure will enhance the study of lunar volcanism. Traditionally, most lunar domes are identified by the scientists from exploring the images or topographic maps of the lunar surface with manual method, which already found out a bunch of lunar domes in specific local areas. For the purpose of getting more knowledge about global lunar dome, it is necessary to identify the lunar dome from the global lunar mare. However, it is hard to find new lunar domes from the global lunar mare only with manual method, since in that case, the large volume lunar data is needed and such work is too time consumed, so that, there are few researchers who have indentified and study the properties of the lunar dome from the perspective of lunar global scale. To solve the problem mentioned above, in this approach , CE-2 DEM, DOM data in 7m resolution were used in the detection and morphologic analysis of the lunar domes and a dome detection method based on topographic characteristics were developed.We firstly designed a method considering the morphologic characteristics to identify the lunar dome with Chang'E2(CE-2) lunar global data, after that, the initial identified result with properties is analyzed, and finally, by integrating the result with lunar domes already found by former researchers, we made some maps about the spatial distribution of the global lunar mare dome. With the CE-2 data covering the former lunar domes and the new found lunar domes, we surveyed and calculated some morphologic properties, and found that, lunar domes are circular or eclipse shaped, obviously different from background in topography,which has a average diameter between 3-25km, circular degree less than 1.54, with a average slope less than 10°, average height less than 650m and diameter/height less than 0.065. Almost all of the lunar domes are located in the extent of 58°N~54°S,167°W~180°E,and nearly

  4. Lunar cement

    Science.gov (United States)

    Agosto, William N.

    1992-01-01

    With the exception of water, the major oxide constituents of terrestrial cements are present at all nine lunar sites from which samples have been returned. However, with the exception of relatively rare cristobalite, the lunar oxides are not present as individual phases but are combined in silicates and in mixed oxides. Lime (CaO) is most abundant on the Moon in the plagioclase (CaAl2Si2O8) of highland anorthosites. It may be possible to enrich the lime content of anorthite to levels like those of Portland cement by pyrolyzing it with lunar-derived phosphate. The phosphate consumed in such a reaction can be regenerated by reacting the phosphorus product with lunar augite pyroxenes at elevated temperatures. Other possible sources of lunar phosphate and other oxides are discussed.

  5. 基于激光干涉星间测距原理的下一代月球卫星重力测量计划需求论证%Demonstration of Requirement for Future Lunar Satellite Gravity Exploration Mission Based on Interferometric Laser Intersatellite Ranging Principle

    Institute of Scientific and Technical Information of China (English)

    郑伟; 许厚泽; 钟敏; 员美娟

    2011-01-01

    月球卫星重力测量是21世纪国际开展深空探测的发展趋势和追逐热点.月球重力场的精密测量是国际探月计划的重要组成部分,它决定着月球探测器的轨道优化设计和载人登月飞船月面理想着陆点的合适选取.本文首先介绍未来国际GRAIL(Gravity Recovery and Interior Laboratory)月球重力场探测双星计划的总体概述、关键载荷以及科学目标和研究方向.其次,重点阐述月球卫星观测模式可行性论证、月球卫星关键载荷的优化选取、卫星轨道参数的优化设计、仿真模拟研究的先期开展等我国将来月球卫星重力测量计划的实施建议.第一,由于高低/低低卫星跟踪卫星结合多普勒和甚长基线干涉系统观测模式(SST-HL/LL-Doppler-VLBI)对中长波月球重力场的探测精度较高,技术要求相对较低,月球重力场测定速度快、代价低和效益高,可借鉴地球重力卫星GRACE(Gravity Recovery and Climate Experiment)系统的成功经验,对定轨精度的要求较低,而且可有效探测远月面区域的月球重力场信号,因此我国将来首期月球卫星重力测量计划采用SST-HI/LL-Doppler-VLBI观测模式较优.第二,我国应先期开展高精度的月球重力卫星关键载荷(激光干涉星间测距仪、非保守力补偿系统等)和地面Doppler-VLBI系统的研制工作.第三,月球卫星轨道高度(50~100 km)和星间距离(100±50 km)的优化设计是成功实施将来我国月球卫星重力测量计划的重要保证.第四,建议我国将仿真技术应用于月球重力卫星的方案论证、系统设计、部件研制、产品检验、实际应用、故障分析等研制和运行的全过程.本文的研究不仅对我国将来首期月球卫星重力测量计划的成功实施具有重要的参考价值,同时对未来国际太阳系行星重力探测的发展方向具有广泛的指导意义.%The lunar satellite gravity exploration is the international

  6. The estimate on lunar figure

    Science.gov (United States)

    Gao, B. X.

    2008-10-01

    In 1799 Laplace had discovered that the lunar three principal momentum are not in equilibrium with the Moon's current orbital and rotational state.Some authors suggested that the Moon may carry a fossil figure. Before more 3 billion years the liquid Moon was closer to the Earth and revolved faster.Then the Moon migrated outwards and revolved slow down. During the early part of this migration, the Moon was continually subjected to tidal and rotational stretching and formed into an ellipsoid. Then the Moon cooled and solidified quickly. Eventually, the solid Moon's lithosphere was stable, so that we may see the very early lunar figure. In this paper, by using the lunar libration parameters and the spherical-harmonic gravity coefficient, the length of three radii a, b, c of the ellipsoid and the Moon's figure as an equilibrium tidal have been calculated. Then three conclusions can be obtained; (1) In the beginning the Moon may be very close to the Earth, before about 3 billion years the moon may cooled and solidified, and the present Moon are in the fossil figure. (2) In the third section of this paper, we demonstrate that the tidal deformation of liquid Moon was 1.934 times then the equilibrium tide. So that if to calculating the true lunar figure by using the lunar spherical-harmonic gravity coefficients, the effects of Liquid Love number hf = 1.934must be considered. (3) According to the difference between a, b, and c, the lunar distance (1.7455×108m) and spin period 3.652day can be calculated. So that the lunar orbits period was 8.34day. Hence the Moon was locked closely into a resonance orbit in the ratio 2:1 when the Moon froze.

  7. Lunar magnetism

    Science.gov (United States)

    Hood, L. L.; Sonett, C. P.; Srnka, L. J.

    1984-01-01

    Aspects of lunar paleomagnetic and electromagnetic sounding results which appear inconsistent with the hypothesis that an ancient core dynamo was the dominant source of the observed crustal magnetism are discussed. Evidence is summarized involving a correlation between observed magnetic anomalies and ejecta blankets from impact events which indicates the possible importance of local mechanisms involving meteoroid impact processes in generating strong magnetic fields at the lunar surface. A reply is given to the latter argument which also presents recent evidence of a lunar iron core.

  8. Noble Gases in the Lunar Regolith

    Institute of Scientific and Technical Information of China (English)

    邹永廖; 徐琳; 欧阳自远

    2003-01-01

    The most fundamental character of lunar soil is its high concentrations of solar-windimplanted dements,and the concentrations and behavior of the noble gases He,Ne,Ar,and Xe,which provide unique and extensive information about a broad range of fundamental problems. In this paper,the authors studied the forming mechanism of lunar regolith,and proposed that most of the noble gases in lunar regolith come from the solar wind. Meteoroid bombardment controls the maturity of lunar soil,with the degree of maturation decreasing with grain size; the concentrations of the noble gases would be of slight variation with the depth of lunar soil but tend to decrease with grain size. In addition,the concentrations of noble gases in lunar soil also show a close relationship with its mineral and chemical compositions. The utilization prospects of the noble gas s He in lunar regolith will be further discussed.

  9. 嫦娥三号姿轨控过程中GRAIL重力场模型的应用%Application of GRAIL Lunar Gravity Field Model in Attitude and Orbit Control for CE-3 Satellite

    Institute of Scientific and Technical Information of China (English)

    段建锋; 张宇; 陈明; 曹建峰; 王健

    2014-01-01

    嫦娥三号(CE-3)利用发动机力偶模式下喷气进行姿态控制,这对轨道的影响具有累积效应.GRAIL (Gravity Recovery And Interior Laboratory,重力恢复与内部实验室)月球重力场模型是美国国家航空航天局进行GRAIL探月计划的科学成果.为与LP(Lunar Prospector,月球勘探者)等月球重力场模型的定轨精度进行比较,利用重叠弧段法,分别选取CE-3环月段100 km×100 km圆轨道及100 km×15 km椭圆轨道各约1d的重叠弧段,使用LP重力场模型及GRAIL重力场模型进行定轨分析,比较重叠弧段精度.结果表明:使用GRAIL重力场模型可以明显降低定轨测距残差RMS(Root Mean Square,均方根)值,同时可以使重叠弧段精度提高1个量级.

  10. The Role of GRAIL Orbit Determination in Preprocessing of Gravity Science Measurements

    Science.gov (United States)

    Kruizinga, Gerhard; Asmar, Sami; Fahnestock, Eugene; Harvey, Nate; Kahan, Daniel; Konopliv, Alex; Oudrhiri, Kamal; Paik, Meegyeong; Park, Ryan; Strekalov, Dmitry; Watkins, Michael; Yuan, Dah-Ning

    2013-01-01

    The Gravity Recovery And Interior Laboratory (GRAIL) mission has constructed a lunar gravity field with unprecedented uniform accuracy on the farside and nearside of the Moon. GRAIL lunar gravity field determination begins with preprocessing of the gravity science measurements by applying corrections for time tag error, general relativity, measurement noise and biases. Gravity field determination requires the generation of spacecraft ephemerides of an accuracy not attainable with the pre-GRAIL lunar gravity fields. Therefore, a bootstrapping strategy was developed, iterating between science data preprocessing and lunar gravity field estimation in order to construct sufficiently accurate orbit ephemerides.This paper describes the GRAIL measurements, their dependence on the spacecraft ephemerides and the role of orbit determination in the bootstrapping strategy. Simulation results will be presented that validate the bootstrapping strategy followed by bootstrapping results for flight data, which have led to the latest GRAIL lunar gravity fields.

  11. Stability safety degree against sliding in high gravity dams%高重力坝抗滑稳定安全度分析

    Institute of Scientific and Technical Information of China (English)

    苏怀智; 刘红萍

    2011-01-01

    为了确保高重力坝的稳定安全,针对高重力坝坝基存在抗剪强度与正应力呈非线性关系的特点,重点研究了二次抛物线形的抗剪强度包络线.在此基础上,建立了基于二次抛物线形抗剪强度包络线的功能函数.结合改进的JC法,提出了高坝坝基失稳可靠度的计算方法,并开发了相应的程序.将上述基本原理和方法应用于某高坝工程除险加固后的稳定安全度校核,分析结果表明该坝经过除险加固处理后坝体具备一定的稳定安全储备能力.%In order to ensure the stability and safety of high gravity dams, the shear strength envelope curve in the shape of quadratic parabola was studied with regard to the nonlinear relationship between the shear strength and the normal stress for high dam foundations. On such a basis, a performance function based on the shear strength envelope curve in the shape of quadratic parabola was established. Combined with the improved JC method, a method for calculating the reliability of dam foundation failure was proposed, and the corresponding program was developed. The above basic principles and methods were applied to the calibration of safety degree for the stability of a high dam after rehabilitation. The results indicate that the dam has certain reserved capacity of stability safety after rehabilitation.

  12. Lunar origin from impact on the Earth

    Science.gov (United States)

    Stevenson, D. J.

    1984-01-01

    All theories of lunar origin involve events or processes which seemingly have low efficiencies or low probabilities or both. An impact-triggered fission lunar origin is presented. If the impact ejecta (a mixture of target and projectile) leave the impact site ballistically and are subsequently acted upon only by the gravity field of a spherical Earth, then the ejecta either reimpacts the Earth or escapes on a hyperbolic trajectory. Hence the need for a second burn. Three possible resolutions are considered: pressure gradient acceleration, non-central gravity, and viscous spreading.

  13. High Speed Lunar Navigation for Crewed and Remotely Piloted Vehicles

    Science.gov (United States)

    Pedersen, L.; Allan, M.; To, V.; Utz, H.; Wojcikiewicz, W.; Chautems, C.

    2010-01-01

    Increased navigation speed is desirable for lunar rovers, whether autonomous, crewed or remotely operated, but is hampered by the low gravity, high contrast lighting and rough terrain. We describe lidar based navigation system deployed on NASA's K10 autonomous rover and to increase the terrain hazard situational awareness of the Lunar Electric Rover crew.

  14. $BF$ gravity

    CERN Document Server

    Celada, Mariano; Montesinos, Merced

    2016-01-01

    $BF$ gravity comprises all the formulations of gravity that are based on deformations of $BF$ theory. Such deformations consist of either constraints or potential terms added to the topological $BF$ action that turn some of the gauge degrees of freedom into physical ones, particularly giving rise to general relativity. The $BF$ formulations have provided new and deep insights into many classical and quantum aspects of the gravitational field, setting the foundations for the approach to quantum gravity known as spinfoam models. In this review, we present a self-contained and unified treatment of the $BF$ formulations of $D$-dimensional general relativity and other related models, focusing on the classical aspects of them and including some new results.

  15. BF gravity

    Science.gov (United States)

    Celada, Mariano; González, Diego; Montesinos, Merced

    2016-11-01

    BF gravity comprises all the formulations of gravity that are based on deformations of BF theory. Such deformations consist of either constraints or potential terms added to the topological BF action that turn some of the gauge degrees of freedom into physical ones, particularly giving rise to general relativity. The BF formulations have provided new and deep insights into many classical and quantum aspects of the gravitational field, setting the foundations for the approach to quantum gravity known as spinfoam models. In this review, we present a self-contained and unified treatment of the BF formulations of D-dimensional general relativity and other related models, focusing on the classical aspects of them and including some new results.

  16. Lunar laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Keaton, P.W.; Duke, M.B.

    1986-01-01

    An international research laboratory can be established on the Moon in the early years of the 21st Century. It can be built using the transportation system now envisioned by NASA, which includes a space station for Earth orbital logistics and orbital transfer vehicles for Earth-Moon transportation. A scientific laboratory on the Moon would permit extended surface and subsurface geological exploration; long-duration experiments defining the lunar environment and its modification by surface activity; new classes of observations in astronomy; space plasma and fundamental physics experiments; and lunar resource development. The discovery of a lunar source for propellants may reduce the cost of constructing large permanent facilities in space and enhance other space programs such as Mars exploration. 29 refs.

  17. The Lunar Mapping and Modeling Project Update

    Science.gov (United States)

    Noble, S.; French, R.; Nall, M.; Muery, K.

    2010-01-01

    The Lunar Mapping and Modeling Project (LMMP) is managing the development of a suite of lunar mapping and modeling tools and data products that support lunar exploration activities, including the planning, design, development, test, and operations associated with crewed and/or robotic operations on the lunar surface. In addition, LMMP should prove to be a convenient and useful tool for scientific analysis and for education and public outreach (E/PO) activities. LMMP will utilize data predominately from the Lunar Reconnaissance Orbiter, but also historical and international lunar mission data (e.g. Lunar Prospector, Clementine, Apollo, Lunar Orbiter, Kaguya, and Chandrayaan-1) as available and appropriate. LMMP will provide such products as image mosaics, DEMs, hazard assessment maps, temperature maps, lighting maps and models, gravity models, and resource maps. We are working closely with the LRO team to prevent duplication of efforts and ensure the highest quality data products. A beta version of the LMMP software was released for limited distribution in December 2009, with the public release of version 1 expected in the Fall of 2010.

  18. Lunar Beagle and Lunar Astrobiology

    Science.gov (United States)

    Gibson, Everett K.; Pillinger, Colin T.; Waugh, Lester J.

    2010-12-01

    The study of the elements and molecules of astrobiological interest on the Moon can be made with the Gas Analysis Package (GAP) and associated instruments developed for the Beagle 2 Mars Express Payload. The permanently shadowed polar regions of the Moon may offer a unique location for the "cold-trapping" of the light elements (i.e. H, C, N, O, etc.) and their simple compounds. Studies of the returned lunar samples have shown that lunar materials have undergone irradiation with the solar wind and adsorb volatiles from possible cometary and micrometeoroid impacts. The Beagle 2's analytical instrument package including the sample processing facility and the GAP mass spectrometer can provide vital isotopic information that can distinguish whether the lunar volatiles are indigenous to the moon, solar wind derived, cometary in origin or from meteoroids impacting on the Moon. As future Lunar Landers are being considered, the suite of instruments developed for the Mars Beagle 2 lander can be consider as the baseline for any lunar volatile or resource instrument package.

  19. Clast Size, Void Space, and Degree of Contortion in Spatter Piles at Craters of the Moon, ID. Implications for Eruptions Conditions of Lunar Basalts.

    Science.gov (United States)

    Rader, E. L.; Heldmann, J. L.

    2016-12-01

    Spatter is an explosive volcanic product consisting of partially-molten clasts found predominantly in mafic eruptions. Classification of spatter deposits is currently based on qualitative visual identification, and its presence signifies little more than a near-vent environment. However, the variables that effect spatter morphology (density of clasts, aspect ratio of clasts, rind thickness, etc.) are related to heat transfer from the vent via convection and radiation to the atmosphere and conduction through the spatter pile. Subsequently, the heat flux is proportional to the volume and rate of eruption, as faster and more voluminous eruptions result in a higher degree of welding between clasts. With a quantitative classification scheme, spatter deposits may reveal important eruption conditions such as eruption duration, eruption vigor, and fountain height. These factors are particularly important for non-terrestrial volcanoes whose eruptions have never been observed and whose products will likely be sampled on too small of a scale for more detailed chemical and thermal analysis. This study describes physical aspects of multiple spatter deposits at Craters of the Moon National Monument in Idaho, and suggests different eruptions conditions will produce quantitatively unique spatter deposits.

  20. Lunar Orbit Stability for Small Satellite Mission Design

    Science.gov (United States)

    Dono, Andres

    2015-01-01

    The irregular nature of the lunar gravity field will severely affect the orbit lifetime and behavior of future lunar small satellite missions. These spacecraft need stable orbits that do not require large deltaV budgets for station-keeping maneuvers. The initial classical elements of any lunar orbit are critical to address its stability and to comply with mission requirements. This publication identifies stable regions according to different initial conditions at the time of lunar orbit insertion (LOI). High fidelity numerical simulations with two different gravity models were performed. We focus in low altitude orbits where the dominant force in orbit propagation is the existence of unevenly distributed lunar mass concentrations. These orbits follow a periodic oscillation in some of the classical elements that is particularly useful for mission design. A set of orbital maintenance strategies for various mission concepts is presented.

  1. Observational constraints on the identification of shallow lunar magmatism: Insights from floor-fractured craters

    Science.gov (United States)

    Jozwiak, L. M.; Head, J. W., III; Neumann, G. A.; Wilson, L.

    2017-02-01

    Floor-fractured craters are a class of lunar crater hypothesized to form in response to the emplacement of a shallow magmatic intrusion beneath the crater floor. The emplacement of a shallow magmatic body should result in a positive Bouguer anomaly relative to unaltered complex craters, a signal which is observed for the average Bouguer anomaly interior to the crater walls. We observe the Bouguer anomaly of floor-fractured craters on an individual basis using the unfiltered Bouguer gravity solution from GRAIL and also a degree 100-600 band-filtered Bouguer gravity solution. The low-magnitude of anomalies arising from shallow magmatic intrusions makes identification using unfiltered Bouguer gravity solutions inconclusive. The observed anomalies in the degree 100-600 Bouguer gravity solution are spatially heterogeneous, although there is spatial correlation between volcanic surface morphologies and positive Bouguer anomalies. We interpret these observations to mean that the spatial heterogeneity observed in the Bouguer signal is the result of variable degrees of magmatic degassing within the intrusions.

  2. Evaluating Material Flammability in Microgravity and Martian Gravity Compared to the NASA Standard Normal Gravity Test

    Science.gov (United States)

    Oslon, Sandra. L.; Ferkul, Paul

    2012-01-01

    Drop tower tests are conducted at Martian gravity to determine the flammability of three materials compared to previous tests in other normal gravity and reduced gravity environments. The comparison is made with consideration of a modified NASA standard test protocol. Material flammability limits in the different gravity and flow environments are tabulated to determine the factor of safety associated with normal gravity flammability screening. Previous testing at microgravity and Lunar gravity indicated that some materials burned to lower oxygen concentrations in low gravity than in normal gravity, although the low g extinction limit criteria are not the same as 1g due to time constraints in drop testing. Similarly, the data presented in this paper for Martian gravity suggest that there is a gravity level below Earth s at which materials burn more readily than on Earth. If proven for more materials, this may indicate the need to include a factor of safety on 1g flammability limits.

  3. [Effect of lunar dust on humans: -lunar dust: regolith-].

    Science.gov (United States)

    Morimoto, Yasuo; Miki, Takeo; Higashi, Toshiaki; Horie, Seichi; Tanaka, Kazunari; Mukai, Chiaki

    2010-09-01

    We reviewed the effect of lunar dust (regolith) on humans by the combination of the hazard/exposure of regolith and microgravity of the moon. With regard to the physicochemical properties of lunar dust, the hazard-related factors are its components, fibrous materials and nanoparticles. Animal exposure studies have been performed using a simulant of lunar dust, and it was speculated that the harmful effects of the simulant lies between those of crystalline silica and titanium dioxide. Fibrous materials may not have a low solubility judging from their components. The nanoparticles in lunar dust may have harmful potentials from the view of the components. As for exposure to regolith, there is a possibility that particles larger than ones in earth (1 gravity) are respirable. In microgravity, 1) the deposition of particles of less than 1 µm in diameter in the human lung did not decrease, 2) the functions of macrophages including phagocytosis were suppressed, 3) pulmonary inflammation was changed. These data on hazard/exposure and microgravity suggest that fine and ultrafine particles in regolith may have potential hazards and risks for humans.

  4. Lunar Dust Separation for Toxicology Studies

    Science.gov (United States)

    Cooper, Bonnie L.; McKay, D. S.; Riofrio, L. M.; Taylor, L. A.; Gonzalex, C. P.

    2010-01-01

    During the Apollo missions, crewmembers were briefly exposed to dust in the lunar module, brought in after extravehicular activity. When the lunar ascent module returned to micro-gravity, the dust that had settled on the floor now floated into the air, causing eye discomfort and occasional respiratory symptoms. Because our goal is to set an exposure standard for 6 months of episodic exposure to lunar dust for crew on the lunar surface, these brief exposures of a few days are not conclusive. Based on experience with industrial minerals such as sandblasting quartz, an exposure of several months may cause serious damage, while a short exposure may cause none. The detailed characteristics of sub-micrometer lunar dust are only poorly known, and this is the size range of particles that are of greatest concern. We have developed a method for extracting respirable dust (<2.5 micron) from Apollo lunar soils. This method meets stringent requirements that the soil must be kept dry, exposed only to pure nitrogen, and must conserve and recover the maximum amount of both respirable dust and coarser soil. In addition, we have developed a method for grinding coarser lunar soil to produce sufficient respirable soil for animal toxicity testing while preserving the freshly exposed grain surfaces in a pristine state.

  5. Understanding the Lunar System Architecture Design Space

    Science.gov (United States)

    Arney, Dale C.; Wilhite, Alan W.; Reeves, David M.

    2013-01-01

    Based on the flexible path strategy and the desire of the international community, the lunar surface remains a destination for future human exploration. This paper explores options within the lunar system architecture design space, identifying performance requirements placed on the propulsive system that performs Earth departure within that architecture based on existing and/or near-term capabilities. The lander crew module and ascent stage propellant mass fraction are primary drivers for feasibility in multiple lander configurations. As the aggregation location moves further out of the lunar gravity well, the lunar lander is required to perform larger burns, increasing the sensitivity to these two factors. Adding an orbit transfer stage to a two-stage lunar lander and using a large storable stage for braking with a one-stage lunar lander enable higher aggregation locations than Low Lunar Orbit. Finally, while using larger vehicles enables a larger feasible design space, there are still feasible scenarios that use three launches of smaller vehicles.

  6. Preliminary Results on Lunar Interior Properties from the GRAIL Mission

    Science.gov (United States)

    Williams, James G.; Konopliv, Alexander S.; Asmar, Sami W.; Lemoine, H. Jay; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Smith, David E.; Solomon, Sean C.; Watkins, Michael M.; Wieczorek, Mark A.; Zuber, Maria T.; Andrews-Hanna, Jeffrey C.; Head, James W.; Kiefer, Walter S.; Matsuyama, Isamu; McGovern, Patrick J.; Nimmo, Francis; Weber, Renee C.; Boggs, D. H.; Goossens, Sander J.; Kruizinga, Gerhard L.; Mazarico, Erwan; Park, Ryan S.; Yuan, Dah-Ning

    2013-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) mission has provided lunar gravity with unprecedented accuracy and resolution. GRAIL has produced a high-resolution map of the lunar gravity field while also determining tidal response. We present the latest gravity field solution and its preliminary implications for the Moon's interior structure, exploring properties such as the mean density, moment of inertia of the solid Moon, and tidal potential Love number k2. Lunar structure includes a thin crust, a deep mantle, a fluid core, and a suspected solid inner core. An accurate Love number mainly improves knowledge of the fluid core and deep mantle. In the future GRAIL will search for evidence of tidal dissipation and a solid inner core.

  7. Interaction between Escherichia coli and lunar fines

    Science.gov (United States)

    Johansson, K. R.

    1983-01-01

    A sample of mature lunar fines (10084.151) was solubilized to a high degree (about 17 percent) by the chelating agent salicylic acid (0.01. M). The neutralized (pH adjusted to 7.0) leachate was found to inhibit the growth of Escherichia coli (ATCC 259922) in a minimial mineral salts glucose medium; however, the inhibition was somewhat less than that caused by neutralized salicylic acid alone. The presence of lunar fines in the minimal medium was highly stimulatory to growth of E. coli following an early inhibitory response. The bacterium survived less well in the lunar leachate than in distilled water, no doubt because of the salicylate. It was concluded that the sample of lunar soil tested has nutritional value to E. coli and that certain products of fermentation helped to solubilize the lunar soil.

  8. Mechanical properties of lunar regolith and lunar soil simulant

    Science.gov (United States)

    Perkins, Steven W.

    1989-01-01

    Through the Surveyor 3 and 7, and Apollo 11-17 missions a knowledge of the mechanical properties of Lunar regolith were gained. These properties, including material cohesion, friction, in-situ density, grain-size distribution and shape, and porosity, were determined by indirect means of trenching, penetration, and vane shear testing. Several of these properties were shown to be significantly different from those of terrestrial soils, such as an interlocking cohesion and tensile strength formed in the absence of moisture and particle cementation. To characterize the strength and deformation properties of Lunar regolith experiments have been conducted on a lunar soil simulant at various initial densities, fabric arrangements, and composition. These experiments included conventional triaxial compression and extension, direct tension, and combined tension-shear. Experiments have been conducted at low levels of effective confining stress. External conditions such as membrane induced confining stresses, end platten friction and material self weight have been shown to have a dramatic effect on the strength properties at low levels of confining stress. The solution has been to treat these external conditions and the specimen as a full-fledged boundary value problem rather than the idealized elemental cube of mechanics. Centrifuge modeling allows for the study of Lunar soil-structure interaction problems. In recent years centrifuge modeling has become an important tool for modeling processes that are dominated by gravity and for verifying analysis procedures and studying deformation and failure modes. Centrifuge modeling is well established for terrestrial enginering and applies equally as well to Lunar engineering. A brief review of the experiments is presented in graphic and outline form.

  9. Integrated lunar materials manufacturing process

    Science.gov (United States)

    Gibson, Michael A. (Inventor); Knudsen, Christian W. (Inventor)

    1990-01-01

    A manufacturing plant and process for production of oxygen on the moon uses lunar minerals as feed and a minimum of earth-imported, process materials. Lunar feed stocks are hydrogen-reducible minerals, ilmenite and lunar agglutinates occurring in numerous, explored locations mixed with other minerals in the pulverized surface layer of lunar soil known as regolith. Ilmenite (FeTiO.sub.3) and agglutinates contain ferrous (Fe.sup.+2) iron reducible by hydrogen to yield H.sub.2 O and metallic Fe at about 700.degree.-1,200.degree. C. The H.sub.2 O is electrolyzed in gas phase to yield H.sub.2 for recycle and O.sub.2 for storage and use. Hydrogen losses to lunar vacuum are minimized, with no net hydrogen (or any other earth-derived reagent) consumption except for small leaks. Feed minerals are surface-mined by front shovels and transported in trucks to the processing area. The machines are manned or robotic. Ilmenite and agglutinates occur mixed with silicate minerals which are not hydrogen-reducible at 700.degree.-1,200.degree. C. and consequently are separated and concentrated before feeding to the oxygen generation process. Solids rejected from the separation step and reduced solids from the oxygen process are returned to the mine area. The plant is powered by nuclear or solar power generators. Vapor-phase water electrolysis, a staged, countercurrent, fluidized bed reduction reactor and a radio-frequency-driven ceramic gas heater are used to improve thermal efficiency.

  10. Lunar sulfur

    Science.gov (United States)

    Kuck, David L.

    Ideas introduced by Vaniman, Pettit and Heiken in their 1988 Uses of Lunar Sulfur are expanded. Particular attention is given to uses of SO2 as a mineral-dressing fluid. Also introduced is the concept of using sulfide-based concrete as an alternative to the sulfur-based concretes proposed by Leonard and Johnson. Sulfur is abundant in high-Ti mare basalts, which range from 0.16 to 0.27 pct. by weight. Terrestrial basalts with 0.15 pct. S are rare. For oxygen recovery, sulfur must be driven off with other volatiles from ilmenite concentrates, before reduction. Troilite (FeS) may be oxidized to magnetite (Fe3O4) and SO2 gas, by burning concentrates in oxygen within a magnetic field, to further oxidize ilmenite before regrinding the magnetic reconcentration. SO2 is liquid at -20 C, the mean temperature underground on the Moon, at a minimum of 0.6 atm pressure. By using liquid SO2 as a mineral dressing fluid, all the techniques of terrestrial mineral separation become available for lunar ores and concentrates. Combination of sulfur and iron in an exothermic reaction, to form iron sulfides, may be used to cement grains of other minerals into an anhydrous iron-sulfide concrete. A sulfur-iron-aggregate mixture may be heated to the ignition temperature of iron with sulfur to make a concrete shape. The best iron, sulfur, and aggregate ratios need to be experimentally established. The iron and sulfur will be by-products of oxygen production from lunar minerals.

  11. Reduced Gravity and Aerosol Deposition in the Human Lung

    Science.gov (United States)

    Darquenne, C.; Prisk, G. K.

    2017-06-01

    Studies during parabolic flights showed a significant effect of gravity on the amount and site of aerosol deposition in the lung, which may affect subsequent clearance and greatly increase the toxicological impact of inhaled lunar or martian dust.

  12. Hazard Detection Methods for Lunar Landing

    Science.gov (United States)

    Brady, Tye; Zimpfer, Doug; Robertson, Edward; Epp, Chirold; Paschall, Stephen

    2009-01-01

    The methods and experiences from the Apollo Program are fundamental building blocks for the development of lunar landing strategies for the Constellation Program. Each of the six lunar landing Apollo missions landed under near ideal lighting conditions. The astronauts visually performed terrain relative navigation while looking out of windows, and were greatly aided by external communication and well lit scenes. As the LM approached the landing site, the astronauts performed visual hazard detection and avoidance, also under near-ideal lighting conditions. The astronauts were looking out of the windows trying to the best of their ability to avoid rocks, slopes, and craters and find a safe landing location. NASA has expressed a desire for global lunar access for both crewed and robotic sortie lunar exploration missions (Cook, 2007) (Dale, 2006). Early NASA architecture studies have identified the lunar poles as desirable locations for early lunar missions. These polar missions have less than ideal lighting conditions and will significantly affect the way a crewed vehicle plans to land at such locales. Consequently, a variety of hazard identification methods should be considered for use by the crew to ensure a high degree of safety. This paper discusses such identification methods applicable to the poorly lit polar lunar environment, better ensuring global access for the soon to be designed Lunar Lander Vehicle (LLV).

  13. Gravity and non-locality

    CERN Document Server

    Diaz, Pablo; Walton, Mark

    2016-01-01

    With the aim of investigating the relation between gravity and non-locality at the classical level, we study a bilocal scalar field model. Bilocality introduces new (internal) degrees of freedom that can potentially reproduce gravity. We show that the equations of motion of the massless branch of the free bilocal model match those of linearized gravity. We also discuss higher orders of perturbation theory, where there is self-interaction in both gravity and the bilocal field sectors.

  14. Establishing a Formation of Small Satellites in a Lunar Flower Constellation

    Science.gov (United States)

    McManus, Lauren; Schaub, Hanspeter

    2016-12-01

    The success of previous lunar science missions can be expanded upon by using a constellation of satellites to increase the lunar surface coverage. A constellation could also serve as a communications or GPS network for a lunar human base. Small-sats, deployed from a single mothercraft, are proposed to achieve a lunar constellation. The establishment of a single- and multi-petal constellation is investigated where the mothercraft does the primary deployment maneuvers. The constellation lifetime and closed-loop maintenance are addressed once higher order lunar gravity fields and Earth/solar perturbations are included.

  15. Improving Realism in Reduced Gravity Simulators

    Science.gov (United States)

    Cowley, Matthew; Harvil, Lauren; Clowers, Kurt; Clark, Timothy; Rajulu, Sudhakar

    2010-01-01

    Since man was first determined to walk on the moon, simulating the lunar environment became a priority. Providing an accurate reduced gravity environment is crucial for astronaut training and hardware testing. This presentation will follow the development of reduced gravity simulators to a final comparison of environments between the currently used systems. During the Apollo program era, multiple systems were built and tested, with several NASA centers having their own unique device. These systems ranged from marionette-like suspension devices where the subject laid on his side, to pneumatically driven offloading harnesses, to parabolic flights. However, only token comparisons, if any, were made between systems. Parabolic flight allows the entire body to fall at the same rate, giving an excellent simulation of reduced gravity as far as the biomechanics and physical perceptions are concerned. While the effects are accurate, there is limited workspace, limited time, and high cost associated with these tests. With all mechanical offload systems only the parts of the body that are actively offloaded feel any reduced gravity effects. The rest of the body still feels the full effect of gravity. The Partial Gravity System (Pogo) is the current ground-based offload system used to training and testing at the NASA Johnson Space Center. The Pogo is a pneumatic type system that allows for offloaded motion in the z-axis and free movement in the x-axis, but has limited motion in the y-axis. The pneumatic system itself is limited by cylinder stroke length and response time. The Active Response Gravity Offload System (ARGOS) is a next generation groundbased offload system, currently in development, that is based on modern robotic manufacturing lines. This system is projected to provide more z-axis travel and full freedom in both the x and y-axes. Current characterization tests are underway to determine how the ground-based offloading systems perform, how they compare to parabolic

  16. Lunar remote sensing and measurements

    Science.gov (United States)

    Moore, H.J.; Boyce, J.M.; Schaber, G.G.; Scott, D.H.

    1980-01-01

    Remote sensing and measurements of the Moon from Apollo orbiting spacecraft and Earth form a basis for extrapolation of Apollo surface data to regions of the Moon where manned and unmanned spacecraft have not been and may be used to discover target regions for future lunar exploration which will produce the highest scientific yields. Orbital remote sensing and measurements discussed include (1) relative ages and inferred absolute ages, (2) gravity, (3) magnetism, (4) chemical composition, and (5) reflection of radar waves (bistatic). Earth-based remote sensing and measurements discussed include (1) reflection of sunlight, (2) reflection and scattering of radar waves, and (3) infrared eclipse temperatures. Photographs from the Apollo missions, Lunar Orbiters, and other sources provide a fundamental source of data on the geology and topography of the Moon and a basis for comparing, correlating, and testing the remote sensing and measurements. Relative ages obtained from crater statistics and then empirically correlated with absolute ages indicate that significant lunar volcanism continued to 2.5 b.y. (billion years) ago-some 600 m.y. (million years) after the youngest volcanic rocks sampled by Apollo-and that intensive bombardment of the Moon occurred in the interval of 3.84 to 3.9 b.y. ago. Estimated fluxes of crater-producing objects during the last 50 m.y. agree fairly well with fluxes measured by the Apollo passive seismic stations. Gravity measurements obtained by observing orbiting spacecraft reveal that mare basins have mass concentrations and that the volume of material ejected from the Orientale basin is near 2 to 5 million km 3 depending on whether there has or has not been isostatic compensation, little or none of which has occurred since 3.84 b.y. ago. Isostatic compensation may have occurred in some of the old large lunar basins, but more data are needed to prove it. Steady fields of remanent magnetism were detected by the Apollo 15 and 16 subsatellites

  17. Robotic Lunar Lander Development Project Status

    Science.gov (United States)

    Hammond, Monica; Bassler, Julie; Morse, Brian

    2010-01-01

    This slide presentation reviews the status of the development of a robotic lunar lander. The goal of the project is to perform engineering tests and risk reduction activities to support the development of a small lunar lander for lunar surface science. This includes: (1) risk reduction for the flight of the robotic lander, (i.e., testing and analyzing various phase of the project); (2) the incremental development for the design of the robotic lander, which is to demonstrate autonomous, controlled descent and landing on airless bodies, and design of thruster configuration for 1/6th of the gravity of earth; (3) cold gas test article in flight demonstration testing; (4) warm gas testing of the robotic lander design; (5) develop and test landing algorithms; (6) validate the algorithms through analysis and test; and (7) tests of the flight propulsion system.

  18. GRAVITY ANOMALIES OF THE MOON

    Directory of Open Access Journals (Sweden)

    S. G. Pugacheva

    2015-01-01

    Full Text Available The source of gravity anomalies of the Moon are large mascons with a high mass concentration at a depth of volcanic plains and lunar Maria. New data on the gravitational field of the Moon were obtained from two Grail spacecrafts. The article presents the data of physical and mechanical properties of the surface soil layer of the lunar Maria and gives an assessment of the chemical composition of the soil. There have been calculated heterogeneity parameters of the surface macro-relief of the lunar Maria: albedo, soil density, average grain diameter of the particles forming the surface layer and the volume fraction occupied by particles. It can be assumed that mascons include rich KREEP rocks with a high content of thorium and iron oxide. Formation of mascons is connected with intensive development of basaltic volcanism on the Moon in the early periods of its existence.

  19. Cis-Lunar Base Camp

    Science.gov (United States)

    Merrill, Raymond G.; Goodliff, Kandyce E.; Mazanek, Daniel D.; Reeves, John D., Jr.

    2012-01-01

    Historically, when mounting expeditions into uncharted territories, explorers have established strategically positioned base camps to pre-position required equipment and consumables. These base camps are secure, safe positions from which expeditions can depart when conditions are favorable, at which technology and operations can be tested and validated, and facilitate timely access to more robust facilities in the event of an emergency. For human exploration missions into deep space, cis-lunar space is well suited to serve as such a base camp. The outer regions of cis-lunar space, such as the Earth-Moon Lagrange points, lie near the edge of Earth s gravity well, allowing equipment and consumables to be aggregated with easy access to deep space and to the lunar surface, as well as more distant destinations, such as near-Earth Asteroids (NEAs) and Mars and its moons. Several approaches to utilizing a cis-lunar base camp for sustainable human exploration, as well as some possible future applications are identified. The primary objective of the analysis presented in this paper is to identify options, show the macro trends, and provide information that can be used as a basis for more detailed mission development. Compared within are the high-level performance and cost of 15 preliminary cis-lunar exploration campaigns that establish the capability to conduct crewed missions of up to one year in duration, and then aggregate mass in cis-lunar space to facilitate an expedition from Cis-Lunar Base Camp. Launch vehicles, chemical propulsion stages, and electric propulsion stages are discussed and parametric sizing values are used to create architectures of in-space transportation elements that extend the existing in-space supply chain to cis-lunar space. The transportation options to cis-lunar space assessed vary in efficiency by almost 50%; from 0.16 to 0.68 kg of cargo in cis-lunar space for every kilogram of mass in Low Earth Orbit (LEO). For the 15 cases, 5-year campaign

  20. An Estimate on the Lunar Figure

    Science.gov (United States)

    Gao, Bu-Xi

    In 1799 Laplace discovered that the three principal moments of the Moon are not in equilibrium with the Moon's current orbital and rotational state. Some authors suggested that the Moon may carry a fossil figure. More than 3 billion years ago, the liquid Moon was closer to the Earth and revolved faster. Then the Moon migrated outwards and its rotation slowed down. During the early stage of this migration, the Moon was continually subjected to tidal and rotational stretching and formed into an ellipsoid. Subsequently the Moon cooled down and solidified quickly. Eventually, the solid Moon's lithosphere was stable and as a result we may see the very early lunar figure. In this paper, by using the lunar libration parameters and the sphericalharmonic gravity coefficients, the lengths of three radii a, b and c of the ellipsoid and the Moon's figure in tidal equilibrium are calculated. We have obtained three main conclusions as follows. (1) In the very early stage the Moon may be very close to the Earth, then it cooled down and solidified about 3 billion years ago. The present Moon is a fossil figure. (2) We demonstrate in this paper that the tidal deformation of liquid Moon was 1.934 times larger than that of the equilibrium tide. So a liquid Love number of hf = 1 .934 must be taken into account when calculating the true lunar figure using the lunar spherical-harmonic gravity coefficients. (3) According to the differences between a, b and c, a Moon-Earth distance (1 .7455 × 10 8 m) and a lunar spin period (3.652 day) at the moment of its coagulation are determined. The lunar orbital period then is calculated (8.34 d). Finally we argue that the Moon was close to a 2:1 spin-orbit resonance when it froze.

  1. Genesis of the Lunar Landing Vehicle

    Science.gov (United States)

    Gelzer, Christian

    2009-01-01

    The author examines early research regarding return flight from a Moon landing made prior to President Kennedy's 1961 challenge to put men on the Moon before the end of the decade. Organizations involved in early research include NACA, the Flight Research Center (now Dryden) Bell Aircraft Corporation. The discussion focuses on development of a flight simulator to model the Moon's reduced gravity and development of the Lunar Landing Research Vehicle.

  2. Lunar Orbiter Photo Gallery

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Orbiter Photo Gallery is an extensive collection of over 2,600 high- and moderate-resolution photographs produced by all five of the Lunar Orbiter...

  3. Lunar Sample Compendium

    Data.gov (United States)

    National Aeronautics and Space Administration — The purpose of the Lunar Sample Compendium is to inform scientists, astronauts and the public about the various lunar samples that have been returned from the Moon....

  4. Lunar Sample Atlas

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Sample Atlas provides pictures of the Apollo samples taken in the Lunar Sample Laboratory, full-color views of the samples in microscopic thin-sections,...

  5. Lunar Surface Navigation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — To support extended lunar operations, precision localization and route mapping is required for planetary EVA, manned rovers and lunar surface mobility units. A...

  6. Lunar Sample Display Locations

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA provides a number of lunar samples for display at museums, planetariums, and scientific expositions around the world. Lunar displays are open to the public....

  7. Lunar electrical conductivity

    Science.gov (United States)

    Leavy, D.; Madden, T.

    1974-01-01

    It is pointed out that the lunar magnetometer experiment has made important contributions to studies of the lunar interior. Numerical inversions of the lunar electromagnetic response have been carried out, taking into account a void region behind the moon. The amplitude of the transfer function of an eight-layer model is considered along with a model of the temperature distribution inside the moon and the amplitude of the transfer function of a semiconductor lunar model.

  8. Lunar meteorites:witnesses of the composition and evolution of the Moon

    Institute of Scientific and Technical Information of China (English)

    MIAO Bingkui; CHEN Hongyi; XIA Zhipeng; YAO Jie; XIE Lanfang; NI Wenjun; ZHANG Chuantong

    2014-01-01

    Lunar meteorites are fragments of the Moon that escaped the gravity of the Moon following high-energy impacts by asteroids, subsequently fell to Earth. An inventory of 165 lunar meteorites has been developed since the discovery and identiifcation of the ifrst lunar meteorite, ALHA 81005, in 1979. Although the Apollo samples are much heavier in mass than lunar meteorites, the meteorites are still an important sample supplement for scientiifc research on the composition and history of the Moon. Apart from a small amount of unbrecciated crystalline rocks, the majority of lunar meteorites are breccias that can be classiifed into three groups:highland feldspathic breccia, mare basaltic breccia, and mingled(including lfedspathic and basaltic clasts) breccia. The petrography of lunar rocks suggests that there are a series of rock types of anorthosite, basalt, gabbro, troctolite, norite and KREEP in the Moon. Although KREEP is rare in lunar rocks, KREEP components have been found in the increasing number of lunar meteorites. KREEP provides important information on lunar magmatic evolution, e.g., the VHK KREEP clasts in SaU 169 may represent the pristine lunar magma (urKREEP). Six launching pairs of lunar meteorites have been proposed now, along with ten possible lunar launching sites. In addition, symplectite is often found in lunar basalts, which is a signiifcant record of shock metamorphism on the lunar surface. Furthermore, isotopic ages and noble gases not only provide information on crystallization processes in lunar rocks and the formation of lunar crust, but also provide insight into shock events on the lunar surface.

  9. Second Gravity

    CERN Document Server

    Nash, Patrick Lee

    2010-01-01

    A theory of a new gravitational interaction is described. This theory follows naturally from a new Lagrangian formulation of Maxwell's theory for photons and electrons (and positrons) whose associated Euler Lagrange equations imply the conventional Maxwell equations, but which possesses new \\textbf{\\emph{bosonic}} spinor degrees of freedom that may be associated with a new type of fundamental gravitational interaction. The precise character of this gravitational interaction with a photon vector potential is explicitly defined in terms of a local U(1)-invariant Lagrangian in Eq.[\\ref{Lagrangian3}]. However in Section \\ref{ssec:Simple-Cosmolo-Model}, in order to parallel the well known Friedmann model in cosmology, a phenomenological description of the new gravitational interaction coupled to Newton-Einstein gravity that is sourced by an ideal fluid is discussed. % % To lay the foundation for a description of the new gravitational interaction our new formulation of Maxwell's theory must first be described. It i...

  10. Ropeway material handling systems for lunar mining sites

    Science.gov (United States)

    Huttelmaier, H. P.; Carrick, Jonathan R.

    The feasibility of ropeways for short- as well as long-distance material hauling on the lunar surface is discussed. Existing experience in ropeways and relevant knowledge on lunar environmental contraints are summarized. It is suggested that ease of erection, adaptivity to varying transportation lengths and irregular terrain, as well as weight considerations will result in lunar ropeway applications. Ropeways are argued to be the most viable material-handling system for a lunar activity site on the basis of available technology. A low-capacity, reversible ropeway system which separates track and haul rope is the most feasible system. It is possible to apply sensing systems and automation to a high degree.

  11. Astronaut James Irwin keeps Lunar Roving Vehicle from sliding downhill

    Science.gov (United States)

    1971-01-01

    Astronaut James B. Irwin, lunar module pilot, holds the Lunar Roving Vehicle from sliding downhill during the second Apollo 15 lunar surface extravehicular activity. Apparently, both of the Rover's rear wheels are off the ground. The Rover was parked facing downhill on a 15 to 20 degree slope. Astronaut David R. Scott, commander, took this photograph. Scott was performing other tasks while Irwin held the Rover. They were parked at a 'fresh' crater on the Apennine Front (Hadley Delta Mountain) slope. In the foreground a lunar rake lies atop a mound.

  12. Lunar transportation scenarios utilising the Space Elevator.

    Science.gov (United States)

    Engel, Kilian A

    2005-01-01

    The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required delta v, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo.

  13. Massive Gravity

    National Research Council Canada - National Science Library

    de Rham, Claudia

    2014-01-01

    We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali–Gabadadze–Porrati model (DGP...

  14. Massive gravity

    OpenAIRE

    Claudia de Rham

    2016-01-01

    We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali-Gabadadze-Porrati model (DGP), cascading gravity, and ghost-free massive gravity. We then explore their theoretical and phenomenological consistency, proving the absence of Boulware-Deser ghosts and reviewing the Vainshtein mechanism and the cosmological solutions in these models. Finally, we present alt...

  15. Massive Gravity

    OpenAIRE

    de Rham, Claudia

    2014-01-01

    We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali-Gabadadze-Porrati model (DGP), cascading gravity, and ghost-free massive gravity. We then explore their theoretical and phenomenological consistency, proving the absence of Boulware-Deser ghosts and reviewing the Vainshtein mechanism and the cosmological solutions in these models. Finally, we present alt...

  16. Massive Gravity

    OpenAIRE

    2014-01-01

    We review recent progress in massive gravity. We start by showing how different theories of massive gravity emerge from a higher-dimensional theory of general relativity, leading to the Dvali–Gabadadze–Porrati model (DGP), cascading gravity, and ghost-free massive gravity. We then explore their theoretical and phenomenological consistency, proving the absence of Boulware–Deser ghosts and reviewing the Vainshtein mechanism and the cosmological solutions in these models. Finally, we present alt...

  17. Titan's gravity: An update

    Science.gov (United States)

    Durante, D.; Iess, L.; Racioppa, P.; Armstrong, J. W.; Lunine, J. I.; Stevenson, D. J.; Tortora, P.

    2016-12-01

    Since its arrival at Saturn in 2004, Cassini performed nine flybys devoted to the determination of Titan's gravity field and its tidal variations. The last gravity flyby of the mission (T122) took place on Aug. 10, 2016. We will present an updated gravity solution, based on all available data. These include also an additional flyby (T110, March 2015, primarily devoted to the imaging Titan's north polar lakes) carried out with the low gain antenna. This flyby was particularly valuable because closest approach occurred at high latitude (75°N), over an area not previously sampled. Published gravity results (Iess et al., 2012) indicated that Titan is subject to large eccentricity tides in response to Saturn's time varying forcing field. The magnitude of the response quadrupole field, controlled by the Love number k2, was used to infer the existence of an internal ocean. The new gravity field determination provides a better estimate of k2, to a level of a few percent. In addition to a full 3x3 field, the new solution includes also higher degree and order harmonic coefficients (such as J4) and offers an improved map of gravity anomalies. The updated geoid and its associated uncertainty could be used to refine the gravity-altimetry correlative analysis and for improved interpretation of radar altimetric data.

  18. Lunar Module 5 mated with Spacecraft Lunar Module Adapter (SLA)

    Science.gov (United States)

    1969-01-01

    Interior view of the Kennedy Space Center's (KSC) Manned Spacecraft Operations Building showing Lunar Module 5 mated to its Spacecraft Lunar Module Adapter (SLA). LM-5 is scheduled to be flown on the Apollo 11 lunar landing mission.

  19. Effect of the earth's ellipticity on the lunar tidal potential

    Science.gov (United States)

    Dahlen, F. A.

    1993-01-01

    The earth's orbital acceleration about the moon is influenced by its ellipticity. In this paper it shown that the ellipticity affects tidal gravity by contributing directly to the lunar tide-generating potential (in addition to effecting the elastic-gravitational response of the solid earth and oceans to this potential).

  20. Minimal massive 3D gravity

    NARCIS (Netherlands)

    Bergshoeff, Eric; Hohm, Olaf; Merbis, Wout; Routh, Alasdair J.; Townsend, Paul K.

    2014-01-01

    We present an alternative to topologically massive gravity (TMG) with the same 'minimal' bulk properties; i.e. a single local degree of freedom that is realized as a massive graviton in linearization about an anti-de Sitter (AdS) vacuum. However, in contrast to TMG, the new 'minimal massive gravity'

  1. Lunar Network Tracking Architecture for Lunar Flight

    OpenAIRE

    Robinson, Shane B.; Geller, David

    2010-01-01

    A trade study was conducted with the objective of comparing and contrasting the radiometric navigation performance provided by various architectures of lunar-based navigations assets. Architectures considered consist of a compliment of two beacons located on the lunar surface, and two orbiting beacons that provide range and range-rate measurements to the user. Configurations of these assets include both coplanar and linked constellations of frozen elliptic orbiters and halo orbiters. Each arc...

  2. Lunar surface magnetic fields and their interaction with the solar wind: results from lunar prospector

    Science.gov (United States)

    Lin; Mitchell; Curtis; Anderson; Carlson; McFadden; Acuna; Hood; Binder

    1998-09-04

    The magnetometer and electron reflectometer experiment on the Lunar Prospector spacecraft has obtained maps of lunar crustal magnetic fields and observed the interaction between the solar wind and regions of strong crustal magnetic fields at high selenographic latitude (30 degreesS to 80 degreesS) and low ( approximately 100 kilometers) altitude. Electron reflection maps of the regions antipodal to the Imbrium and Serenitatis impact basins, extending to 80 degreesS latitude, show that crustal magnetic fields fill most of the antipodal zones of those basins. This finding provides further evidence for the hypothesis that basin-forming impacts result in magnetization of the lunar crust at their antipodes. The crustal magnetic fields of the Imbrium antipode region are strong enough to deflect the solar wind and form a miniature (100 to several hundred kilometers across) magnetosphere, magnetosheath, and bow shock system.

  3. Lunar based massdriver applications

    Science.gov (United States)

    Ehresmann, Manfred; Gabrielli, Roland Atonius; Herdrich, Georg; Laufer, René

    2017-05-01

    The results of a lunar massdriver mission and system analysis are discussed and show a strong case for a permanent lunar settlement with a site near the lunar equator. A modular massdriver concept is introduced, which uses multiple acceleration modules to be able to launch large masses into a trajectory that is able to reach Earth. An orbital mechanics analysis concludes that the launch site will be in the Oceanus Procellarum a flat, Titanium rich lunar mare area. It is further shown that the bulk of massdriver components can be manufactured by collecting lunar minerals, which are broken down into its constituting elements. The mass to orbit transfer rates of massdriver case study are significant and can vary between 1.8 kt and 3.3 megatons per year depending on the available power. Thus a lunar massdriver would act as a catalyst for any space based activities and a game changer for the scale of feasible space projects.

  4. Lunar Exploration Manned and Unmanned

    Science.gov (United States)

    Spudis, P. D.; Asmar, S. W.; Bussey, D. B. J.; Duxbury, N.; Friesen, L. J.; Gillis, J. J.; Hawke, B. R.; Heiken, G.; Lawrence, D.; Manifold, J.; Slade, M. A.; Smith, A.; Taylor, G. J.; Yingst, R. A.

    2002-08-01

    The past decade has seen two global reconnaissance missions to the Moon, Clementine and Lunar Prospector, which have mapped the surface in multiple wavelengths, determined the Moon's topography and gravity fields, and discovered the presence of water ice in the permanently dark regions near the poles. Although we have learned much about the Moon, many key aspects of its history and evolution remain obscure. The three highest priority questions in lunar science are: 1) the Moon's global composition, particularly the abundance of aluminum and magnesium; 2) the extent, composition, and physical state of polar deposits, including the extent, purity, and thickness of ice, the elemental, isotopic, and molecular composition of polar volatiles, the environment of the polar regions; and 3) the cratering chronology of the Moon and the implications of a possibly unique history, such as a cataclysm, for our understanding of other Solar System objects. Answering and addressing these questions require a series of new missions, including an orbiter (carrying XRF, imaging radar, and other instruments), the deployment of surface network stations equipped with seismometers and heat flow probes, selected robotic sample return missions from geologically simple areas (e.g., youngest lava flow or crater melt sheet), and complex geological field work, conducted by human explorers. Because the Moon is a touchstone for the history and evolution of other rocky bodies in the solar system, we believe that these questions are of very high scientific priority and that lunar missions should receive much more serious attention and detailed study than they have in the past by the NASA Office of Space Science.

  5. Interior Alaska Bouguer Gravity Anomaly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Complete Bouguer Anomaly gravity grid of interior Alaska. All grid cells within the rectangular data area (from 61 to 66 degrees North latitude and...

  6. Lunar and interplanetary trajectories

    CERN Document Server

    Biesbroek, Robin

    2016-01-01

    This book provides readers with a clear description of the types of lunar and interplanetary trajectories, and how they influence satellite-system design. The description follows an engineering rather than a mathematical approach and includes many examples of lunar trajectories, based on real missions. It helps readers gain an understanding of the driving subsystems of interplanetary and lunar satellites. The tables and graphs showing features of trajectories make the book easy to understand. .

  7. LUNAR AND PLANETARY RESEARCH.

    Science.gov (United States)

    SPECTRA, LUNAR ENVIRONMENTS, MERCURY ( PLANET ), PLANETS , SURFACE PROPERTIES, SCIENTIFIC RESEARCH....MARS( PLANET ), *VENUS( PLANET ), *MOON, *ASTRONOMY, OPTICAL SCANNING, SPECTROSCOPY, OPTICAL ANALYSIS, INFRARED SPECTRA, ULTRAVIOLET SPECTRA, VISIBLE

  8. Properties of the Lunar Interior: Preliminary Results from the GRAIL Mission

    Science.gov (United States)

    Williams, James G.; Konopliv, Alexander S.; Asmar, Sami W.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Smith, David E.; Solomon, Sean C.; Watkins, Michael M.; Wieczorek, Mark A.; Zuber, Maria T.; Andrews-Hanna, Jeffrey C.; Head, James W.; Kiefer, Walter S.; McGovern, Patrick J.; Nimmo, Francis; Taylor, G. Jeffrey; Weber, Renee C.; Boggs, D. H.; Goossens, Sander J.; Kruizinga, Gerhard L.; Mazarico, Erwan; Park, Ryan S.; Yuan, Dah-Ning

    2013-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) mission [1] has provided lunar gravity with unprecedented accuracy and resolution. GRAIL has produced a high-resolution map of the lunar gravity field [2,3] while also determining tidal response. We present the latest gravity field solution and its preliminary implications for the Moon's interior structure, exploring properties such as the mean density, moment of inertia of the solid Moon, and tidal potential Love number k(sub 2). Lunar structure includes a thin crust, a thick mantle layer, a fluid outer core, and a suspected solid inner core. An accurate Love number mainly improves knowledge of the fluid core and deep mantle. In the future, we will search for evidence of tidal dissipation and a solid inner core using GRAIL data.

  9. Lunar Navigation Determination System - LaNDS

    Science.gov (United States)

    Quinn, David; Talabac, Stephen

    2012-01-01

    A portable comprehensive navigational system has been developed that both robotic and human explorers can use to determine their location, attitude, and heading anywhere on the lunar surface independent of external infrastructure (needs no Lunar satellite network, line of sight to the Sun or Earth, etc.). The system combines robust processing power with an extensive topographical database to create a real-time atlas (GIS Geospatial Information System) that is able to autonomously control and monitor both single unmanned rovers and fleets of rovers, as well as science payload stations. The system includes provisions for teleoperation and tele-presence. The system accepts (but does not require) inputs from a wide range of sensors. A means was needed to establish a location when the search is taken deep in a crater (looking for water ice) and out of view of Earth or any other references. A star camera can be employed to determine the user's attitude in menial space and stellar map in body space. A local nadir reference (e.g., an accelerometer that orients the nadir vector in body space) can be used in conjunction with a digital ephemeris and gravity model of the Moon to isolate the latitude, longitude, and azimuth of the user on the surface. That information can be used in conjunction with a Lunar GIS and advanced navigation planning algorithms to aid astronauts (or other assets) to navigate on the Lunar surface.

  10. Causality in 3D Massive Gravity Theories

    CERN Document Server

    Edelstein, Jose D; Kilicarslan, Ercan; Leoni, Matias; Tekin, Bayram

    2016-01-01

    We study the constraints coming from local causality requirement in various 2+1 dimensional dynamical theories of gravity. In Topologically Massive Gravity, with a single parity noninvariant massive degree of freedom, and in New Massive Gravity, with two massive spin-$2$ degrees of freedom, causality and unitarity are compatible with each other and they both require the Newton's constant to be negative. In their extensions, such as the Born-Infeld gravity and the minimal massive gravity the situation is similar and quite different from their higher dimensional counterparts, such as quadratic (e.g., Einstein-Gauss-Bonnet) or cubic theories, where causality and unitarity are in conflict.

  11. Integrated Suit Test 1 - A Study to Evaluate Effects of Suit Weight, Pressure, and Kinematics on Human Performance during Lunar Ambulation

    Science.gov (United States)

    Gernhardt, Michael L.; Norcross, Jason; Vos, Jessica R.

    2008-01-01

    In an effort to design the next generation Lunar suit, NASA has initiated a series of tests aimed at understanding the human physiological and biomechanical affects of space suits under a variety of conditions. The first of these tests was the EVA Walkback Test (ICES 2007-01-3133). NASA-JSC assembled a multi-disciplinary team to conduct the second test of the series, titled Integrated Suit Test 1 (IST-1), from March 6 through July 24, 2007. Similar to the Walkback Test, this study was performed with the Mark III (MKIII) EVA Technology Demonstrator suit, a treadmill, and the Partial Gravity Simulator in the Space Vehicle Mock-Up Facility at Johnson Space Center. The data collected for IST-1 included metabolic rates, ground reaction forces, biomechanics, and subjective workload and controllability feedback on both suited and unsuited (shirt-sleeve) astronaut subjects. For IST-1 the center of gravity was controlled to a nearly perfect position while the weight, pressure and biomechanics (waist locked vs. unlocked) were varied individually to evaluate the effects of each on the ability to perform level (0 degree incline) ambulation in simulated Lunar gravity. The detailed test methodology and preliminary key findings of IST-1 are summarized in this report.

  12. Low-Gravity Mimicking Simulants and Evaluation of Simulant Flow Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This project will provide a new method for testing flow/no-flow conditions and other gravity-driven flow behavior of Lunar or planetary regolith under reduced...

  13. Neil Armstrong At Lunar Landing Research Facility

    Science.gov (United States)

    1969-01-01

    Nearly 25 years ago, on July 20,1969, Neil Armstrong, shown here with NASA Langley Research Centers Lunar Excursion Module (LEM) Simulator, became the first human to walk on the moon after practicing with the simulator in May of 1969. Training with the simulator, part of Langleys Lunar Research Facility, allowed the Apollo astronauts to study and safely overcome problems that could have occurred during the final 150-foot descent to the surface of the moon. NASA needed such a facility in order to explore and develop techniques for landing the LEM on the moons surface, where gravity is only one-sixth as strong as on the Earth, as well as to determine the limits of human piloting capabilities in the new surroundings. This unique facility, completed in 1965 and now a National Historic Landmark, effectively canceled all but one-sixth of Earths gravitational force by using an overhead cable system.

  14. Structure and Evolution of the Lunar Interior

    Science.gov (United States)

    Andrews-Hanna, J. C.; Weber, R. C.; Ishihara, Y.; Kamata, S.; Keane, J.; Kiefer, W. S.; Matsuyama, I.; Siegler, M.; Warren, P.

    2017-01-01

    Early in its evolution, the Moon underwent a magma ocean phase leading to its differentiation into a feldspathic crust, cumulate mantle, and iron core. However, far from the simplest view of a uniform plagioclase flotation crust, the present-day crust of the Moon varies greatly in thickness, composition, and physical properties. Recent significant improvements in both data and analysis techniques have yielded fundamental advances in our understanding of the structure and evolution of the lunar interior. The structure of the crust is revealed by gravity, topography, magnetics, seismic, radar, electromagnetic, and VNIR remote sensing data. The mantle structure of the Moon is revealed primarily by seismic and laser ranging data. Together, this data paints a picture of a Moon that is heterogeneous in all directions and across all scales, whose structure is a result of its unique formation, differentiation, and subsequent evolution. This brief review highlights a small number of recent advances in our understanding of lunar structure.

  15. The lunar cart

    Science.gov (United States)

    Miller, G. C.

    1972-01-01

    Expanded experiment-carrying capability, to be used between the Apollo 11 capability and the lunar roving vehicle capability, was defined for the lunar surface crewmen. Methods used on earth to satisfy similar requirements were studied. A two-wheeled cart was built and tested to expected mission requirements and environments. The vehicle was used successfully on Apollo 14.

  16. A lunar venture

    Science.gov (United States)

    Lee, Joo Ahn; Trinh, Lu X.

    1989-01-01

    As the Earth's space station is in its final stages of design, the dream of a permanent manned space facility is now a reality. Despite this monumental achievement, however, man's quest to extend human habitation further out into space is far from being realized. The next logical step in space exploration must be the construction of a permanent lunar base. This lunar infrastucture can, in turn, be used as a staging ground for further exploration of the remote regions of the solar system. As outlined by the National Aeronautics and Space Administration, the lunar base program consists of three exploratory and implementation phases. In response to the technological and facility requirements of Phase 1 and 2 of this program, the Aerospace Vehicle Design Program of the University of Virgina (UVA) is proud to present a preliminary design for such a lunar infrastructure. This study is a comprehensive evaluation of the mission requirements as well as the design criteria for space vehicles and facilities. The UVA Lunar Venture is a dual system that consists of a lunar space station and a fleet of lunar landers/transporters. With such a design, it is demonstrated that all initial exploratory and construction requirements for the lunar base can be efficiently satisfied. Additionally, the need for such a dual system is justified both from a logistic and economic standpoint.

  17. Gravity investigations

    Energy Technology Data Exchange (ETDEWEB)

    Healey, D.L. [Geological Survey, Denver, CO (USA)

    1983-12-31

    A large density contrast exists between the Paleozoic rocks (including the rocks of Climax stock) and less dense, Tertiary volcanic rocks and alluvium. This density contrast ranges widely, and herein for interpretive purposes, is assumed to average 0.85 Mg/m{sup 3} (megagrams per cubic meter). The large density contrast makes the gravity method a useful tool with which to study the interface between these rock types. However, little or no density contrast is discernible between the sedimentary Paleozoic rocks that surround the Climax stock and the intrusive rocks of the stock itself. Therefore the gravity method can not be used to define the configuration of the stock. Gravity highs coincide with outcrops of the dense Paleozoic rocks, and gravity lows overlie less-dense Tertiary volcanic rocks and Quaternary alluvium. The positions of three major faults (Boundary, Yucca, and Butte faults) are defined by steep gravity gradients. West of the Climax stock, the Tippinip fault has juxtaposed Paleozoic rocks of similar density, and consequently, has no expression in the gravity data in that area. The gravity station spacing, across Oak Spring Butte, is not sufficient to adequately define any gravity expression of the Tippinip fault. 18 refs., 5 figs.

  18. Nonlocal gravity

    CERN Document Server

    Mashhoon, Bahram

    2017-01-01

    Relativity theory is based on a postulate of locality, which means that the past history of the observer is not directly taken into account. This book argues that the past history should be taken into account. In this way, nonlocality---in the sense of history dependence---is introduced into relativity theory. The deep connection between inertia and gravitation suggests that gravity could be nonlocal, and in nonlocal gravity the fading gravitational memory of past events must then be taken into account. Along this line of thought, a classical nonlocal generalization of Einstein's theory of gravitation has recently been developed. A significant consequence of this theory is that the nonlocal aspect of gravity appears to simulate dark matter. According to nonlocal gravity theory, what astronomers attribute to dark matter should instead be due to the nonlocality of gravitation. Nonlocality dominates on the scale of galaxies and beyond. Memory fades with time; therefore, the nonlocal aspect of gravity becomes wea...

  19. Finite Quantum Gravity

    CERN Document Server

    Modesto, Leonardo

    2013-01-01

    We hereby present a class of multidimensional higher derivative theories of gravity that realizes an ultraviolet completion of Einstein general relativity. This class is marked by a "non-polynomal" entire function (form factor), which averts extra degrees of freedom (including ghosts) and improves the high energy behavior of the loop amplitudes. By power counting arguments, it is proved that the theory is super-renormalizable in any dimension, i.e. only one-loop divergences survive. Furthermore, in odd dimensions there are no counter terms for pure gravity and the theory turns out to be "finite." Finally, considering the infinite tower of massive states coming from dimensional reduction, quantum gravity is finite in even dimension as well.

  20. Human Performance in Simulated Reduced Gravity Environments

    Science.gov (United States)

    Cowley, Matthew; Harvill, Lauren; Rajulu, Sudhakar

    2014-01-01

    NASA is currently designing a new space suit capable of working in deep space and on Mars. Designing a suit is very difficult and often requires trade-offs between performance, cost, mass, and system complexity. Our current understanding of human performance in reduced gravity in a planetary environment (the moon or Mars) is limited to lunar observations, studies from the Apollo program, and recent suit tests conducted at JSC using reduced gravity simulators. This study will look at our most recent reduced gravity simulations performed on the new Active Response Gravity Offload System (ARGOS) compared to the C-9 reduced gravity plane. Methods: Subjects ambulated in reduced gravity analogs to obtain a baseline for human performance. Subjects were tested in lunar gravity (1.6 m/sq s) and Earth gravity (9.8 m/sq s) in shirt-sleeves. Subjects ambulated over ground at prescribed speeds on the ARGOS, but ambulated at a self-selected speed on the C-9 due to time limitations. Subjects on the ARGOS were given over 3 minutes to acclimate to the different conditions before data was collected. Nine healthy subjects were tested in the ARGOS (6 males, 3 females, 79.5 +/- 15.7 kg), while six subjects were tested on the C-9 (6 males, 78.8 +/- 11.2 kg). Data was collected with an optical motion capture system (Vicon, Oxford, UK) and was analyzed using customized analysis scripts in BodyBuilder (Vicon, Oxford, UK) and MATLAB (MathWorks, Natick, MA, USA). Results: In all offloaded conditions, variation between subjects increased compared to 1-g. Kinematics in the ARGOS at lunar gravity resembled earth gravity ambulation more closely than the C-9 ambulation. Toe-off occurred 10% earlier in both reduced gravity environments compared to earth gravity, shortening the stance phase. Likewise, ankle, knee, and hip angles remained consistently flexed and had reduced peaks compared to earth gravity. Ground reaction forces in lunar gravity (normalized to Earth body weight) were 0.4 +/- 0.2 on

  1. A simulation of the Four-way lunar Lander-Orbiter tracking mode for the Chang'E-5 mission

    Science.gov (United States)

    Li, Fei; Ye, Mao; Yan, Jianguo; Hao, Weifeng; Barriot, Jean-Pierre

    2016-06-01

    The Chang'E-5 mission is the third phase of the Chinese Lunar Exploration Program and will collect and return lunar samples. After sampling, the Orbiter and the ascent vehicle will rendezvous and dock, and both spacecraft will require high precision orbit navigation. In this paper, we present a novel tracking mode-Four-way lunar Lander-Orbiter tracking that possibly can be employed during the Chang'E-5 mission. The mathematical formulas for the Four-way lunar Lander-Orbiter tracking mode are given and implemented in our newly-designed lunar spacecraft orbit determination and gravity field recovery software, the LUnar Gravity REcovery and Analysis Software/System (LUGREAS). The simulated observables permit analysis of the potential contribution Four-way lunar Lander-Orbiter tracking could make to precision orbit determination for the Orbiter. Our results show that the Four-way lunar Lander-Orbiter Range Rate has better geometric constraint on the orbit, and is more sensitive than the traditional two-way range rate that only tracks data between the Earth station and lunar Orbiter. After combining the Four-way lunar Lander-Orbiter Range Rate data with the traditional two-way range rate data and considering the Lander position error and lunar gravity field error, the accuracy of precision orbit determination for the Orbiter in the simulation was improved significantly, with the biggest improvement being one order of magnitude, and the Lander position could be constrained to sub-meter level. This new tracking mode could provide a reference for the Chang'E-5 mission and have enormous potential for the positioning of future lunar farside Lander due to its relay characteristic.

  2. High-precision gravimetric survey in support of lunar laser ranging at Haleakala, Maui, 1976 - 1978

    Science.gov (United States)

    Schenck, B. E.; Laurila, S. H.

    1978-01-01

    The planning, observations and adjustment of high-precision gravity survey networks established on the islands of Maui and Oahu as part of the geodetic-geophysical program in support of lunar laser ranging at Haleakala, Maui, Hawaii are described. The gravity survey networks include 43 independently measured gravity differences along the gravity calibration line from Kahului Airport to the summit of Mt. Haleakala, together with some key points close to tidal gauges on Maui, and 40 gravity differences within metropolitan Honolulu. The results of the 1976-1978 survey are compared with surveys made in 1961 and in 1964-1965. All final gravity values are given in the system of the international gravity standardization net 1971 (IGSN 71); values are obtained by subtracting 14.57 mgal from the Potsdam value at the gravity base station at the Hickam Air Force Base, Honolulu.

  3. Living matter: the "lunar eclipse" phenomena.

    Science.gov (United States)

    Korpan, Nikolai N

    2010-01-01

    The present investigations describe a unique phenomenon, namely the phenomenon of the "lunar eclipse", which has been observed and discovered by the author in living substance during the freeze-thawing processes in vivo using temperatures of various intensities and its cryosurgical response in animal experiment. Similar phenomena author has observed in nature, namely the total lunar eclipse and total solar eclipse. In this experimental study 76 animals (mongrel dogs) were investigated. A disc cryogenic probe was placed on the pancreas after the laparotomy. For cryosurgical exposure a temperature range of -40 degrees C, -80 degrees C, -120 degrees C and -180 degrees C was selected in contact with pancreas parenchyma. The freeze-thaw cycle was monitored by intraoperative ultrasound before, during and after cryosurgery. Each cryolesion was observed for one hour after thawing intraoperatively. Immediately after freezing, during the thawing process, the snow-white pancreas parenchyma, frozen hard to an ice block and resembling a full moon with a sharp demarcation line, gradually assumed a ruby-red shade and a hemispherical shape as it grew in size depend on reconstruction vascular circulation from the periphery to the center. This snow-white cryogenic lesion dissolved in the same manner in all animal tissues. The "lunar eclipse" phenomenon contributes to a fundamental understanding of the mechanisms of biological tissue damage during low temperature exposure in cryoscience and cryomedicine. Properties of the pancreas parenchyma response during the phenomenon of the "lunar eclipse" provide important insights into the mechanisms of damage and the formation of cryogenic lesion immediately after thawing in cryosurgery. Vascular changes and circulatory stagnation are commonly considered to be the main mechanism of biological tissue injury during low temperature exposure. The phenomenon of the "lunar eclipse" suggests that cryosurgery is the first surgical technique to use

  4. The Lunar Regolith

    Science.gov (United States)

    Noble, Sarah

    2009-01-01

    A thick layer of regolith, fragmental and unconsolidated rock material, covers the entire lunar surface. This layer is the result of the continuous impact of meteoroids large and small and the steady bombardment of charged particles from the sun and stars. The regolith is generally about 4-5 m thick in mare regions and 10-15 m in highland areas (McKay et al., 1991) and contains all sizes of material from large boulders to sub-micron dust particles. Below the regolith is a region of large blocks of material, large-scale ejecta and brecciated bedrock, often referred to as the "megaregolith". Lunar soil is a term often used interchangeably with regolith, however, soil is defined as the subcentimeter fraction of the regolith (in practice though, soil generally refers to the submillimeter fraction of the regolith). Lunar dust has been defined in many ways by different researchers, but generally refers to only the very finest fractions of the soil, less than approx.10 or 20 microns. Lunar soil can be a misleading term, as lunar "soil" bears little in common with terrestrial soils. Lunar soil contains no organic matter and is not formed through biologic or chemical means as terrestrial soils are, but strictly through mechanical comminution from meteoroids and interaction with the solar wind and other energetic particles. Lunar soils are also not exposed to the wind and water that shapes the Earth. As a consequence, in contrast to terrestrial soils, lunar soils are not sorted in any way, by size, shape, or chemistry. Finally, without wind and water to wear down the edges, lunar soil grains tend to be sharp with fresh fractured surfaces.

  5. Artificial Gravity

    CERN Document Server

    Clément, Gilles

    2007-01-01

    Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term reduced gravity during surface operations will require effective, multi-system countermeasures. Artificial gravity, which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by short-radius human centrifuge devices within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient

  6. The fractured Moon: Production and saturation of porosity in the lunar highlands from impact cratering

    Science.gov (United States)

    Soderblom, Jason M.; Evans, Alexander J.; Johnson, Brandon C.; Melosh, H. Jay; Miljković, Katarina; Phillips, Roger J.; Andrews-Hanna, Jeffrey C.; Bierson, Carver J.; Head, James W.; Milbury, Colleen; Neumann, Gregory A.; Nimmo, Francis; Smith, David E.; Solomon, Sean C.; Sori, Michael M.; Wieczorek, Mark A.; Zuber, Maria T.

    2015-09-01

    We have analyzed the Bouguer anomaly (BA) of ~1200 complex craters in the lunar highlands from Gravity Recovery and Interior Laboratory observations. The BA of these craters is generally negative, though positive BA values are observed, particularly for smaller craters. Crater BA values scale inversely with crater diameter, quantifying how larger impacts produce more extensive fracturing and dilatant bulking. The Bouguer anomaly of craters larger than 93-19+47 km in diameter is independent of crater size, indicating that there is a limiting depth to impact-generated porosity, presumably from pore collapse associated with either overburden pressure or viscous flow. Impact-generated porosity of the bulk lunar crust is likely in a state of equilibrium for craters smaller than ~30 km in diameter, consistent with an ~8 km thick lunar megaregolith, whereas the gravity signature of larger craters is still preserved and provides new insight into the cratering record of even the oldest lunar surfaces.

  7. Early Modified Gravity: Implications for Cosmology

    CERN Document Server

    Brax, Philippe; Clesse, Sebastien; Davis, Anne-Christine; Sculthorpe, Gregory

    2013-01-01

    We study the effects of modifications of gravity after Big Bang Nucleosynthesis (BBN) which would manifest themselves mainly before recombination. We consider their effects on the Cosmic Microwave Background (CMB) radiation and on the formation of large scale structure. The models that we introduce here represent all screened modifications of General Relativity (GR) which evade the local tests of gravity such as the violation of the strong equivalence principle as constrained by the Lunar Ranging experiment. We use the tomographic description of modified gravity which defines models with screening mechanisms of the chameleon or Damour-Polyakov types and allows one to relate the temporal evolution of the mass and the coupling to matter of a scalar field to its Lagrangian and also to cosmological perturbations. The models with early modifications of gravity all involve a coupling to matter which is stronger in the past leading to effects on perturbations before recombination while minimising deviations from Lam...

  8. Solar-system tests of the relativistic gravity

    CERN Document Server

    Ni, Wei-Tou

    2016-01-01

    In 1859, Le Verrier discovered the Mercury perihelion advance anomaly. This anomaly turned out to be the first relativistic-gravity effect observed. During the 156 years to 2016, the precisions and accuracies of laboratory and space experiments, and of astrophysical and cosmological observations on relativistic gravity have been improved by 3-4 orders of magnitude. The improvements have been mainly from optical observations at first followed by radio observations. The achievements for the past 50 years are from radio Doppler tracking and radio ranging together with lunar laser ranging. At the present, the radio observations and lunar laser ranging experiments are similar in the accuracy of testing relativistic gravity. We review and summarize the present status of solar-system tests of relativistic gravity. With planetary laser ranging, spacecraft laser ranging and interferometric laser ranging (laser Doppler ranging) together with the development of drag-free technology, the optical observations will improve...

  9. Gravity brake

    Science.gov (United States)

    Lujan, Richard E.

    2001-01-01

    A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.

  10. Building Strategic Capabilities for Sustained Lunar Exploration

    Science.gov (United States)

    Landgraf, M.; Hufenbach, B.; Houdou, B.

    2016-11-01

    We discuss a lunar exploration architecture that addresses the strategic objective of providing access to the lunar surface. This access enables the most exciting part of the lunar exploration: building a sustained infrastructure on the lunar surface.

  11. Lunar Health Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — During the Phase II Lunar Health Monitor program, Orbital Research will develop a second generation wearable sensor suite for astronaut physiologic monitoring. The...

  12. Lunar Map Catalog

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Map Catalog includes various maps of the moon's surface, including Apollo landing sites; earthside, farside, and polar charts; photography index maps; zone...

  13. Lunar Excavator Validation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Energid Technologies proposes to create a tool for simulation-based verification of lunar excavator designs. Energid will combine the best of 1) automatic control...

  14. Lunar Reconnaissance Orbiter

    Science.gov (United States)

    Morgan, T.; Chin, G.

    2007-08-01

    NASA's Lunar Reconnaissance Orbiter (LRO) plans to launch in October 2008 with a companion secondary impactor mission, LCROSS, as the inaugural missions for the Exploration System Mission Directorate. LRO is a pathfinder whose objective is to obtain the needed information to prepare for eventual human return to the Moon. LRO will undertake at least one baseline year of operation with additional extended mission phase sponsored by NASA's Science Mission Directorate. LRO will employ six individual instruments to produce accurate maps and high-resolution images of future landing sites, to assess potential lunar resources, and to characterize the radiation environment. LRO will also test the feasibility of one advanced technology demonstration package. The LRO payload includes: Lunar Orbiter Laser Altimeter (LOLA) which will determine the global topography of the lunar surface at high resolution, measure landing site slopes, surface roughness, and search for possible polar surface ice in shadowed regions; Lunar Reconnaissance Orbiter Camera (LROC) which will acquire targeted narrow angle images of the lunar surface capable of resolving meter-scale features to support landing site selection, as well as wide-angle images to characterize polar illumination conditions and to identify potential resources; Lunar Exploration Neutron Detector (LEND) which will map the flux of neutrons from the lunar surface to search for evidence of water ice, and will provide space radiation environment measurements that may be useful for future human exploration; Diviner Lunar Radiometer Experiment (DLRE) which will chart the temperature of the entire lunar surface at approximately 300 meter horizontal resolution to identify cold-traps and potential ice deposits; Lyman-Alpha Mapping Project (LAMP) which will map the entire lunar surface in the far ultraviolet. LAMP will search for surface ice and frost in the polar regions and provide images of permanently shadowed regions illuminated only

  15. Gravity waves

    Science.gov (United States)

    Fritts, David

    1987-02-01

    Gravity waves contributed to the establishment of the thermal structure, small scale (80 to 100 km) fluctuations in velocity (50 to 80 m/sec) and density (20 to 30%, 0 to peak). Dominant gravity wave spectrum in the middle atmosphere: x-scale, less than 100 km; z-scale, greater than 10 km; t-scale, less than 2 hr. Theorists are beginning to understand middle atmosphere motions. There are two classes: Planetary waves and equatorial motions, gravity waves and tidal motions. The former give rise to variability at large scales, which may alter apparent mean structure. Effects include density and velocity fluctuations, induced mean motions, and stratospheric warmings which lead to the breakup of the polar vortex and cooling of the mesosphere. On this scale are also equatorial quasi-biennial and semi-annual oscillations. Gravity wave and tidal motions produce large rms fluctuations in density and velocity. The magnitude of the density fluctuations compared to the mean density is of the order of the vertical wavelength, which grows with height. Relative density fluctuations are less than, or of the order of 30% below the mesopause. Such motions may cause significant and variable convection, and wind shear. There is a strong seasonal variation in gravity wave amplitude. Additional observations are needed to address and quantify mean and fluctuation statistics of both density and mean velocity, variability of the mean and fluctuations, and to identify dominant gravity wave scales and sources as well as causes of variability, both temporal and geographic.

  16. SO(3) massive gravity

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chunshan

    2013-11-25

    In this Letter, we propose a massive gravity theory with 5 degrees of freedom. The mass term is constructed by 3 Stückelberg scalar fields, which respects SO(3) symmetry in the fields' configuration. By the analysis on the linear cosmological perturbations, we found that such 5 d.o.f. are free from ghost instability, gradient instability, and tachyonic instability.

  17. Compact objects in Horndeski gravity

    CERN Document Server

    Silva, Hector O; Minamitsuji, Masato; Berti, Emanuele

    2016-01-01

    Horndeski gravity holds a special position as the most general extension of Einstein's theory of general relativity with a single scalar degree of freedom and second-order field equations. Because of these features, Horndeski gravity is an attractive phenomenological playground to investigate the consequences of modifications of general relativity in cosmology and astrophysics. We present a review of the progress made so far in the study of compact objects (black holes and neutron stars) within Horndeski gravity. In particular, we review our recent work on slowly rotating black holes and present some new results on slowly rotating neutron stars.

  18. Lunar biological effects and the magnetosphere.

    Science.gov (United States)

    Bevington, Michael

    2015-12-01

    The debate about how far the Moon causes biological effects has continued for two millennia. Pliny the Elder argued for lunar power "penetrating all things", including plants, fish, animals and humans. He also linked the Moon with tides, confirmed mathematically by Newton. A review of modern studies of biological effects, especially from plants and animals, confirms the pervasive nature of this lunar force. However calculations from physics and other arguments refute the supposed mechanisms of gravity and light. Recent space exploration allows a new approach with evidence of electromagnetic fields associated with the Earth's magnetotail at full moon during the night, and similar, but more limited, effects from the Moon's wake on the magnetosphere at new moon during the day. The disturbance of the magnetotail is perhaps shown by measurements of electric fields of up to 16V/m compared with the usual effects on some sensitive organisms. Similar intensities found in sferics, geomagnetic storms, aurora disturbance, sensations of a 'presence' and pre-seismic electromagnetic radiation are known to affect animals and 10-20% of the human population. There is now evidence for mechanisms such as calcium flux, melatonin disruption, magnetite and cryptochromes. Both environmental and receptor variations explain confounding factors and inconsistencies in the evidence. Electromagnetic effects might also account for some evolutionary changes. Further research on lunar biological effects, such as acute myocardial infarction, could help the development of strategies to reduce adverse effects for people sensitive to geomagnetic disturbance. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. The Lunar IceCube Mission Design: Construction of Feasible Transfer Trajectories with a Constrained Departure

    Science.gov (United States)

    Folta, David C.; Bosanac, Natasha; Cox, Andrew; Howell, Kathleen C.

    2016-01-01

    Lunar IceCube, a 6U CubeSat, will prospect for water and other volatiles from a low-periapsis, highly inclined elliptical lunar orbit. Injected from Exploration Mission-1, a lunar gravity assisted multi-body transfer trajectory will capture into a lunar science orbit. The constrained departure asymptote and value of trans-lunar energy limit transfer trajectory types that re-encounter the Moon with the necessary energy and flight duration. Purdue University and Goddard Space Flight Center's Adaptive Trajectory Design tool and dynamical system research is applied to uncover cislunar spatial regions permitting viable transfer arcs. Numerically integrated transfer designs applying low-thrust and a design framework are described.

  20. NASA's Robotic Lunar Lander Development Project

    Science.gov (United States)

    Cohen, Barbara A.

    2012-01-01

    Since early 2005, NASA's Robotic Lunar Lander Development (RLLD) office at NASA MSFC, in partnership with the Applied Physics Laboratory (APL), has developed mission concepts and preformed risk-reduction activities to address planetary science and exploration objectives uniquely met with landed missions. The RLLD team developed several concepts for lunar human-exploration precursor missions to demonstrate precision landing and in-situ resource utilization, a multi-node lunar geophysical network mission, either as a stand-alone mission, or as part of the International Lunar Network (ILN), a Lunar Polar Volatiles Explorer and a Mercury lander mission for the Planetary Science decadal survey, and an asteroid rendezvous and landing mission for the Exploration Precursor Robotics Mission (xPRM) office. The RLLD team has conducted an extensive number of risk-reduction activities in areas common to all lander concepts, including thruster testing, propulsion thermal control demonstration, composite deck design and fabrication, and landing leg stability and vibration. In parallel, the team has developed two robotic lander testbeds providing closed-loop, autonomous hover and descent activities for integration and testing of flight-like components and algorithms. A compressed-air test article had its first flight in September 2009 and completed over 150 successful flights. This small test article (107 kg dry/146 kg wet) uses a central throttleable thruster to offset gravity, plus 3 descent thrusters (37lbf ea) and 6 attitude-control thrusters (12lbf ea) to emulate the flight system with pulsed operation over approximately 10s of flight time. The test article uses carbon composite honeycomb decks, custom avionics (COTS components assembled in-house), and custom flight and ground software. A larger (206 kg dry/322 kg wet), hydrogen peroxide-propelled vehicle began flight tests in spring 2011 and fly over 30 successful flights to a maximum altitude of 30m. The monoprop testbed

  1. Extravehicular Activity Testing in Analog Environments: Evaluating the Effects of Center of Gravity and Environment on Human Performance

    Science.gov (United States)

    Chappell, Steve P.; Gernhardt, Michael L.

    2009-01-01

    Center of gravity (CG) is likely to be an important variable in astronaut performance during partial gravity extravehicular activity (EVA). The Apollo Lunar EVA experience revealed challenges with suit stability and control. The EVA Physiology, Systems and Performance Project (EPSP) in conjunction with the Constellation EVA Systems Project Office have developed plans to systematically understand the role of suit weight, CG and suit pressure on astronaut performance in partial gravity environments. This presentation based upon CG studies seeks to understand the impact of varied CG on human performance in lunar gravity.

  2. Community Report and Recommendations from International Lunar Exploration Working Group (ILEWG)

    Science.gov (United States)

    Foing, Bernard H.

    2016-07-01

    Lunar Network for seismometry and other geophysical measurements - Lunar missions will be driven by exploration, resource utilization, and science; we should consider minimum science payload for every mission, e.g., landers and rovers should carry instruments to determine surface composition and mineralogy - It is felt important to have a shared database about previous missions available for free, so as to provide inputs to future missions, including a gap analysis of needed measurements. Highly resolved global data sets are required. Autonomous landing and hazard avoidance will depend on the best topographic map of the Moon, achievable by combining shared data. - New topics such as life sciences, partial gravity processes on the Moon should be followed in relation to future exploration needs. 2. Technologies and resources - A number of robotic missions to the Moon are now undertaken independently by various nations, with a degree of exchange of information and coordination. That should increase towards real cooperation, still allowing areas of competition for keeping the process active, cost-effective and faster. - Lunar landers, pressurized lunar rover projects as presented from Europe, Asia and America are important steps that can create opportunities for international collaboration, within a coordinated village of robotic precursors and assistants to crew missions. - We have to think about development, modernization of existing navigation capabilities, and provision of lunar positioning, navigation and data relay assets to support future robotic and human exploration. New concepts and new methods for transportation have attracted much attention and are of great potential. 3. Infrastructures and human aspects - It is recommended to have technical sessions and activities dealing with different aspects of human adaptation to space environments, the modeling of sub-systems, microbial protection and use of inflatable technologies - While the Moon is the best and next

  3. A heterogeneous lunar interior for hydrogen isotopes as revealed by the lunar highlands samples

    Science.gov (United States)

    Hui, Hejiu; Guan, Yunbin; Chen, Yang; Peslier, Anne H.; Zhang, Youxue; Liu, Yang; Flemming, Roberta L.; Rossman, George R.; Eiler, John M.; Neal, Clive R.; Osinski, Gordon R.

    2017-09-01

    Knowing the amount and timing of water incorporation into the Moon has fundamental implications for our understanding of how the Earth-Moon system formed. Water has been detected in lunar samples but its abundance, distribution and origin are debated. To address these issues, we report water concentrations and hydrogen isotope ratios obtained by secondary ion mass spectrometry (SIMS) of plagioclase from ferroan anorthosites (FANs), the only available lithology thought to have crystallized directly from the lunar magma ocean (LMO). The measured water contents are consistent with previous results by Fourier transform infrared spectroscopy (FTIR). Combined with literature data, δD values of lunar igneous materials least-degassed at the time of their crystallization range from -280 to + 310 ‰, the latter value being that of FAN 60015 corrected for cosmic ray exposure. We interpret these results as hydrogen isotopes being fractionated during degassing of molecular hydrogen (H2) in the LMO, starting with the magmatic δD value of primordial water at the beginning of LMO being about - 280 ‰, evolving to about + 310 ‰ at the time of anorthite crystallization, i.e. during the formation of the primary lunar crust. The degassing of hydrogen in the LMO is consistent with those of other volatile elements. The wide range of δD values observed in lunar igneous rocks could be due to either various degrees of mixing of the different mantle end members, or from a range of mantle sources that were degassed to different degrees during magma evolution. Degassing of the LMO is a viable mechanism that resulted in a heterogeneous lunar interior for hydrogen isotopes.

  4. Lunar Materials Handling System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Materials Handling System (LMHS) is a method for transfer of lunar soil into and out of process equipment in support of in situ resource utilization...

  5. Lunar Materials Handling System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Materials Handling System (LMHS) is a method for transfer of bulk materials and products into and out of process equipment in support of lunar and Mars in...

  6. Lunar Sulfur Capture System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Sulfur Capture System (LSCS) is an innovative method to recover sulfur compounds from lunar soil using sorbents derived primarily from in-situ resources....

  7. Lunar Sulfur Capture System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Sulfur Capture System (LSCS) is an innovative method to capture greater than 90 percent of sulfur gases evolved during thermal treatment of lunar soils....

  8. Lunar Dust and Lunar Simulant Activation, Monitoring, Solution and Cellular Toxicity Properties

    Science.gov (United States)

    Jeevarajan, A.S.; Wallace, W.T.

    2009-01-01

    During the Apollo missions, many undesirable situations were encountered that must be mitigated prior to returning humans to the moon. Lunar dust (that part of the lunar regolith less than 20 m in diameter) was found to produce several problems with astronaut s suits and helmets, mechanical seals and equipment, and could have conceivably produced harmful physiological effects for the astronauts. For instance, the abrasive nature of the dust was found to cause malfunctions of various joints and seals of the spacecraft and suits. Additionally, though efforts were made to exclude lunar dust from the cabin of the lunar module, a significant amount of material nonetheless found its way inside. With the loss of gravity correlated with ascent of the lunar module from the lunar surface to rendezvous with the command module, much of the major portions of the contaminating soil and dust began to float, irritating the astronaut s eyes and being inhaled into their lungs. Our goal has been to understand some of the properties of lunar dust that could lead to possible hazards for humans. Due to the lack of an atmosphere, there is nothing to protect the lunar soil from ultraviolet radiation, solar wind, and meteorite impacts. These processes could all serve to activate the soil, or produce reactive surface species. In order to understand the possible toxic effects of the reactive dust, it is necessary to reactivate the dust, as samples returned during the Apollo missions were exposed to the atmosphere of the Earth. We have used grinding and UV exposure to mimic some of the processes occurring on the Moon. The level of activation has been monitored using two methods: fluorescence spectroscopy and electron paramagnetic resonance spectroscopy (EPR). These techniques allow the monitoring of hydroxyl radical production in solution. We have found that grinding of lunar dust produces 2-3 times the concentration of hydroxyl radicals as lunar simulant and 10 times that of quartz. Exposure

  9. Quantum gravity

    CERN Document Server

    Kiefer, Claus

    2012-01-01

    The search for a quantum theory of the gravitational field is one of the great open problems in theoretical physics. This book presents a self-contained discussion of the concepts, methods and applications that can be expected in such a theory. The two main approaches to its construction - the direct quantisation of Einstein's general theory of relativity and string theory - are covered. Whereas the first attempts to construct a viable theory for the gravitational field alone, string theory assumes that a quantum theory of gravity will be achieved only through a unification of all the interactions. However, both employ the general method of quantization of constrained systems, which is described together with illustrative examples relevant for quantum gravity. There is a detailed presentation of the main approaches employed in quantum general relativity: path-integral quantization, the background-field method and canonical quantum gravity in the metric, connection and loop formulations. The discussion of stri...

  10. Climate variability according to triple saros gravity cycles

    CERN Document Server

    Livingston, William R

    2013-01-01

    I describe a climate model which corresponds directly to eclipse cycles. The theory is based upon a similarity between the 54 year triple saros eclipse period and the periodicity of drought. I argue that eclipse shadows are an indication of gravity cycles, and that variable lunar gravitation is the most significant aspect of the eclipse process. I reinforce the idea that lunar gravitational forcing has a profound effect on the water vapor in Earth's atmosphere, and can affect the density and location of clouds. I explore the possibility that decadal variability of ocean surface levels may be explained by triple saros gravity cycles. I point out that lunar gravitation was excluded from the most significant climate report of 2007, and that climate data contradictions have been overlooked by researchers. I focus on the value of data that has not been aggregated into global averages. I touch upon the history of global warming, and I offer predictions based upon 54 year climate periodicity.

  11. Lunar Alignments - Identification and Analysis

    Science.gov (United States)

    González-García, A. César

    Lunar alignments are difficult to establish given the apparent lack of written accounts clearly pointing toward lunar alignments for individual temples. While some individual cases are reviewed and highlighted, the weight of the proof must fall on statistical sampling. Some definitions for the lunar alignments are provided in order to clarify the targets, and thus, some new tools are provided to try to test the lunar hypothesis in several cases, especially in megalithic astronomy.

  12. A lunar transportation system

    Science.gov (United States)

    1986-01-01

    Due to large amounts of oxygen required for space travel, a method of mining, transporting, and storing this oxygen in space would facilitate further space exploration. The following project deals specifically with the methods for transporting liquid oxygen from the lunar surface to the Lunar Orbit (LO) space station, and then to the Lower Earth Orbit (LEO) space station. Two vehicles were designed for operation between the LEO and LO space stations. The first of these vehicles is an aerobraked design vehicle. The Aerobrake Orbital Transfer Vehicle (OTV) is capable of transporting 5000 lbm of payload to LO while returning to LEO with 60,000 lbm of liquid oxygen, and thus meet mission requirements. The second vehicle can deliver 18,000 lbm of payload to LO and is capable of bringing 60,000 lbm of liquid oxygen back to LEO. A lunar landing vehicle was also designed for operation between LO and the established moon base. The use of an electromagnetic railgun as a method for launching the lunar lander was also investigated. The feasibility of the railgun is doubtful at this time. A system of spheres was also designed for proper storing and transporting of the liquid oxygen. The system assumes a safe means for transferring the liquid oxygen from tank to tank is operational. A sophisticated life support system was developed for both the OTV and the lunar lander. This system focuses on such factors as the vehicle environment, waste management, water requirements, food requirements, and oxygen requirements.

  13. Lunar Resources: A Review

    CERN Document Server

    Crawford, Ian A

    2014-01-01

    There is growing interest in the possibility that the resource base of the Solar System might in future be used to supplement the economic resources of our own planet. As the Earth's closest celestial neighbour, the Moon is sure to feature prominently in these developments. In this paper I review what is currently known about economically exploitable resources on the Moon, while also stressing the need for continued lunar exploration. I find that, although it is difficult to identify any single lunar resource that will be sufficiently valuable to drive a lunar resource extraction industry on its own (notwithstanding claims sometimes made for the 3He isotope, which I find to be exaggerated), the Moon nevertheless does possess abundant raw materials that are of potential economic interest. These are relevant to a hierarchy of future applications, beginning with the use of lunar materials to facilitate human activities on the Moon itself, and progressing to the use of lunar resources to underpin a future industr...

  14. Formation of Lunar Swirls

    CERN Document Server

    Bamford, R A; Cruz, F; Kellett, B J; Fonseca, R A; Silva, L O; Trines, R M G M; Halekas, J S; Kramer, G; Harnett, E; Cairns, R A; Bingham, R

    2015-01-01

    In this paper we show a plausible mechanism that could lead to the formation of the Dark Lanes in Lunar Swirls, and the electromagnetic shielding of the lunar surface that results in the preservation of the white colour of the lunar regolith. We present the results of a fully self-consistent 2 and 3 dimensional particle-in-cell simulations of mini-magnetospheres that form above the lunar surface and show that they are consistent with the formation of `lunar swirls' such as the archetypal formation Reiner Gamma. The simulations show how the microphysics of the deflection/shielding of plasma operates from a kinetic-scale cavity, and show that this interaction leads to a footprint with sharp features that could be the mechanism behind the generation of `dark lanes'. The physics of mini-magnetospheres is described and shown to be controlled by space-charge fields arising due to the magnetized electrons and unmagnetized ions. A comparison between model and observation is shown for a number of key plasma parameters...

  15. Lunar South Pole space water extraction and trucking system

    Energy Technology Data Exchange (ETDEWEB)

    Zuppero, A. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.]|[Univ. of Idaho, Moscow, ID (United States); Zupp, G. [National Aeronautics and Space Administration, Houston, TX (United States). Johnson Space Center; Schnitzler, B.; Larson, T.K.; Rice, J.W. [Lockheed Martin Idaho Technologies Co., Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab.

    1998-03-01

    This concept proposes to use thermal processes alone to extract water from the lunar South Pole and launch payloads to low lunar orbit. Thermal steam rockets would use water propellant for space transportation. The estimated mass of a space water tanker powered by a nuclear heated steam rocket suggests it can be designed for launch in the Space Shuttle bay. The performance depends on the feasibility of a nuclear reactor rocket engine producing steam at 1,100 degrees Kelvin, with a power density of 150 Megawatts per ton of rocket, and operating for thousands of 20 minute cycles. An example uses reject heat from a small nuclear electric power supply to melt 17,800 tons per year of lunar ice. A nuclear heated steam rocket would use the propellant water to launch and deliver 3,800 tons of water per year to a 100 km low lunar orbit.

  16. A New Double Star Observed During Lunar Occultation: TYC 6312-00761-1

    Science.gov (United States)

    Gault, Dave; Herald, Dave

    2016-10-01

    A lunar occultation observation by DG in March 2013 detected a new, previously unknown companion of star TYC 6312-00761-1. Subsequent lunar occultation observation by DH in September 2015 confirms the double star nature and the two observations when combined gives the solution; Sep = 0.527", PA = 131.59 degrees, at a Mean Date of 2014.45.

  17. Turning on gravity with the Higgs mechanism

    CERN Document Server

    Alexander, Stephon; Magueijo, Joao

    2016-01-01

    We investigate how a Higgs mechanism could be responsible for the emergence of gravity in extensions of Einstein theory. In this scenario, at high energies, symmetry restoration could "turn off" gravity, with dramatic implications for cosmology and quantum gravity. The sense in which gravity is muted depends on the details of the implementation. In the most extreme case gravity's dynamical degrees of freedom would only be unleashed after the Higgs field acquires a non-trivial vacuum expectation value, with gravity reduced to a topological field theory in the symmetric phase. We might also identify the Higgs and the Brans-Dicke fields in such a way that in the unbroken phase Newton's constant vanishes, decoupling matter and gravity. We discuss the broad implications of these scenarios.

  18. MOONLIGHT: A NEW LUNAR LASER RANGING RETROREFLECTOR INSTRUMENT

    Directory of Open Access Journals (Sweden)

    M. Garattini

    2013-12-01

    Full Text Available Since 1969 Lunar Laser Ranging (LLR to the Apollo Cube Corner Reflector (CCR arrays has supplied several significant tests of gravity: Geodetic Precession, the Strong and Weak Equivalence Principle (SEP, WEP, the Parametrized Post Newtonian (PPN parameter , the time change of the Gravitational constant (G, 1/r2 deviations and new gravitational theories beyond General Relativity (GR, like the unified braneworld theory (G. Dvali et al., 2003. Now a new generation of LLR can do better using evolved laser retroreflectors, developed from tight collaboration between my institution, INFN–LNF (Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali di Frascati, and Douglas Currie (University of Maryland, USA, one of the fathers of LLR. The new lunar CCR is developing and characterizing at the “Satellite/Lunar laser ranging Characterization Facility” (SCF, in Frascati, performing our new industry standard space test procedure, the “SCF-Test”; this work contains the experimental results of the SCF-Test applied to the new lunar CCR, and all the new payload developments, including the future SCF tests. The International Lunar Network (ILN research project considers our new retroreflector as one of the possible “Core Instruments”

  19. A lunar polar expedition

    Science.gov (United States)

    Dowling, Richard; Staehle, Robert L.; Svitek, Tomas

    1992-01-01

    Advanced exploration and development in harsh environments require mastery of basic human survival skill. Expeditions into the lethal climates of Earth's polar regions offer useful lessons for tommorrow's lunar pioneers. In Arctic and Antarctic exploration, 'wintering over' was a crucial milestone. The ability to establish a supply base and survive months of polar cold and darkness made extensive travel and exploration possible. Because of the possibility of near-constant solar illumination, the lunar polar regions, unlike Earth's may offer the most hospitable site for habitation. The World Space Foundation is examining a scenario for establishing a five-person expeditionary team on the lunar north pole for one year. This paper is a status report on a point design addressing site selection, transportation, power, and life support requirements.

  20. Chinese Lunar Calendar

    Institute of Scientific and Technical Information of China (English)

    方陵生

    2005-01-01

    @@ Background and Concept The Chinese animal signs2 are a 12-year cycle used for dating the years. They represent a cyclical concept of time, rather than the Western linear concept of time. The Chinese Lunar Calendar is based on the cycles of the moon, and is constructed in a different fashion than the Western solar calendar3. In the Chinese calendar, the beginning of the year falls somewhere between late January and early February. The Chinese have adopted the Western calendar since 1911,but the lunar calendar is still used for festive occasions such as the Chinese New Year. Many Chinese calendars will print both the solar dates and the Chinese lunar dates.

  1. Lunar Sample Compendium

    Science.gov (United States)

    Meyer, C.

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of what has been learned from the study of Apollo and Luna samples of the Moon. Basic information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. Information presented is carefully attributed to the original source publication, thus the Compendium also serves as a ready access to the now vast scientific literature pertaining to lunar smples. The Lunar Sample Compendium is a work in progress (and may always be). Future plans include: adding sections on additional samples, adding new thin section photomicrographs, replacing the faded photographs with newly digitized photos from the original negatives, attempting to correct the age data using modern decay constants, adding references to each section, and adding an internal search engine.

  2. Lunar-A mission: Outline and current status

    Indian Academy of Sciences (India)

    H Mizutani; A Fujimura; S Tanaka; H Shiraishi; T Nakjima

    2005-12-01

    The scientific objective of the Lunar-A,Japanese Penetrator Mission,is to explore the lunar interior by seismic and heat-flow experiments.Two penetrators containing two seismometers (horizontal and vertical components)and heat-flow probes will be deployed from a spacecraft onto the lunar surface,one on the near-side and the other on the far-side of the moon.The data obtained by the penetrators will be transmitted to the earth station via the Lunar-A mother spacecraft orbiting at an altitude of about 200 km. The spacecraft of a cylindrical shape,2.2 m in maximum diameter and 1.7 m in height,is designed to be spin-stabilized.The spacecraft will be inserted into an elliptic lunar orbit,after about a half- year cruise during which complex manoeuvering is made using the lunar-solar gravity assist.After lunar orbit insertion,two penetrators will be separated from the spacecraft near perilune,one by one,and will be landed on the lunar surface. The final impact velocity of the penetrator will be about 285 m/sec;it will encounter a shock of about 8000 G at impact on the lunar surface.According to numerous experimental impact tests using model penetrators and a lunar-regolith analog target,each penetrator is predicted to penetrate to a depth between l and 3 m,depending on the hardness and/or particle-size distribution of the lunar regolith.The penetration depth is important for ensuring the temperature stability of the instruments in the penetrator and heat flow measurements.According to the results of the Apollo heat flow experiment,an insulating regolith blanket of only 30 cm is sufficient to dampen out about 280 K lunar surface temperature fluctuation to > 3K variation. The seismic observations are expected to provide key data on the size of the lunar core,as well as data on deep lunar mantle structure.The heat flow measurements at two penetrator-landing sites will also provide important data on the thermal structure and bulk concentrations of heat- generating

  3. Conceptual analysis of a lunar base transportation system

    Science.gov (United States)

    Hoy, Trevor D.; Johnson, Lloyd B., III; Persons, Mark B.; Wright, Robert L.

    1992-01-01

    Important to the planning for a lunar base is the development of transportation requirements for the establishment and maintenance of that base. This was accomplished as part of a lunar base systems assessment study conducted by the NASA Langley Research Center in conjunction with the NASA Johnson Space Center. Lunar base parameters are presented using a baseline lunar facility concept and timeline of developmental phases. Masses for habitation and scientific modules, power systems, life support systems, and thermal control systems were generated, assuming space station technology as a starting point. The masses were manifested by grouping various systems into cargo missions and interspersing manned flights consistent with construction and base maintenance timelines. A computer program that sizes the orbital transfer vehicles (OTV's), lunar landers, lunar ascenders, and the manned capsules was developed. This program consists of an interative technique to solve the rocket equation successively for each velocity correction (delta V) in a mission. The delta V values reflect integrated trajectory values and include gravity losses. As the program computed fuel masses, it matched structural masses from General Dynamics' modular space-based OTV design. Variables in the study included the operation mode (i.e., expendable vs. reusable and single-stage vs. two-stage OTV's), cryogenic specific impulse, reflecting different levels of engine technology, and aerobraking vs. all-propulsive return to Earth orbit. The use of lunar-derived oxygen was also examined for its general impact. For each combination of factors, the low-Earth orbit (LEO) stack masses and Earth-to-orbit (ETO) lift requirements are summarized by individual mission and totaled for the developmental phase. In addition to these discrete data, trends in the variation of study parameters are presented.

  4. Comparison of Present SST Gravity Field Models

    Institute of Scientific and Technical Information of China (English)

    LUO Jia; SHI Chuang; ZOU Xiancai; WANG Haihong

    2006-01-01

    Taking the main land of Europe as the region to be studied, the potential of the new satellite gravity technique: satellite-to-satellite tracking (SST) and improving the accuracy of regional gravity field model with the SST models are investigated. The drawbacks of these models are discussed. With GPM98C as the reference, the gravity anomaly residuals of several other models, the latest SST global gravity field models (EIGEN series and GGM series), were computed and compared. The results of the comparison show that in the selected region, some systematic errors with periodical properties exist in the EIGEN and GGM's S series models in the high degree and order. Some information that was not shown in the classic gravity models is detected in the low and middle degree and order of EIGEN and GGM's S series models. At last, the effective maximum degrees and orders of SST models are suggested.

  5. Simulating Gravity

    Science.gov (United States)

    Pipinos, Savas

    2010-01-01

    This article describes one classroom activity in which the author simulates the Newtonian gravity, and employs the Euclidean Geometry with the use of new technologies (NT). The prerequisites for this activity were some knowledge of the formulae for a particle free fall in Physics and most certainly, a good understanding of the notion of similarity…

  6. Simulating Gravity

    Science.gov (United States)

    Pipinos, Savas

    2010-01-01

    This article describes one classroom activity in which the author simulates the Newtonian gravity, and employs the Euclidean Geometry with the use of new technologies (NT). The prerequisites for this activity were some knowledge of the formulae for a particle free fall in Physics and most certainly, a good understanding of the notion of similarity…

  7. Academic aspects of lunar water resources and their relevance to lunar protolife.

    Science.gov (United States)

    Green, Jack

    2011-01-01

    Water ice has been discovered on the moon by radar backscatter at the North Pole and by spectrometry at the South Pole in the Cabeus crater with an extrapolated volume for both poles of conservatively 10(9) metric tons. Various exogenic and endogenic sources of this water have been proposed. This paper focuses on endogenic water sources by fumaroles and hot springs in shadowed polar craters. A survey of theoretical and morphological details supports a volcanic model. Release of water and other constituents by defluidization over geological time was intensified in the Hadean Eon (c.a. 4600 to 4000 My). Intensification factors include higher heat flow by now-extinct radionuclides, tidal flexing and higher core temperatures. Lesser gravity would promote deeper bubble nucleation in lunar magmas, slower rise rates of gases and enhanced subsidence of lunar caldera floors. Hadean volcanism would likely have been more intense and regional in nature as opposed to suture-controlled location of calderas in Phanerozoic Benioff-style subduction environments. Seventy-seven morphological, remote sensing and return sample features were categorized into five categories ranging from a volcano-tectonic origin only to impact origin only. Scores for the most logical scenario were 69 to eight in favor of lunar volcanism. Ingredients in the Cabeus plume analysis showed many volcanic fluids and their derivatives plus a large amount of mercury. Mercury-rich fumaroles are well documented on Earth and are virtually absent in cometary gases and solids. There are no mercury anomalies in terrestrial impact craters. Volcanic fluids and their derivatives in lunar shadow can theoretically evolve into protolife. Energy for this evolution can be provided by vent flow charging intensified in the lunar Hadean and by charge separation on freezing fumarolic fluids in shadow. Fischer-Tropsch reactions on hydrothermal clays can yield lipids, polycyclic aromatic hydrocarbons and amino acids. Soluble

  8. Academic Aspects of Lunar Water Resources and Their Relevance to Lunar Protolife

    Directory of Open Access Journals (Sweden)

    Jack Green

    2011-09-01

    Full Text Available Water ice has been discovered on the moon by radar backscatter at the North Pole and by spectrometry at the South Pole in the Cabeus crater with an extrapolated volume for both poles of conservatively 109 metric tons. Various exogenic and endogenic sources of this water have been proposed. This paper focuses on endogenic water sources by fumaroles and hot springs in shadowed polar craters. A survey of theoretical and morphological details supports a volcanic model. Release of water and other constituents by defluidization over geological time was intensified in the Hadean Eon (c.a. 4600 to 4000 My. Intensification factors include higher heat flow by now-extinct radionuclides, tidal flexing and higher core temperatures. Lesser gravity would promote deeper bubble nucleation in lunar magmas, slower rise rates of gases and enhanced subsidence of lunar caldera floors. Hadean volcanism would likely have been more intense and regional in nature as opposed to suture-controlled location of calderas in Phanerozoic Benioff-style subduction environments. Seventy-seven morphological, remote sensing and return sample features were categorized into five categories ranging from a volcano-tectonic origin only to impact origin only. Scores for the most logical scenario were 69 to eight in favor of lunar volcanism. Ingredients in the Cabeus plume analysis showed many volcanic fluids and their derivatives plus a large amount of mercury. Mercury-rich fumaroles are well documented on Earth and are virtually absent in cometary gases and solids. There are no mercury anomalies in terrestrial impact craters. Volcanic fluids and their derivatives in lunar shadow can theoretically evolve into protolife. Energy for this evolution can be provided by vent flow charging intensified in the lunar Hadean and by charge separation on freezing fumarolic fluids in shadow. Fischer-Tropsch reactions on hydrothermal clays can yield lipids, polycyclic aromatic hydrocarbons and amino

  9. Simulating the star tracks in the field of view of the Lunar polar telescope of the ILOM project in dependence on the Lunar dynamical figure

    Science.gov (United States)

    Petrova, N.; Gusev, A.

    2009-04-01

    The measurement of the rotation of the Moon is one of techniques to get the information of the internal structure of celestial body. The Lunar Laser Ranging (LLR) has given unprecedented data on the lunar rotation, and gives some proposals of the state of the core. In situ Lunar Orientation Measurement (ILOM) is an experiment to measure the lunar physical librations in situ on the Moon with a small telescope which tracks stars. Simulating the trajectory of stars due to the lunar rotation observed by the ILOM-telescope in the polar region was already made by using numerical theory DE405 (Noda et al., 2008). We have executed calculations of libration tracks of stars on the basis of analytical libration theory (Petrova, 1996; Chapront et al, 1999). It allowed us to do simulating for various models of Lunar gravity field (Lunar dynamical figure). We used dynamical figures constructed on the basis of data received in the current mission Kaguya (SELENE), and then we compared the results with calculations with other dynamic models constructed on the data obtained by the Clementine (GLGM-2) and the Lunar Prospector (LP150Q). The differences between the models GLGM-2, LP150Q and the Kaguya model are larger than 10 milliseconds of arc. This means that proposed accuracy of ILOM observations - 1 millisecond of arc will be enough to improve many parameters of the Lunar interior. In particular, residual estimations will allow to detect small amplitudes of free libration caused by a liquid Lunar core and to estimate its characteristic, first of all - core's ellipticity. All calculation and comparisons, graphic presentation were executed in the VBA environment for MS Excel. The research was supported by the Russian-Japanese grant RFFI-JSPS N 07-02-91212, (2007 - 2009).

  10. Ground Reaction Forces During Reduced Gravity Running in Parabolic Flight.

    Science.gov (United States)

    Cavanagh, Peter; Rice, Andrea; Glauberman, Molly; Sudduth, Amanda; Cherones, Arien; Davis, Shane; Lewis, Michael; Hanson, Andrea; Wilt, Grier

    2017-08-01

    Treadmills have been employed as both a form of exercise and a countermeasure to prevent changes in the musculoskeletal system on almost all NASA missions and many Russian missions since the early Space Shuttle flights. It is possible that treadmills may also be part of exercise programs on future Mars missions and that they may be a component of exercise facilities in lunar or Martian habitats. In order to determine if the ambient gravity on these destinations will provide osteogenic effects while performing exercise on a treadmill, ground reactions forces (GRFs) were measured on eight subjects (six women and two men) running at 6 mph during parabolic flight in Martian and lunar gravity conditions. On average, stride length increased as gravity decreased. The first and second peaks of the GRFs decreased by 0.156 and 0.196 bodyweights, respectively, per 1/10 g change in ambient gravity. Based on comparisons with previously measured GRF during loaded treadmill running on the International Space Station, we conclude that unloaded treadmill running under lunar and Martian conditions during exploration missions is not likely to be an osteo-protective exercise.Cavanagh P, Rice A, Glauberman M, Sudduth A, Cherones A, Davis S, Lewis M, Hanson A, Wilt G. Ground reaction forces during reduced gravity running in parabolic flight. Aerosp Med Hum Perform. 2017; 88(8):730-736.

  11. Measuring Gravity in International Trade Flows

    Directory of Open Access Journals (Sweden)

    E. Young Song

    2004-12-01

    Full Text Available The purpose of this paper is two-fold. One is to clarify the concept of gravity in international trade flows. The other is to measure the strength of gravity in international trade flows in a way that is consistent with a well-defined concept of gravity. This paper shows that the widely accepted belief that specialization is the source of gravity is not well grounded on theory. We propose to define gravity in international trade as the force that makes the market shares of an exporting country constant in all importing countries, regardless of their sizes. In a stochastic context, we should interpret it as implying that the strength of gravity increases i as the correlation between market shares and market sizes gets weaker and ii as the variance of market shares gets smaller. We estimate an empirical gravity equation thoroughly based on this definition of gravity. We find that a strong degree of gravity exists in most bilateral trade, regardless of income levels of countries, and in trade of most manThe purpose of this paper is two-fold. One is to clarify the concept of gravity in international trade flows. The other is to measure the strength of gravity in international trade flows in a way that is consistent with a well-defined concept of gravity. This paper shows that the widely accepted belief that specialization is the source of gravity is not well grounded on theory. We propose to define gravity in international trade as the force that makes the market shares of an exporting country constant in all importing countries, regardless of their sizes. In a stochastic context, we should interpret it as implying that the strength of gravity increases i as the correlation between market shares and market sizes gets weaker and ii as the variance of market shares gets smaller. We estimate an empirical gravity equation thoroughly based on this definition of gravity. We find that a strong degree of gravity exists in most bilateral trade, regardless of

  12. Stochastic gravity: beyond semiclassical gravity

    Energy Technology Data Exchange (ETDEWEB)

    Verdaguer, E [Departament de Fisica Fonamental and CER en Astrofisica, Fisica de Particules i Cosmologia, Universitat de Barcelona, Av. Diagonal 647, 08028 Barcelona (Spain)

    2007-05-15

    The back-reaction of a classical gravitational field interacting with quantum matter fields is described by the semiclassical Einstein equation, which has the expectation value of the quantum matter fields stress tensor as a source. The semiclassical theory may be obtained from the quantum field theory of gravity interacting with N matter fields in the large N limit. This theory breaks down when the fields quantum fluctuations are important. Stochastic gravity goes beyond the semiclassical limit and allows for a systematic and self-consistent description of the metric fluctuations induced by these quantum fluctuations. The correlation functions of the metric fluctuations obtained in stochastic gravity reproduce the correlation functions in the quantum theory to leading order in an 1/N expansion. Two main applications of stochastic gravity are discussed. The first, in cosmology, to obtain the spectrum of primordial metric perturbations induced by the inflaton fluctuations, even beyond the linear approximation. The second, in black hole physics, to study the fluctuations of the horizon of an evaporating black hole.

  13. The Sooner Lunar Schooner: Lunar engineering education

    Science.gov (United States)

    Miller, D. P.; Hougen, D. F.; Shirley, D.

    2003-06-01

    The Sooner Lunar Schooner is a multi-disciplinary ongoing project at the University of Oklahoma to plan, design, prototype, cost and (when funds become available) build/contract and fly a robotic mission to the Moon. The goal of the flight will be to explore a small section of the Moon; conduct a materials analysis of the materials left there by an Apollo mission thirty years earlier; and to perform a selenographic survey of areas that were too distant or considered too dangerous to be done by the Apollo crew. The goal of the Sooner Lunar Schooner Project is to improve the science and engineering educations of the hundreds of undergraduate and graduate students working on the project. The participants, while primarily from engineering and physics, will also include representatives from business, art, journalism, law and education. This project ties together numerous existing research programs at the University, and provides a framework for the creation of many new research proposals. The authors were excited and motivated by the Apollo missions to the Moon. When we asked what we could do to similarly motivate students we realized that nothing is as exciting as going to the Moon. The students seem to agree.

  14. Lunar magma transport phenomena

    Science.gov (United States)

    Spera, Frank J.

    1992-01-01

    An outline of magma transport theory relevant to the evolution of a possible Lunar Magma Ocean and the origin and transport history of the later phase of mare basaltic volcanism is presented. A simple model is proposed to evaluate the extent of fractionation as magma traverses the cold lunar lithosphere. If Apollo green glasses are primitive and have not undergone significant fractionation en route to the surface, then mean ascent rates of 10 m/s and cracks of widths greater than 40 m are indicated. Lunar tephra and vesiculated basalts suggest that a volatile component plays a role in eruption dynamics. The predominant vapor species appear to be CO CO2, and COS. Near the lunar surface, the vapor fraction expands enormously and vapor internal energy is converted to mixture kinetic energy with the concomitant high-speed ejection of vapor and pyroclasts to form lunary fire fountain deposits such as the Apollo 17 orange and black glasses and Apollo 15 green glass.

  15. Lunar Phases Planisphere

    Science.gov (United States)

    Shawl, Stephen J.

    2010-01-01

    This paper describes a lunar phases planisphere with which a user can answer questions about the rising and setting times of the Moon as well as questions about where the Moon will be at a given phase and time. The article contains figures that can be photocopied to make the planisphere. (Contains 2 figures.)

  16. Lunar troilite: Crystallography

    Science.gov (United States)

    Evans, H.T.

    1970-01-01

    Fine, euhedral crystals of troilite from lunar sample 10050 show a hexagonal habit consistent with the high-temperature NiAs-type structure. Complete three-dimensional counter intensity data have been measured and used to confirm and refine Bertaut's proposed low-temperature crystal structure.

  17. Revised Thickness of the Lunar Crust from GRAIL Data: Implications for Lunar Bulk Composition

    Science.gov (United States)

    Taylor, G. Jeffrey; Wieczorek, Mark A.; Neumann, Gregory A.; Nimmo, Francis; Kiefer, Walter S.; Melosh, H. Jay; Phillips, Roger J.; Solomon, Sean C.; Andrews-Hanna, Jeffrey C.; Asmar, Sami W.; Konopliv, Alexander S.; Lemoine, Frank G.; Smith, David E.; Watkins, Michael W.; Williams, James G.; Zuber, Maria T.

    2013-01-01

    High-resolution gravity data from GRAIL have yielded new estimates of the bulk density and thickness of the lunar crust. The bulk density of the highlands crust is 2550 kg m-3. From a comparison with crustal composition measured remotely, this density implies a mean porosity of 12%. With this bulk density and constraints from the Apollo seismic experiment, the average global crustal thickness is found to lie between 34 and 43 km, a value 10 to 20 km less than several previous estimates. Crustal thickness is a central parameter in estimating bulk lunar composition. Estimates of the concentrations of refractory elements in the Moon from heat flow, remote sensing and sample data, and geophysical data fall into two categories: those with refractory element abundances enriched by 50% or more relative to Earth, and those with abundances the same as Earth. Settling this issue has implications for processes operating during lunar formation. The crustal thickness resulting from analysis of GRAIL data is less than several previous estimates. We show here that a refractory-enriched Moon is not required

  18. FLARE: The Far Side Lunar Research Expedition. A design of a far side lunar observatory

    Science.gov (United States)

    Bishop, David W.; Chakrabarty, Rudhmala P.; Hannula, Dawn M.; Hargus, William A., Jr.; Melendrez, A. Dean; Niemann, Christopher J.; Neuenschwander, Amy L.; Padgett, Brett D.; Patel, Sanjiv R.; Wiesehuegel, Leland J.

    1991-12-01

    This document outlines the design completed by members of Lone Star Aerospace, Inc. (L.S.A.) of a lunar observatory on the far side of the Moon. Such a base would not only establish a long term human presence on the Moon, but would also allow more accurate astronomical data to be obtained. A lunar observatory is more desirable than an Earth based observatory for the following reasons: instrument weight is reduced due to the Moon's weaker gravity; near vacuum conditions exist on the Moon; the Moon has slow rotation to reveal the entire sky; and the lunar surface is stable for long baseline instruments. All the conditions listed above are favorable for astronomical data recording. The technical aspects investigated in the completion of this project included site selection, mission scenario, scientific instruments, communication and power systems, habitation and transportation, cargo spacecraft design, thermal systems, robotic systems, and trajectory analysis. The site selection group focused its efforts on finding a suitable location for the observatory. Hertzsprung, a large equatorial crater on the eastern limb, was chosen as the base site.

  19. U.S. Isostatic Residual Gravity Grid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — isores.bin - standard grid containing isostatic residual gravity map for U.S. Grid interval = 4 km. Projection is Albers (central meridian = 96 degrees West; base...

  20. On Applications of Selenodesy to Lunar Detection

    Institute of Scientific and Technical Information of China (English)

    WEI Erhu; LIU Jingnan

    2006-01-01

    According to the history of lunar detection, the relationship between selenodesy and lunar detection is reviewed , and the focus of the lunar detection and the lunar detection plan of China are summarized. The key techniques of selenodesy are presented, and the applications of selenodesy to the lunar detection are discussed.

  1. The loop gravity string

    CERN Document Server

    Freidel, Laurent; Pranzetti, Daniele

    2016-01-01

    In this work we study canonical gravity in finite regions for which we introduce a generalisation of the Gibbons-Hawking boundary term including the Immirzi parameter. We study the canonical formulation on a spacelike hypersuface with a boundary sphere and show how the presence of this term leads to an unprecedented type of degrees of freedom coming from the restoration of the gauge and diffeomorphism symmetry at the boundary. In the presence of a loop quantum gravity state, these boundary degrees of freedom localize along a set of punctures on the boundary sphere. We demonstrate that these degrees of freedom are effectively described by auxiliary strings with a 3-dimensional internal target space attached to each puncture. We show that the string currents represent the local frame field, that the string angular momenta represent the area flux and that the string stress tensor represents the two dimensional metric on the boundary of the region of interest. Finally, we show that the commutators of these broken...

  2. Integration of Apollo Lunar Sample Data into Google Moon

    Science.gov (United States)

    Dawson, Melissa D.; Todd, Nancy S.; Lofgren, Gary

    2010-01-01

    The Google Moon Apollo Lunar Sample Data Integration project is a continuation of the Apollo 15 Google Moon Add-On project, which provides a scientific and educational tool for the study of the Moon and its geologic features. The main goal of this project is to provide a user-friendly interface for an interactive and educational outreach and learning tool for the Apollo missions. Specifically, this project?s focus is the dissemination of information about the lunar samples collected during the Apollo missions by providing any additional information needed to enhance the Apollo mission data on Google Moon. Apollo missions 15 and 16 were chosen to be completed first due to the availability of digitized lunar sample photographs and the amount of media associated with these missions. The user will be able to learn about the lunar samples collected in these Apollo missions, as well as see videos, pictures, and 360 degree panoramas of the lunar surface depicting the lunar samples in their natural state, following collection and during processing at NASA. Once completed, these interactive data layers will be submitted for inclusion into the Apollo 15 and 16 missions on Google Moon.

  3. The International Lunar Decade Declaration

    Science.gov (United States)

    Beldavs, V.; Foing, B.; Bland, D.; Crisafulli, J.

    2015-10-01

    The International Lunar Decade Declaration was discussed at the conference held November 9-13, 2014 in Hawaii "The Next Giant Leap: Leveraging Lunar Assets for Sustainable Pathways to Space" - http://2014giantleap.aerospacehawaii.info/ and accepted by a core group that forms the International Lunar Decade Working Group (ILDWG) that is seeking to make the proposed global event and decade long process a reality. The Declaration will be updated from time to time by members of the ILDWreflecting new knowledge and fresh perspectives that bear on building a global consortium with a mission to progress from lunar exploration to the transformation of the Moon into a wealth gene rating platform for the expansion of humankind into the solar system. When key organizations have endorsed the idea and joined the effort the text of the Declaration will be considered final. An earlier International Lunar Decade proposal was issued at the 8th ICEUM Conference in 2006 in Beijing together with 13 specific initiatives for lunar exploration[1,2,3]. These initiatives have been largely implemented with coordination among the different space agencies involved provided by the International Lunar Exploration Working Group[2,3]. The Second International Lunar Decade from 2015 reflects current trends towards increasing involvement of commercial firms in space, particularly seeking opportunities beyond low Earth orbit. The central vision of the International Lunar Decade is to build the foundations for a sustainable space economy through international collaboration concurrently addressing Lunar exploration and building a shared knowledge base;Policy development that enables collabo rative research and development leading to lunar mining and industrial and commercial development;Infrastructure on the Moon and in cislunar space (communications, transport, energy systems, way-stations, other) that reduces costs, lowers risks and speeds up the time to profitable operations;Enabling technologies

  4. Lunar Imaging and Ionospheric Calibration for the Lunar Cherenkov Technique

    CERN Document Server

    McFadden, Rebecca; Mevius, Maaijke

    2013-01-01

    The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the ionosphere is an important experimental concern as it reduces the pulse amplitude and subsequent chances of detection. We are continuing to investigate a new method to calibrate the dispersive effect of the ionosphere on lunar Cherenkov pulses via Faraday rotation measurements of the Moon's polarised emission combined with geomagnetic field models. We also extend this work to include radio imaging of the Lunar surface, which provides information on the physical and chemical properties of the lunar surface that may affect experimental strategies for the lunar Cherenkov technique.

  5. GRAIL gravity field determination using the Celestial Mechanics Approach - status report

    Science.gov (United States)

    Bertone, S.; Arnold, D.; Jäggi, A.; Beutler, G.; Mervart, L.

    2015-10-01

    The NASA mission GRAIL (Gravity Recovery And Interior Laboratory [1]) inherits its concept from the GRACE (Gravity Recovery And Climate Experiment)mission to determine the gravity field of the Moon. The use of inter-satellite Ka-band range-rate (KBRR) observations enables data aquisition even when the spacecraft are not tracked from the Earth [2]. The data allows for a highly accurate estimation of the lunar gravity field on both sides of the Moon, which is crucial to improve the understanding of its internal structure and thermal evolution. In this presentation we dis- cuss our latest GRAIL-based lunar gravity fields generated with the Celestial Mechanics Approach using the Bernese Software.

  6. 基于综合法的重力坝整体稳定性安全度分析%An Overall Stability Analysis of the Safety Degree of Gravity Dams Based on Synthesis Method

    Institute of Scientific and Technical Information of China (English)

    胡海周; 彭刚; 周洪涛; 谢玖杨

    2012-01-01

    According to the plastic strain energy and the yield zone through two mutation criteria,by using the ABAQUS finite element software and the synthesis method of overloading after a strong first falling,this paper analyzes the overall stability of gravity dams.Our analysis shows that the overall stability of gravity dams will be more suitable when we use the integrated method and set the initial strength reduction factor of 1.30.The bigger the strength reduction factor is,the bigger the overall safety factor will be.%采用ABAQUS有限元软件,利用先降强后超载的综合法、依据塑性应变能和屈服区贯通两种突变性判据对重力坝进行整体稳定性分析。分析表明:采用综合法时,初始强度折减系数为1.3分析重力坝整体稳定性比较适合;初始强度折减系数较大,综合安全系数也较大。

  7. Lunar Solar Power System and Lunar Exploration

    Science.gov (United States)

    Criswell, D. R.

    2002-01-01

    Five of the six billion people on Earth produce less than 2,500 per year per person of Gross World Product (GWP). GWP growth is severely limited by the high cost, low availability and reliability, environmental damages, and political uncertainties of conventional fossil, nuclear, and terrestrial renewable power systems. In 2000 the World Energy Council challenged all decision makers to enable the equivalent of 6.7 kWt per person of thermal power within two generations. This implies 67 TWt, or approx.20 to 30 TWe, of sustainable electric power by 2050. Twenty-five power systems were reviewed to select which could: (1) sustainably provide 20 TWe to consumers; (2) profitably sell electricity for less than 0.01 per kWe-h; (3) be environmentally neutral, even nurturing; and (4) use understood technologies. The analyses indicated that only the Lunar Solar Power (LSP) System could meet these requirements within the 21st Century.

  8. Mineralogical studies of lunar meteorites and their lunar analogs

    Science.gov (United States)

    Takeda, H.; Mori, H.; Miyamoto, M.; Ishii, T.

    1985-01-01

    The minerology and textural properties of three lunar meteorites (Yamato 791197, ALH81005, and Yamato 82192) were analyzed and compared with lunar surface rock samples. The chemical composition and textures of pyroxene and the occurrance of glass matrices were specifically addressed. The study of glass in the lunar meteorites suggests that the glass was not produced by a meteorite impact which excavated the mass into orbit towards the Earth. The glass had been devitrified on the lunar surface before the excavation, and new glass was not produced by the last impact.

  9. Self Completeness of Einstein Gravity

    CERN Document Server

    Dvali, Gia

    2010-01-01

    We argue, that in Einsteinian gravity the Planck length is the shortest length of nature, and any attempt of resolving trans-Planckian physics bounces back to macroscopic distances due to black hole formation. In Einstein gravity trans-Planckian propagating quantum degrees of freedom cannot exist, instead they are equivalent to the classical black holes that are fully described by lighter infra-red degrees of freedom and give exponentially-soft contribution into the virtual processes. Based on this property we argue that pure-Einstein (super)gravity and its high-dimensional generalizations are self-complete in deep-UV, but not in standard Wilsonian sense. We suggest that certain strong-coupling limit of string theory is built-in in pure Einstein gravity, whereas the role of weakly-coupled string theory limit is to consistently couple gravity to other particle species, with their number being set by the inverse string coupling. We also discuss some speculative ideas generalizing the notion of non-Wilsonian sel...

  10. On the spectral combination of satellite gravity model, terrestrial and airborne gravity data for local gravimetric geoid computation

    Science.gov (United States)

    Jiang, Tao; Wang, Yan Ming

    2016-12-01

    One of the challenges for geoid determination is the combination of heterogeneous gravity data. Because of the distinctive spectral content of different data sets, spectral combination is a suitable candidate for its solution. The key to have a successful combination is to determine the proper spectral weights, or the error degree variances of each data set. In this paper, the error degree variances of terrestrial and airborne gravity data at low degrees are estimated by the aid of a satellite gravity model using harmonic analysis. For higher degrees, the error covariances are estimated from local gravity data first, and then used to compute the error degree variances. The white and colored noise models are also used to estimate the error degree variances of local gravity data for comparisons. Based on the error degree variances, the spectral weights of satellite gravity models, terrestrial and airborne gravity data are determined and applied for geoid computation in Texas area. The computed gravimetric geoid models are tested against an independent, highly accurate geoid profile of the Geoid Slope Validation Survey 2011 (GSVS11). The geoid computed by combining satellite gravity model GOCO03S and terrestrial (land and DTU13 altimetric) gravity data agrees with GSVS11 to ±1.1 cm in terms of standard deviation along a line of 325 km. After incorporating the airborne gravity data collected at 11 km altitude, the standard deviation is reduced to ±0.8 cm. Numerical tests demonstrate the feasibility of spectral combination in geoid computation and the contribution of airborne gravity in an area of high quality terrestrial gravity data. Using the GSVS11 data and the spectral combination, the degree of correctness of the error spectra and the quality of satellite gravity models can also be revealed.

  11. Testing Lorentz symmetry with Lunar Laser Ranging

    CERN Document Server

    Bourgoin, A; Bouquillon, S; Poncin-Lafitte, C Le; Francou, G; Angonin, M -C

    2016-01-01

    Lorentz symmetry violations can be parametrized by an effective field theory framework that contains both General Relativity (GR) and the Standard Model of particle physics called the Standard-Model Extension (SME). We present new constraints on pure gravity SME coefficients obtained by analyzing Lunar Laser Ranging (LLR) observations. We use a new numerical lunar ephemeris computed in the SME framework and we perform a LLR data analysis using a set of 20721 normal points covering the period August 1969 to December 2013. We emphasize that linear combination of SME coefficients to which LLR data are sensitive are not the same as those fitted in previous post-fit residuals analysis using LLR observations and based on theoretical grounds. We found no evidence for Lorentz violation at the level of $10^{-8}$ for $\\bar{s}^{TX}$, $10^{-12}$ for $\\bar{s}^{XY}$ and $\\bar{s}^{XZ}$, $10^{-11}$ for $\\bar{s}^{XX}-\\bar{s}^{YY}$ and $\\bar{s}^{XX}+\\bar{s}^{YY}-2\\bar{s}^{ZZ}-0.045\\bar{s}^{YZ}$ and $10^{-9}$ for $\\bar{s}^{TY}+...

  12. Testing Lorentz Symmetry with Lunar Laser Ranging

    Science.gov (United States)

    Bourgoin, A.; Hees, A.; Bouquillon, S.; Le Poncin-Lafitte, C.; Francou, G.; Angonin, M.-C.

    2016-12-01

    Lorentz symmetry violations can be parametrized by an effective field theory framework that contains both general relativity and the standard model of particle physics called the standard-model extension (SME). We present new constraints on pure gravity SME coefficients obtained by analyzing lunar laser ranging (LLR) observations. We use a new numerical lunar ephemeris computed in the SME framework and we perform a LLR data analysis using a set of 20 721 normal points covering the period of August, 1969 to December, 2013. We emphasize that linear combination of SME coefficients to which LLR data are sensitive and not the same as those fitted in previous postfit residuals analysis using LLR observations and based on theoretical grounds. We found no evidence for Lorentz violation at the level of 10-8 for s¯T X, 10-12 for s¯X Y and s¯X Z, 10-11 for s¯X X-s¯Y Y and s¯X X+s¯Y Y-2 s¯Z Z-4.5 s¯Y Z, and 10-9 for s¯T Y+0.43 s¯T Z. We improve previous constraints on SME coefficient by a factor up to 5 and 800 compared to postfit residuals analysis of respectively binary pulsars and LLR observations.

  13. LANTR Engine Optimization for Lunar Missions

    Science.gov (United States)

    Bulman, M. J.; Poth, Greg; Borowski, Stan

    2006-01-01

    Propulsion requirements for sustainable Lunar missions are very demanding. The high Delta V for short transit times and/or reusable vehicles are best served with the High Isp of Nuclear Propulsion. High thrust is needed to reduce gravity losses during earth departure. The LOX-Augmented Nuclear Thermal Rocket (LANTR) is a concept whereby thrust from a nuclear thermal rocket can be doubled, or even quadrupled, by the injection and combustion of gaseous oxygen downstream of the throat. This has many advantages for the mission including a reduction in the size of the reactor(s) and propellant tank volume for a given payload delivered to Low Lunar Orbit. In this paper, we conduct mission studies to define the optimum basic (Unaugmented) engine thrust, Lox augmentation level and Lox loading for minimum initial mass in low earth orbit. 35% mass savings are seen for NTR powered LTVs with over twice the propellant Volume. The LANTR powered LTV has a similar mass savings with minimal volume penalties.

  14. Lunar Health Monitor (LHM)

    Science.gov (United States)

    Lisy, Frederick J.

    2015-01-01

    Orbital Research, Inc., has developed a low-profile, wearable sensor suite for monitoring astronaut health in both intravehicular and extravehicular activities. The Lunar Health Monitor measures respiration, body temperature, electrocardiogram (EKG) heart rate, and other cardiac functions. Orbital Research's dry recording electrode is central to the innovation and can be incorporated into garments, eliminating the need for conductive pastes, adhesives, or gels. The patented dry recording electrode has been approved by the U.S. Food and Drug Administration. The LHM is easily worn under flight gear or with civilian clothing, making the system completely versatile for applications where continuous physiological monitoring is needed. During Phase II, Orbital Research developed a second-generation LHM that allows sensor customization for specific monitoring applications and anatomical constraints. Evaluations included graded exercise tests, lunar mission task simulations, functional battery tests, and resting measures. The LHM represents the successful integration of sensors into a wearable platform to capture long-duration and ambulatory physiological markers.

  15. Lunar hand tools

    Science.gov (United States)

    Bentz, Karl F.; Coleman, Robert D.; Dubnik, Kathy; Marshall, William S.; Mcentee, Amy; Na, Sae H.; Patton, Scott G.; West, Michael C.

    1987-01-01

    Tools useful for operations and maintenance tasks on the lunar surface were determined and designed. Primary constraints are the lunar environment, the astronaut's space suit and the strength limits of the astronaut on the moon. A multipurpose rotary motion tool and a collapsible tool carrier were designed. For the rotary tool, a brushless motor and controls were specified, a material for the housing was chosen, bearings and lubrication were recommended and a planetary reduction gear attachment was designed. The tool carrier was designed primarily for ease of access to the tools and fasteners. A material was selected and structural analysis was performed on the carrier. Recommendations were made about the limitations of human performance and about possible attachments to the torque driver.

  16. The Lunar Sample Compendium

    Science.gov (United States)

    Meyer, Charles

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of the data obtained from 40 years of study of Apollo and Luna samples of the Moon. Basic petrographic, chemical and age information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. The LSC can be found online using Google. The initial allocation of lunar samples was done sparingly, because it was realized that scientific techniques would improve over the years and new questions would be formulated. The LSC is important because it enables scientists to select samples within the context of the work that has already been done and facilitates better review of proposed allocations. It also provides back up material for public displays, captures information found only in abstracts, grey literature and curatorial databases and serves as a ready access to the now-vast scientific literature.

  17. The Lunar Sample Compendium

    Science.gov (United States)

    Meyer, Charles

    2009-01-01

    The Lunar Sample Compendium is a succinct summary of the data obtained from 40 years of study of Apollo and Luna samples of the Moon. Basic petrographic, chemical and age information is compiled, sample-by-sample, in the form of an advanced catalog in order to provide a basic description of each sample. The LSC can be found online using Google. The initial allocation of lunar samples was done sparingly, because it was realized that scientific techniques would improve over the years and new questions would be formulated. The LSC is important because it enables scientists to select samples within the context of the work that has already been done and facilitates better review of proposed allocations. It also provides back up material for public displays, captures information found only in abstracts, grey literature and curatorial databases and serves as a ready access to the now-vast scientific literature.

  18. Lunar base initiative 1992

    Science.gov (United States)

    Koelle, H. H.

    The return to the Moon is no longer a question of yes or no, but a question of when and how. The first landing of a human being on the lunar surface in 1969 was a purely national effort of the U.S.A. Building a lunar base and operating it in the next century is rather a task for all nations of this planet, even if one nation could do it alone. However, there are several alternatives to carry out such a program and these will and should be debated during the next years on an urgent basis. To do this, one has to take into account not only the historical accomplishments and the present trends of cooperation in space programs, but also recent geopolitical developments as well as the frame of reference established by international law. The case for an International Lunar Base (ILB) has been presented to the International Academy of Astronautics on 11 October 1987 by the IAA Ad Hoc Committee "Return-to-the-Moon". This draft of a position paper was subsequently published in Acta Astronautica Vol. 17, No. 5, (pp. 463-489) with the request of public debate particularly by the members of the Academy. Some 80 Academicians responded to this invitation by the President of the Academy and voiced their opinions on the questions and issues raised by this draft of a position paper. This led to a refinement of the arguments and assumptions made and it is now possible to prepare an improved position paper proposing concrete steps which may lead to an ILB. An issue of this proportion must start with a discussion of goals and objectives to be arranged in some kind of a ranked order. It also has to take note of the limitations existing at any time by the availability of suitable space transportation systems. These will determine the acquisition date and rate of growth of a lunar base. The logistics system will also greatly influence the base characteristics and layout. The availability of heavy lift launch vehicles would simplify the task and allow to concentrate the construction

  19. Measuring and distinguishing compositional and maturity properties of lunar soils by remote VIS-NIR spectroscopy

    Science.gov (United States)

    Fischer, Erich M.; Pieters, Carle M.

    1993-03-01

    Space weathering on the lunar surface affects the spectra/optical character of an exposed lunar soil in three ways: the reflectance is reduced, absorption band depths are reduced, and a red-sloped continuum is created and increased with exposure. As a result, the spectrum of a lunar soil is dependent upon both the degree of exposure at the lunar surface and the original composition. It is critical to the remote analysis of lunar soils to differentiate between the optical effects of maturity and the effects of composition. In the laboratory, it is possible to determine and consequently distinguish the degree of exposure, or soil maturity, as measured by parameters such as Is/FeO (e.g., 1; mature defined as Is/FeO greater than or equal to 60), and the composition, as measured by various chemical and petrographical techniques. Lunar soils returned by the Apollo missions provide important ground truth for developing methods for remotely measuring the maturity and the concentration of Fe-bearing minerals in lunar soil. The ground truth spectral data analyzed are from the John Adams lunar soil spectra collection. Soils collected from or near highland terrains are emphasized in the discussion. The mineralogical makeup of mare soils results in behavior somewhat different from highland soils.

  20. Speciation and dissolution of hydrogen in the proto-lunar disk

    CERN Document Server

    Pahlevan, Kaveh; Fegley, Bruce

    2016-01-01

    Despite very high temperatures accompanying lunar origin, indigenous water in the form of OH has been unambiguously observed in Apollo samples in recent years. Such observations have prompted questions about the abundance and distribution of lunar hydrogen. Here, we investigate the related question of the origin of lunar H: is the hydrogen observed a remnant of a much larger initial inventory that was inherited from a wet Earth but partly depleted during the process of origin, or was hydrogen quantitatively lost from the lunar material, with water being delivered to lunar reservoirs via subsequent impacts after the origins sequence? Motivated by recent results pointing to a limited extent of hydrogen escape from the gravity field of the Earth during lunar origin, we apply a newly developed thermodynamic model of liquid-vapor silicates to the proto-lunar disk to interrogate the behavior of H as a trace element in the energetic aftermath of the giant impact. We find that: (1) pre-existing H-bearing molecules ar...

  1. A geotechnical characterization of lunar soils and lunar soil simulants

    Science.gov (United States)

    Graf, John Carl

    Many of the essential materials needed for the construction of a lunar base can be produced from the resources found on the lunar surface. Processing natural resources on the moon into useful products will reduce the need, and the cost, to bring everything from earth. The lunar regolith has been intensely studied with respect to understanding the formation of the moon and the earth, but as a construction material, the regolith is poorly characterized and poorly understood. To better understand how to 'work' with the lunar regolith, four loosely related research projects were conducted. Two projects relate to characterizing and understanding the geotechnical properties of regolith, two projects relate to manipulating and processing granular materials in the lunar environment. The shapes of lunar soil grains are characterized using fractals - results directly and quantitatively describe the rugged reentrant nature of the large scale structure and the relatively smooth surface texture of lunar soil grains. The nature of lunar soil cohesion is considered using tensile strength measurements of lunar soil simulant. It is likely that mechanical interlocking of irregular grains is the primary cause of lunar soil cohesion. This mechanism is highly sensitive to grain shape, but relatively insensitive to particle packing density. A series of experiments are conducted to try to understand how granular particles might sort by size in a vacuum. Even in a vacuum, fine particle subjected to shear strain segregate by a mechanism called the random fluctuating sieve The random fluctuating sieve also controls particle motion that determines the structure of wind-blown sand ripples. Hybrid microwave heating was used to sinter large structural bricks from lunar soil stimulant. While heating was prone to thermal runaway, microwave heating holds great promise as a simple, direct method of making sintered structural bricks.

  2. Lunar science: An overview

    Indian Academy of Sciences (India)

    Stuart Ross Taylor

    2005-12-01

    Before spacecraft exploration,facts about the Moon were restricted to information about the lunar orbit,angular momentum and density.Speculations about composition and origin were unconstrained.Naked eye and telescope observations revealed two major terrains,the old heavily cratered highlands and the younger mostly circular,lightly cratered maria.The lunar highlands were thought to be composed of granite or covered with volcanic ash-flows.The maria were thought to be sediments,or were full of dust,and possibly only a few million years old.A few perceptive observers such as Ralph Baldwin (Baldwin 1949)concluded that the maria were filled with volcanic lavas, but the absence of terrestrial-type central volcanoes like Hawaii was a puzzle. The large circular craters were particularly difficult to interpret.Some thought,even after the Apollo flights,that they were some analogue to terrestrial caldera (e.g.,Green 1971),formed by explosive volcanic activity and that the central peaks were volcanoes.The fact that the craters were mostly circular was difficult to accommodate if they were due to meteorite impact,as meteorites would hit the Moon at all angles.The rilles were taken by many as de finitive evidence that there was or had been,running water on the lunar surface.Others such as Carl Sagan thought that organic compounds were likely present (see Taylor 1975,p.111,note 139).

  3. Religion and Lunar Exploration

    Science.gov (United States)

    Pop, V.

    1969: The Eagle lands on the Moon. A moment that would not only mark the highest scientific achievement of all times, but would also have significant religious impli- cations. While the island of Bali lodges a protest at the United Nations against the US for desecrating a sacred place, Hopi Indians celebrate the fulfilment of an ancient prophecy that would reveal the "truth of the Sacred Ways". The plaque fastened to the Eagle - "We Came in Peace for All Mankind" would have contained the words "under God" as directed by the US president, if not for an assistant administrator at NASA that did not want to offend any religion. In the same time, Buzz Aldrin takes the Holy Communion on the Moon, and a Bible is left there by another Apollo mission - not long after the crew of Apollo 8 reads a passage from Genesis while circling the Moon. 1998: Navajo Indians lodge a protest with NASA for placing human ashes aboard the Lunar Prospector, as the Moon is a sacred place in their religion. Past, present and fu- ture exploration of the Moon has significant religious and spiritual implications that, while not widely known, are nonetheless important. Is lunar exploration a divine duty, or a sacrilege? This article will feature and thoroughly analyse the examples quoted above, as well as other facts, as for instance the plans of establishing lunar cemeteries - welcomed by some religions, and opposed by others.

  4. Minimal theory of massive gravity

    CERN Document Server

    De Felice, Antonio

    2016-01-01

    We propose a new theory of massive gravity with only two propagating degrees of freedom. After defining the theory in the unitary gauge in the vielbein language, we shall perform a Hamiltonian analysis to count the number of physical degrees of freedom, and then study some phenomenologies. While the homogeneous and isotropic background cosmology and the tensor linear perturbations around it are described by exactly the same equations as those in the de Rham - Gabadadze - Tolley (dRGT) massive gravity, the scalar and vector gravitational degrees of freedom are absent in the new theory at the fully nonlinear level. Hence the new theory provides a stable nonlinear completion of the self-accelerating cosmological solution that was originally found in the dRGT theory.

  5. Gravity Scaling of a Power Reactor Water Shield

    Science.gov (United States)

    Reid, Robert S.; Pearson, J. Boise

    2008-01-01

    Water based reactor shielding is being considered as an affordable option for use on initial lunar surface power systems. Heat dissipation in the shield from nuclear sources must be rejected by an auxiliary thermal hydraulic cooling system. The mechanism for transferring heat through the shield is natural convection between the core surface and an array of thermosyphon radiator elements. Natural convection in a 100 kWt lunar surface reactor shield design has been previously evaluated at lower power levels (Pearson, 2007). The current baseline assumes that 5.5 kW are dissipated in the water shield, the preponderance on the core surface, but with some volumetric heating in the naturally circulating water as well. This power is rejected by a radiator located above the shield with a surface temperature of 370 K. A similarity analysis on a water-based reactor shield is presented examining the effect of gravity on free convection between a radiation shield inner vessel and a radiation shield outer vessel boundaries. Two approaches established similarity: 1) direct scaling of Rayleigh number equates gravity-surface heat flux products, 2) temperature difference between the wall and thermal boundary layer held constant on Earth and the Moon. Nussult number for natural convection (laminar and turbulent) is assumed of form Nu = CRa(sup n). These combined results estimate similarity conditions under Earth and Lunar gravities. The influence of reduced gravity on the performance of thermosyphon heat pipes is also examined.

  6. Southern Africa Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data base (14,559 records) was received in January 1986. Principal gravity parameters include elevation and observed gravity. The observed gravity values are...

  7. NGS Absolute Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NGS Absolute Gravity data (78 stations) was received in July 1993. Principal gravity parameters include Gravity Value, Uncertainty, and Vertical Gradient. The...

  8. Flexure and isostasy of lunar mascons

    Science.gov (United States)

    Peters, S. T. M.; Foing, B. H.

    2009-04-01

    A mascon is a region of a planet's or moon's crust that contains an excess positive gravity anomaly, indicating the presence of additional mass in this area. Mascons on the Moon coincide with the locations of circular basins and hence a related origin for both is likely. The formation of a circular basin includes the excavation of the upper parts of the crust and subsequent upwelling of the lower parts as a result of isostatic compensation [1]. Afterwards, filling of the basins by mare basalts leads to concentrations of dense rocks and is hence suggested as the origin of the mascon. The present day presence of mascons indicates that there was no subsequent isostasy leading to downward migration of the moho and that they are hence supported by an elastic layer on the surface of the Moon. The interaction between mascons and this elastic shell is the main topic of our modeling. Since they were discovered by Muller and Sjogren (1968), the origin of mascons and their interaction with the crust became clearer. As we point out below, several questions have however remained unsolved. Our contribution includes the usage of recent gravity and topography models that have not been applied in mascon studies yet. Mascons act like a dense load on the lunar lithosphere and hence flexure it. Flexure profiles of circular basins have been made by previous authors [2], however, only a single-layered crust was considered until now. Our modeling includes the two-layered crustal model preferred by Wieczorek and Phillips (1997) which explains the gravity to topography ratios of the lunar highlands. On the hand of previously existing data it has been suggested that rings of negative gravity anomalies surround the mascons [3]. Whereas this observation was first questionable, prereleases of the high-resolution KAGUYA gravity measurements recently clearly confirmed the presence of these features. Part of our modeling focuses on the location and extent of the negative anomalies in respect to

  9. Lunar radiation environment

    Science.gov (United States)

    Schwadron, Nathan; Spence, Harlan; Wilson, Jody

    One of the goals of the CRaTER investigation is to characterize the radiation environment near the Moon in order to enable exploration. The state-of-the-art understanding developed thus far during the LRO mission is documented in a special issue of the Spaceweather Journal entitled “Space Weather: Building the observational foundation to deduce biological effects of space radiation” (Schwadron et al., 2013a). This recently published CRaTER work probes deeper into the physics of the radiation environment at the Moon. It motivates and provides the scientific basis for new investigations in the next phase of the LRO mission. The effects of Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs) range from chemical modification of the regolith, the generation of a radiation albedo that is increasingly illuminating chemical properties of the regolith, causing charging of the regolith and hazards to human explorers and robotic missions. Low-lunar orbit provides a platform for measuring SEP anisotropy over timescales of 2 hours both parallel and perpendicular to the ecliptic plane, and so far we have observed more than 18 SEP events with time-variable anisotropies during the LRO mission. Albedo proton maps of the Moon from CRaTER indicate that the flux of lunar albedo protons is correlated with elemental abundances at the lunar surface. The yield of albedo protons from the maria is 1% higher than the yield from the highlands, and there are localized peaks with even higher contrast (that may be co-located with peaks in trace elemental abundances as measured by the Lunar Prospector Gamma Ray Spectrometer). The Moon’s radiation environment both charges and affects the chemistry in the Moon’s polar regions, particularly in PSRs. This makes these regions a prime target for new CRaTER observations, since CRaTER measures GCRs and SEPs that penetrate the regolith down to 10s of cm. Thus, we review emerging discoveries from LRO/CRaTER’s remarkable exploration of

  10. Lunar imaging and ionospheric calibration for the Lunar Cherenkov technique

    NARCIS (Netherlands)

    McFadden, R.; Scholten, O.; Mevius, M.

    2013-01-01

    The Lunar Cherenkov technique is a promising method for UHE neutrino and cosmic ray detection which aims to detect nanosecond radio pulses produced during particle interactions in the Lunar regolith. For low frequency experiments, such as NuMoon, the frequency dependent dispersive effect of the iono

  11. Lunar Dust Mitigation Technology Development

    Science.gov (United States)

    Hyatt, Mark J.; Deluane, Paul B.

    2008-01-01

    NASA s plans for implementing the Vision for Space Exploration include returning to the moon as a stepping stone for further exploration of Mars, and beyond. Dust on the lunar surface has a ubiquitous presence which must be explicitly addressed during upcoming human lunar exploration missions. While the operational challenges attributable to dust during the Apollo missions did not prove critical, the comparatively long duration of impending missions presents a different challenge. Near term plans to revisit the moon places a primary emphasis on characterization and mitigation of lunar dust. Comprised of regolith particles ranging in size from tens of nanometers to microns, lunar dust is a manifestation of the complex interaction of the lunar soil with multiple mechanical, electrical, and gravitational effects. The environmental and anthropogenic factors effecting the perturbation, transport, and deposition of lunar dust must be studied in order to mitigate it s potentially harmful effects on exploration systems. This paper presents the current perspective and implementation of dust knowledge management and integration, and mitigation technology development activities within NASA s Exploration Technology Development Program. This work is presented within the context of the Constellation Program s Integrated Lunar Dust Management Strategy. The Lunar Dust Mitigation Technology Development project has been implemented within the ETDP. Project scope and plans will be presented, along with a a perspective on lessons learned from Apollo and forensics engineering studies of Apollo hardware. This paper further outlines the scientific basis for lunar dust behavior, it s characteristics and potential effects, and surveys several potential strategies for its control and mitigation both for lunar surface operations and within the working volumes of a lunar outpost.

  12. [Presentation of the Lunar Precursor Robotics Program

    Science.gov (United States)

    Lavoie, Anthony R.

    2008-01-01

    The Lunar Precursor Robotics Program (LPRP) is the host program for the Exploration Systems Mission Directorate's (ESMD) lunar robotic precursor missions to the Moon. The program includes two missions, the Lunar Reconnaissance Orbiter (LRO), and the Lunar CRater Observation and Sensing Satellite (LCROSS). Both missions will provide the required lunar information to support development and operations of those systems required for Human lunar return. LPRP is developing a lunar mapping plan, Called the Lunar Mapping and Modeling Project, to create the capability to archive and present all data from LRO, LCROSS, historical lunar missions, and international lunar missions for future mission planning and operations. LPRP is also developing its educational and public outreach activities for the Vision for Space Exploration's first missions. LPRP is working closely with the Science Mission Directorate as their lunar activities come into focus.

  13. Topics in quantum gravity

    Energy Technology Data Exchange (ETDEWEB)

    Lamon, Raphael

    2010-06-29

    Quantum gravity is an attempt to unify general relativity with quantum mechanics which are the two highly successful fundamental theories of theoretical physics. The main difficulty in this unification arises from the fact that, while general relativity describes gravity as a macroscopic geometrical theory, quantum mechanics explains microscopic phenomena. As a further complication, not only do both theories describe different scales but also their philosophical ramifications and the mathematics used to describe them differ in a dramatic way. Consequently, one possible starting point of an attempt at a unification is quantum mechanics, i.e. particle physics, and try to incorporate gravitation. This pathway has been chosen by particle physicists which led to string theory. On the other hand, loop quantum gravity (LQG) chooses the other possibility, i.e. it takes the geometrical aspects of gravity seriously and quantizes geometry. The first part of this thesis deals with a generalization of loop quantum cosmology (LQC) to toroidal topologies. LQC is a quantization of homogenous solutions of Einstein's field equations using tools from LQG. First the general concepts of closed topologies is introduced with special emphasis on Thurston's theorem and its consequences. It is shown that new degrees of freedom called Teichmueller parameters come into play and their dynamics can be described by a Hamiltonian. Several numerical solutions for a toroidal universe are presented and discussed. Following the guidelines of LQG this dynamics are rewritten using the Ashtekar variables and numerical solutions are shown. However, in order to find a suitable Hilbert space a canonical transformation must be performed. On the other hand this transformation makes the quantization of geometrical quantities less tractable such that two different ways are presented. It is shown that in both cases the spectrum of such geometrical operators depends on the initial value problem

  14. Gravity's Rainbow

    CERN Document Server

    Magueijo, J; Magueijo, Joao; Smolin, Lee

    2004-01-01

    Non-linear special relativity (or doubly special relativity) is a simple framework for encoding properties of flat quantum space-time. In this paper we show how this formalism may be generalized to incorporate curvature (leading to what might be called ``doubly general relativity''). We first propose a dual to non-linear realizations of relativity in momentum space, and show that for such a dual the space-time invariant is an energy-dependent metric. This leads to an energy-dependent connection and curvature, and a simple modification to Einstein's equations. We then examine solutions to these equations. We find the counterpart to the cosmological metric, and show how cosmologies based upon our theory of gravity may solve the ``horizon problem''. We discuss the Schwarzchild solution, examining the conditions for which the horizon is energy dependent. We finally find the weak field limit.

  15. Network Gravity

    CERN Document Server

    Lombard, John

    2016-01-01

    We introduce the construction of a new framework for probing discrete emergent geometry and boundary-boundary observables based on a fundamentally a-dimensional underlying network structure. Using a gravitationally motivated action with Forman weighted combinatorial curvatures and simplicial volumes relying on a decomposition of an abstract simplicial complex into realized embeddings of proper skeletons, we demonstrate properties such as a minimal volume-scale cutoff, the necessity of a positive-definite cosmological constant as a regulator for non-degenerate geometries, and naturally emergent simplicial structures from Metropolis network evolution simulations with no restrictions on attachment rules or regular building blocks. We see emergent properties which echo results from both the spinfoam formalism and causal dynamical triangulations in quantum gravity, and provide analytical and numerical results to support the analogy. We conclude with a summary of open questions and intent for future work in develop...

  16. An analysis of near-circular lunar mapping orbits

    Indian Academy of Sciences (India)

    R V Ramanan; V Adimurthy

    2005-12-01

    Numerical investigations have been carried out to analyse the evolution of lunar circular orbits and the influence of the higher order harmonics of the lunar gravity field.The aim is to select the appropriate near-circular orbit characteristics,which extend orbit life through passive orbit maintenance.The spherical harmonic terms that make major contributions to the orbital behaviour are identified through many case studies.It is found that for low circular orbits,the 7th and the 9th zonal harmonics have predominant effect in the case of orbits for which the evolution is stable and the life is longer,and also in the case of orbits for which the evolution is unstable and a crash takes place in a short duration.By analysing the contribution of the harmonic terms to the orbit behaviour,the appropriate near-circular orbit characteristics are identified.

  17. Energy conditions in modified gravity

    Energy Technology Data Exchange (ETDEWEB)

    Capozziello, Salvatore, E-mail: capozzie@na.infn.it [Dipartimento di Fisica, Università di Napoli “Federico II”, Napoli (Italy); INFN Sez. di Napoli, Compl. Univ. di Monte S. Angelo, Edificio G, Via Cinthia, I-80126, Napoli (Italy); Lobo, Francisco S.N., E-mail: flobo@cii.fc.ul.pt [Centro de Astronomia e Astrofísica da Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016 Lisboa (Portugal); Mimoso, José P., E-mail: jpmimoso@cii.fc.ul.pt [Centro de Astronomia e Astrofísica da Universidade de Lisboa, Campo Grande, Edifício C8, 1749-016 Lisboa (Portugal); Departamento de Física, Faculdade de Ciências da Universidade de Lisboa, Faculdade de Ciências da Universidade de Lisboa, Edifício C8, Campo Grande, P-1749-016 Lisbon (Portugal)

    2014-03-07

    We consider generalized energy conditions in modified theories of gravity by taking into account the further degrees of freedom related to scalar fields and curvature invariants. The latter are usually recast as generalized geometrical fluids that have different meanings with respect to the standard matter fluids generally adopted as sources of the field equations. More specifically, in modified gravity the curvature terms are grouped in a tensor H{sup ab} and a coupling g(Ψ{sup i}) that can be reorganized in effective Einstein field equations, as corrections to the energy–momentum tensor of matter. The formal validity of such inequalities does not assure some basic requirements such as the attractive nature of gravity, so that the energy conditions have to be considered in a wider sense.

  18. Energy conditions in modified gravity

    CERN Document Server

    Capozziello, Salvatore; Mimoso, José P

    2014-01-01

    We consider generalized energy conditions in modified theories of gravity by taking into account the further degrees of freedom related to scalar fields and curvature invariants. The latter are usually recast as generalized {\\it geometrical fluids} that have different meanings with respect to the standard matter fluids generally adopted as sources of the field equations. More specifically, in modified gravity the curvature terms are grouped in a tensor $H^{ab}$ and a coupling $g(\\Psi^i)$ that can be reorganized in effective Einstein field equations, as corrections to the energy-momentum tensor of matter. The formal validity of such inequalities does not assure some basic requirements such as the attractive nature of gravity, so that the energy conditions have to be considered in a wider sense.

  19. Gravity On-shell Diagrams

    CERN Document Server

    Herrmann, Enrico

    2016-01-01

    We study on-shell diagrams for gravity theories with any number of supersymmetries and find a compact Grassmannian formula in terms of edge variables of the graphs. Unlike in gauge theory where the analogous form involves only $\\dlog$-factors, in gravity there is a non-trivial numerator as well as higher degree poles in the edge variables. Based on the structure of the Grassmannian formula for $\\N=8$ supergravity we conjecture that gravity loop amplitudes also possess similar properties. In particular, we find that there are only logarithmic singularities on cuts with finite loop momentum, poles at infinity are present and loop amplitudes show special behavior on certain collinear cuts. We demonstrate on 1-loop and 2-loop examples that the behavior on collinear cuts is a highly non-trivial property which requires cancellations between all terms contributing to the amplitude.

  20. Gravity on-shell diagrams

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, Enrico [Walter Burke Institute for Theoretical Physics, California Institute of Technology,Pasadena, CA 91125 (United States); Trnka, Jaroslav [Center for Quantum Mathematics and Physics (QMAP),Department of Physics, University of California,Davis, CA 95616 (United States)

    2016-11-22

    We study on-shell diagrams for gravity theories with any number of supersymmetries and find a compact Grassmannian formula in terms of edge variables of the graphs. Unlike in gauge theory where the analogous form involves only dlog-factors, in gravity there is a non-trivial numerator as well as higher degree poles in the edge variables. Based on the structure of the Grassmannian formula for N=8 supergravity we conjecture that gravity loop amplitudes also possess similar properties. In particular, we find that there are only logarithmic singularities on cuts with finite loop momentum and that poles at infinity are present, in complete agreement with the conjecture presented in http://dx.doi.org/10.1007/JHEP06(2015)202.

  1. Newtonian gravity in loop quantum gravity

    OpenAIRE

    Smolin, Lee

    2010-01-01

    We apply a recent argument of Verlinde to loop quantum gravity, to conclude that Newton's law of gravity emerges in an appropriate limit and setting. This is possible because the relationship between area and entropy is realized in loop quantum gravity when boundaries are imposed on a quantum spacetime.

  2. Newtonian gravity in loop quantum gravity

    OpenAIRE

    Smolin, Lee

    2010-01-01

    We apply a recent argument of Verlinde to loop quantum gravity, to conclude that Newton's law of gravity emerges in an appropriate limit and setting. This is possible because the relationship between area and entropy is realized in loop quantum gravity when boundaries are imposed on a quantum spacetime.

  3. Optimal lunar soft landing trajectories using taboo evolutionary programming

    Science.gov (United States)

    Mutyalarao, M.; Raj, M. Xavier James

    A safe lunar landing is a key factor to undertake an effective lunar exploration. Lunar lander consists of four phases such as launch phase, the earth-moon transfer phase, circumlunar phase and landing phase. The landing phase can be either hard landing or soft landing. Hard landing means the vehicle lands under the influence of gravity without any deceleration measures. However, soft landing reduces the vertical velocity of the vehicle before landing. Therefore, for the safety of the astronauts as well as the vehicle lunar soft landing with an acceptable velocity is very much essential. So it is important to design the optimal lunar soft landing trajectory with minimum fuel consumption. Optimization of Lunar Soft landing is a complex optimal control problem. In this paper, an analysis related to lunar soft landing from a parking orbit around Moon has been carried out. A two-dimensional trajectory optimization problem is attempted. The problem is complex due to the presence of system constraints. To solve the time-history of control parameters, the problem is converted into two point boundary value problem by using the maximum principle of Pontrygen. Taboo Evolutionary Programming (TEP) technique is a stochastic method developed in recent years and successfully implemented in several fields of research. It combines the features of taboo search and single-point mutation evolutionary programming. Identifying the best unknown parameters of the problem under consideration is the central idea for many space trajectory optimization problems. The TEP technique is used in the present methodology for the best estimation of initial unknown parameters by minimizing objective function interms of fuel requirements. The optimal estimation subsequently results into an optimal trajectory design of a module for soft landing on the Moon from a lunar parking orbit. Numerical simulations demonstrate that the proposed approach is highly efficient and it reduces the minimum fuel

  4. Apollo 15-Lunar Module Falcon

    Science.gov (United States)

    1971-01-01

    This is a photo of the Apollo 15 Lunar Module, Falcon, on the lunar surface. Apollo 15 launched from Kennedy Space Center (KSC) on July 26, 1971 via a Saturn V launch vehicle. Aboard was a crew of three astronauts including David R. Scott, Mission Commander; James B. Irwin, Lunar Module Pilot; and Alfred M. Worden, Command Module Pilot. The first mission designed to explore the Moon over longer periods, greater ranges and with more instruments for the collection of scientific data than on previous missions, the mission included the introduction of a $40,000,000 lunar roving vehicle (LRV) that reached a top speed of 16 kph (10 mph) across the Moon's surface. The successful Apollo 15 lunar landing mission was the first in a series of three advanced missions planned for the Apollo program. The primary scientific objectives were to observe the lunar surface, survey and sample material and surface features in a preselected area of the Hadley-Apennine region, setup and activation of surface experiments and conduct in-flight experiments and photographic tasks from lunar orbit. Apollo 15 televised the first lunar liftoff and recorded a walk in deep space by Alfred Worden. Both the Saturn V rocket and the LRV were developed at the Marshall Space Flight Center.

  5. Subduction zones seen by GOCE gravity gradients

    DEFF Research Database (Denmark)

    Švarc, Mario; Herceg, Matija; Cammarano, Fabio

    In this study, the GOCE (Gravity field and steady state Ocean Circulation Explorer) gradiometry data were used to study geologic structures and mass variations within the lithosphere in areas of known subduction zones. The advantage of gravity gradiometry over other gravity methods is that gradie......In this study, the GOCE (Gravity field and steady state Ocean Circulation Explorer) gradiometry data were used to study geologic structures and mass variations within the lithosphere in areas of known subduction zones. The advantage of gravity gradiometry over other gravity methods...... is that gradients are extremely sensitive to localized density contrasts within regional geological settings, which makes it ideally suited for detecting subduction zones. Second order gravity gradients of disturbing potential were extracted from global geopotential model, the fifth release GOCE model ‘EGM_TIM_RL05......’. In order to remove the signal which mainly corresponds to the gravity signal of the lower mantle, long wavelength part of the gravity signal was removed up to degree and order 60. Because the areas with notable topography differences coincide with subduction zones, topography correction was also performed...

  6. Electrostatic Characterization of Lunar Dust

    Science.gov (United States)

    2008-01-01

    To ensure the safety and success of future lunar exploration missions, it is important to measure the toxicity of the lunar dust and its electrostatic properties. The electrostatic properties of lunar dust govern its behavior, from how the dust is deposited in an astronaut s lungs to how it contaminates equipment surfaces. NASA has identified the threat caused by lunar dust as one of the top two problems that need to be solved before returning to the Moon. To understand the electrostatic nature of lunar dust, NASA must answer the following questions: (1) how much charge can accumulate on the dust? (2) how long will the charge remain? and (3) can the dust be removed? These questions can be answered by measuring the electrostatic properties of the dust: its volume resistivity, charge decay, charge-to-mass ratio or chargeability, and dielectric properties.

  7. Lunar Regolith Particle Shape Analysis

    Science.gov (United States)

    Kiekhaefer, Rebecca; Hardy, Sandra; Rickman, Douglas; Edmunson, Jennifer

    2013-01-01

    Future engineering of structures and equipment on the lunar surface requires significant understanding of particle characteristics of the lunar regolith. Nearly all sediment characteristics are influenced by particle shape; therefore a method of quantifying particle shape is useful both in lunar and terrestrial applications. We have created a method to quantify particle shape, specifically for lunar regolith, using image processing. Photomicrographs of thin sections of lunar core material were obtained under reflected light. Three photomicrographs were analyzed using ImageJ and MATLAB. From the image analysis measurements for area, perimeter, Feret diameter, orthogonal Feret diameter, Heywood factor, aspect ratio, sieve diameter, and sieve number were recorded. Probability distribution functions were created from the measurements of Heywood factor and aspect ratio.

  8. Teaching Physics from a Reduced Gravity Environment

    Science.gov (United States)

    Benge, Raymond D.; Young, C.; Davis, S.; Worley, A.; Smith, L.; Gell, A.

    2010-01-01

    This poster reports on an educational experiment flown in January 2009 as part of NASA's Microgravity University program. The experiment flown was an investigation into the properties of harmonic oscillators in reduced gravity. Harmonic oscillators are studied in every introductory physics class. The equation for the period of a harmonic oscillator does not include the acceleration due to gravity, so the period should be independent of gravity. However, the equation for the period of a pendulum does include the acceleration due to gravity, so the period of a pendulum should appear longer under reduced gravity (such as lunar or Martian gravity) and shorter under hyper-gravity. Typical homework problems for introductory physics classes ask questions such as "What would be the period of oscillation if this experiment were performed on the Moon or Mars?” This gives students a chance to actually see the effects predicted by the equations. These environments can be simulated aboard an aircraft. Video of the experiments being performed aboard the aircraft is to be used in introductory physics classes. Students will be able to record information from watching the experiment performed aboard the aircraft in a similar manner to how they collect data in the laboratory. They can then determine if the experiment matches theory. Video and an experimental procedure are being prepared based upon this flight, and these materials will be available for download by faculty anywhere with access to the internet who wish to use the experiment in their own classrooms in both college and high school physics classes.

  9. The lunar thermal ice pump

    Energy Technology Data Exchange (ETDEWEB)

    Schorghofer, Norbert [Institute for Astronomy and NASA Astrobiology Institute, University of Hawaii, Honolulu, HI 96822 (United States); Aharonson, Oded, E-mail: norbert@hawaii.edu [Helen Kimmel Center for Planetary Science, Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 76100 (Israel)

    2014-06-20

    It has long been suggested that water ice can exist in extremely cold regions near the lunar poles, where sublimation loss is negligible. The geographic distribution of H-bearing regolith shows only a partial or ambiguous correlation with permanently shadowed areas, thus suggesting that another mechanism may contribute to locally enhancing water concentrations. We show that under suitable conditions, water molecules can be pumped down into the regolith by day-night temperature cycles, leading to an enrichment of H{sub 2}O in excess of the surface concentration. Ideal conditions for pumping are estimated and found to occur where the mean surface temperature is below 105 K and the peak surface temperature is above 120 K. These conditions complement those of the classical cold traps that are roughly defined by peak temperatures lower than 120 K. On the present-day Moon, an estimated 0.8% of the global surface area experiences such temperature variations. Typically, pumping occurs on pole-facing slopes in small areas, but within a few degrees of each pole the equator-facing slopes are preferred. Although pumping of water molecules is expected over cumulatively large areas, the absolute yield of this pump is low; at best, a few percent of the H{sub 2}O delivered to the surface could have accumulated in the near-surface layer in this way. The amount of ice increases with vapor diffusivity and is thus higher in the regolith with large pore spaces.

  10. Lunar Commercial Mining Logistics

    Science.gov (United States)

    Kistler, Walter P.; Citron, Bob; Taylor, Thomas C.

    2008-01-01

    Innovative commercial logistics is required for supporting lunar resource recovery operations and assisting larger consortiums in lunar mining, base operations, camp consumables and the future commercial sales of propellant over the next 50 years. To assist in lowering overall development costs, ``reuse'' innovation is suggested in reusing modified LTS in-space hardware for use on the moon's surface, developing product lines for recovered gases, regolith construction materials, surface logistics services, and other services as they evolve, (Kistler, Citron and Taylor, 2005) Surface logistics architecture is designed to have sustainable growth over 50 years, financed by private sector partners and capable of cargo transportation in both directions in support of lunar development and resource recovery development. The author's perspective on the importance of logistics is based on five years experience at remote sites on Earth, where remote base supply chain logistics didn't always work, (Taylor, 1975a). The planning and control of the flow of goods and materials to and from the moon's surface may be the most complicated logistics challenges yet to be attempted. Affordability is tied to the innovation and ingenuity used to keep the transportation and surface operations costs as low as practical. Eleven innovations are proposed and discussed by an entrepreneurial commercial space startup team that has had success in introducing commercial space innovation and reducing the cost of space operations in the past. This logistics architecture offers NASA and other exploring nations a commercial alternative for non-essential cargo. Five transportation technologies and eleven surface innovations create the logistics transportation system discussed.

  11. Non-local massive gravity

    CERN Document Server

    Modesto, Leonardo

    2013-01-01

    We present a general covariant action for massive gravity merging together a class of "non-polynomial" and super-renormalizable or finite theories of gravity with the non-local theory of gravity recently proposed by Jaccard, Maggiore and Mitsou (arXiv:1305.3034 [hep-th]). Our diffeomorphism invariant action gives rise to the equations of motion appearing in non-local massive massive gravity plus quadratic curvature terms. Not only the massive graviton propagator reduces smoothly to the massless one without a vDVZ discontinuity, but also our finite theory of gravity is unitary at tree level around the Minkowski background. We also show that, as long as the graviton mass $m$ is much smaller the today's Hubble parameter $H_0$, a late-time cosmic acceleration can be realized without a dark energy component due to the growth of a scalar degree of freedom. In the presence of the cosmological constant $\\Lambda$, the dominance of the non-local mass term leads to a kind of "degravitation" for $\\Lambda$ at the late cos...

  12. A locally finite model for gravity

    NARCIS (Netherlands)

    't Hooft, G.

    2008-01-01

    Matter interacting classically with gravity in 3+1 dimensions usually gives rise to a continuum of degrees of freedom, so that, in any attempt to quantize the theory, ultraviolet divergences are nearly inevitable. Here, we investigate matter of a form that only displays a finite number of degrees of

  13. Lineal gravity from planar gravity

    CERN Document Server

    Achúcarro, A

    1993-01-01

    We show how to obtain the two-dimensional black hole action by dimensional reduction of the three-dimensional Einstein action with a non-zero cosmological constant. Starting from the Chern-Simons formulation of 2+1 gravity, we obtain the 1+1 dimensional gauge formulation given by Verlinde. Remarkably, the proposed reduction shares the relevant features of the formulation of Cangemi and Jackiw, without the need for a central charge in the algebra. We show how the Lagrange multipliersin these formulations appear naturally as the remnants of the three dimensional connection associated to symmetries that have been lostin the dimensional reduction. The proposed dimensional reduction involves a shift in the three dimensional connection whose effect is to make the length of the extra dimension infinite.

  14. Lunar Influences On Climate

    Science.gov (United States)

    Camuffo, Dario

    Popular beliefs on the effects of the Moon on the weather probably go back to when ancient civilisations followed a lunar calendar, and the Moon went from being a purely temporal reference to becoming a causal reference. The incoming heat flow on the Earth may vary slightly after solar activity. to and generate considerable effects. The light reflected from the Moon has also been hypothesised as a cause, but the associated energy is too small. The anomalistic period of the Moon (i.e., 27.5 days) coincides substantially with that of the sunspots found on the 17-18th parallel of the heliocentric latitude. Climatic modulation which lasts for around 27.5 days should be related to solar activity, which supplies energy with an amount of two orders of magnitude greater than the lunar-reflected energy. Another mechanism responsible for climatic variations is the redistribution of heat on the Earth. The Moon with the tides induces movement of the water masses of the oceans and with this there is a transport of heat. Semidiurnal lunar tides have been identified, although with modest impact, in the atmospheric pressure, the wind field and the precipitation. On a monthly time scale, variation of daily precipitation data shows that gravitational tides do indeed affect heavy rainfalls more than mean precipitation values. On the longer time scale, several authors have identified the 18.6-yr nutation cycle, which is clearly visible in several data analyses, but often it cannot be easily distinguished from the 19.9 Saturn-Jupiter cycle and the quasi-regular 22-yr double sunspot cycle which at times may be dominant. In the time scale of centuries, covering a number of periods with minimum solar activity, an analysis of meteorological data has demonstrated that only the Spörer Minimum (A.D. 1416-1534) was characterised by climatic anomalies., whereas the other periods had no singularities, or else the weak climate forcing was covered or masked by other factors, leaving the question

  15. NASA Lunar Impact Monitoring

    Science.gov (United States)

    Suggs, Robert M.; Moser, D. E.

    2015-01-01

    The MSFC lunar impact monitoring program began in 2006 in support of environment definition for the Constellation (return to Moon) program. Work continued by the Meteoroid Environment Office after Constellation cancellation. Over 330 impacts have been recorded. A paper published in Icarus reported on the first 5 years of observations and 126 calibrated flashes. Icarus: http://www.sciencedirect.com/science/article/pii/S0019103514002243; ArXiv: http://arxiv.org/abs/1404.6458 A NASA Technical Memorandum on flash locations is in press

  16. Lunar architecture and urbanism

    Science.gov (United States)

    Sherwood, Brent

    1992-01-01

    Human civilization and architecture have defined each other for over 5000 years on Earth. Even in the novel environment of space, persistent issues of human urbanism will eclipse, within a historically short time, the technical challenges of space settlement that dominate our current view. By adding modern topics in space engineering, planetology, life support, human factors, material invention, and conservation to their already renaissance array of expertise, urban designers can responsibly apply ancient, proven standards to the exciting new opportunities afforded by space. Inescapable facts about the Moon set real boundaries within which tenable lunar urbanism and its component architecture must eventually develop.

  17. Precambrian Lunar Volcanic Protolife

    Directory of Open Access Journals (Sweden)

    Jack Green

    2009-06-01

    Full Text Available Five representative terrestrial analogs of lunar craters are detailed relevant to Precambrian fumarolic activity. Fumarolic fluids contain the ingredients for protolife. Energy sources to derive formaldehyde, amino acids and related compounds could be by flow charging, charge separation and volcanic shock. With no photodecomposition in shadow, most fumarolic fluids at 40 K would persist over geologically long time periods. Relatively abundant tungsten would permit creation of critical enzymes, Fischer-Tropsch reactions could form polycyclic aromatic hydrocarbons and soluble volcanic polyphosphates would enable assembly of nucleic acids. Fumarolic stimuli factors are described. Orbital and lander sensors specific to protolife exploration including combined Raman/laser-induced breakdown spectrocsopy are evaluated.

  18. Lunar Module Illustration

    Science.gov (United States)

    1969-01-01

    This concept is a cutaway illustration of the Lunar Module (LM) with detailed callouts. The LM was a two part spacecraft. Its lower or descent stage had the landing gear, engines, and fuel needed for the landing. When the LM blasted off the Moon, the descent stage served as the launching pad for its companion ascent stage, which was also home for the two astronauts on the surface of the Moon. The LM was full of gear with which to communicate, navigate, and rendezvous. It also had its own propulsion system, and an engine to lift it off the Moon and send it on a course toward the orbiting Command Module.

  19. Examining spectral variations in localized lunar dark mantle deposits

    Science.gov (United States)

    Jawin, Erica; Besse, Sebastien; Gaddis, Lisa R.; Sunshine, Jessica; Head, James W.; Mazrouei, Sara

    2015-01-01

    The localized lunar dark mantle deposits (DMDs) in Alphonsus, J. Herschel, and Oppenheimer craters were analyzed using visible-near-infrared spectroscopy data from the Moon Mineralogy Mapper. Spectra of these localized DMDs were analyzed for compositional and mineralogical variations within the deposits and were compared with nearby mare basalt units. Spectra of the three localized DMDs exhibited mafic absorption features indicating iron-rich compositions, although the DMDs were spectrally distinct from nearby mare basalts. All of the DMDs contained spectral signatures of glassy materials, suggesting the presence of volcanic glass in varying concentrations across the individual deposits. In addition, the albedo and spectral signatures were variable within the Alphonsus and Oppenheimer crater DMDs, suggesting variable deposit thickness and/or variations in the amount of mixing with the local substrate. Two previously unidentified localized DMDs were discovered to the northeast of Oppenheimer crater. The identification of high concentrations of volcanic glass in multiple localized DMDs in different locations suggests that the distribution of volcanic glass across the lunar surface is much more widespread than has been previously documented. The presence of volcanic glass implies an explosive, vulcanian eruption style for localized DMDs, as this allows volcanic glass to rapidly quench, inhibiting crystallization, compared to the larger hawaiian-style eruptions typical of regional DMD emplacement where black beads indicate a higher degree of crystallization. Improved understanding of the local and global distributions of volcanic glass in lunar DMDs will further constrain lunar degassing and compositional evolution throughout lunar volcanic history.

  20. Fast Ray Tracing of Lunar Digital Elevation Models

    Science.gov (United States)

    McClanahan, Timothy P.; Evans, L. G.; Starr, R. D.; Mitrofanov, I.

    2009-01-01

    Ray-tracing (RT) of Lunar Digital Elevation Models (DEM)'s is performed to virtually derive the degree of radiation incident to terrain as a function of time, orbital and ephemeris constraints [I- 4]. This process is an integral modeling process in lunar polar research and exploration due to the present paucity of terrain information at the poles and mission planning activities for the anticipated spring 2009 launch of the Lunar Reconnaissance Orbiter (LRO). As part of the Lunar Exploration Neutron Detector (LEND) and Lunar Crater Observation and Sensing Satellite (LCROSS) preparations RI methods are used to estimate the critical conditions presented by the combined effects of high latitude, terrain and the moons low obliquity [5-7]. These factors yield low incident solar illumination and subsequently extreme thermal, and radiation conditions. The presented research uses RT methods both for radiation transport modeling in space and regolith related research as well as to derive permanently shadowed regions (PSR)'s in high latitude topographic minima, e.g craters. These regions are of scientific and human exploration interest due to the near constant low temperatures in PSRs, inferred to be < 100 K. Hydrogen is thought to have accumulated in PSR's through the combined effects of periodic cometary bombardment and/or solar wind processes, and the extreme cold which minimizes hydrogen sublimation [8-9]. RT methods are also of use in surface position optimization for future illumination dependent on surface resources e.g. power and communications equipment.

  1. Understanding the Reactivity of Lunar Dust for Future Lunar Missions

    Science.gov (United States)

    Wallace, William; Taylor, L. A.; Jeevarajan, Antony

    2009-01-01

    During the Apollo missions, dust was found to cause numerous problems for various instruments and systems. Additionally, the dust may have caused momentary health issues for some of the astronauts. Therefore, the plan to resume robotic and manned missions to the Moon in the next decade has led to a renewed interest in the properties of lunar dust, ranging from geological to chemical to toxicological. An important property to understand is the reactivity of the dust particles. Due to the lack of an atmosphere on the Moon, there is nothing to protect the lunar soil from ultraviolet radiation, solar wind, and meteorite impacts. These processes could all serve to activate the soil, or produce reactive surface species. On the Moon, these species can be maintained for millennia without oxygen or water vapor present to satisfy the broken bonds. Unfortunately, the Apollo dust samples that were returned to Earth were inadvertently exposed to the atmosphere, causing them to lose their reactive characteristics. In order to aid in the preparation of mitigation techniques prior to returning to the Moon, we measured the ability of lunar dust, lunar dust simulant, and quartz samples to produce hydroxyl radicals in solution[1]. As a first approximation of meteorite impacts on the lunar surface, we ground samples using a mortar and pestle. Our initial studies showed that all three test materials (lunar dust (62241), lunar dust simulant (JSC-1Avf), and quartz) produced hydroxyl radicals after grinding and mixing with water. However, the radical production of the ground lunar dust was approximately 10-fold and 3-fold greater than quartz and JSC-1 Avf, respectively. These reactivity differences between the different samples did not correlate with differences in specific surface area. The increased reactivity produced for the quartz by grinding was attributed to the presence of silicon- or oxygen-based radicals on the surface, as had been seen previously[2]. These radicals may also

  2. Time delays across saddles as a test of modified gravity

    CERN Document Server

    Magueijo, Joao

    2012-01-01

    Modified gravity theories can produce strong signals in the vicinity of the saddles of the total gravitational potential. In a sub-class of these models this translates into diverging time-delays for echoes crossing the saddles. Such models arise from the possibility that gravity might be infrared divergent or confined, and if suitably designed they are very difficult to rule out. We show that Lunar Laser Ranging during an eclipse could probe the time-delay effect within meters of the saddle, thereby proving or excluding these models. Very Large Baseline Interferometry, instead, could target delays across the Jupiter-Sun saddle. Such experiments would shed light on the infrared behaviour of gravity and examine the puzzling possibility that there might be well-hidden regions of strong gravity and even singularities inside the solar system.

  3. Towards a Moon Village: Young Lunar Explorers Report

    Science.gov (United States)

    Kamps, Oscar; Foing, Bernard; Batenburg, Peter

    2016-04-01

    Introduction: The Moon Village Workshop at ESTEC on the 14th December 2015 was organized by ILEWG/ESTEC in conjunction with the Moon 2020-2030 Symposium. It gathered a multi-disciplinary group of professionals from all around the world to discuss their ideas about the concept of a Moon Village, the vision of ESA's Director General (DG) Jan Woerner of a permanent lunar base within the next decades [1]. The workshop participants split in three working groups focusing on Moon Habitat Design, science and technology potentials of the Moon Village, and engaging stakeholders [2-3]. Their results and recommendations are presented in this abstract. The Moon Habitat Design group identified that the lunar base design is strongly driven by the lunar environment, which is characterized by high radiation, meteoroids, abrasive dust particles, low gravity and vacu-um. The base location is recommended to be near the poles to provide optimized illumination conditions for power generation, permanent communication to Earth, moderate temperature gradients at the surface and interesting subjects to scientific investigations. The abundance of nearby available resources, especially ice at the dark bottoms of craters, can be exploited in terms of In-Situ Resources Utilization (ISRU). The identified infrastructural requirements include a navigation, data- & commlink network, storage facilities and sustainable use of resources. This involves a high degree of recycling, closed-loop life support and use of 3D-printing technology, which are all technologies with great potential for terrestrial spin-off applications. For the site planning of the Moon Village, proven ideas from urban planning on Earth should be taken into account. A couple of principles, which could improve the quality of a long-term living milieu on the Moon, are creating spacious environments, visibility between interior and exterior spaces, areas with flora, such as gardens and greenhouses, establishing a sustainable community

  4. Accuracy Analysis for SST Gravity Field Model in China

    Institute of Scientific and Technical Information of China (English)

    LUO Jia; LUO Zhicai; ZOU Xiancai; WANG Haihong

    2006-01-01

    Taking China as the region for test, the potential of the new satellite gravity technique, satellite-to-satellite tracking for improving the accuracy of regional gravity field model is studied. With WDM94 as reference, the gravity anomaly residuals of three models, the latest two GRACE global gravity field model (EIGEN_GRACE02S, GGM02S) and EGM96, are computed and compared. The causes for the differences among the residuals of the three models are discussed. The comparison between the residuals shows that in the selected region, EIGEN_GRACE02S or GGM02S is better than EGM96 in lower degree part (less than 110 degree). Additionally, through the analysis of the model gravity anomaly residuals, it is found that some systematic errors with periodical properties exist in the higher degree part of EIGEN and GGM models, the results can also be taken as references in the validation of the SST gravity data.

  5. Three-dimensional density structure of the lunar upper lithosphere

    Science.gov (United States)

    Liang, Q.; Du, J.; Chen, C.; Li, Y.

    2011-12-01

    The lithosphere of the Moon has a thickness over 1200 km according to the seismology studies. It records the giant impact events during the processes of solidification. The upper lithosphere including the crust and the upper mantle was thought to be a nonuniform layer in thickness and seismic velocity, yet the lateral density structure remains poorly understood. The global gravity data thus provides a significant constraint on the three-dimensional (3-D) density structure of the Moon. Previous studies assumed that the crust and the mantle have constant density the gravity anomalies are only produced by the variations of interface between the crust and the mantle. Therefore, the constant density may give overestimation or underestimation of the Moho depth. In contrast, we apply a 3-D inverse method in spherical coordinate to the lunar gravity anomaly. It is a direct way in recovering the density structures beneath mascon basins or the lateral density heterogeneities in the upper lithosphere. The gravity anomaly we use in this study is the Bouguer gravity anomaly calculated at 1750 km radius relative to the reference radius, 1737.153 km[1], from the newly gravity field model SGM100i[2] and the topography model LRO_LTM02[1]. In order to understand the global feature of density variation, we truncate the long wavelength anomaly up to the order of 30 to reconstruct the density distribution above the depth of 100 km in the Moon. With the inverse technique, we obtain a global 3-D density structure of the lunar lithosphere down to 100 km depth. The major features are dominated by the mascons with dense materials and the broad region of the farside highland with relative low density mass. From this structure, the huge mass concentrations are found beneath the South Pole-Aitken (SPA) basin, meaning that the oblique impact not only excavated the SPA basin into deep but also made the mantle uplifted close to a depth of 30 km (relative to a 1738 km radius). We suggest here that

  6. On-board image compression for the RAE lunar mission

    Science.gov (United States)

    Miller, W. H.; Lynch, T. J.

    1976-01-01

    The requirements, design, implementation, and flight performance of an on-board image compression system for the lunar orbiting Radio Astronomy Explorer-2 (RAE-2) spacecraft are described. The image to be compressed is a panoramic camera view of the long radio astronomy antenna booms used for gravity-gradient stabilization of the spacecraft. A compression ratio of 32 to 1 is obtained by a combination of scan line skipping and adaptive run-length coding. The compressed imagery data are convolutionally encoded for error protection. This image compression system occupies about 1000 cu cm and consumes 0.4 W.

  7. APOLLO: the Apache Point Observatory Lunar Laser-ranging Operation: Instrument Description and First Detections

    CERN Document Server

    Murphy, T W Jr; Battat, J B R; Carey, L N; Hoyle, C D; LeBlanc, P; Michelsen, E L; Nordtvedt, K; Orin, A E; Strasburg, J D; Stubbs, C W; Swanson, H E; Williams, E

    2007-01-01

    A next-generation lunar laser ranging apparatus using the 3.5 m telescope at the Apache Point Observatory in southern New Mexico has begun science operation. APOLLO (the Apache Point Observatory Lunar Laser-ranging Operation) has achieved one-millimeter range precision to the moon which should lead to approximately one-order-of-magnitude improvements in the precision of several tests of fundamental properties of gravity. We briefly motivate the scientific goals, and then give a detailed discussion of the APOLLO instrumentation.

  8. Perturbations in Massive Gravity Cosmology

    CERN Document Server

    Crisostomi, Marco; Pilo, Luigi

    2012-01-01

    We study cosmological perturbations for a ghost free massive gravity theory formulated with a dynamical extra metric that is needed to massive deform GR. In this formulation FRW background solutions fall in two branches. In the dynamics of perturbations around the first branch solutions, no extra degree of freedom with respect to GR ispresent at linearized level, likewise what is found in the Stuckelberg formulation of massive gravity where the extra metric isflat and non dynamical. In the first branch, perturbations are probably strongly coupled. On the contrary, for perturbations around the second branch solutions all expected degrees of freedom propagate. While tensor and vector perturbations of the physical metric that couples with matter follow closely the ones of GR, scalars develop an exponential Jeans-like instability on sub-horizon scales. On the other hand, around a de Sitter background there is no instability. We argue that one could get rid of the instabilities by introducing a mirror dark matter ...

  9. Lectures on Gravity and Entanglement

    CERN Document Server

    Van Raamsdonk, Mark

    2016-01-01

    The AdS/CFT correspondence provides quantum theories of gravity in which spacetime and gravitational physics emerge from ordinary non-gravitational quantum systems with many degrees of freedom. Recent work in this context has uncovered fascinating connections between quantum information theory and quantum gravity, suggesting that spacetime geometry is directly related to the entanglement structure of the underlying quantum mechanical degrees of freedom and that aspects of spacetime dynamics (gravitation) can be understood from basic quantum information theoretic constraints. In these notes, we provide an elementary introduction to these developments, suitable for readers with some background in general relativity and quantum field theory. The notes are based on lectures given at the CERN Spring School 2014, the Jerusalem Winter School 2014, the TASI Summer School 2015, and the Trieste Spring School 2015.

  10. Establishing lunar resource viability

    Science.gov (United States)

    Carpenter, J.; Fisackerly, R.; Houdou, B.

    2016-11-01

    Recent research has highlighted the potential of lunar resources as an important element of space exploration but their viability has not been demonstrated. Establishing whether or not they can be considered in future plans is a multidisciplinary effort, requiring scientific expertise and delivering scientific results. To this end various space agencies and private entities are looking to lunar resources, extracted and processed in situ, as a potentially game changing element in future space architectures, with the potential to increase scale and reduce cost. However, before any decisions can be made on the inclusion of resources in exploration roadmaps or future scenarios some big questions need to be answered about the viability of different resource deposits and the processes for extraction and utilisation. The missions and measurements that will be required to answer these questions, and which are being prepared by agencies and others, can only be performed through the engagement and support of the science community. In answering questions about resources, data and knowledge will be generated that is of fundamental scientific importance. In supporting resource prospecting missions the science community will de facto generate new scientific knowledge. Science enables exploration and exploration enables science.

  11. Lunar Base Sitting

    Science.gov (United States)

    Staehle, Robert L.; Burke, James D.; Snyder, Gerald C.; Dowling, Richard; Spudis, Paul D.

    1993-12-01

    Speculation with regard to a permanent lunar base has been with us since Robert Goddard was working on the first liquid-fueled rockets in the 1920's. With the infusion of data from the Apollo Moon flights, a once speculative area of space exploration has become an exciting possibility. A Moon base is not only a very real possibility, but is probably a critical element in the continuation of our piloted space program. This article, originally drafted by World Space Foundation volunteers in conjuction with various academic and research groups, examines some of the strategies involved in selecting an appropriate site for such a lunar base. Site selection involves a number of complex variables, including raw materials for possible rocket propellant generation, hot an cold cycles, view of the sky (for astronomical considerations, among others), geological makeup of the region, and more. This article summarizes the key base siting considerations and suggests some alternatives. Availability of specific resources, including energy and certain minerals, is critical to success.

  12. Cone penetration and bevameter geotechnical tests in lunar regolith simulants: discrete element method analysis and experimentation

    Science.gov (United States)

    Kulchitsky, A. V.; Johnson, J.; Duvoy, P.; Wilkinson, A.; Creager, C. M.

    2012-12-01

    degrees at a controlled speed and measuring the cone tip and sleeve resistance from the penetration of the granular matter. This test was simulated in the COUPi DEM model. Particle size distribution, bulk density, particle-particle contact friction, specific gravity, particle shape, and mechanical properties of every particle were varied to understand how each affect the results. When the important parameters were identified, the parameters of modeled regolith were found that best replicated the experimental data. To find out if the simulations could be translated to different geotechnical tools, a series of bevameter tests were run. The bevameter technique consists of a plate pressure-sinkage test conducted by pressing a disk into the granular aggregate, and a shear test to determine shear stress-displacement properties of regolith. Computer-aided design (CAD) models of the bevameter were imported to the COUPi DEM model. Both plate pressure and shear tests were performed to validate the model. The work presented here is a parametric study to find the most important physical parameters for the DEM, and then adjusting those parameters to converge on the best fit to physical experiments in the two lunar-like soils. Future work will test the parameter set against other experiments, not fit in this work, to see how predictive the tool can be.

  13. E-gravity theory

    OpenAIRE

    Linker, Patrick

    2016-01-01

    A couple of quantum gravity theories were proposed to make theoretical predictions about the behavior of gravity. The most recent approach to quantum gravity, called E-theory, is proposed mathematical, but there is not formulated much about what dynamics of gravity this theory proposes. This research paper treats the main results of the application of E-theory to General relativity involving conservation laws and scattering of particles in presence of gravity. Also the low-energy limit of thi...

  14. Pressurized Lunar Rover (PLR)

    Science.gov (United States)

    Creel, Kenneth; Frampton, Jeffrey; Honaker, David; McClure, Kerry; Zeinali, Mazyar; Bhardwaj, Manoj; Bulsara, Vatsal; Kokan, David; Shariff, Shaun; Svarverud, Eric

    The objective of this project was to design a manned pressurized lunar rover (PLR) for long-range transportation and for exploration of the lunar surface. The vehicle must be capable of operating on a 14-day mission, traveling within a radius of 500 km during a lunar day or within a 50-km radius during a lunar night. The vehicle must accommodate a nominal crew of four, support two 28-hour EVA's, and in case of emergency, support a crew of six when near the lunar base. A nominal speed of ten km/hr and capability of towing a trailer with a mass of two mt are required. Two preliminary designs have been developed by two independent student teams. The PLR 1 design proposes a seven meter long cylindrical main vehicle and a trailer which houses the power and heat rejection systems. The main vehicle carries the astronauts, life support systems, navigation and communication systems, lighting, robotic arms, tools, and equipment for exploratory experiments. The rover uses a simple mobility system with six wheels on the main vehicle and two on the trailer. The nonpressurized trailer contains a modular radioisotope thermoelectric generator (RTG) supplying 6.5 kW continuous power. A secondary energy storage for short-term peak power needs is provided by a bank of lithium-sulfur dioxide batteries. The life support system is partly a regenerative system with air and hygiene water being recycled. A layer of water inside the composite shell surrounds the command center allowing the center to be used as a safe haven during solar flares. The PLR 1 has a total mass of 6197 kg. It has a top speed of 18 km/hr and is capable of towing three metric tons, in addition to the RTG trailer. The PLR 2 configuration consists of two four-meter diameter, cylindrical hulls which are passively connected by a flexible passageway, resulting in the overall vehicle length of 11 m. The vehicle is driven by eight independently suspended wheels. The dual-cylinder concept allows articulated as well as double

  15. Phases of massive gravity

    Science.gov (United States)

    Dubovsky, Sergei L.

    2004-10-01

    We systematically study the most general Lorentz-violating graviton mass invariant under three-dimensional Eucledian group. We find that at general values of mass parameters the massive graviton has six propagating degrees of freedom, and some of them are ghosts or lead to rapid classical instabilities. However, there is a number of different regions in the mass parameter space where massive gravity is described by a consistent low-energy effective theory with cutoff ~ (mMPl)1/2. This theory is free of rapid instabilities and vDVZ discontinuity. Each of these regions is characterized by certain fine-tuning relations between mass parameters, generalizing the Fierz Pauli condition. In some cases the required fine-tunings are consequences of the existence of the subgroups of the diffeomorphism group that are left unbroken by the graviton mass. We found two new cases, when the resulting theories have a property of UV insensitivity, i.e. remain well behaved after inclusion of arbitrary higher dimension operators without assuming any fine-tunings among the coefficients of these operators, besides those enforced by the symmetries. These theories can be thought of as generalizations of the ghost condensate model with a smaller residual symmetry group. We briefly discuss what kind of cosmology can one expect in massive gravity and argue that the allowed values of the graviton mass may be quite large, affecting growth of primordial perturbations, structure formation and, perhaps, enhancing the backreaction of inhomogeneities on the expansion rate of the Universe.

  16. Quantum-gravity effects on a Higgs-Yukawa model

    Science.gov (United States)

    Eichhorn, Astrid; Held, Aaron; Pawlowski, Jan M.

    2016-11-01

    A phenomenologically viable theory of quantum gravity must accommodate all observed matter degrees of freedom and their properties. Here, we explore whether a toy model of the Higgs-Yukawa sector of the Standard Model is compatible with asymptotically safe quantum gravity. We discuss the phenomenological implications of our result in the context of the Standard Model. We analyze the quantum scaling dimension of the system and find an irrelevant Yukawa coupling at a joint gravity-matter fixed point. Further, we explore the impact of gravity-induced couplings between scalars and fermions, which are nonvanishing in asymptotically safe gravity.

  17. Results and Lessons Learned from Performance Testing of Humans in Spacesuits in Simulated Reduced Gravity

    Science.gov (United States)

    Chappell, Steven P.; Norcross, Jason R.; Gernhardt, Michael L.

    2010-01-01

    The Apollo lunar EVA experience revealed challenges with suit stability and control-likely a combination of mass, mobility, and center of gravity (CG) factors. The EVA Physiology, Systems and Performence (EPSP) Project is systematically working with other NASA projects, labs, and facilities to lead a series of studies to understand the role of suit mass, weight, CG, and other parameters on astronaut performance in partial gravity environments.

  18. The Effects of Moon¡¯s Uneven Mass Distribution on the Critical Inclinations of a Lunar Orbiter

    Science.gov (United States)

    Rahoma, Walid A.; Abd El-Salam, Fawzy A.

    2014-12-01

    The uneven mass distribution of the Moon highly perturbs the lunar spacecrafts. This uneven mass distribution leads to peculiar dynamical features of the lunar orbiters. The critical inclination is the value of inclination which keeps the deviation of the argument of pericentre from the initial values to be zero. Considerable investigations have been performed for critical inclination when the gravity field is assumed to be symmetric around the equator, namely for oblate gravity field to which Earth¡¯s satellites are most likely to be subjected. But in the case of a lunar orbiter, the gravity field of mass distribution is rather asymmetric, that is, sectorial, and tesseral, harmonic coefficients are big enough so they can¡¯t be neglected. In the present work, the effects of the first sectorial and tesseral harmonic coefficients in addition to the first zonal harmonic coefficients on the critical inclination of a lunar artificial satellite are investigated. The study is carried out using the Hamiltonian framework. The Hamiltonian of the problem is cconstructed and the short periodic terms are eliminated using Delaunay canonical variables. Considering the above perturbations, numerical simulations for a hypothetical lunar orbiter are presented. Finally, this study reveals that the critical inclination is quite different from the critical inclination of traditional sense and/or even has multiple solutions. Consequently, different families of critical inclination are obtained and analyzed.

  19. Consistent Linearized Gravity in Brane Backgrounds

    CERN Document Server

    Aref'eva, I Ya; Mück, W; Viswanathan, K S; Volovich, I V

    2000-01-01

    A globally consistent treatment of linearized gravity in the Randall-Sundrum background with matter on the brane is formulated. Using a novel gauge, in which the transverse components of the metric are non-vanishing, the brane is kept straight. We analyze the gauge symmetries and identify the physical degrees of freedom of gravity. Our results underline the necessity for non-gravitational confinement of matter to the brane.

  20. Isomonodromic quantization of dimensionally reduced gravity

    OpenAIRE

    Korotkin, D.; Nicolai, H.

    1996-01-01

    We present a detailed account of the isomonodromic quantization of dimensionally reduced Einstein gravity with two commuting Killing vectors. This theory constitutes an integrable ``midi-superspace" version of quantum gravity with infinitely many interacting physical degrees of freedom. The canonical treatment is based on the complete separation of variables in the isomonodromic sectors of the model. The Wheeler-DeWitt and diffeomorphism constraints are thereby reduced to the Knizhnik-Zamolod...

  1. The Lunar Volatiles Orbiter: A Discovery Class Lunar Water Mission

    Science.gov (United States)

    Lucey, P. G.; Sun, X.; Petro, N.; Farrell, W.; Abshire, J. B.; Mazarico, E.; Neumann, G. A.; Green, R.; Thompson, D. E.; Greenberger, R.; Hurley, D.; McClanahan, T. P.; Smith, D. E.; Zuber, M. T.

    2016-11-01

    The Lunar Volatiles Orbiter is a Discovery Class mission concept aimed at characterizing the nature and mobility of water on the Moon. Its instruments include a laser spectrometer, an infrared hyperspectral imager, and a neutral mass spectrometer.

  2. Implications of Lunar Prospector Data for Lunar Geophysics

    Science.gov (United States)

    Zuber, Maria

    2003-01-01

    Research is sumamrized in the following areas: The Asymmetric Thermal Evolution of the Moon; Magma Transport Process on the Moon;The Composition and Origin of the Deep Lunar Crust;The Redistribution of Thorium on the Moon's Surface.

  3. Lunar resources: possibilities for utilization

    Science.gov (United States)

    Shevchenko, Vladislav

    Introduction: With the current advanced orbiters sent to the Moon by the United States, Europe, Japan, China, and India, we are opening a new era of lunar studies. The International Academy of Aeronautics (IAA) has begun a study on opportunities and challenges of developing and using space mineral resources (SRM). This study will be the first international interdisciplinary assessment of the technology, economics and legal aspects of using space mineral resources for the benefit of humanity. The IAA has approved a broad outline of areas that the study will cover including type, location and extent of space mineral resources on the Moon, asteroids and others. It will be studied current technical state of the art in the identification, recovery and use of SRM in space and on the Earth that identifies all required technical processes and systems, and that makes recommendations for specific technology developments that should be addressed near term at the system and subsystem level to make possible prospecting, mineral extraction, beneficiation, transport, delivery and use of SMR. Particular attention will be dedicated to study the transportation and retrieval options available for SRM. Lunar polar volatile: ROSCOSMOS places a high priority on studying lunar polar volatiles, and has outlined a few goals related to the study of such volatiles. Over the course of several years, NASA’s Lunar Reconnaissance Orbiter scanned the Moon’s South Pole using its Lunar Exploration Neutron Detector (LEND - IKI Russia) to measure how much hydrogen is trapped within the lunar soil. Areas exhibiting suppressed neutron activity indicate where hydrogen atoms are concentrated most, strongly suggesting the presence of water molecules. Current survey of the Moon’s polar regions integrated geospatial data for topography, temperature, and hydrogen abundances from Lunar Reconnaissance Orbiter, Chandrayaan-1, and Lunar Prospector to identify several landing sites near both the North and

  4. A new lunar digital elevation model from the Lunar Orbiter Laser Altimeter and SELENE Terrain Camera

    Science.gov (United States)

    Barker, M. K.; Mazarico, E.; Neumann, G. A.; Zuber, M. T.; Haruyama, J.; Smith, D. E.

    2016-07-01

    We present an improved lunar digital elevation model (DEM) covering latitudes within ±60°, at a horizontal resolution of 512 pixels per degree (∼60 m at the equator) and a typical vertical accuracy ∼3 to 4 m. This DEM is constructed from ∼ 4.5 ×109 geodetically-accurate topographic heights from the Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter, to which we co-registered 43,200 stereo-derived DEMs (each 1° × 1°) from the SELENE Terrain Camera (TC) (∼1010 pixels total). After co-registration, approximately 90% of the TC DEMs show root-mean-square vertical residuals with the LOLA data of profiles (typically amounting to <10 m horizontally and <1 m vertically). By combining both co-registered datasets, we obtain a near-global DEM with high geodetic accuracy, and without the need for surface interpolation. We evaluate the resulting LOLA + TC merged DEM (designated as "SLDEM2015") with particular attention to quantifying seams and crossover errors.

  5. A New Lunar Digital Elevation Model from the Lunar Orbiter Laser Altimeter and SELENE Terrain Camera

    Science.gov (United States)

    Barker, M. K.; Mazarico, E.; Neumann, G. A.; Zuber, M. T.; Haruyama, J.; Smith, D. E.

    2015-01-01

    We present an improved lunar digital elevation model (DEM) covering latitudes within +/-60 deg, at a horizontal resolution of 512 pixels per degree ( approx.60 m at the equator) and a typical vertical accuracy approx.3 to 4 m. This DEM is constructed from approx.4.5 ×10(exp 9) geodetically-accurate topographic heights from the Lunar Orbiter Laser Altimeter (LOLA) onboard the Lunar Reconnaissance Orbiter, to which we co-registered 43,200 stereo-derived DEMs (each 1 deg×1 deg) from the SELENE Terrain Camera (TC) ( approx.10(exp 10) pixels total). After co-registration, approximately 90% of the TC DEMs show root-mean-square vertical residuals with the LOLA data of < 5 m compared to approx.50% prior to co-registration. We use the co-registered TC data to estimate and correct orbital and pointing geolocation errors from the LOLA altimetric profiles (typically amounting to < 10 m horizontally and < 1 m vertically). By combining both co-registered datasets, we obtain a near-global DEM with high geodetic accuracy, and without the need for surface interpolation. We evaluate the resulting LOLA + TC merged DEM (designated as "SLDEM2015") with particular attention to quantifying seams and crossover errors.

  6. Prospecting for lunar resources

    Science.gov (United States)

    Taylor, G.; Martel, L.

    Large space settlements on the Moon (thousands of people) will require use of indigenous resources to build and maintain the infrastructure and generate products for export. Prospecting for these resources is a crucial step in human migration to space and needs to begin before settlement and the establishment of industrial complexes. We are devising a multi-faceted approach to prospect for resources. A central part of this work is developing the methodology for prospecting the Moon and other planetary bodies. This involves a number of investigations: (1) It is essential to analyze the economics of planetary ore deposits. Ore deposits are planetary materials that we can mine, process, and deliver to customers at a profit. The planetary context tosses in some interesting twists to this definition. (2) We are also making a comprehensive theoretical assessment of potential lunar ore deposits. Our understanding of the compositions, geological histories, and geological processes on the Moon will lead to significant differences in how we assess wh a t types of ores could be present. For example, the bone-dry nature of the Moon (except at the poles) eliminates all ore deposits associated with hydrothermal fluids. (3) We intend to search for resources using existing data for the Moon. Thus, prospecting can begin immediately. We have a wealth of remote sensing data for the Moon. We also have a good sampling of the Moon by the Apollo and Luna missions, and from lunar meteorites. We can target specific types of deposits already identified (e.g. lunar pyroclastic deposits) and look for other geological settings that might have produced ores and other materials of economic value. Another approach we will take is to examine all data available to look for anomalies. Examples are unusual spectral properties, large disagreements between independent techniques that measure the same property, unusual elemental ratios, or simply exceptional properties such as elemental abundances much

  7. MOONLIGHT: A NEW LUNAR LASER RANGING RETROREFLECTOR AND THE LUNAR GEODETIC PRECESSION

    Directory of Open Access Journals (Sweden)

    M. Martini

    2013-12-01

    temperature distribution of retroreflector payloads under thermal conditions produced with a close-match solar simulator. The apparatus includes infrared cameras for non-invasive thermometry, thermal control and real-time payload movement to simulate satellite orientation on orbit with respect to solar illumination and laser interrogation beams. These capabilities provide: unique pre-launch performance validation of the space segment of LLR/SLR (Satellite Laser Ranging; retroreflector design optimization to maximize ranging efficiency and signal-to-noise conditions in daylight. Results of the SCF-Test of our CCR payload will be presented. Negotiations are underway to propose our payload and SCF-Test services for precision gravity and lunar science measurements with next robotic lunar landing missions. In particular, a scientific collaboration agreement was signed on Jan. 30, 2012, by D. Currie, S. Dell’Agnello and the Japanese PI team of the LLR instrument of the proposed SELENE-2 mission by JAXA (Registered with INFN Protocol n. 0000242-03/Feb/2012. The agreement foresees that, under no exchange of funds, the Japanese single, large, hollow LLR reflector will be SCF-Tested and that MoonLIGHT will be considered as backup instrument.

  8. Lunar Soil Particle Separator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS improves ISRU oxygen...

  9. Lunar Organic Waste Reformer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Organic Waste Reformer (LOWR) utilizes high temperature steam reformation to convert all plastic, paper, and human waste materials into useful gases. In...

  10. Google Moon Lunar Mapping Data

    Data.gov (United States)

    National Aeronautics and Space Administration — A collection of lunar maps and charts. This tool is an exciting new way to explore the story of the Apollo missions, still the only time mankind has set foot on...

  11. The enigma of lunar magnetism

    Science.gov (United States)

    Hood, L. L.

    1981-01-01

    Current understandings of the nature and probable origin of lunar magnetism are surveyed. Results of examinations of returned lunar samples are discussed which reveal the main carrier of the observed natural remanent magnetization to be iron, occasionally alloyed with nickel and cobalt, but do not distinguish between thermoremanent and shock remanent origins, and surface magnetometer data is presented, which indicates small-scale magnetic fields with a wide range of field intensities implying localized, near-surface sources. A detailed examination is presented of orbital magnetometer and charged particle data concerning the geologic nature and origin of magnetic anomaly sources and the directional properties of the magnetization, which exhibit a random distribution except for a depletion in the north-south direction. A lunar magnetization survey with global coverage provided by a polar orbiting satellite is suggested as a means of placing stronger constraints on the origin of lunar crustal magnetization.

  12. Lunar Soil Particle Separator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Soil Particle Separator (LSPS) is an innovative method to beneficiate soil prior to in-situ resource utilization (ISRU). The LSPS can improve ISRU oxygen...

  13. Lunar Organic Waste Reformer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Organic Waste Reformer (LOWR) utilizes high temperature steam reformation to convert all plastic, paper, and human waste materials into useful gases. In...

  14. Lunar Probe Reaches Deep Space

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    @@ China's second lunar probe, Chang'e-2, has reached an orbit 1.5 million kilometers from Earth for an additional mission of deep space exploration, the State Administration for Science, Technology and Industry for National Defense announced.

  15. Lunar Core Drive Tubes Summary

    Data.gov (United States)

    National Aeronautics and Space Administration — Contains a brief summary and high resolution imagery from various lunar rock and core drive tubes collected from the Apollo and Luna missions to the moon.

  16. Early lunar magnetism

    Science.gov (United States)

    Banerjee, S. K.; Mellema, J. P.

    1976-01-01

    A new method (Shaw, 1974) for investigating paleointensity (the ancient magnetic field) was applied to three subsamples of a single, 1-m homogeneous clast from a recrystallized boulder of lunar breccia. Several dating methods established 4 billion years as the age of boulder assembly. Results indicate that the strength of the ambient magnetic field at the Taurus-Littrow region of the moon was about 0.4 oersted at 4 billion years ago. Values as high as 1.2 oersted have been reported (Collison et al., 1973). The required fields are approximately 10,000 times greater than present interplanetary or solar flare fields. It is suggested that this large field could have arisen from a pre-main sequence T-Tauri sun.

  17. Electrochemistry of lunar rocks

    Science.gov (United States)

    Lindstrom, D. J.; Haskin, L. A.

    1979-01-01

    Electrolysis of silicate melts has been shown to be an effective means of producing metals from common silicate materials. No fluxing agents need be added to the melts. From solution in melts of diopside (CaMgSi2O6) composition, the elements Si, Ti, Ni, and Fe have been reduced to their metallic states. Platinum is a satisfactory anode material, but other cathode materials are needed. Electrolysis of compositional analogs of lunar rocks initially produces iron metal at the cathode and oxygen gas at the anode. Utilizing mainly heat and electricity which are readily available from sunlight, direct electrolysis is capable of producing useful metals from common feedstocks without the need for expendable chemicals. This simple process and the products obtained from it deserve further study for use in materials processing in space.

  18. The lunar dynamo.

    Science.gov (United States)

    Weiss, Benjamin P; Tikoo, Sonia M

    2014-12-05

    The inductive generation of magnetic fields in fluid planetary interiors is known as the dynamo process. Although the Moon today has no global magnetic field, it has been known since the Apollo era that the lunar rocks and crust are magnetized. Until recently, it was unclear whether this magnetization was the product of a core dynamo or fields generated externally to the Moon. New laboratory and spacecraft measurements strongly indicate that much of this magnetization is the product of an ancient core dynamo. The dynamo field persisted from at least 4.25 to 3.56 billion years ago (Ga), with an intensity reaching that of the present Earth. The field then declined by at least an order of magnitude by ∼3.3 Ga. The mechanisms for sustaining such an intense and long-lived dynamo are uncertain but may include mechanical stirring by the mantle and core crystallization.

  19. International lunar observatory / power station: from Hawaii to the Moon

    Science.gov (United States)

    Durst, S.

    Astronomy's great advantages from the Moon are well known - stable surface, diffuse atmosphere, long cool nights (14 days), low gravity, far side radio frequency silence. A large variety of astronomical instruments and observations are possible - radio, optical and infrared telescopes and interferometers; interferometry for ultra- violet to sub -millimeter wavelengths and for very long baselines, including Earth- Moon VLBI; X-ray, gamma-ray, cosmic ray and neutrino detection; very low frequency radio observation; and more. Unparalleled advantages of lunar observatories for SETI, as well as for local surveillance, Earth observation, and detection of Earth approaching objects add significant utility to lunar astronomy's superlatives. At least nine major conferences in the USA since 1984 and many elsewhere, as well as ILEWG, IAF, IAA, LEDA and other organizations' astronomy-from-the-Moon research indicate a lunar observatory / power station, robotic at first, will be one of the first mission elements for a permanent lunar base. An international lunar observatory will be a transcending enterprise, highly principled, indispensable, soundly and broadly based, and far- seeing. Via Astra - From Hawaii to the Moon: The astronomy and scie nce communities, national space agencies and aerospace consortia, commercial travel and tourist enterprises and those aspiring to advance humanity's best qualities, such as Aloha, will recognize Hawaii in the 21st century as a new major support area and pan- Pacific port of embarkation to space, the Moon and beyond. Astronomical conditions and facilities on Hawaii's Mauna Kea provide experience for construction and operation of observatories on the Moon. Remote and centrally isolated, with diffuse atmosphere, sub-zero temperature and limited working mobility, the Mauna Kea complex atop the 4,206 meter summit of the largest mountain on the planet hosts the greatest collection of large astronomical telescopes on Earth. Lunar, extraterrestrial

  20. Adsorption of Water on JSC-1A Lunar Simulant Samples

    Science.gov (United States)

    Goering, John; Sah, Shweta; Burghaus, Uwe; Street, Kenneth W.

    2008-01-01

    Remote sensing probes sent to the moon in the 1990s indicated that water may exist in areas such as the bottoms of deep, permanently shadowed craters at the lunar poles, buried under regolith. Water is of paramount importance for any lunar exploration and colonization project which would require self-sustainable systems. Therefore, investigating the interaction of water with lunar regolith is pertinent to future exploration. The lunar environment can be approximated in ultra-high vacuum systems such as those used in thermal desorption spectroscopy (TDS). Questions about water dissociation, surface wetting, degree of crystallization, details of water-ice transitions, and cluster formation kinetics can be addressed by TDS. Lunar regolith specimens collected during the Apollo missions are still available though precious, so testing with simulant is required before applying to use lunar regolith samples. Hence, we used for these studies JSC-1a, mostly an aluminosilicate glass and basaltic material containing substantial amounts of plagioclase, some olivine and traces of other minerals. Objectives of this project include: 1) Manufacturing samples using as little raw material as possible, allowing the use of surface chemistry and kinetics tools to determine the feasibility of parallel studies on regolith, and 2) Characterizing the adsorption kinetics of water on the regolith simulant. This has implications for the probability of finding water on the moon and, if present, for recovery techniques. For condensed water films, complex TDS data were obtained containing multiple features, which are related to subtle rearrangements of the water adlayer. Results from JSC-1a TDS studies indicate: 1) Water dissociation on JSC-1a at low exposures, with features detected at temperatures as high as 450 K and 2) The formation of 3D water clusters and a rather porous condensed water film. It appears plausible that the sub- m sized particles act as nucleation centers.

  1. Using Lunar Module Shadows To Scale the Effects of Rocket Exhaust Plumes

    Science.gov (United States)

    2008-01-01

    Excavating granular materials beneath a vertical jet of gas involves several physical mechanisms. These occur, for example, beneath the exhaust plume of a rocket landing on the soil of the Moon or Mars. We performed a series of experiments and simulations (Figure 1) to provide a detailed view of the complex gas-soil interactions. Measurements taken from the Apollo lunar landing videos (Figure 2) and from photographs of the resulting terrain helped demonstrate how the interactions extrapolate into the lunar environment. It is important to understand these processes at a fundamental level to support the ongoing design of higher fidelity numerical simulations and larger-scale experiments. These are needed to enable future lunar exploration wherein multiple hardware assets will be placed on the Moon within short distances of one another. The high-velocity spray of soil from the landing spacecraft must be accurately predicted and controlled or it could erode the surfaces of nearby hardware. This analysis indicated that the lunar dust is ejected at an angle of less than 3 degrees above the surface, the results of which can be mitigated by a modest berm of lunar soil. These results assume that future lunar landers will use a single engine. The analysis would need to be adjusted for a multiengine lander. Figure 3 is a detailed schematic of the Lunar Module camera calibration math model. In this chart, formulas relating the known quantities, such as sun angle and Lunar Module dimensions, to the unknown quantities are depicted. The camera angle PSI is determined by measurement of the imaged aspect ratio of a crater, where the crater is assumed to be circular. The final solution is the determination of the camera calibration factor, alpha. Figure 4 is a detailed schematic of the dust angle math model, which again relates known to unknown parameters. The known parameters now include the camera calibration factor and Lunar Module dimensions. The final computation is the ejected

  2. Lunar Gene Bank for Endangered Species

    Science.gov (United States)

    Swain, Ramakrushna

    2016-07-01

    Introduction: Before the dawn of the 22nd century, we face the huge risk of losing our genetic heritage accumulated during aeons of evolution. The losses include hundreds of vertebrates, human gene pools, hundreds of thousands of plants and over a million insect species. As we have observed, adequate conservation of habitat is unfeasible and active breeding programs cover only a handful of the many thousand species threatened. We propose cryopreservation of germplasms by constructing a cDNA library based gene bank for endangered species in the permanently shadowed polar lunar craters that would provide immunity from both natural disadvantages and humanitarian intrusions. Rationale: Under such alarming circumstances, we turned to cryopreservation as an option but over thousands of years economic depression, sabotage, conflicts, warfare or even a brief disruption to the precise cryopreservation can hamper the storage of genetic samples.When we are considering conservation it is always preferable to go for a more secure and permanent solution. It was found out that the climatic and strategic location of the lunar polar craters are adequately hospitable, remote and free of maintenance and human observation as they provide naturally cryogenic temperature, reduced gravity and vacuum environment, non-reactive surface, safety from celestial intrusion and permanent shadow which doesn't allow the temperature to fluctuate thus providing most suitable storage facilities for the germplasms. PSRs provide steady temperature of 40- 60K and immunity to earthquakes due to low seismic activity. At these sites, burial in one meter or more of the regolith will provide protection against the solar wind, solar and galactic cosmic rays and micrometeorite impact. It provides the minimum necessary barrier from human intervention and at the same time enables easy retrieval for future usage. Genetic samples of endangered species can enable restoration even after its extinction. Preserved

  3. Lunar Navigation Architecture Design Considerations

    Science.gov (United States)

    D'Souza, Christopher; Getchius, Joel; Holt, Greg; Moreau, Michael

    2009-01-01

    The NASA Constellation Program is aiming to establish a long-term presence on the lunar surface. The Constellation elements (Orion, Altair, Earth Departure Stage, and Ares launch vehicles) will require a lunar navigation architecture for navigation state updates during lunar-class missions. Orion in particular has baselined earth-based ground direct tracking as the primary source for much of its absolute navigation needs. However, due to the uncertainty in the lunar navigation architecture, the Orion program has had to make certain assumptions on the capabilities of such architectures in order to adequately scale the vehicle design trade space. The following paper outlines lunar navigation requirements, the Orion program assumptions, and the impacts of these assumptions to the lunar navigation architecture design. The selection of potential sites was based upon geometric baselines, logistical feasibility, redundancy, and abort support capability. Simulated navigation covariances mapped to entry interface flightpath- angle uncertainties were used to evaluate knowledge errors. A minimum ground station architecture was identified consisting of Goldstone, Madrid, Canberra, Santiago, Hartebeeshoek, Dongora, Hawaii, Guam, and Ascension Island (or the geometric equivalent).

  4. 3-D inversion of gravity data in spherical coordinates with application to the GRAIL data

    Science.gov (United States)

    Liang, Qing; Chen, Chao; Li, Yaoguo

    2014-06-01

    Three-dimensional (3-D) inversion of gravity data has been widely used to reconstruct the density distributions of ore bodies, basins, crust, lithosphere, and upper mantle. For global model of 3-D density structures of planetary interior, such as the Earth, the Moon, or Mars, it is necessary to use an inversion algorithm that operates in the spherical coordinates. We develop a 3-D inversion algorithm formulated with specially designed model objective function and radial weighting function in the spherical coordinates. We present regional and global synthetic examples to illustrate the capability of the algorithm. The inverted results show density distribution features consistent with the true models. We also apply the algorithm to a set of lunar Bouguer gravity anomaly derived from the Gravity Recovery and Interior Laboratory (GRAIL) gravity field and obtain a lunar 3-D density distribution. High-density anomalies are clearly identified underlying lunar basins, a wide region of the lateral density heterogeneities that exist beneath the South Pole-Aitken basin are found, and low-density anomalies are distributed beneath the Feldspathic Highlands Terrane on the lunar far-side. The consistency of these results with those obtained independently from other existing methods verifies the newly developed algorithm.

  5. APOLLO: A new push in solar-system tests of gravity

    Science.gov (United States)

    Murphy, T. W.; Adelberger, E. G.; Battat, J. B. R.; Hoyle, C. D.; McMillan, R. J.; Michelsen, E. L.; Stubbs, C. W.; Swanson, H. E.

    2010-01-01

    Lunar laser ranging (LLR) has long provided many of our best measurements on the fundamental nature of gravity, including the strong equivalence principle, time -rate-of-change of the gravitational constant, the inverse square law, geodetic precession, and gravitomagnetism. This paper serves as a brief overview of APOLLO: a recently operational LLR experiment capable of millimeter-level range precision.

  6. Altair Lunar Lander Development Status: Enabling Human Lunar Exploration

    Science.gov (United States)

    Laurini, Kathleen C.; Connolly, John F.

    2009-01-01

    As a critical part of the NASA Constellation Program lunar transportation architecture, the Altair lunar lander will return humans to the moon and enable a sustained program of lunar exploration. The Altair is to deliver up to four crew to the surface of the moon and return them to low lunar orbit at the completion of their mission. Altair will also be used to deliver large cargo elements to the lunar surface, enabling the buildup of an outpost. The Altair Project initialized its design using a minimum functionality approach that identified critical functionality required to meet a minimum set of Altair requirements. The Altair team then performed several analysis cycles using risk-informed design to selectively add back components and functionality to increase the vehicles safety and reliability. The analysis cycle results were captured in a reference Altair design. This design was reviewed at the Constellation Lunar Capabilities Concept Review, a Mission Concept Review, where key driving requirements were confirmed and the Altair Project was given authorization to begin Phase A project formulation. A key objective of Phase A is to revisit the Altair vehicle configuration, to better optimize it to complete its broad range of crew and cargo delivery missions. Industry was invited to partner with NASA early in the design to provide their insights regarding Altair configuration and key engineering challenges. A blended NASA-industry team will continue to refine the lander configuration and mature the vehicle design over the next few years. This paper will update the international community on the status of the Altair Project as it addresses the challenges of project formulation, including optimizing a vehicle configuration based on the work of the NASA Altair Project team, industry inputs and the plans going forward in designing the Altair lunar lander.

  7. Altair Lunar Lander Development Status: Enabling Human Lunar Exploration

    Science.gov (United States)

    Laurini, Kathleen C.; Connolly, John F.

    2009-01-01

    As a critical part of the NASA Constellation Program lunar transportation architecture, the Altair lunar lander will return humans to the moon and enable a sustained program of lunar exploration. The Altair is to deliver up to four crew to the surface of the moon and return them to low lunar orbit at the completion of their mission. Altair will also be used to deliver large cargo elements to the lunar surface, enabling the buildup of an outpost. The Altair Project initialized its design using a minimum functionality approach that identified critical functionality required to meet a minimum set of Altair requirements. The Altair team then performed several analysis cycles using risk-informed design to selectively add back components and functionality to increase the vehicles safety and reliability. The analysis cycle results were captured in a reference Altair design. This design was reviewed at the Constellation Lunar Capabilities Concept Review, a Mission Concept Review, where key driving requirements were confirmed and the Altair Project was given authorization to begin Phase A project formulation. A key objective of Phase A is to revisit the Altair vehicle configuration, to better optimize it to complete its broad range of crew and cargo delivery missions. Industry was invited to partner with NASA early in the design to provide their insights regarding Altair configuration and key engineering challenges. A blended NASA-industry team will continue to refine the lander configuration and mature the vehicle design over the next few years. This paper will update the international community on the status of the Altair Project as it addresses the challenges of project formulation, including optimizing a vehicle configuration based on the work of the NASA Altair Project team, industry inputs and the plans going forward in designing the Altair lunar lander.

  8. Chang'E-1 orbiter discovers a lunar nearside volcano: YUTU Mountain

    Institute of Scientific and Technical Information of China (English)

    PING dinSong; HUANG Qian; SU XiaoLi; TANG GeShi; SHU Rong; XIAO Long; HUANG Jun

    2009-01-01

    In the day time of the Moon surface, the strong illumination from high altitude and high albedo rate radical craters will introduce the illumination effect on observing the nearby low altitude, low albedo rate and shallow small slop rate area seriously, and even can "hide" the later area from the light. Based on the lunar global topography model obtained by Chang'E-1 mission, and by comparing with the lunar gravity model, a volcano named "YUTU Mountain" has been identified. It is a volcano with diameter of ~300 km and height of ~2 km located at (14°N, 308°E) in Oceanus Procellarum. Besides, the DEM of another volcano named "GUISHU Mountain" in the same area has been improved. This new discovery will benefit the study of lunar magmatism and volcanism evolution in the nearside of the Moon.

  9. Analysis of Orbit Perturbations and Frozen Orbit for Lunar Satellite%月球卫星轨道摄动及冻结轨道研究

    Institute of Scientific and Technical Information of China (English)

    童科伟; 刘伟; 高朝辉; 王俊峰; 王笃俊

    2012-01-01

    利用理论分析、数值仿真与相图分析,论述了月球卫星冻结轨道与地球卫星冻结轨道的区别,分析结果表明,月球重力场存在较大异常,会引起月球卫星轨道发生较大漂移。月球冻结轨道在田谐项影响下,还存在中等周期的漂移。仅简单考虑带谐项系数,无法求得完美的月球冻结系数。月球重力场异常对绕月卫星的影响与地球相比存在很大区别。月球轨道卫星的长期运行与控制策略的设计,不能按照地球轨道卫星的传统方法。目前使用的月球引力模型精度较差,尽管基于这些不可靠的引力模型,可以得出很多有用结论,但对未来高精度的月球探测任务来说,还存在不足,需要在将来的月球探测任务中,探测高精度的月球重力场,以利于未来月球探测航天系统的任务分析与设计。%The differences between lunar satellite frozen orbit and earth satellite frozen orbit are analyzed based on analytic theory,numerical simulation and phase portrait analysis.The results show that the lunar gravity anomaly causes large drift of lunar satellite orbit,the lunar tesseral harmonics causes middle period drift of lunar frozen orbit.Phase portrait analysis and numerical analysis methods can be used to solve perfect lunar frozen coefficients instead of only using zonal harmonics.Lunar gravity anomaly causes significant difference when compared with earth orbit.For long term operation and control of lunar satellite a different strategy must be used.Though some useful results can be obtained based on currently used lower precision lunar gravity field models,they are not adequate for the future high precision lunar exploration mission.It is urgent to detect high precision lunar gravity field model for the mission analysis and design of future lunar exploration space system.

  10. Urine specific gravity test

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003587.htm Urine specific gravity test To use the sharing features on this page, please enable JavaScript. Urine specific gravity is a laboratory test that shows the concentration ...

  11. Idaho State Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (24,284 records) were compiled by the U. S. Geological Survey. This data base was received on February 23, 1993. Principal gravity...

  12. Northern Oklahoma Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (710 records) were compiled by Professor Ahern. This data base was received in June 1992. Principal gravity parameters include latitude,...

  13. Andes 1997 Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Central Andes gravity data (6,151 records) were compiled by Professor Gotze and the MIGRA Group. This data base was received in April, 1997. Principal gravity...

  14. DNAG Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Decade of North American Geology (DNAG) gravity grid values, spaced at 6 km, were used to produce the Gravity Anomaly Map of North America (1987; scale...

  15. Cadiz, California Gravity Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (32 records) were gathered by Mr. Seth I. Gutman for AridTech Inc., Denver, Colorado using a Worden Prospector gravity meter. This data base...

  16. Classical Weyl Transverse Gravity

    CERN Document Server

    Oda, Ichiro

    2016-01-01

    We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally-invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally-invariant scalar tensor gravity and the WTDiff gravity is a "fake" symmetry. We find it possible to extend this proof to all matter fields,...

  17. Bubble Growth in Lunar Basalts

    Science.gov (United States)

    Zhang, Y.

    2009-05-01

    Although Moon is usually said to be volatile-"free", lunar basalts are often vesicular with mm-size bubbles. The vesicular nature of the lunar basalts suggests that they contained some initial gas concentration. A recent publication estimated volatile concentrations in lunar basalts (Saal et al. 2008). This report investigates bubble growth on Moon and compares with that on Earth. Under conditions relevant to lunar basalts, bubble growth in a finite melt shell (i.e., growth of multiple regularly-spaced bubbles) is calculated following Proussevitch and Sahagian (1998) and Liu and Zhang (2000). Initial H2O content of 700 ppm (Saal et al. 2008) or lower is used and the effect of other volatiles (such as carbon dioxide, halogens, and sulfur) is ignored. H2O solubility at low pressures (Liu et al. 2005), concentration-dependent diffusivity in basalt (Zhang and Stolper 1991), and lunar basalt viscosity (Murase and McBirney 1970) are used. Because lunar atmospheric pressure is essentially zero, the confining pressure on bubbles is completely supplied by the overlying magma. Due to low H2O content in lunar basaltic melt (700 ppm H2O corresponds to a saturation pressure of 75 kPa), H2O bubbles only grow in the upper 16 m of a basalt flow or lake. A depth of 20 mm corresponds to a confining pressure of 100 Pa. Hence, vesicular lunar rocks come from very shallow depth. Some findings from the modeling are as follows. (a) Due to low confining pressure as well as low viscosity, even though volatile concentration is very low, bubble growth rate is extremely high, much higher than typical bubble growth rates in terrestrial melts. Hence, mm-size bubbles in lunar basalts are not strange. (b) Because the pertinent pressures are so low, bubble pressure due to surface tension plays a main role in lunar bubble growth, contrary to terrestrial cases. (c) Time scale to reach equilibrium bubble size increases as the confining pressure increases. References: (1) Liu Y, Zhang YX (2000) Earth

  18. Experimental Evaluation of the Scale Model Method to Simulate Lunar Vehicle Dynamics

    Science.gov (United States)

    Johnson, Kyle; Asnani, Vivake; Polack, Jeff; Plant, Mark

    2016-01-01

    As compared to driving on Earth, the presence of lower gravity and uneven terrain on planetary bodies makes high speed driving difficult. In order to maintain ground contact and control vehicles need to be designed with special attention to dynamic response. The challenge of maintaining control on the Moon was evident during high speed operations of the Lunar Roving Vehicle (LRV) on Apollo 16, as at one point all four tires were off the ground; this event has been referred to as the Lunar Grand Prix. Ultimately, computer simulation should be used to examine these phenomena during the vehicle design process; however, experimental techniques are required for the validation and elucidation of key issues. The objectives of this study were to evaluate the methodology for developing a scale model of a lunar vehicle using similitude relationships and to test how vehicle configuration, six or eight wheel pods, and local tire compliance, soft or stiff, affect the vehicles dynamic performance. A wheel pod consists of a drive and steering transmission and wheel. The Lunar Electric Rover (LER), a human driven vehicle with a pressurized cabin, was selected as an example for which a scale model was built. The scaled vehicle was driven over an obstacle and the dynamic response was observed and then scaled to represent the full-size vehicle in lunar gravity. Loss of ground contact, in terms of vehicle travel distance with tires off the ground, was examined. As expected, local tire compliance allowed ground contact to be maintained over a greater distance. However, switching from a six-tire configuration to an eight-tire configuration with reduced suspension stiffness had a negative effect on ground contact. It is hypothesized that this was due to the increased number or frequency of impacts. The development and testing of this scale model provided practical lessons for future low-gravity vehicle development.

  19. Fab 5: Noncanonical Kinetic Gravity, Self Tuning, and Cosmic Acceleration

    CERN Document Server

    Appleby, Stephen A; Linder, Eric V

    2012-01-01

    We investigate circumstances under which one can generalize Horndeski's most general scalar-tensor theory of gravity. Specifically we demonstrate that a nonlinear combination of purely kinetic gravity terms can give rise to an accelerating universe without the addition of extra propagating degrees of freedom on cosmological backgrounds, and exhibit self tuning to bring a large cosmological constant under control. This nonlinear approach leads to new properties that may be instructive for exploring the behaviors of gravity.

  20. Physics of Artificial Gravity

    Science.gov (United States)

    Bukley, Angie; Paloski, William; Clement, Gilles

    2006-01-01

    This chapter discusses potential technologies for achieving artificial gravity in a space vehicle. We begin with a series of definitions and a general description of the rotational dynamics behind the forces ultimately exerted on the human body during centrifugation, such as gravity level, gravity gradient, and Coriolis force. Human factors considerations and comfort limits associated with a rotating environment are then discussed. Finally, engineering options for designing space vehicles with artificial gravity are presented.

  1. Terrestrial Gravity Fluctuations

    Science.gov (United States)

    Harms, Jan

    2015-12-01

    Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10-23 Hz-1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of

  2. Terrestrial Gravity Fluctuations.

    Science.gov (United States)

    Harms, Jan

    2015-01-01

    Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW) detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10(-23) Hz(-1/2) above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of

  3. Terrestrial Gravity Fluctuations

    Directory of Open Access Journals (Sweden)

    Jan Harms

    2015-12-01

    Full Text Available Different forms of fluctuations of the terrestrial gravity field are observed by gravity experiments. For example, atmospheric pressure fluctuations generate a gravity-noise foreground in measurements with super-conducting gravimeters. Gravity changes caused by high-magnitude earthquakes have been detected with the satellite gravity experiment GRACE, and we expect high-frequency terrestrial gravity fluctuations produced by ambient seismic fields to limit the sensitivity of ground-based gravitational-wave (GW detectors. Accordingly, terrestrial gravity fluctuations are considered noise and signal depending on the experiment. Here, we will focus on ground-based gravimetry. This field is rapidly progressing through the development of GW detectors. The technology is pushed to its current limits in the advanced generation of the LIGO and Virgo detectors, targeting gravity strain sensitivities better than 10^–23 Hz^–1/2 above a few tens of a Hz. Alternative designs for GW detectors evolving from traditional gravity gradiometers such as torsion bars, atom interferometers, and superconducting gradiometers are currently being developed to extend the detection band to frequencies below 1 Hz. The goal of this article is to provide the analytical framework to describe terrestrial gravity perturbations in these experiments. Models of terrestrial gravity perturbations related to seismic fields, atmospheric disturbances, and vibrating, rotating or moving objects, are derived and analyzed. The models are then used to evaluate passive and active gravity noise mitigation strategies in GW detectors, or alternatively, to describe their potential use in geophysics. The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our

  4. Terrestrial Gravity Fluctuations

    CERN Document Server

    Harms, Jan

    2015-01-01

    The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of terrestrial gravity fluctuations will have great impact on the future development of GW detectors and high-precision gravimetry in general, and many open questions need to be answered still as emphasized in this article.

  5. Lunar Meteorites: A Global Geochemical Dataset

    Science.gov (United States)

    Zeigler, R. A.; Joy, K. H.; Arai, T.; Gross, J.; Korotev, R. L.; McCubbin, F. M.

    2017-01-01

    To date, the world's meteorite collections contain over 260 lunar meteorite stones representing at least 120 different lunar meteorites. Additionally, there are 20-30 as yet unnamed stones currently in the process of being classified. Collectively these lunar meteorites likely represent 40-50 distinct sampling locations from random locations on the Moon. Although the exact provenance of each individual lunar meteorite is unknown, collectively the lunar meteorites represent the best global average of the lunar crust. The Apollo sites are all within or near the Procellarum KREEP Terrane (PKT), thus lithologies from the PKT are overrepresented in the Apollo sample suite. Nearly all of the lithologies present in the Apollo sample suite are found within the lunar meteorites (high-Ti basalts are a notable exception), and the lunar meteorites contain several lithologies not present in the Apollo sample suite (e.g., magnesian anorthosite). This chapter will not be a sample-by-sample summary of each individual lunar meteorite. Rather, the chapter will summarize the different types of lunar meteorites and their relative abundances, comparing and contrasting the lunar meteorite sample suite with the Apollo sample suite. This chapter will act as one of the introductory chapters to the volume, introducing lunar samples in general and setting the stage for more detailed discussions in later more specialized chapters. The chapter will begin with a description of how lunar meteorites are ejected from the Moon, how deep samples are being excavated from, what the likely pairing relationships are among the lunar meteorite samples, and how the lunar meteorites can help to constrain the impactor flux in the inner solar system. There will be a discussion of the biases inherent to the lunar meteorite sample suite in terms of underrepresented lithologies or regions of the Moon, and an examination of the contamination and limitations of lunar meteorites due to terrestrial weathering. The

  6. Lunar Quest in Second Life, Lunar Exploration Island, Phase II

    Science.gov (United States)

    Ireton, F. M.; Day, B. H.; Mitchell, B.; Hsu, B. C.

    2010-12-01

    Linden Lab’s Second Life is a virtual 3D metaverse created by users. At any one time there may be 40,000-50,000 users on line. Users develop a persona and are seen on screen as a human figure or avatar. Avatars move through Second Life by walking, flying, or teleporting. Users form communities or groups of mutual interest such as music, computer graphics, and education. These groups communicate via e-mail, voice, and text within Second Life. Information on downloading the Second Life browser and joining can be found on the Second Life website: www.secondlife.com. This poster details Phase II in the development of Lunar Exploration Island (LEI) located in Second Life. Phase I LEI highlighted NASA’s LRO/LCROSS mission. Avatars enter LEI via teleportation arriving at a hall of flight housing interactive exhibits on the LRO/ LCROSS missions including full size models of the two spacecraft and launch vehicle. Storyboards with information about the missions interpret the exhibits while links to external websites provide further information on the mission, both spacecraft’s instrument suites, and related EPO. Other lunar related activities such as My Moon and NLSI EPO programs. A special exhibit was designed for International Observe the Moon Night activities with links to websites for further information. The sim includes several sites for meetings, a conference stage to host talks, and a screen for viewing NASATV coverage of mission and other televised events. In Phase II exhibits are updated to reflect on-going lunar exploration highlights, discoveries, and future missions. A new section of LEI has been developed to showcase NASA’s Lunar Quest program. A new exhibit hall with Lunar Quest information has been designed and is being populated with Lunar Quest information, spacecraft models (LADEE is in place) and kiosks. A two stage interactive demonstration illustrates lunar phases with static and 3-D stations. As NASA’s Lunar Quest program matures further

  7. Covariant w∞ gravity

    NARCIS (Netherlands)

    Bergshoeff, E.; Pope, C.N.; Stelle, K.S.

    1990-01-01

    We discuss the notion of higher-spin covariance in w∞ gravity. We show how a recently proposed covariant w∞ gravity action can be obtained from non-chiral w∞ gravity by making field redefinitions that introduce new gauge-field components with corresponding new gauge transformations.

  8. Sodium Atoms in the Lunar Exotail: Observed Velocity and Spatial Distributions

    Science.gov (United States)

    Line, Michael R.; Mierkiewicz, E. J.; Oliversen, R. J.; Wilson, J. K.; Haffner, L. M.; Roesler, F. L.

    2011-01-01

    The lunar sodium tail extends long distances due to radiation pressure on sodium atoms in the lunar exosphere. Our earlier observations determined the average radial velocity of sodium atoms moving down the lunar tail beyond Earth along the Sun-Moon-Earth line (i.e., the anti-lunar point) to be 12.4 km/s. Here we use the Wisconsin H-alpha Mapper to obtain the first kinematically resolved maps of the intensity and velocity distribution of this emission over a 15 x times 15 deg region on the sky near the anti-lunar point. We present both spatially and spectrally resolved observations obtained over four nights around new moon in October 2007. The spatial distribution of the sodium atoms is elongated along the ecliptic with the location of the peak intensity drifting 3 degrees east along the ecliptic per night. Preliminary modeling results suggest that the spatial and velocity distributions in the sodium exotail are sensitive to the near surface lunar sodium velocity distribution and that observations of this sort along with detailed modeling offer new opportunities to describe the time history of lunar surface sputtering over several days.

  9. Gravity Recovery and Interior Laboratory (GRAIL): Extended Mission and End-Game Status

    Science.gov (United States)

    Zuber, Maria T.; Smith, David E.; Wieczorek, Mark A.; Williams, James G.; Andrews-Hanna, Jeffrey C.; Head, James W.; Kiefer, Walter S.; Matsuyama, Isamu; McGovern, Patrick J.; Nimmo, Francis; Stubbs, Christopher; Weber, Renee; Asmar, Sami W.; Goossens, Sander J.; Kruizinga, Gerhard; Mazarico, Erwan; Park, Ryan S.; Yuan, Dah-Ning; Konopliv, Alexander S.; Lemoine, Frank G.; Melosh, H. Jay; Neumann, Gregory A.; Phillips, Roger J.; Solomon, Sean C.; Watkins, Michael M.

    2013-01-01

    The Gravity Recovery and Interior Laboratory (GRAIL) [1], NASA s eleventh Discovery mission, successfully executed its Primary Mission (PM) in lunar orbit between March 1, 2012 and May 29, 2012. GRAIL s Extended Mission (XM) initiated on August 30, 2012 and was successfully completed on December 14, 2012. The XM provided an additional three months of gravity mapping at half the altitude (23 km) of the PM (55 km), and is providing higherresolution gravity models that are being used to map the upper crust of the Moon in unprecedented detail.

  10. Dust Mitigation for the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The lunar surface is, to a large extent, covered with a dust layer several meters thick. Known as lunar regolith, it has been produced by meteorite impacts since the...

  11. Lunar Surface Solar Electric Power System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a concentrated photovoltaic electric power system for lunar operations called C-Lite Lunar. The novel technology produces a near-term solar array system...

  12. Lunar Rover Drivetrain Development to TRL-6

    Science.gov (United States)

    Visscher, P.; Edmundson, P.; Ghafoor, N.; Jones, H.; Kleinhenz, J.; Picard, M.

    2015-10-01

    The LRPDP and SPRP rovers are designed to provide high mobility and robustness in a lunar working environment and are compatible with various lunar surface activities. TRL-6 testing is scheduled for late 2015 on the rover drivetrain components.

  13. Dust Mitigation for the Lunar Surface Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The lunar surface is to a large extent covered with a dust layer several meters thick. Known as lunar regolith, it poses a hazard in the form of dust clouds being...

  14. Constaints on Lorentz symmetry violations using lunar laser ranging observations

    Science.gov (United States)

    Bourgoin, Adrien

    2016-12-01

    General Relativity (GR) and the standard model of particle physics provide a comprehensive description of the four interactions of nature. A quantum gravity theory is expected to merge these two pillars of modern physics. From unification theories, such a combination would lead to a breaking of fundamental symmetry appearing in both GR and the standard model of particle physics as the Lorentz symmetry. Lorentz symmetry violations in all fields of physics can be parametrized by an effective field theory framework called the standard-model extension (SME). Local Lorentz Invariance violations in the gravitational sector should impact the orbital motion of bodies inside the solar system, such as the Moon. Thus, the accurate lunar laser ranging (LLR) data can be analyzed in order to study precisely the lunar motion to look for irregularities. For this purpose, ELPN (Ephéméride Lunaire Parisienne Numérique), a new lunar ephemeris has been integrated in the SME framework. This new numerical solution of the lunar motion provides time series dated in temps dynamique barycentrique (TDB). Among that series, we mention the barycentric position and velocity of the Earth-Moon vector, the lunar libration angles, the time scale difference between the terrestrial time and TDB and partial derivatives integrated from variational equations. ELPN predictions have been used to analyzed LLR observations. In the GR framework, the residuals standard deviations has turned out to be the same order of magnitude compare to those of INPOP13b and DE430 ephemerides. In the framework of the minimal SME, LLR data analysis provided constraints on local Lorentz invariance violations. Spetial attention was paid to analyze uncertainties to provide the most realistic constraints. Therefore, in a first place, linear combinations of SME coefficients have been derived and fitted to LLR observations. In a second time, realistic uncertainties have been determined with a resampling method. LLR data

  15. A massive graviton in topologically new massive gravity

    CERN Document Server

    Kim, Yong-Wan; Park, Young-Jai

    2013-01-01

    We investigate the topologically new massive gravity in three dimensions. It turns out that a single massive mode is propagating in the flat spacetime, comparing to the conformal Chern-Simons gravity which has no physically propagating degrees of freedom. Also we discuss the realization of the BMS/GCA correspondence.

  16. Sensitivity of Lunar Resource Economic Model to Lunar Ice Concentration

    Science.gov (United States)

    Blair, Brad; Diaz, Javier

    2002-01-01

    Lunar Prospector mission data indicates sufficient concentration of hydrogen (presumed to be in the form of water ice) to form the basis for lunar in-situ mining activities to provide a source of propellant for near-Earth and solar system transport missions. A model being developed by JPL, Colorado School of Mines, and CSP, Inc. generates the necessary conditions under which a commercial enterprise could earn a sufficient rate of return to develop and operate a LEO propellant service for government and commercial customers. A combination of Lunar-derived propellants, L-1 staging, and orbital fuel depots could make commercial LEO/GEO development, inter-planetary missions and the human exploration and development of space more energy, cost, and mass efficient.

  17. Lunar Flashlight: Mapping Lunar Surface Volatiles Using a Cubesat

    Science.gov (United States)

    Cohen, B. A.; Hayne, P. O.; Banazadeh, P.; Baker, J. D.; Staehle, R. L.; Paine, C..; Paige, D. A.

    2014-01-01

    Water ice and other volatiles may be located in the Moon's polar regions, with sufficient quantities for in situ extraction and utilization by future human and robotic missions. Evidence from orbiting spacecraft and the LCROSS impactor suggests the presence of surface and/or nearsurface volatiles, including water ice. These deposits are of interest to human exploration to understand their potential for use by astronauts. Understanding the composition, quantity, distribution, and form of water/H species and other volatiles associated with lunar cold traps is identified as a NASA Strategic Knowledge Gap (SKG) for Human Exploration. These polar volatile deposits could also reveal important information about the delivery of water to the Earth- Moon system, so are of scientific interest. The scientific exploration of the lunar polar regions was one of the key recommendations of the Planetary Science Decadal Survey. In order to address NASA's SKGs, the Advanced Exploration Systems (AES) program selected three lowcost 6-U CubeSat missions for launch as secondary payloads on the first test flight (EM1) of the Space Launch System (SLS) scheduled for 2017. The Lunar Flashlight mission was selected as one of these missions, specifically to address the SKG associated with lunar volatiles. Development of the Lunar Flashlight CubeSat concept leverages JPL's Interplanetary Nano- Spacecraft Pathfinder In Relevant Environment (INSPIRE) mission, MSFC's intimate knowledge of the Space Launch System and EM-1 mission, small business development of solar sail and electric propulsion hardware, and JPL experience with specialized miniature sensors. The goal of Lunar Flashlight is to determine the presence or absence of exposed water ice and its physical state, and map its concentration at the kilometer scale within the permanently shadowed regions of the lunar south pole. After being ejected in cislunar space by SLS, Lunar Flashlight deploys its solar panels and solar sail and maneuvers

  18. There's gold in them thar' lunar highlands

    Science.gov (United States)

    Stephenson, David G.

    Lunar exploration intended to find lunar resources and future sources of terrestrial electrical power is addressed focusing on economic possibilities, lunar minerals, and estimated production of precious metals. It is noted that mining the moon for He-3 will be a massive undertaking, and if it ever takes place, every effort will have to be made to extract valuable materials from the very large throughput of lunar soil.

  19. Lunar base construction requirements

    Science.gov (United States)

    Jolly, Steve; Helleckson, Brent

    1990-01-01

    The following viewgraph presentation is a review of the Lunar Base Constructibility Study carried out in the spring and summer of 1990. The objective of the study was to develop a method for evaluating the constructibility of Phase A proposals to build facilities on orbit or on extraterrestrial surfaces. Space construction was broadly defined as all forms of assembly, disassembly, connection, disconnection, deployment, stowage, excavation, emplacement, activation, test, transportation, etc., required to create facilities in orbit and on the surfaces of other celestial bodies. It was discovered that decisions made in the face of stated and unstated assumptions early in the design process (commonly called Phase A) can lock in non-optimal construction methods. Often, in order to construct the design, alterations must be made to the design during much later phases of the project. Such 'fixes' can be very difficult, expensive, or perhaps impossible. Assessing constructibility should thus be a part of the iterative design process, starting with the Phase A studies and continuing through production. This study assumes that there exists a minimum set of key construction requirements (i.e., questions whose answers form the set of discriminators) that must be implied or specified in order to assess the constructibility of the design. This set of construction requirements constitutes a 'constructibility filter' which then becomes part of the iterative design process. Five inherently different, dichotomous design reference missions were used in the extraction of these requirements to assure the depth and breath of the list.

  20. Hf, Zr, and REE partition coefficients between ilmenite and liquid - Implications for lunar petrogenesis

    Science.gov (United States)

    Nakamura, Y.; Fujimaki, H.; Nakamura, N.; Tatsumoto, M.; Mckay, G. A.

    1986-01-01

    Partition coefficients (D) between ilmenite and coexisting liquid were determined under near-lunar conditions for Hf, Zr, and REE. Through isotope dilution analysis, ilmenite D values of 0.41 and 0.33 were obtained for Hf and Zr respectively, values significantly lower than those of ilmenite from a kimberlite megacryst. Partition coefficients of REE for the synthesized ilmenite are slightly smaller than those of ilmenite from the kimberlite megacryst, and the lunar (Lu) partition coefficient is 0.056. These results suggest that ilmenite was significant in the lunar-Hf evolution of lunar mare basalts. Using lunar and Hf D values for ilmenite, the Lu-Hf evolution of lunar cumulates and the coexisting magma was examined for various crystallization sequences. The Lu-Hf variation trend of most high-Ti mare basalts is explained by a small degree of partial cumulate melting, though a higher degree is required to explain the variation of very low-Ti basalts, green glass, and Apollo 12 low-Ti basalts. Apollo 15 low-Ti basalts may require chromite crystallization as well.

  1. Signature change in loop quantum gravity: General midisuperspace models and dilaton gravity

    CERN Document Server

    Bojowald, Martin

    2016-01-01

    Models of loop quantum gravity based on real connections have a deformed notion of general covariance, which leads to the phenomenon of signature change. This result is confirmed here in a general analysis of all midisuperspace models without local degrees of freedom. As a subclass of models, 2-dimensional theories of dilaton gravity appear, but a larger set of examples is possible based only on the condition of anomaly freedom. While the classical dilaton gravity models are the only such systems without deformed covariance, they do give rise to signature change when holonomy modifications are included.

  2. Lunar Dust Contamination Effects on Lunar Base Thermal Control Systems

    Science.gov (United States)

    Keller, John R.; Ewert, Michael K.

    2000-01-01

    Many studies have been conducted to develop a thermal control system that can operate under the extreme thermal environments found on the lunar surface. While these proposed heat rejection systems use different methods to reject heat, each system contains a similar component, a thermal radiator system. These studies have always considered pristine thermal control system components and have overlooked the possible deleterious effects of lunar dust contamination. Since lunar dust has a high emissivity and absorptivity (greater than 0.9) and is opaque, dust accumulation on a surface should radically alter its optical properties and therefore alter its thermal response compared to ideal conditions. In addition, the non-specular nature of the dust particles will alter the performance of systems that employ specular surfaces to enhance heat rejection. To date, few studies have examined the effect of dust deposition on the normal control system components. These studies only focused on a single heat rejection or photovoltaic system. These studies did show that lunar dust accumulations alter the optical properties of any lunar base hardware, which in turn affects component temperatures, and heat rejection. Therefore, a new study was conducted to determine the effect of lunar dust contamination on heat rejection systems. For this study, a previously developed dust deposition model was incorporated into the Thermal Synthesizer System (TSS) model. This modeling scheme incorporates the original method of predicting dust accumulation due to vehicle landings by assuming that the thin dust layer can be treated as a semitransparent surface slightly above and in thermal contact with the pristine surface. The results of this study showed that even small amounts of dust deposits can radically alter the performance of the heat rejection systems. Furthermore. this study indicates that heat rejection systems be either located far from any landing sites or be protected from dust

  3. Looking forward to the present. [abiogenesis theory illuminated by lunar amino acids

    Science.gov (United States)

    Fox, S. W.

    1975-01-01

    The present understanding of the origin of life based on Oparin's (1924) conception of life as a manifestation of matter in a special stage of its development is outlined. The results of chemical analyses of lunar samples are discussed, and their implications regarding chemical reactions beginning with carbonaceous dust are considered. Amino acids isolated from lunar samples taken from different sites show a high degree of similarity, in agreement with the hypothesis that carbon compounds, including amino acid precursors, were implanted on the lunar surface by components of the solar wind. The amino acid precursors are most likely a cyanide compound. Overlapping amino acid/carbon ratios from lunar samples and samples of meteorites suggest a common cosmochemical state of carbon in the solar system.

  4. Dynamic model building and simulation for mechanical main body of lunar lander

    Institute of Scientific and Technical Information of China (English)

    WANG Shao-chun; DENG Zong-quan; HU Ming; GAO Hai-bo

    2005-01-01

    Focused on the dynamics problems of a lunar lander during landing process, the whole process was analysed in detail, and the linear elastic model of the moon soil was established by means of experiments-analogic method. Combining the way of elastic impact with the way of velocity replacement, the dynamics model of damping free vibration dynamics model with 3-degree of freedom(DOF) for lunar lander is obtained according to the vibration mechanics elementary theory. Based on Lagrange equations and the energy principle, the damping free vibration differential equations for the lunar lander with 3-DOF are derived and the equations are solved in simulation ways by means of ADAMS software. The conclusions obtained can be used for the design and manufacture of lunar lander.

  5. Unit operations for gas-liquid mass transfer in reduced gravity environments

    Science.gov (United States)

    Pettit, Donald R.; Allen, David T.

    1992-01-01

    Basic scaling rules are derived for converting Earth-based designs of mass transfer equipment into designs for a reduced gravity environment. Three types of gas-liquid mass transfer operations are considered: bubble columns, spray towers, and packed columns. Application of the scaling rules reveals that the height of a bubble column in lunar- and Mars-based operations would be lower than terrestrial designs by factors of 0.64 and 0.79 respectively. The reduced gravity columns would have greater cross-sectional areas, however, by factors of 2.4 and 1.6 for lunar and Martian settings. Similar results were obtained for spray towers. In contract, packed column height was found to be nearly independent of gravity.

  6. Basic radio interferometry for future lunar missions

    NARCIS (Netherlands)

    Aminaei, Amin; Klein Wolt, Marc; Chen, Linjie; Bronzwaer, Thomas; Pourshaghaghi, Hamid Reza; Bentum, Mark J.; Falcke, Heino

    2014-01-01

    In light of presently considered lunar missions, we investigate the feasibility of the basic radio interferometry (RIF) for lunar missions. We discuss the deployment of two-element radio interferometer on the Moon surface. With the first antenna element is envisaged to be placed on the lunar lander,

  7. Quantization of Emergent Gravity

    CERN Document Server

    Yang, Hyun Seok

    2013-01-01

    Emergent gravity is based on a novel form of the equivalence principle known as the Darboux theorem or the Moser lemma in symplectic geometry stating that the electromagnetic force can always be eliminated by a local coordinate transformation as far as spacetime admits a symplectic structure, in other words, a microscopic spacetime becomes noncommutative (NC). If gravity emerges from U(1) gauge theory on NC spacetime, this picture of emergent gravity suggests a completely new quantization scheme where quantum gravity is defined by quantizing spacetime itself, leading to a dynamical NC spacetime. Therefore the quantization of emergent gravity is radically different from the conventional approach trying to quantize a phase space of metric fields. This approach for quantum gravity allows a background independent formulation where spacetime as well as matter fields is equally emergent from a universal vacuum of quantum gravity.

  8. Quantization of emergent gravity

    Science.gov (United States)

    Yang, Hyun Seok

    2015-02-01

    Emergent gravity is based on a novel form of the equivalence principle known as the Darboux theorem or the Moser lemma in symplectic geometry stating that the electromagnetic force can always be eliminated by a local coordinate transformation as far as space-time admits a symplectic structure, in other words, a microscopic space-time becomes noncommutative (NC). If gravity emerges from U(1) gauge theory on NC space-time, this picture of emergent gravity suggests a completely new quantization scheme where quantum gravity is defined by quantizing space-time itself, leading to a dynamical NC space-time. Therefore the quantization of emergent gravity is radically different from the conventional approach trying to quantize a phase space of metric fields. This approach for quantum gravity allows a background-independent formulation where space-time and matter fields are equally emergent from a universal vacuum of quantum gravity.

  9. Distillation Designs for the Lunar Surface

    Science.gov (United States)

    Boul, Peter J.; Lange,Kevin E.; Conger, Bruce; Anderson, Molly

    2010-01-01

    Gravity-based distillation methods may be applied to the purification of wastewater on the lunar base. These solutions to water processing are robust physical separation techniques, which may be more advantageous than many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams.

  10. A Hamiltonian Formulation of Topological Gravity

    CERN Document Server

    Waelbroeck, Henri

    2009-01-01

    Topological gravity is the reduction of Einstein's theory to spacetimes with vanishing curvature, but with global degrees of freedom related to the topology of the universe. We present an exact Hamiltonian lattice theory for topological gravity, which admits translations of the lattice sites as a gauge symmetry. There are additional symmetries, not present in Einstein's theory, which kill the local degrees of freedom. We show that these symmetries can be fixed by choosing a gauge where the torsion is equal to zero. In this gauge, the theory describes flat space-times. We propose two methods to advance towards the holy grail of lattice gravity: A Hamiltonian lattice theory for curved space-times, with first-class translation constraints.

  11. Lunar and Planetary Science XXXVI, Part 18

    Science.gov (United States)

    2005-01-01

    Topics discussed include: PoDS: A Powder Delivery System for Mars In-Situ Organic, Mineralogic and Isotopic Analysis Instruments Planetary Differentiation of Accreting Planetesimals with 26Al and 60Fe as the Heat Sources Ground-based Observation of Lunar Surface by Lunar VIS/NIR Spectral Imager Mt. Oikeyama Structure: First Impact Structure in Japan? Central Mounds in Martian Impact Craters: Assessment as Possible Perennial Permafrost Mounds (Pingos) A Further Analysis of Potential Photosynthetic Life on Mars New Insight into Valleys-Ocean Boundary on Mars Using 128 Pixels per Degree MOLA Data: Implication for Martian Ocean and Global Climate Change; Recursive Topography Based Surface Age Computations for Mars: New Insight into Surficial Processes That Influenced Craters Distribution as a Step Toward the Formal Proof of Martian Ocean Recession, Timing and Probability; Laser-induced Breakdown Spectroscopy: A New Method for Stand-Off Quantitative Analysis of Samples on Mars; Milk Spring Channels Provide Further Evidence of Oceanic, >1.7-km-Deep Late Devonian Alamo Crater, Southern Nevada; Exploration of Martian Polar Residual Caps from HEND/ODYSSEY Data; Outflow Channels Influencing Martian Climate: Global Circulation Model Simulations with Emplaced Water; Presence of Nonmethane Hydrocarbons on Pluto; Difference in Degree of Space Weathering on the Newborn Asteroid Karin; Circular Collapsed Features Related to the Chaotic Terrain Formation on Mars; A Search for Live (sup 244)Pu in Deep-Sea Sediments: Preliminary Results of Method Development; Some Peculiarities of Quartz, Biotite and Garnet Transformation in Conditions of Step-like Shock Compression of Crystal Slate; Error Analysis of Remotely-Acquired Mossbauer Spectra; Cloud Activity on Titan During the Cassini Mission; Solar Radiation Pressure and Transient Flows on Asteroid Surfaces; Landing Site Characteristics for Europa 1: Topography; and The Crop Circles of Europa.

  12. Plant biology in reduced gravity on the Moon and Mars.

    Science.gov (United States)

    Kiss, J Z

    2014-01-01

    While there have been numerous studies on the effects of microgravity on plant biology since the beginning of the Space Age, our knowledge of the effects of reduced gravity (less than the Earth nominal 1 g) on plant physiology and development is very limited. Since international space agencies have cited manned exploration of Moon/Mars as long-term goals, it is important to understand plant biology at the lunar (0.17 g) and Martian levels of gravity (0.38 g), as plants are likely to be part of bioregenerative life-support systems on these missions. First, the methods to obtain microgravity and reduced gravity such as drop towers, parabolic flights, sounding rockets and orbiting spacecraft are reviewed. Studies on gravitaxis and gravitropism in algae have suggested that the threshold level of gravity sensing is around 0.3 g or less. Recent experiments on the International Space Station (ISS) showed attenuation of phototropism in higher plants occurs at levels ranging from 0.l g to 0.3 g. Taken together, these studies suggest that the reduced gravity level on Mars of 0.38 g may be enough so that the gravity level per se would not be a major problem for plant development. Studies that have directly considered the impact of reduced gravity and microgravity on bioregenerative life-support systems have identified important biophysical changes in the reduced gravity environments that impact the design of these systems. The author suggests that the current ISS laboratory facilities with on-board centrifuges should be used as a test bed in which to explore the effects of reduced gravity on plant biology, including those factors that are directly related to developing life-support systems necessary for Moon and Mars exploration.

  13. International Collaboration in Lunar Exploration

    Science.gov (United States)

    Morris, K. Bruce; Horack, John M.; Nall, Mark; Leahy, Bart. D.

    2007-01-01

    The U.S. Vision for Space Exploration commits the United States to return astronauts to the moon by 2020 using the Ares I Crew Launch Vehicle and Ares V Cargo Launch Vehicle. Like the Apollo program of the 1960s and 1970s, this effort will require preliminary reconnaissance in the form of robotic landers and probes. Unlike Apollo, some of the data NASA will rely upon to select landing sites and conduct science will be based on international missions as well, including SMART-1, SELENE, and Lunar Reconnaissance Orbiter (LRO). Opportunities for international cooperation on the moon also lie in developing lunar exploration technologies. The European Space Agency's SMART-1 orbiter (Figure 1) is making the first comprehensive inventory of key chemical elements in the lunar surface. It is also investigating the impact theory of the moon's formation.'

  14. Lunar Ice Cube: Searching for Lunar Volatiles with a lunar cubesat orbiter

    Science.gov (United States)

    Clark, Pamela E.; Malphrus, Ben; Brown, Kevin; Hurford, Terry; Brambora, Cliff; MacDowall, Robert; Folta, David; Tsay, Michael; Brandon, Carl; Lunar Ice Cube Team

    2016-10-01

    Lunar Ice Cube, a NASA HEOMD NextSTEP science requirements-driven deep space exploration 6U cubesat, will be deployed, with 12 others, by NASA's EM1 mission. The mission's high priority science application is understanding volatile origin, distribution, and ongoing processes in the inner solar system. JPL's Lunar Flashlight, and Arizona State University's LunaH-Map, also lunar orbiters to be deployed by EM1, will provide complementary observations. Lunar Ice Cube utilizes a versatile GSFC-developed payload: BIRCHES, Broadband InfraRed Compact, High-resolution Exploration Spectrometer, a miniaturized version of OVIRS on OSIRIS-REx. BIRCHES is a compact (1.5U, 2 kg, 20 W including cryocooler) point spectrometer with a compact cryocooled HgCdTe focal plane array for broadband (1 to 4 micron) measurements and Linear Variable Filter enabling 10 nm spectral resolution. The instrument will achieve sufficient SNR to identify water in various forms, mineral bands, and potentially other volatiles seen by LCROSS (e.g., CH4) as well. GSFC is developing compact instrument electronics easily configurable for H1RG family of focal plane arrays. The Lunar Ice Cube team is led by Morehead State University, who will provide build, integrate and test the spacecraft and provide mission operations. Onboard communication will be provided by the X-band JPL Iris Radio and dual X-band patch antennas. Ground communication will be provided by the DSN X-band network, particularly the Morehead State University 21-meter substation. Flight Dynamics support is provided by GSFC. The Busek micropropulsion system in a low energy trajectory will allow the spacecraft to achieve the science orbit less than a year. The high inclination, equatorial periapsis orbit will allow coverage of overlapping swaths once every lunar cycle at up to six different times of day (from dawn to dusk) as the mission progresses during its nominal six month science mapping period. Led by the JPL Science PI, the Lunar Ice Cube

  15. Lunar Base Heat Pump

    Science.gov (United States)

    Walker, D.; Fischbach, D.; Tetreault, R.

    1996-01-01

    The objective of this project was to investigate the feasibility of constructing a heat pump suitable for use as a heat rejection device in applications such as a lunar base. In this situation, direct heat rejection through the use of radiators is not possible at a temperature suitable for lde support systems. Initial analysis of a heat pump of this type called for a temperature lift of approximately 378 deg. K, which is considerably higher than is commonly called for in HVAC and refrigeration applications where heat pumps are most often employed. Also because of the variation of the rejection temperature (from 100 to 381 deg. K), extreme flexibility in the configuration and operation of the heat pump is required. A three-stage compression cycle using a refrigerant such as CFC-11 or HCFC-123 was formulated with operation possible with one, two or three stages of compression. Also, to meet the redundancy requirements, compression was divided up over multiple compressors in each stage. A control scheme was devised that allowed these multiple compressors to be operated as required so that the heat pump could perform with variable heat loads and rejection conditions. A prototype heat pump was designed and constructed to investigate the key elements of the high-lift heat pump concept. Control software was written and implemented in the prototype to allow fully automatic operation. The heat pump was capable of operation over a wide range of rejection temperatures and cooling loads, while maintaining cooling water temperature well within the required specification of 40 deg. C +/- 1.7 deg. C. This performance was verified through testing.

  16. Black Hole Interior in Quantum Gravity.

    Science.gov (United States)

    Nomura, Yasunori; Sanches, Fabio; Weinberg, Sean J

    2015-05-22

    We discuss the interior of a black hole in quantum gravity, in which black holes form and evaporate unitarily. The interior spacetime appears in the sense of complementarity because of special features revealed by the microscopic degrees of freedom when viewed from a semiclassical standpoint. The relation between quantum mechanics and the equivalence principle is subtle, but they are still consistent.

  17. Viability of nonminimally coupled f (R) gravity

    Science.gov (United States)

    Bertolami, Orfeu; Páramos, Jorge

    2016-03-01

    In this work we explore the viability of nonminimally coupled matter-curvature gravity theories, namely the conditions required for the absence of tachyon instabilities and ghost degrees of freedom. We contrast our finds with recent claims of a pathological behaviour of this class of models, which resorted to, in our view, an incorrect analogy with k-essence.

  18. NASA's Lunar Robotic Architecture Study

    Science.gov (United States)

    Mulville, Daniel R.

    2006-07-01

    This report documents the findings and analysis of a 60-day agency-wide Lunar Robotic Architecture Study (LRAS) conducted by the National Aeronautics and Space Administration (NASA). Work on this study began in January 2006. Its purpose was to: Define a lunar robotics architecture by addressing the following issues: 1) Do we need robotic missions at all? If so, why and under what conditions? 2) How would they be accomplished and at what cost? Are they within budget? 3) What are the minimum requirements? What is the minimum mission set? 4) Integrate these elements together to show a viable robotic architecture. 5) Establish a strategic framework for a lunar robotics program. The LRAS Final Report presents analysis and recommendations concerning potential approaches related to NASA s implementation of the President's Vision for Space Exploration. Project and contract requirements will likely be derived in part from the LRAS analysis and recommendations contained herein, but these do not represent a set of project or contract requirements and are not binding on the U.S. Government unless and until they are formally and expressly adopted as such. Details of any recommendations offered by the LRAS Final Report will be translated into implementation requirements. Moreover, the report represents the assessments and projects of the report s authors at the time it was prepared; it is anticipated that the concepts in this report will be analyzed further and refined. By the time some of the activities addressed in this report are implemented, certain assumptions on which the report s conclusions are based will likely evolve as a result of this analysis. Accordingly, NASA, and any entity under contract with NASA, should not use the information in this report for final project direction. Since the conclusion of this study, there have been various changes to the Agency's current portfolio of lunar robotic precursor activities. First, the Robotic Lunar Exploration Program (RLEP

  19. Lunar Prospecting With Chandra

    Science.gov (United States)

    2003-09-01

    Observations of the bright side of the Moon with NASA's Chandra X-ray Observatory have detected oxygen, magnesium, aluminum and silicon over a large area of the lunar surface. The abundance and distribution of those elements will help to determine how the Moon was formed. "We see X-rays from these elements directly, independent of assumptions about the mineralogy and other complications," said Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., at a press conference at the "Four Years with Chandra" symposium in Huntsville, Alabama. "We have Moon samples from the six widely-space Apollo landing sites, but remote sensing with Chandra can cover a much wider area," continued Drake. "It's the next best thing to being there, and it's very fast and cost-effective." The lunar X-rays are caused by fluorescence, a process similar to the way that light is produced in fluorescent lamps. Solar X-rays bombard the surface of the Moon, knock electrons out of the inner parts of the atoms, putting them in a highly unstable state. Almost immediately, other electrons rush to fill the gaps, and in the process convert their energy into the fluorescent X-rays seen by Chandra. According to the currently popular "giant impact" theory for the formation of the Moon, a body about the size of Mars collided with the Earth about 4.5 billion years ago. This impact flung molten debris from the mantle of both the Earth and the impactor into orbit around the Earth. Over the course of tens of millions of years, the debris stuck together to form the Moon. By measuring the amounts of aluminum and other elements over a wide area of the Moon and comparing them to the Earth's mantle, Drake and his colleagues plan to help test the giant impact hypothesis. "One early result," quipped Drake, "is that there is no evidence for large amounts of calcium, so cheese is not a major constituent of the Moon." Illustration of Earth's Geocorona Illustration of Earth's Geocorona The same

  20. On the non-uniqueness of local quasi-geoids computed from terrestrial gravity anomalies

    NARCIS (Netherlands)

    Prutkin, I.; Klees, R.

    2007-01-01

    We consider the problem of local (quasi-)geoid modelling from terrestrial gravity anomalies. Whereas this problem is uniquely solvable (up to spherical harmonic degree one) if gravity anomalies are globally available, the problem is non-unique if gravity anomalies are only available within a local a

  1. On the non-uniqueness of local quasi-geoids computed from terrestrial gravity anomalies

    NARCIS (Netherlands)

    Prutkin, I.; Klees, R.

    2007-01-01

    We consider the problem of local (quasi-)geoid modelling from terrestrial gravity anomalies. Whereas this problem is uniquely solvable (up to spherical harmonic degree one) if gravity anomalies are globally available, the problem is non-unique if gravity anomalies are only available within a local

  2. Manufacturing High-Fidelity Lunar Agglutinate Simulants

    Science.gov (United States)

    Gutafson, R. J.; Edmunson, J. E.; Rickman, D. L.

    2010-01-01

    The lunar regolith is very different from many naturally occurring material on Earth because it forms in the unique, impact-dominated environment of the lunar surface. Lunar regolith is composed of five basic particle types: mineral fragments, pristine crystalline rock fragments, breccia fragments, glasses of various kinds, and agglutinates (glass-bonded aggregates). Agglutinates are abundant in the lunar regolith, especially in mature regoliths where they can be the dominant component.This presentation will discuss the technical feasibility of manufacturing-simulated agglutinate particles that match many of the unique properties of lunar agglutinates.

  3. Economic geology of lunar Helium-3

    Science.gov (United States)

    Schmitt, Harrison H.

    1988-09-01

    Economic geology evaluation of lunar He-3 should answer the question: Can lunar He-3 be sold on Earth with sufficient profit margins and low enough risk to attract capital investment in the enterprise. Concepts that relate to economic geology of recovering He-3 from the lunar maria are not new to human experience. A parametric cost and technology evaluation scheme, based on existing and future data, is required to qualitatively and quantitatively assess the comprehensive economic feasibility and return on investment of He-3 recovery from the lunar maria. There are also many political issues which must be considered as a result of nuclear fusion and lunar mining.

  4. What is a lunar standstill III?

    Directory of Open Access Journals (Sweden)

    Lionel Duke Sims

    2016-12-01

    Full Text Available Prehistoric monument alignments on lunar standstills are currently understood for horizon range, perturbation event, crossover event, eclipse prediction, solstice full Moon and the solarisation of the dark Moon. The first five models are found to fail the criteria of archaeoastronomy field methods. The final model of lunar-solar conflation draws upon all the observed components of lunar standstills – solarised reverse phased sidereal Moons culminating in solstice dark Moons in a roughly nine-year alternating cycle between major and minor standstills. This lunar-solar conflation model is a syncretic overlay upon an antecedent Palaeolithic template for lunar scheduled rituals and amenable to transformation.

  5. Geopolymers from lunar and Martian soil simulants

    Science.gov (United States)

    Alexiadis, Alessio; Alberini, Federico; Meyer, Marit E.

    2017-01-01

    This work discusses the geopolymerization of lunar dust simulant JSC LUNAR-1A and Martian dust simulant JSC MARS-1A. The geopolymerization of JSC LUNAR-1A occurs easily and produces a hard, rock-like, material. The geopolymerization of JSC MARS-1A requires milling to reduce the particle size. Tests were carried out to measure, for both JSC LUNAR-1A and JSC MARS-1A geopolymers, the maximum compressive and flexural strengths. In the case of the lunar simulant, these are higher than those of conventional cements. In the case of the Martian simulant, they are close to those of common building bricks.

  6. APOLLO 14: Lift off from lunar surface

    Science.gov (United States)

    1974-01-01

    APOLLO 14: The lunar module 'Falcon' lifts off from the lunar surface From the film documentary 'APOLLO 14: 'Mission to Fra Mauro'', part of a documentary series on the APOLLO missions made in the early '70's and narrated by Burgess Meredith. APOLO 14: Third manned lunar landing with Alan B. Shepard, Jr.,Stuart A. Roosa, and Edgar D. Mitchell. Landed in the Fra Mauro area on Ferurary 5, 1971; performed EVA, deployed lunar experiments, returned lunar samples. Mission Duration 216 hrs 1 min 58 sec

  7. Economic geology of lunar Helium-3

    Science.gov (United States)

    Schmitt, Harrison H.

    1988-01-01

    Economic geology evaluation of lunar He-3 should answer the question: Can lunar He-3 be sold on Earth with sufficient profit margins and low enough risk to attract capital investment in the enterprise. Concepts that relate to economic geology of recovering He-3 from the lunar maria are not new to human experience. A parametric cost and technology evaluation scheme, based on existing and future data, is required to qualitatively and quantitatively assess the comprehensive economic feasibility and return on investment of He-3 recovery from the lunar maria. There are also many political issues which must be considered as a result of nuclear fusion and lunar mining.

  8. Investigation of the properties of icy lunar polar regolith simulants

    Science.gov (United States)

    Pitcher, Craig; Kömle, Norbert; Leibniz, Otto; Morales-Calderon, Odalys; Gao, Yang; Richter, Lutz

    2016-03-01

    As icy regolith is believed to exist in the subsurface of permanently shadowed areas near the lunar south pole, there is a growing interest in obtaining samples from these polar regions. To qualify for spaceflight, sampling instruments must demonstrate their ability to operate in the expected environment. However, there is currently no quantitative data detailing the extent and distribution of ice in polar regolith. While work has been done to determine the effects of water ice content in simulants such as JSC-1A, to date there has been no investigation into the properties of icy simulants of the regolith believed to be found at lunar polar regions. A series of experiments has therefore been conducted to determine the properties of icy NU-LHT-2M lunar highland simulant, an approximation of lunar polar regolith, at varying degrees of saturation. A number of procedures for preparing the simulant were tested, with the aim of defining a standardised technique for the creation of icy simulants with controlled water contents. Saturation of the highland simulant was found to occur at a water mass content between 13% and 17%, while cone penetration tests demonstrated that a significant increase in penetration resistance occurs at 5 ± 1%. Uniaxial compression tests showed an increase in regolith strength with water mass and density, which slows down as the saturation level is reached. The results presented here demonstrate the first characterisation of the properties of icy lunar polar regolith simulants, which can be expanded upon to further the understanding of its properties for use in future instrumentation testing.

  9. Gravity Degrees of Freedom on a Null Surface

    CERN Document Server

    Hopfmüller, Florian

    2016-01-01

    A canonical analysis for general relativity is performed on a null surface without fixing the diffeomorphism gauge, and the canonical pairs of configuration and momentum variables are derived. Next to the well-known spin-2 pair, also spin-1 and spin-0 pairs are identified. The boundary action for a null boundary segment of spacetime is obtained, including terms on codimension two corners.

  10. Impact of Infrared Lunar Laser Ranging on Lunar Dynamics

    Science.gov (United States)

    Viswanathan, Vishnu; Fienga, Agnès; Manche, Hervé; Gastineau, Mickael; Courde, Clément; Torre, Jean-Marie; Exertier, Pierre; Laskar, Jacques; LLR Observers : Astrogeo-OCA, Apache Point, McDonald Laser Ranging Station, Haleakala Observatory, Matera Laser Ranging Observatory

    2016-10-01

    Since 2015, in addition to the traditional green (532nm), infrared (1064nm) has been the preferred wavelength for lunar laser ranging at the Calern lunar laser ranging (LLR) site in France. Due to the better atmospheric transmission of IR with respect to Green, nearly 3 times the number of normal points have been obtained in IR than in Green [ C.Courde et al 2016 ]. In our study, in addition to the historical data obtained from various other LLR sites, we include the recent IR normal points obtained from Calern over the 1 year time span (2015-2016), constituting about 4.2% of data spread over 46 years of LLR. Near even distribution of data provided by IR on both the spatial and temporal domain, helps us to improve constraints on the internal structure of the Moon modeled within the planetary ephemeris : INPOP [ Fienga et al 2015 ]. IERS recommended models have been used in the data reduction software GINS (GRGS,CNES) [ V.Viswanathan et al 2015 ]. Constraints provided by GRAIL, on the Lunar gravitational potential and Love numbers have been taken into account in the least-square fit procedure. New estimates on the dynamical parameters of the lunar core will be presented.

  11. Activity in the lunar surface: Transient Lunar Phenomena

    CERN Document Server

    AF, Cruz Roa

    2013-01-01

    Transient Lunar Phenomena (TLP) observed on the surface of the moon, are of high rarity, low repetition rate and very short observation times, resulting in that there is little information about this topic. This necessitates the importance of studying them in detail. They have been observed as very bright clouds of gases of past geological lunar activity. According its duration, there have been registered in different colors (yellow, orange, red). Its size can vary from a few to hundreds of kilometers. The TLP Usually occur in certain locations as in some craters (Aristarchus, Plato, Kepler, etc.) and at the edges of lunar maria (Sea of Fecundity, Alps hills area, etc.). The exposure time of a TLP can vary from a few seconds to a little more than one hour. In this paper, a literature review of the TLP is made to build a theory from the existing reports and scientific hypotheses, trying to unify and synthesize data and concepts that are scattered by different lunar research lines. The TLP need to be explained ...

  12. Reflectance Spectral Characteristics of Lunar Surface Materials

    Institute of Scientific and Technical Information of China (English)

    Yong-Liao Zou; Jian-Zhong Liu; Jian-Jun Liu; Tao Xu

    2004-01-01

    Based on a comprehensive analysis of the mineral composition of major lunar rocks (highland anorthosite, lunar mare basalt and KREEP rock), we investigate the reflectance spectral characteristics of the lunar rock-forming minerals, including feldspar, pyroxene and olivine. The affecting factors, the variation of the intensity of solar radiation with wavelength and the reflectance spectra of the lunar rocks are studied. We also calculate the reflectivity of lunar mare basalt and highland anorthosite at 300 nm, 415 nm, 750 nm, 900 nm, 950 nm and 1000 nm.It is considered that the difference in composition between lunar mare basalt and highland anorthosite is so large that separate analyses are needed in the study of the reflectivity of lunar surface materials in the two regions covered by mare basalt and highland anorthosite, and especially in the region with high Th contents, which may be the KREEP-distributed region.

  13. Entropy and Quantum Gravity

    Directory of Open Access Journals (Sweden)

    Bernard S. Kay

    2015-12-01

    Full Text Available We give a review, in the style of an essay, of the author’s 1998 matter-gravity entanglement hypothesis which, unlike the standard approach to entropy based on coarse-graining, offers a definition for the entropy of a closed system as a real and objective quantity. We explain how this approach offers an explanation for the Second Law of Thermodynamics in general and a non-paradoxical understanding of information loss during black hole formation and evaporation in particular. It also involves a radically different from usual description of black hole equilibrium states in which the total state of a black hole in a box together with its atmosphere is a pure state—entangled in just such a way that the reduced state of the black hole and of its atmosphere are each separately approximately thermal. We also briefly recall some recent work of the author which involves a reworking of the string-theory understanding of black hole entropy consistent with this alternative description of black hole equilibrium states and point out that this is free from some unsatisfactory features of the usual string theory understanding. We also recall the author’s recent arguments based on this alternative description which suggest that the Anti de Sitter space (AdS/conformal field theory (CFT correspondence is a bijection between the boundary CFT and just the matter degrees of freedom of the bulk theory.

  14. Phases of massive gravity

    CERN Document Server

    Dubovsky, S L

    2004-01-01

    We systematically study the most general Lorentz-violating graviton mass invariant under three-dimensional Eucledian group using the explicitly covariant language. We find that at general values of mass parameters the massive graviton has six propagating degrees of freedom, and some of them are ghosts or lead to rapid classical instabilities. However, there is a number of different regions in the mass parameter space where massive gravity can be described by a consistent low-energy effective theory with cutoff $\\sim\\sqrt{mM_{Pl}}$ free of rapid instabilities and vDVZ discontinuity. Each of these regions is characterized by certain fine-tuning relations between mass parameters, generalizing the Fierz--Pauli condition. In some cases the required fine-tunings are consequences of the existence of the subgroups of the diffeomorphism group that are left unbroken by the graviton mass. We found two new cases, when the resulting theories have a property of UV insensitivity, i.e. remain well behaved after inclusion of ...

  15. Determination of Antarctic geoid by using global gravity field

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    With Chinese latest global gravity field model WDM94, the authors providethe geoid height and mean free-air gravity anomaly of Antarctica (The range of latitude is from—60° to—90°). In order to conclude and analyze the characters of Antarctic geoid roundly, the authors collect the latest oversea global gravity field model OSU91 (to degree and order 360) and JGMOSU (to degree and order 360), get the corresponding geoid height and mean free-air gravity anomaly. The results arecompared with the results got from WDM94, thus we get the difference. The standard deviation of geoid height between WDM94 and OSU91 is ± 1.90 re;the deviation of geoid between WDM9 and JGMOSU is ± 2.09 m. The standard deviation of mean gravity anomaly are±8.97 mGal and ± 9.32 mGal respectively.

  16. Intersecting Quantum Gravity with Noncommutative Geometry - a Review

    Directory of Open Access Journals (Sweden)

    Johannes Aastrup

    2012-03-01

    Full Text Available We review applications of noncommutative geometry in canonical quantum gravity. First, we show that the framework of loop quantum gravity includes natural noncommutative structures which have, hitherto, not been explored. Next, we present the construction of a spectral triple over an algebra of holonomy loops. The spectral triple, which encodes the kinematics of quantum gravity, gives rise to a natural class of semiclassical states which entail emerging fermionic degrees of freedom. In the particular semiclassical approximation where all gravitational degrees of freedom are turned off, a free fermionic quantum field theory emerges. We end the paper with an extended outlook section.

  17. Demonstrating Martian Gravity

    CERN Document Server

    Pirkola, Patrik

    2016-01-01

    The surface gravity on Mars is smaller than the surface gravity on Earth, resulting in longer falling times. This effect can be simulated on Earth by taking advantage of air resistance and buoyancy, which cause low density objects to fall slowly enough to approximate objects falling on the surface of Mars. We describe a computer simulation based on an experiment that approximates Martian gravity, and verify our numerical results by performing the experiment.

  18. Is Gravity Entropic Force?

    Directory of Open Access Journals (Sweden)

    Rongjia Yang

    2014-08-01

    Full Text Available If we assume that the source of thermodynamic system, ρ and p, are also the source of gravity, then either thermal quantities, such as entropy, temperature, and chemical potential, can induce gravitational effects, or gravity can induce thermal effects. We find that gravity can be seen as entropic force only for systems with constant temperature and zero chemical potential. The case for Newtonian approximation is discussed.

  19. Combinatorial Quantum Gravity

    CERN Document Server

    Trugenberger, Carlo A

    2016-01-01

    In a recently developed approach, geometry is modelled as an emergent property of random networks. Here I show that one of these models I proposed is exactly quantum gravity defined in terms of the combinatorial Ricci curvature recently derived by Ollivier. Geometry in the weak (classical) gravity regime arises in a phase transition driven by the condensation of short graph cycles. The strong (quantum) gravity regime corresponds to "small world" random graphs with logarithmic distance scaling.

  20. Anomalies and gravity

    CERN Document Server

    Mielke, E W

    2006-01-01

    Anomalies in Yang-Mills type gauge theories of gravity are reviewed. Particular attention is paid to the relation between the Dirac spin, the axial current j_5 and the non-covariant gauge spin C. Using diagrammatic techniques, we show that only generalizations of the U(1)- Pontrjagin four--form F^ F= dC arise in the chiral anomaly, even when coupled to gravity. Implications for Ashtekar's canonical approach to quantum gravity are discussed.

  1. Lunar science. [geophysics, mineralogy and evolution of moon

    Science.gov (United States)

    Brett, R.

    1973-01-01

    A review of the recent developments in lunar science summarizing the most important lunar findings and the known restraints on the theories of lunar evolution is presented. Lunar geophysics is discussed in sections dealing with the figure of the moon, mascons, and the lunar thermal regime; recent seismic studies and magnetic results are reported. The chemical data on materials taken from lunar orbit are analyzed, and the lunar geology is discussed. Special attention is accorded the subject of minerology, reflecting the information obtained from lunar samples of both mare and nonmare origin. A tentative timetable of lunar events is proposed, and the problem of the moon's origin is briefly treated.

  2. An improved value of the lunar moment of inertia

    Science.gov (United States)

    Blackshear, W. T.; Gapcynski, J. P.

    1977-01-01

    The lunar gravitational research reported on by Gapcynski et al., (1975) has been extended to include an additional 600 days of the time variation of ascending node for the Explorer 49 spacecraft. Analysis of these additional data resulted in an improved value of the second-degree zonal harmonic coefficient C(20) = (-2.0219 equal to 0.0091) times 10 to the minus 4. This value of C(20) used in conjunction with the parameters beta equal to libration (631.27 + or - 0.03) times 10 to the minus 6 and gamma to (227.7 + or - 0.7) times 10 to the minus 6 yields a more accurate definition of the lunar moment of inertia ratio equal to 0.391 + or - 0.002.

  3. Lunar resources and their utilization

    Science.gov (United States)

    Phinney, W. C.; Criswell, D.; Drexler, E.; Garmirian, J.

    1977-01-01

    Lunar surface materials offer a source of raw materials for space processing to produce structural metals, oxygen, silicon, glass, and ceramic products. Significant difference exist, however, between lunar surface materials in the highlands and those in the maria. In the highlands the soil depth is at least an order of magnitude greater, the Al:Fe ratio is ten times greater, the content of plagioclase as a source of clear glass is three times as great, and the content of Ti is at least an order of magnitude lower. Evaluation of the extractive metallurgy and chemical operations associated with carbothermic and silicothermic refinement of lunar regolith suggests that Fe, Al, Si, Mg and probably Ti, Cr and Mn can be recovered, while oxygen is produced as a by-product. A conservative plant design yields its own weight in oxygen, silicon, and structural metals in less than six days. Power requirements for a throughput of 300,000 tons per year is less than 500 megawatts. The processing is done more economically in space than on the lunar surface.

  4. Lunar secondary craters, part K

    Science.gov (United States)

    Overbeck, V. R.; Morrison, R. H.; Wedekind, J.

    1972-01-01

    Formation of V-shaped structures surrounding the fresh Copernicus Crater and its secondary craters are reviewed, and preliminary observations of the more extensively eroded secondary crater field of Theophilus are presented. Results of laboratory simulation of secondary lunar craters to examine their effects on V-shaped ridges are also described.

  5. Lunar articulated remote transportation system

    Science.gov (United States)

    1990-01-01

    The students of the Florida A&M/Florida State University College of Engineering continued their design from 1988 to 1989 on a first generation lunar transportation vehicle for use on the surface of the Moon between the years 2010 and 2020. Attention is focused on specific design details on all components of the Lunar Articulated Remote Transportation System (Lunar ARTS). The Lunar ARTS will be a three-cart, six-wheeled articulated vehicle. Its purpose will be the transportation of astronauts and/or materials for excavation purposes at a short distance from the base (37.5 km). The power system includes fuel cells for both the primary system and the back-up system. The vehicle has the option of being operated in a manned or unmanned mode. The unmanned mode includes stereo imaging with signal processing for navigation. For manned missions the display console is a digital readout displayed on the inside of the astronaut's helmet. A microprocessor is also on board the vehicle. Other components of the vehicle include a double wishbone/flexible hemispherical wheel suspension; chassis; a steering system; motors; seat retraints; heat rejection systems; solar flare protection; dust protection; and meteoroid protection. A one-quarter scale dynamic model has been built to study the dynamic behavior of the vehicle. The dynamic model closely captures the mechanical and electrical details of the total design.

  6. The Megalithic Lunar Season Pointer

    DEFF Research Database (Denmark)

    Clausen, Claus

    are concentrated in the east, east- southeast and southeast. This orientation points to specific full moons during the summer period – the lunar season pointer, where the rising points of the full moons, at the horizon concentrate around a few specific directions in the Southeastern quadrant, which specially...

  7. Concept of Lunar Energy Park

    Science.gov (United States)

    Niino, Masayuki; Kisara, Katsuto; Chen, Lidong

    1993-10-01

    This paper presents a new concept of energy supply system named Lunar Energy Park (LEP) as one of the next-generation clean energy sources. In this concept, electricity is generated by nuclear power plants built on the moon and then transmitted to receiving stations on the earth by laser beam through transporting systems situated in geostationary orbit. The lunar nuclear power plants use a high-efficiency composite energy conversion system consisting of thermionic and thermoelectric generators to change nuclear thermal energy into electricity directly. The nuclear resources are considered to be available from the moon, and nuclear fuel transport from earth to moon is not necessary. Because direct energy conversion systems are employed, the lunar nuclear plants can be operated and controlled by robots and are maintenance-free, and so will cause no pollution to humans. The key technologies for LEP include improvements of conversion efficiency of both thermionic and thermoelectric converters, and developments of laser-beam power transmission technology as well. The details, including the construction of lunar nuclear plants, energy conversion and energy transmission systems, as well as the research plan strategies for this concept are reviewed.

  8. Mobile Lunar Laser Ranging Station

    Science.gov (United States)

    Intellect, 1977

    1977-01-01

    Harlan Smith, chairman of the University of Texas's Astronomy Department, discusses a mobile lunar laser ranging station which could help determine the exact rates of movement between continents and help geophysicists understand earthquakes. He also discusses its application for studying fundamental concepts of cosmology and physics. (Editor/RK)

  9. Martian "microfossils" in lunar meteorites?

    Science.gov (United States)

    Sears, D W; Kral, T A

    1998-07-01

    One of the five lines of evidence used by McKay et al. (1996) for relic life in the Martian meteorite Allan Hills (ALH) 84001 was the presence of objects thought to be microfossils. These ovoid and elongated forms are similar to structures found in terrestrial rocks and described as "nanobacteria" (Folk, 1993; McBride et al., 1994). Using the same procedures and apparatus as McKay et al. (1996), we have found structures on internal fracture surfaces of lunar meteorites that cannot be distinguished from the objects described on similar surfaces in ALH 84001. The lunar surface is currently a sterile environment and probably always has been. However, the lunar and Martian meteorites share a common terrestrial history, which includes many thousands of years of exposure to Antarctic weathering. Although we do not know the origin of these ovoid and elongated forms, we suggest that their presence on lunar meteorites indicates that the objects described by McKay et al. (1996) are not of Martian biological origin.

  10. Lunar Polar Landing Sites

    Science.gov (United States)

    Kamps, Oscar; Foing, Bernard H.; Flahaut, Jessica

    2016-07-01

    An important step for a scientific mission is to assess on where the mission should be conducted. This study on landing site selection focuses on a mission to the poles of the Moon where an in-situ mission should be conducted to answer the questions with respect to volatiles and ices. The European interest for a mission to the poles of the Moon is presented in the mission concept called Heracles. This mission would be a tele-operated, sample return mission where astronauts will controlling a rover from an Orion capsule in cislunar orbit. The primary selection of landing sites was based on the scientific interest of areas near the poles. The maximum temperature map from Diviner was used to select sites where CO^2¬ should always be stable. This means that the maximum temperature is lower than 54K which is the sublimation temperature for CO^2¬ in lunar atmospheric pressure. Around these areas 14 potential regions of interest were selected. Further selection was based on the epoch of the surface in these regions of interest. It was thought that it would be of high scientific value if sites are sampled which have another epoch than already sampled by one of the Apollo or Luna missions. Only 6 sites on both North as South Pole could contain stable CO^2 ¬and were older than (Pre-)Necterian. Before a landing site and rover traverse was planned these six sites were compared on their accessibility of the areas which could contain stable CO^2. It was assumed that slope lower than 20^o is doable to rove. Eventually Amundsen and Rozhdestvenskiy West were selected as regions of interest. Assumptions for selecting landing sites was that area should have a slope lower than 5^o, a diameter of 1km, in partial illuminated area, and should not be isolated but inside an area which is in previous steps marked as accessible area to rove. By using multiple tools in ArcGIS it is possible to present the area's which were marked as potential landing sites. The closest potential landing

  11. Gravity Independent Compressor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop and demonstrate a small, gravity independent, vapor compression refrigeration system using a linear motor compressor which effectively...

  12. Classical Weyl transverse gravity

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Ichiro [University of the Ryukyus, Department of Physics, Faculty of Science, Nishihara, Okinawa (Japan)

    2017-05-15

    We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge-fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally invariant scalar tensor gravity and the WTDiff gravity is a ''fake'' symmetry. We find it possible to extend this proof to all matter fields, i.e. the Weyl-invariant scalar, vector and spinor fields. Fourthly, it is explicitly shown that in the WTDiff gravity the Schwarzschild black hole metric and a charged black hole one are classical solutions to the equations of motion only when they are expressed in the Cartesian coordinate system. Finally, we consider the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology and provide some exact solutions. (orig.)

  13. influence of gravity

    Directory of Open Access Journals (Sweden)

    Animesh Mukherjee

    1991-01-01

    Full Text Available Based upon Biot's [1965] theory of initial stresses of hydrostatic nature produced by the effect of gravity, a study is made of surface waves in higher order visco-elastic media under the influence of gravity. The equation for the wave velocity of Stonely waves in the presence of viscous and gravitational effects is obtained. This is followed by particular cases of surface waves including Rayleigh waves and Love waves in the presence of viscous and gravity effects. In all cases the wave-velocity equations are found to be in perfect agreement with the corresponding classical results when the effects of gravity and viscosity are neglected.

  14. Lunar Rings In South Africa.

    Science.gov (United States)

    Makarenko, G. F.

    Recently [1], when I have revealed the basic property of planet Earth's outer shell ­ its axial structural symmetry. Thus, it became clear that mobilistic models are void now. One can see W.Indic and E.Pacific ridges on thje same meridiane (60 E, 120 W). They stretch northward to Urals (variscan) and Cordilleras (laramian) with the edge of Bear zone (precambrian) in America. Other structures are obvious. The giant fault-ridge line Apsheron - N.Anatolia - Atlas - Mavritanians has as its twin on the other globe side the fracture zone Mendocino with the Mapmaker island chain. African Ugartha has Hawaiians as its twin, rifts Chad-Njassa have as their twin island chain Line in Pacific etc. We can compare the Earth with its permamnent structural symmetry with other planets. Lunar and earthen tectonic megaforms: Imbrium, Oriental Mare and other have identical positions on their planets. It is evident if planet's 0-meridians are matched [1]. Lunar big rings have their places on the African old blocks. Tanganjica massive coincides with risen lunar region. Rodezian block with parts of Kibara, Lomagundy, Limpopo zones coincides with lunar Maria Nectaris and with their nearest rings. SW edge of these rings coincides with lunar Rupes Altai. Young structure of basin Congo coincides with risen block, its center- crater Delambr. Young ocean earthen structures have lunar images also. NW edge of Fecundidatis Maria and its floor coincides with Somali abissal plane, Davie ridge - with lunar Montes Pyrenaeus etc. Resume. The matrix of earthen tectonic forms is drawn on the Moon . The arc forms are cyclic renovating all the time on their own planet places with extending, shortening along one or another of their sides. Mountain arcs give birth to rear basalts. Question. Why 0-meridians of the Moon (center of its disk) and of the Earth (the decision of astronomers, 1884) have the same position relative to tectonic structures of their planets? Why earthen 0-meridian is chosen so

  15. Settlement-Compatible Lunar Transporation

    Science.gov (United States)

    Morgenthaler, G.

    Over the past few years we have published papers in this forum identifying, characterizing and advocating settlement-compatible transportation architectures for Mars. In the present paper, we do the same for the Moon and show evolutionary potentials for growth of lunar architectures into Mars architectures of the types discussed in our previous papers. The essence of a settlement-compatible architecture is that it yields a low recurring transportation cost and that the elements of the architecture are enduring, i.e., fully reusable with lifetimes on the order of Earth-based capital investments. Our previous papers have shown that extension of human habitation to other bodies in our Solar System is probably unaffordable with any other approach. The design of a settlement-compatible architecture begins with Earth launch. In our prior papers, we simply identified the Earth launch option as a fully reusable system with roughly Shuttle (or Atlas 5 or Delta 4 or Sea Launch or Ariane 5) capability, i.e. about 20 metric t. to low Earth orbit and a payload bay of dimensions about 5 m diameter x 15 to 20 m length. This is what the commercial market needs; this is where the traffic demand is; this is approximately the design point for a next-generation (after Shuttle) reusable launch vehicle. We continue in that vein for the present paper. Human mission advocates may argue it isn't big enough; that they need 80 metric t. payload to orbit. We answer that to achieve our cost criteria, there isn't much of a choice, and that the savings in launch cost will far outweigh the added expense for on-orbit assembly. Lunar transportation is considerably less demanding than Mars transportation. The main difference is in trip time. Because lunar trips are short, the crew habitat can be small, a la the Apollo Command Module, and the propulsion system to move it is also small by comparison. We analyze and depict a lunar transportation system based on crew elements adapted from the

  16. Relation and Influence of All Kinds of Unbalance Torques of Three Degrees of Freedom Air-bearing Spacecraft Simulator Caused by Gravity%重力引起的3自由度气浮台各类不平衡力矩关系及影响

    Institute of Scientific and Technical Information of China (English)

    李延斌; 向东; 高有华

    2015-01-01

    To improve three degrees of freedom air-bearing simulation accuracy and reduce the influence of unbalance torque caused by gravity, a method for calculating and compensating elastic unbalance torque is proposed. After computational model of static, plastic, gravity gradient and total unbalance torque being established, the relation and influence among all kinds of unbalance torque cause by gravity are analysis. It is discovered by contrast that static unbalance torque plays an important role when the platform mass center is far away from the rotation center. With the mass center approaching to rotation center, elastic unbalance torque is gradually becoming the main factor affecting the air-bearing platform balance. Then closing the distance between mass center and rotation center has nothing to do on reducing the unbalance torque, which shows that elastic unbalance torque is the main limiting factor for improving platform accuracy. The principle for mutual compensation between static unbalance torque and elastic unbalance torque is proposed and the compensation algorithm with automatic balancing system is provided. Experimental results have demonstrated application of the compensation method is an important channel for reducing unbalance torque.%为了提高3自由度气浮台的仿真精度,减小重力引起不平衡力矩的影响,提出气浮台弹性不平衡力矩的计算及补偿方法.建立气浮台重力引起的静态、弹性、重力梯度和总不平衡力矩的计算模型,分析重力引起的各类不平衡力矩关系及影响.通过对比发现气浮台质心位置相对回转中心较远时,静态不平衡力矩起主要作用.随着质心位置接近回转中心,弹性不平衡力矩逐渐成为影响气浮台平衡的主要因素,此时质心位置与回转中心距离的减小已不起作用,说明弹性不平衡力矩是制约气浮台精度提高的主要因素.提出静态不平衡力矩与弹性不平衡力矩相互补偿的原理,

  17. Fundamental physics and absolute positioning metrology with the MAGIA lunar orbiter

    Science.gov (United States)

    Dell'Agnello, Simone; Lops, Caterina; Delle Monache, Giovanni O.; Currie, Douglas G.; Martini, Manuele; Vittori, Roberto; Coradini, Angioletta; Dionisio, Cesare; Garattini, Marco; Boni, Alessandro; Cantone, Claudio; March, Riccardo; Bellettini, Giovanni; Tauraso, Roberto; Maiello, Mauro; Porcelli, Luca; Berardi, Simone; Intaglietta, Nicola

    2011-10-01

    MAGIA is a mission approved by the Italian Space Agency (ASI) for Phase A study. Using a single large-diameter laser retroreflector, a large laser retroreflector array and an atomic clock onboard MAGIA we propose to perform several fundamental physics and absolute positioning metrology experiments: VESPUCCI, an improved test of the gravitational redshift in the Earth-Moon system predicted by General Relativity; MoonLIGHT-P, a precursor test of a second generation Lunar Laser Ranging (LLR) payload for precision gravity and lunar science measurements under development for NASA, ASI and robotic missions of the proposed International Lunar Network (ILN); Selenocenter (the center of mass of the Moon), the determination of the position of the Moon center of mass with respect to the International Terrestrial Reference Frame/System (ITRF/ITRS); this will be compared to the one from Apollo and Lunokhod retroreflectors on the surface; MapRef, the absolute referencing of MAGIA's lunar altimetry, gravity and geochemical maps with respect to the ITRF/ITRS. The absolute positioning of MAGIA will be achieved thanks to: (1) the laboratory characterization of the retroreflector performance at INFN-LNF; (2) the precision tracking by the International Laser Ranging Service (ILRS), which gives two fundamental contributions to the ITRF/ITRS, i.e. the metrological definition of the geocenter (the Earth center of mass) and of the scale of length; (3) the radio science and accelerometer payloads; (4) support by the ASI Space Geodesy Center in Matera, Italy. Future ILN geodetic nodes equipped with MoonLIGHT and the Apollo/Lunokhod retroreflectors will become the first realization of the International Moon Reference Frame (IMRF), the lunar analog of the ITRF.

  18. Quantum Computation Toward Quantum Gravity

    Science.gov (United States)

    Zizzi, P. A.

    2001-08-01

    The aim of this paper is to enlighten the emerging relevance of Quantum Information Theory in the field of Quantum Gravity. As it was suggested by J. A. Wheeler, information theory must play a relevant role in understanding the foundations of Quantum Mechanics (the "It from bit" proposal). Here we suggest that quantum information must play a relevant role in Quantum Gravity (the "It from qubit" proposal). The conjecture is that Quantum Gravity, the theory which will reconcile Quantum Mechanics with General Relativity, can be formulated in terms of quantum bits of information (qubits) stored in space at the Planck scale. This conjecture is based on the following arguments: a) The holographic principle, b) The loop quantum gravity approach and spin networks, c) Quantum geometry and black hole entropy. From the above arguments, as they stand in the literature, it follows that the edges of spin networks pierce the black hole horizon and excite curvature degrees of freedom on the surface. These excitations are micro-states of Chern-Simons theory and account of the black hole entropy which turns out to be a quarter of the area of the horizon, (in units of Planck area), in accordance with the holographic principle. Moreover, the states which dominate the counting correspond to punctures of spin j = 1/2 and one can in fact visualize each micro-state as a bit of information. The obvious generalization of this result is to consider open spin networks with edges labeled by the spin -1/ 2 representation of SU(2) in a superposed state of spin "on" and spin "down." The micro-state corresponding to such a puncture will be a pixel of area which is "on" and "off" at the same time, and it will encode a qubit of information. This picture, when applied to quantum cosmology, describes an early inflationary universe which is a discrete version of the de Sitter universe.

  19. Cool flames at terrestrial, partial, and near-zero gravity

    Energy Technology Data Exchange (ETDEWEB)

    Foster, Michael; Pearlman, Howard [Department of Mechanical Engineering and Mechanics, Drexel University, 3141 Chestnut Street, Philadelphia, PA 19104 (United States)

    2006-10-15

    Natural convection plays an important role in all terrestrial, Lunar, and Martian-based, unstirred, static reactor cool flame and low-temperature autoignitions, since the Rayleigh number (Ra) associated with the self-heating of the reaction exceeds the critical Ra (approximately 600) for onset of convection. At near-zero gravity, Ra<600 can be achieved and the effects of convection suppressed. To systematically vary the Ra without varying the mixture stoichiometry, reactor pressure, or vessel size, cool flames are studied experimentally in a closed, unstirred, static reactor subject to different gravitational accelerations (terrestrial, 1g; Martian, 0.38g; Lunar, 0.16g; and reduced gravity, {approx}10{sup -2}g). Representative results show the evolution of the visible light emission using an equimolar n-butane:oxygen premixture at temperatures ranging from 320 to 350? deg C (593-623 K) at subatmospheric pressures. For representative reduced-gravity, spherically propagating cool flames, the flame radius based on the peak light intensity is plotted as a function of time and the flame radius (and speed) is calculated from a polynomial fit to data. A skeletal chemical kinetic Gray-Yang model developed previously for a one-dimensional, reactive-diffusive system by Fairlie and co-workers is extended to a two-dimensional axisymmetric, spherical geometry. The coupled species, energy, and momentum equations are solved numerically and the spatio-temporal variations in the temperature profiles are presented. A qualitative comparison is made with the experimental results. (author)

  20. Gravity and geoid model for South America

    Science.gov (United States)

    Blitzkow, Denizar; Oliveira Cancoro de Matos, Ana Cristina; do Nascimento Guimarães, Gabriel; Pacino, María Cristina; Andrés Lauría, Eduardo; Nunes, Marcelo; Castro Junior, Carlos Alberto Correia e.; Flores, Fredy; Orihuela Guevara, Nuris; Alvarez, Ruber; Napoleon Hernandez, José

    2016-04-01

    In the last 20 years, South America Gravity Studies (SAGS) project has undertaken an ongoing effort in establishing the fundamental gravity network (FGN); terrestrial, river and airborne relative gravity densifications; absolute gravity surveys and geoid (quasi-geoid) model computation for South America. The old FGN is being replaced progressively by new absolute measurements in different countries. In recent years, Argentina, Bolivia, Brazil, Ecuador, Paraguay and Venezuela organizations participated with relative gravity surveys. Taking advantage of the large amount of data available, GEOID2015 model was developed for 15°N and 57°S latitude and 30 ° W and 95°W longitude based on EIGEN-6C4 until degree and order 200 as a reference field. The ocean area was completed with mean free air gravity anomalies derived from DTU10 model. The short wavelength component was estimated using FFT. The global gravity field models EIGEN-6C4, DIR_R5 were used for comparison with the new model. The new geoid model has been evaluated against 1,319 GPS/BM, in which 592 are located in Brazil and the reminder in other countries. The preliminary RMS difference between GPS/BM and GEOID2015 throughout South America and in Brazil is 46 cm and 17 cm, respectively. New activities are carrying out with the support of the IGC (Geographic and Cartographic Institute) under the coordination of EPUSP/LTG and CENEGEO (Centro de Estudos de Geodesia). The new project aims to establish new gravity points with the A-10 absolute gravimeter in South America. Recent such surveys occurred in São Paulo state, Argentina and Venezuela.

  1. Secular pattern of aneurismal rupture with the lunar cycle and season.

    Science.gov (United States)

    Banfield, Jillian C; Abdolell, Mohamed; Shankar, Jai S

    2017-02-01

    Background The lunar cycle and seasons may be associated with rates of rupture of intracranial aneurysms, but the literature is mixed. Studies of the association between the lunar cycle and rates of aneurysm rupture used the eight qualitative moon phases. The purpose of this study was to assess any association of aneurysm rupture with the lunar cycle and with the season. Materials and methods We retrospectively reviewed all cases of subarachnoid haemorrhage secondary to ruptured intracranial aneurysm treated with endovascular coiling in our institution over a 10-year period. We included only cases with a known rupture date. We used the degree of illumination of the moon to quantitatively code the lunar cycle. Results A total of 212 cases were included in our analyses. The odds of aneurysm rupture were significantly greater ( p full moon) illuminated, as compared to the middle of the lunar cycle. The odds of rupture tended to be higher ( p = 0.059) in the summer, compared to autumn. Conclusions The odds of aneurysm rupture were greater when the moon was least illuminated (new moon) and most illuminated (full moon), compared to the middle of the lunar cycle.

  2. Beijing Lunar Declaration 2010: B) Technology and Resources; Infrastructures and Human Aspects; Moon, Space and Society

    Science.gov (United States)

    Arvidson, R.; Foing, B. H.; Plescial, J.; Cohen, B.; Blamont, J. E.

    2010-01-01

    We report on the Beijing Lunar Declaration endorsed by the delegates of the Global Lunar Conference/11th ILEWG Conference on Exploration and Utilisation of the Moon, held at Beijing on 30 May- 3 June 2010. Specifically we focus on Part B:Technologies and resources; Infrastructures and human aspects; Moon, Space, Society and Young Explorers. We recommend continued and enhanced development and implementation of sessions about lunar exploration, manned and robotic, at key scientific and engineering meetings. A number of robotic missions to the Moon are now undertaken independently by various nations, with a degree of exchange of information and coordination. That should increase towards real cooperation, still allowing areas of competition for keeping the process active, cost-effective and faster. - Lunar landers, pressurized lunar rover projects as presented from Europe, Asia and America are important steps that can create opportunities for international collaboration, within a coordinated village of robotic precursors and assistants to crew missions. - We have to think about development, modernization of existing navigation capabilities, and provision of lunar positioning, navigation and data relay assets to support future robotic and human exploration. New concepts and new methods for transportation have attracted much attention and are of great potential.

  3. Design and Construction of Manned Lunar Base

    Science.gov (United States)

    Li, Zhijie

    2016-07-01

    Building manned lunar base is one of the core aims of human lunar exploration project, which is also an important way to carry out the exploitation and utilization of lunar in situ resources. The most important part of manned lunar base is the design and construction of living habitation and many factors should be considered including science objective and site selection. Through investigating and research, the scientific goals of manned lunar base should be status and characteristics ascertainment of lunar available in situ resources, then developing necessary scientific experiments and utilization of lunar in situ resources by using special environment conditions of lunar surface. The site selection strategy of manned lunar base should rely on scientific goals according to special lunar surface environment and engineering capacity constraints, meanwhile, consulting the landing sites of foreign unmanned and manned lunar exploration, and choosing different typical regions of lunar surface and analyzing the landform and physiognomy, reachability, thermal environment, sunlight condition, micro meteoroids protection and utilization of in situ resources, after these steps, a logical lunar living habitation site should be confirmed. This paper brings out and compares three kinds of configurations with fabricating processes of manned lunar base, including rigid module, flexible and construction module manned lunar base. 1.The rigid habitation module is usually made by metal materials. The design and fabrication may consult the experience of space station, hence with mature technique. Because this configuration cannot be folded or deployed, which not only afford limit working and living room for astronauts, but also needs repetitious cargo transit between earth and moon for lunar base extending. 2. The flexible module habitation can be folded in fairing while launching. When deploying on moon, the configuration can be inflatable or mechanically-deployed, which means under

  4. Unimodular Theory of Gravity and Inflation

    CERN Document Server

    Cho, Inyong

    2014-01-01

    We study inflation and its scalar perturbations in the unimodular theory of gravity. When the unimodular parameter is $\\xi=6$, the classical picture of inflation such as the slow-roll parameters, the number of $e$-foldings and the scale of the scalar field, can be reproduced in the unimodular theory because it recovers the background equations of the standard theory of general relativity. Considering the scalar perturbation, the unimodular gravity constrains the gauge degree of freedom, but the perturbation equations are similar to those in general relativity. For $\\xi \

  5. Effective constraints of loop quantum gravity

    CERN Document Server

    Bojowald, M; Kagan, M; Skirzewski, A; Bojowald, Martin; Hernandez, Hector; Kagan, Mikhail; Skirzewski, Aureliano

    2006-01-01

    Within a perturbative cosmological regime of loop quantum gravity corrections to effective constraints are computed. This takes into account all inhomogeneous degrees of freedom relevant for scalar metric modes around flat space and results in explicit expressions for modified coefficients and of higher order terms. It also illustrates the role of different scales determining the relative magnitude of corrections. Our results demonstrate that loop quantum gravity has the correct classical limit, at least in its sector of cosmological perturbations around flat space, in the sense of perturbative effective theory.

  6. The average acceleration approach applied to gravity coefficients recovery based on GOCE orbits

    Directory of Open Access Journals (Sweden)

    Huang Qiang

    2012-11-01

    Full Text Available The average acceleration approach was applied to recover a gravity field model Model_ACA from GOCE precise science orbits from September 2 to November 2, 2010, and furthermore a so called sequential least square adjustment was used. The model was compared with other gravity field models based on CHAMP, GRACE and GOCE. The result shows that the model is superior to gravity field based on CHAMP, and with higher accuracy than other international gravity field models based on only GOCE data before 80 degree. The degree geoid height of Model_ACA reaches 3 cm up to 90 degree and order.

  7. Interior Alaska Bouguer Gravity Anomaly

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A 1 kilometer Complete Bouguer Anomaly gravity grid of interior Alaska. Only those grid cells within 10 kilometers of a gravity data point have gravity values....

  8. Hybrid theory of gravity

    Science.gov (United States)

    Kan, Nahomi; Maki, Takuya; Shiraishi, Kiyoshi

    2016-10-01

    We propose a model of gravity in which a General Relativity metric tensor and an effective metric generated from a single scalar formulated in geometric scalar gravity are mixed. We show that the model yields the exact Schwarzschild solution, along with accelerating behavior of scale factors in cosmological solutions.

  9. No consistent bimetric gravity?

    CERN Document Server

    Deser, S; Waldron, A

    2013-01-01

    We discuss the prospects for a consistent, nonlinear, partially massless (PM), gauge symmetry of bimetric gravity (BMG). Just as for single metric massive gravity, ultimate consistency of both BMG and the putative PM BMG theory relies crucially on this gauge symmetry. We argue, however, that it does not exist.

  10. Self-Dual Gravity

    CERN Document Server

    Krasnov, Kirill

    2016-01-01

    Self-dual gravity is a diffeomorphism invariant theory in four dimensions that describes two propagating polarisations of the graviton and has a negative mass dimension coupling constant. Nevertheless, this theory is not only renormalisable but quantum finite, as we explain. We also collect various facts about self-dual gravity that are scattered across the literature.

  11. Gravity Driven Universe

    Science.gov (United States)

    Masters, Roy

    2010-03-01

    Flowing global gravitation initially produced space without time or mass. Space-time and mass are properties of flowing global gravitation. From its fabric, primal mass spins spontaneously giving rise to local gravitational space-time curvatures. Global gravity is the unifying background field. Gravity began flowing from its singularity with a big whoosh. It curves with angular rotational precession, creating a spatial geometry similar to the windings of a ball of string. Three-dimensional global gravity swirls locally into massive densities. Concurrently with these densities, local gravity curvatures of space-time arise. The expanse between celestial objects is not completely empty, void space as generally believed; it is antecedent gravity, a prerequisite associated field necessary for originating the first quantum particles. Gravity is dark energy; gravity's spin, as the second fundamental force, is electromagnetic dark matter. Electromagnetic masses attract then gravity compresses hot, dense and small---then bang, the first hydrogen star of which there are many. There may have been many big bangs, but no Big Bang that ultimately created the universe.

  12. Lunar interaction with the solar wind - Effects on lunar electrical conductivity estimates

    Science.gov (United States)

    Goldstein, B. E.

    1978-01-01

    The lunar electromagnetic response, measured at very low frequencies with the moon in the solar wind, is used to evaluate interior electrical conductivity at great depth and to determine limits on the size of possible lunar core. A theory is developed wherein compression of the magnetic field in the lunar tail cavity caused by inflowing plasma at the lunar limbs and in the lunar wake, bends the magnetic field in the lunar interior and thereby alters the tangential component of magnetic field observed on the dayside surface. This theory strongly indicates that cavity fringing cannot explain the enhanced East-West fluctuations. It is proposed that the East-West fluctuations might be due to diamagnetic currents caused by lunar surface photoelectrons in the lunar terminator region.

  13. Lunar base scenario cost estimates: Lunar base systems study task 6.1

    Science.gov (United States)

    1988-01-01

    The projected development and production costs of each of the Lunar Base's systems are described and unit costs are estimated for transporting the systems to the lunar surface and for setting up the system.

  14. First Results from NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE)

    Science.gov (United States)

    Elphic, R.; Colaprete, A.; Horanyi, M; Mahaffy, Paul; Boroson, D.; Delory, G.; Noble, s; Hine, B; Salute, J.

    2013-01-01

    performed at an orbit with periapsis between 20-60 km. This orbit must be constantly managed due to the Moon's highly inhomogeneous gravity field. During the Science Phase, the moon will rotate more than three times underneath the LADEE orbit. LADEE employs a high heritage instrument payload: a Neutral Mass Spectrometer (NMS) from Goddard Space Flight Center, an Ultraviolet/Visible Spectrometer (UVS) from Ames Research Center, and a dust detection experiment (LDEX) from the University of Colorado/LASP. It will also carry the Lunar Laser Communications Demonstration (LLCD) as a technology demonstration. The LLCD is funded by the Human Exploration Operations Mission Directorate (HEOMD), managed by GSFC, and built by the MIT Lincoln Lab. Contingent upon LADEE's successful lunar orbit insertion and checkout, we will report the early results from the science investigations.

  15. A chemical and petrological model of the lunar crust

    Science.gov (United States)

    Spudis, Paul D.; Davis, Philip A.

    1987-01-01

    Information is given on the composition and structure of the lunar crust. A lunar model is illustrated, indicating that it has essentially two layers, anorthositic mixed rocks overlaying a generally noritic crystalline basement. Implications relative to lunar evolution are discussed.

  16. Possible biomedical applications and limitations of a variable-force centrifuge on the lunar surface: A research tool and an enabling resource

    Science.gov (United States)

    Cowing, Keith L.

    1992-01-01

    Centrifuges will continue to serve as a valuable research tool in gaining an understanding of the biological significance of the inertial acceleration due to gravity. Space- and possibly lunar-based centrifuges will play a significant and enabling role with regard to the human component of future lunar and martian exploration, both as a means of accessing potential health and performance risks and as a means of alleviating these risks. Lunar-based centrifuges could be particularly useful as part of a program of physiologic countermeasures designed to alleviate the physical deconditioning that may result from prolonged exposure to a 1/6-g environment. Centrifuges on the lunar surface could also be used as part of a high-fidelity simulation of a trip to Mars. Other uses could include crew readaptation to 1 g, waste separation, materials processing, optical mirror production in situ on the Moon, and laboratory specimen separation.

  17. Lunar Dust Effects on Spacesuit Systems: Insights from the Apollo Spacesuits

    Science.gov (United States)

    Christoffersen, Roy; Lindsay, John R.; Noble, Sarah K.; Meador, Mary Ann; Kosmo, Joseph J.; Lawrence, J. Anneliese; Brostoff, Lynn; Young, Amanda; McCue, Terry

    2008-01-01

    Systems and components of selected Apollo A7L/A7LB flight-article spacesuits that were worn on the lunar surface have been studied to determine the degree to which they suffered contamination, abrasion and wear or loss of function due to effects from lunar soil particles. Filter materials from the lithium hydroxide (LiOH) canisters from the Apollo Command Module were also studied to determine the amount and type of any lunar dust particles they may have captured from the spacecraft atmosphere. The specific spacesuit study materials include the outermost soft fabric layers on Apollo 12 and 17 integrated thermal micrometeorite garment assemblies and outermost fabrics on Apollo 17 extravehicular pressure gloves. In addition, the degree of surface wear in the sealed wrist rotation bearing from Apollo 16 extravehicular and intravehicular pressure gloves was evaluated and compared. Scanning electron microscope examination of the Apollo 12 T-164 woven TeflonO fabric confirms the presence of lunar soil particles and the ability of these particles to cause separation and fraying of the Teflon fibers. Optical imaging, chemical analysis and particle sampling applied to the outer fabric of the Apollo 17 spacesuit has identified Ti as a potentially useful chemical marker for comparing the amount of lunar soil retained on different areas of the spacesuit outer fabric. High-yield particle sampling from the Apollo 17 fabric surfaces using adhesive tape found 80% of particles on the fabric are lunar soil particles averaging 10.5 m in diameter, with the rest being intrinsic fabric materials or environmental contaminants. Analysis of the mineralogical composition of the lunar particles found that on a grain-count basis the particle population is dominated by plagioclase feldspar and various types of glassy particles derived mostly from soil agglutinates, with a subordinate amount of pyroxene. On a grain size basis, however, the pyroxene grains are generally a factor of 2 larger than

  18. Lunar domes properties and formation processes

    CERN Document Server

    Lena, Raffaello; Phillips, Jim; Chiocchetta, Maria Teresa

    2013-01-01

    Lunar domes are structures of volcanic origin which are usually difficult to observe due to their low heights. The Lunar Domes Handbook is a reference work on these elusive features. It provides a collection of images for a large number of lunar domes, including telescopic images acquired with advanced but still moderately intricate amateur equipment as well as recent orbital spacecraft images. Different methods for determining the morphometric properties of lunar domes (diameter, height, flank slope, edifice volume) from image data or orbital topographic data are discussed. Additionally, multispectral and hyperspectral image data are examined, providing insights into the composition of the dome material. Several classification schemes for lunar domes are described, including an approach based on the determined morphometric quantities and spectral analyses. Furthermore, the book provides a description of geophysical models of lunar domes, which yield information about the properties of the lava from which the...

  19. Electrostatic Characterization of Lunar Dust Simulants

    Science.gov (United States)

    Calle, C. I.; Buhler, C. R.; Ritz, M. L.

    2008-01-01

    Lunar dust can jeopardize exploration activities due to its ability to cling to most surfaces. In this paper, we report on our measurements of the electrostatic properties of the lunar soil simulants. Methods have been developed to measure the volume resistivity, dielectric constant, chargeability, and charge decay of lunar soil. While the first two parameters have been measured in the past [Olhoeft 1974], the last two have never been measured directly on the lunar regolith or on any of the Apollo samples. Measurements of the electrical properties of the lunar samples are being performed in an attempt to answer important problems that must be solved for the development of an effective dust mitigation technology, namely, how much charge can accumulate on the dust and how long does the charge remain on surfaces. The measurements will help develop coatings that are compatible with the intrinsic electrostatic properties of the lunar regolith.

  20. A lunar dust simulant: CLDS-i

    Science.gov (United States)

    Tang, Hong; Li, Xiongyao; Zhang, Sensen; Wang, Shijie; Liu, Jianzhong; Li, Shijie; Li, Yang; Wu, Yanxue

    2017-02-01

    Lunar dust can make serious damage to the spacecrafts, space suits, and health of astronauts, which is one of the most important problems faced in lunar exploration. In the case of rare lunar dust sample, CLDS-i with high similarity to the real lunar dust is an important objective for studying dust protection and dust toxicity. The CLDS-i developed by the Institute of Geochemistry Chinese Academy Sciences contains ∼75 vol% glass and a little nanophase metal iron (np-Fe0), and with a median particle size about 500 nm. The CLDS-i particles also have complicated shape and sharp edges. These properties are similar to those of lunar dust, and make the CLDS-i can be applied to many fields such as the scientific researches, the treatment technology and toxicological study of lunar dust.

  1. Searching for Lunar Tidal Deformations with LRO/LOLA

    Science.gov (United States)

    Barker, M. K.; Mazarico, E.; Neumann, G. A.; Zuber, M. T.; Smith, D. E.

    2013-12-01

    The Moon exhibits a tidal gravity field signature due to the difference in the gravitational force of the Earth and Sun at the Moon's surface and its center of mass. The Moon responds elastically by deforming into an ellipsoid that is slightly squashed along the limb and bulged on the near and far sides, with a maximum radial displacement of ~50 cm (with respect to a perfect sphere) near the sub-Earth point and its antipode. Variations in the Earth-Moon distance and geometric librations cause the bulge pattern to fluctuate in amplitude and shift in position on the surface, so that the surface height at any given geographic location moves up and down with a dominant period of 27.555 days and an amplitude of up to ~10 cm. Studying the detailed shape and behavior of these deformations can yield important information on the Moon's physical properties, such as the density distribution and bulk elastic parameters. After ~4.5 years of operation, the Lunar Orbiter Laser Altimeter (LOLA) aboard the Lunar Reconnaissance Orbiter (LRO) has collected over 6 billion measurements of surface height with a vertical precision of ~10 cm and an accuracy of ~1 m. The LOLA dataset contains more than 10 million crossovers, instances when two ground-tracks intersect. Each crossover represents the measurement of surface height at one location and at two different times, thereby providing a way of measuring tidal deformations. Here we present preliminary results of efforts to detect and constrain lunar tidal deformations using a sample of the highest-quality LOLA crossovers.

  2. Multi-state autonomous drilling for lunar exploration

    OpenAIRE

    Chen Chongbin; Quan Qiquan; Shi Xiaomeng; Deng Zongquan; Tang Dewei; Jiang Shengyuan

    2016-01-01

    Due to the lack of information of subsurface lunar regolith stratification which varies along depth, the drilling device may encounter lunar soil and lunar rock randomly in the drilling process. To meet the load safety requirements of unmanned sampling mission under limited orbital resources, the control strategy of autonomous drilling should adapt to the indeterminable lunar environments. Based on the analysis of two types of typical drilling media (i.e., lunar soil and lunar rock), this pap...

  3. Antarctic Crustal Thickness from Gravity Inversion

    Science.gov (United States)

    Vaughan, A. P.; Kusznir, N. J.; Ferraccioli, F.; Jordan, T. A.

    2013-12-01

    Using gravity anomaly inversion, we have produced the first comprehensive regional maps of crustal thickness and oceanic lithosphere distribution for Antarctica and the Southern Ocean. We determine Moho depth, crustal basement thickness, continental lithosphere thinning (1-1/β) and ocean-continent transition location using a 3D spectral domain gravity inversion method, which incorporates a lithosphere thermal gravity anomaly correction. The continental lithosphere thinning distribution, used to define the initial thermal model temperature perturbation is derived from the gravity inversion and uses no a priori isochron information; as a consequence the gravity inversion method provides a prediction of ocean-continent transition location, which is independent of ocean isochron information. The gravity anomaly contribution from ice thickness is included in the gravity inversion, as is the contribution from sediments which assumes a compaction controlled sediment density increase with depth. Data used in the gravity inversion are elevation and bathymetry, free-air gravity anomaly, the most recent Bedmap2 ice thickness and bedrock topography compilation south of 60 degrees south (Fretwell et al., 2013) and relatively sparse constraints on sediment thickness. Our gravity inversion study predicts thick crust (> 45 km) under interior East Antarctica penetrated by narrow continental rifts that feature relatively thinner crust. The East Antarctic Rift System (EARS) is a major Permian to Cretaceous age rift system that appears to extend from the continental margin at the Lambert Rift to the South Pole region, a distance of 2500 km. This is comparable in scale to the well-studied East African rift system. Intermediate crustal thickness with an inferred linear rift fabric is predicted under Coates Land. An extensive region of either thick oceanic crust or highly thinned continental crust is predicted offshore Oates Land and north Victoria Land, and also off West Antarctica

  4. The Thermal Hogan - A Means of Surviving the Lunar Night

    Science.gov (United States)

    Fruitwala, Neelay; Ungar, Eugene; Cornwell, John

    2013-01-01

    document describes the Thermal Hogan, a new shelter concept that would be used on the Moon to moderate the extreme nighttime temperatures, allowing survival of equipment with minimal heater power. It is lightweight, has few mechanical parts, and would be relatively easy to deploy on the Moon. The Lunar Hogan has two parts: an insulated shelter and a thermal mass. The shelter is constructed of multilayer insulation (MLI) draped over a structural framework. Entry and egress are accomplished either by raising the structure or via a door constructed of the same MLI material as the shelter. The thermal mass can be manufactured from locally available materials, either by piling substantially sized rocks to a depth of 0.25 meter, or by filling a 0.25-meter-deep conductive honeycomb-like structure with lunar dust. For ease of transport, the structural framework and honeycomb can be collapsible. The door can be opened by pushing on it in either direction. Gravity would cause it to close and it could be sealed via magnetic strips on the doorframe.

  5. Quarantine testing and biocharacterization of lunar materials

    Science.gov (United States)

    Taylor, G. R.; Mieszkuc, B. J.; Simmonds, R. C.; Walkinshaw, C. H.

    1975-01-01

    Quarantine testing was conducted to ensure the safety of all life on earth. The plants and animals which were exposed to lunar material were carefully observed for prolonged periods to determine if any mutation or changes in growing characteristics and behavior occurred. The quarantine testing was terminated after the Apollo 14 flight when it became apparent that previously returned lunar material contained no potentially harmful agents. Further biological experimentation with the lunar material was conducted to determine its chemical, physical, and nutritional qualities.

  6. Distillation and Air Stripping Designs for the Lunar Surface

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Air stripping and distillation are two different gravity-based methods, which may be applied to the purification of wastewater on the lunar base. These gravity-based solutions to water processing are robust physical separation techniques, which may be advantageous to many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation models and air stripping models. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for the for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Distillation processes are modeled separately and in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams. Components of the wastewater streams are ranked by Henry s Law Constant and the suitability of air stripping in the purification of wastewater in terms of component removal is evaluated. Scaling factors for distillation and air stripping columns are presented to account for the difference in the lunar gravitation environment. Commercially available distillation and air stripping units which are considered suitable for Exploration Life Support

  7. Distillation and Air Stripping Designs for the Lunar Surface

    Science.gov (United States)

    Boul, Peter J.; Lange, Kevin E.; Conger, Bruce; Anderson, Molly

    2009-01-01

    Air stripping and distillation are two different gravity-based methods, which may be applied to the purification of wastewater on the lunar base. These gravity-based solutions to water processing are robust physical separation techniques, which may be advantageous to many other techniques for their simplicity in design and operation. The two techniques can be used in conjunction with each other to obtain high purity water. The components and feed compositions for modeling waste water streams are presented in conjunction with the Aspen property system for traditional stage distillation models and air stripping models. While the individual components for each of the waste streams will vary naturally within certain bounds, an analog model for waste water processing is suggested based on typical concentration ranges for these components. Target purity levels for the for recycled water are determined for each individual component based on NASA s required maximum contaminant levels for potable water Distillation processes are modeled separately and in tandem with air stripping to demonstrate the potential effectiveness and utility of these methods in recycling wastewater on the Moon. Optimum parameters such as reflux ratio, feed stage location, and processing rates are determined with respect to the power consumption of the process. Multistage distillation is evaluated for components in wastewater to determine the minimum number of stages necessary for each of 65 components in humidity condensate and urine wastewater mixed streams. Components of the wastewater streams are ranked by Henry s Law Constant and the suitability of air stripping in the purification of wastewater in terms of component removal is evaluated. Scaling factors for distillation and air stripping columns are presented to account for the difference in the lunar gravitation environment. Commercially available distillation and air stripping units which are considered suitable for Exploration Life Support

  8. Lectures on the Lunar Theory

    Science.gov (United States)

    Adams, John Couch; Sampson, R. A.

    2015-10-01

    1. Historical sketch; 2. Accelerations of the Moon relative to the Earth; 3. The Sun's coordinates in terms of the time; 4. The variation; 5. The variation (continued); 6. The variation (continued); 7. Correction of approximate solutions; 8. The parallactic inequality; 9. The parallactic inequality (continued);10. The annual equation; 11. The equation of the centre and the evection; 12. The evection and the motion of the apse; 13. The motion of the apse, and the change of the eccentricity; 14. The lattitude and the motion of the node; 15. Motion in an orbit of any inclination; 16. Motion in an orbit of any inclination (continued); 17. On Hill's method of treating the Lunar Theory; 18. On Hill's method of treating the Lunar Theory (continued).

  9. Advances in lunar exploration detectors

    Institute of Scientific and Technical Information of China (English)

    XU Tao; OUYANG Ziyuan; LI Chunlai; XU Lin

    2005-01-01

    Due to the rapid development of modem science and technology, many advanced sensors have been put into use to explore our solar system, including the Moon. With the help of those detectors,we can retrieve more information to about the Moon' s composition and evolution. The Clementine (January, 1994), Lunar Prospector ( January, 1998) and especially Smart-1 ( September, 2003 ) launched successively have demonstrated the next-generation planet exploration techniques. Now China has decided to send a probe to the Moon. So it is necessary to overview the development of detectors used for the scientific observation of the Moon. In this paper, some main instruments used to acquire geochemistry information are described, which include UV-VIS-NIR CCD imaging spectroscope, neutronray, gamma-ray, and X-ray spectrometers. Moreover, the payloads of China' s first lunar satellite are introduced briefly.

  10. Origin of lunar feldspathic rocks

    Science.gov (United States)

    Walker, D.; Grove, T. L.; Longhi, J.; Stolper, E. M.; Hays, J. F.

    1973-01-01

    Melting experiments and petrographic studies of lunar feldspathic rocks reveal possible genetic relationships among several compositionally and mineralogically distinct groups of lunar rocks and soil fragments. Dry, low PO2 partial melting of crustal anorthositic norites of the anorthositic-noritic-troctolitic (ANT) suite produces liquids of the KREEP-Fra Mauro basalt type; dry, low PO2 partial melting of pink spinel troctolite (PST) produces liquids of the 'very high alumina basalt' or microtroctolite type. Both ANT and PST are probable components of the primitive terra crust. If crystal fractionation in a cooling basaltic liquid could have produced such a crust, it would also produce a mafic interior capable of yielding mare basalts by later remelting at depth.

  11. Infrared Lunar Laser Ranging at Calern : Impact on Lunar Dynamics

    Science.gov (United States)

    Viswanathan, Vishnu; Fienga, Agnes; Manche, Herve; Gastineau, Mickael; Courde, Clement; Torre, Jean Marie; Exertier, Pierre; Laskar, Jacques

    2017-04-01

    Introduction: Since 2015, in addition to the traditional green (532nm), infrared (1064nm) has been the preferred wavelength for lunar laser ranging at the Calern lunar laser ranging (LLR) site in France. Due to the better atmospheric transmission of IR with respect to Green, nearly 3 times the number of normal points have been obtained in IR than in Green [1]. Dataset: In our study, in addition to the historical data obtained from various other LLR sites, we include the recent IR normal points obtained from Calern over the 1 year time span (2015-2016), constituting about 4.2% of data spread over 46 years of LLR. Near even distribution of data provided by IR on both the spatial and temporal domain, helps us to improve constraints on the internal structure of the Moon modeled within the planetary ephemeris : INPOP [2]. Data reduction: IERS recommended models have been used in the data reduction software GINS (GRGS,CNES) [3]. Constraints provided by GRAIL [4], on the Lunar gravitational potential and Love numbers have been taken into account in the least-square fit procedure. Earth orientation parameters from KEOF series have been used as per a recent study [5]. Results: New estimates on the dynamical parameters of the lunar core will be presented. Acknowledgements: We thank the lunar laser ranging observers at Observatoire de la Côte d'Azur, France, McDonald Observatory, Texas, Haleakala Observatory, Hawaii, and Apache Point Observatory in New Mexico for providing LLR observations that made this study possible. The research described in this abstract was carried out at Geoazur-CNRS, France, as a part of a PhD thesis funded by Observatoire de Paris and French Ministry of Education and Research. References: [1] Clement C. et al. (2016) submitted to A&A [2] Fienga A. et al. (2015) Celest Mech Dyn Astr, 123: 325. doi:10.1007/s10569-015-9639-y [3] Viswanathan V. et al. (2015) EGU, Abstract 18, 13995 [4] Konopliv A. S. et al. (2013) J. Geophys. Res. Planets, 118, 1415

  12. 月球探测计划研究进展%Progress in international lunar exploration programs

    Institute of Scientific and Technical Information of China (English)

    郑伟; 许厚泽; 钟敏; 刘成恕; 员美娟

    2012-01-01

    详细介绍了国内外已实施的苏联“月球号”和“探测器号”,美国“先驱者号”、“徘徊者号”、“勘测者号”、“月球轨道器号”、“阿波罗号”、“克莱门汀号”、“月球勘探者号”和“月球勘测轨道飞行器号”,日本“飞天号”和“月亮女神1号”,欧洲“智能1号”,中国“嫦娥一、二号”,印度“月船1号”等探测工具和未来实施的探月计划.详细介绍了美国GRAIL月球重力双星计划的总体概述、关键载荷和科学目标.具体阐述了我国下一代月球卫星重力梯度测量工程的实施建议和重要意义.认为我国下一代月球卫星重力梯度测量工程的成功实施将逐渐打破“太空战”的威胁,使世界和平得到有力维护.%Firstly, the operated lunar exploration programs including "Luna and Detector" in USSR, "Pioneer, Ranger, Surveyor, Lunar Orbiter, Apollo, Clementine, Lunar Prospector and Lunar Reconnaissance Orbiter" in USA, "Hiten and Selene-1" in Japan, "Smart-l" in Europe, "Chang'e-1/2" in China and "Chandrayaan-1" in India, and the planned lunar exploration missions in the world are comprehensively introduced. Secondly, the general overview, key payloads and scientific objectives of the GRAIL lunar satellite gravity exploration program are recommended in detail. Finally, the implementation suggestions and important significances of the next-generation lunar satellite gravity gradiometry mission in China are elaborated. The successful implementation of the next-generation lunar satellite gravity gradiometry mission in China is of great benefit to breaking a threat of "space war" and safeguarding world peace.

  13. Dual massive gravity

    Energy Technology Data Exchange (ETDEWEB)

    Morand, Kevin, E-mail: Kevin.Morand@lmpt.univ-tours.fr [Laboratoire de Mathematiques et Physique Theorique, Universite Francois-Rabelais Tours, Federation Denis Poisson - CNRS, Parc de Grandmont, 37200 Tours (France); Solodukhin, Sergey N., E-mail: Sergey.Solodukhin@lmpt.univ-tours.fr [Laboratoire de Mathematiques et Physique Theorique, Universite Francois-Rabelais Tours, Federation Denis Poisson - CNRS, Parc de Grandmont, 37200 Tours (France)

    2012-08-29

    The linearized massive gravity in three dimensions, over any maximally symmetric background, is known to be presented in a self-dual form as a first order equation which encodes not only the massive Klein-Gordon type field equation but also the supplementary transverse-traceless conditions. We generalize this construction to higher dimensions. The appropriate dual description in d dimensions, additionally to a (non-symmetric) tensor field h{sub {mu}{nu}}, involves an extra rank-(d-1) field equivalently represented by the torsion rank-3 tensor. The symmetry condition for h{sub {mu}{nu}} arises on-shell as a consequence of the field equations. The action principle of the dual theory is formulated. The focus has been made on four dimensions. Solving one of the fields in terms of the other and putting back in the action one obtains two other equivalent formulations of the theory in which the action is quadratic in derivatives. In one of these representations the theory is formulated entirely in terms of a rank-2 non-symmetric tensor h{sub {mu}{nu}}. This quadratic theory is not identical to the Fierz-Pauli theory and contains the coupling between the symmetric and antisymmetric parts of h{sub {mu}{nu}}. Nevertheless, the only singularity in the propagator is the same as in the Fierz-Pauli theory so that only the massive spin-2 particle is propagating. In the other representation, the theory is formulated in terms of the torsion rank-3 tensor only. We analyze the conditions which follow from the field equations and show that they restrict to 5 degrees of freedom thus producing an alternative description to the massive spin-2 particle. A generalization to higher dimensions is suggested.

  14. Zwei-Dreibein Gravity : A Two-Frame-Field Model of 3D Massive Gravity

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; de Haan, Sjoerd; Hohm, Olaf; Merbis, Wout; Townsend, Paul K.

    2013-01-01

    We present a generally covariant and parity-invariant two-frame field ("zwei-dreibein") action for gravity in three space-time dimensions that propagates two massive spin-2 modes, unitarily, and we use Hamiltonian methods to confirm the absence of unphysical degrees of freedom. We show how

  15. Gravity field estimation from future space missions - TOPEX/POSEIDON, Gravity Probe B, and ARISTOTELES

    Science.gov (United States)

    Pavlis, Erricos C.

    Accurate knowledge of the gravity field is a firm requirement in any study of Planet Earth. Space techniques have so far demonstrated their superiority in the global mapping of the gravity field based on ground tracking and altimeter data mostly. Numerical and analytical simulation studies of the upcoming geophysically relevant missions that will most likely carry GPS receivers, indicate significant improvements in the accuracy as well as the resolution of the gravity field. TOPEX will improve by some two orders of magnitude the long wavelength part (to degree about 20), while GP-B will contribute in the long as well as medium wavelength part of the spectrum (up to degree about 60). The gradiometer measurements on ARISTOTELES will contribute in the medium and short wavelength regions (from degree 30 up); GPS tracking of the spacecraft though will provide additional information for the long wavelength gravity and will help resolve it to accuracies comparable to those obtained from GP-B. With the mean rms coefficient error per degree kept below 10 exp -10, geophysical signals such as the post-glacial rebound, tidal variations, and secular and periodic variations of the zonal field rise above the noise level and become readily observable processes.

  16. Zwei-Dreibein Gravity : A Two-Frame-Field Model of 3D Massive Gravity

    NARCIS (Netherlands)

    Bergshoeff, Eric A.; de Haan, Sjoerd; Hohm, Olaf; Merbis, Wout; Townsend, Paul K.

    2013-01-01

    We present a generally covariant and parity-invariant two-frame field ("zwei-dreibein") action for gravity in three space-time dimensions that propagates two massive spin-2 modes, unitarily, and we use Hamiltonian methods to confirm the absence of unphysical degrees of freedom. We show how zwei-drei

  17. Production of Synthetic Lunar Simulants Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Zybek Advanced Products has proven the ability to produce industrial quantities of lunar simulant materials, including glass, agglutinate and melt breccias. These...

  18. Electrical power integration for lunar operations

    Science.gov (United States)

    Woodcock, Gordon

    1992-01-01

    Electrical power for future lunar operations is expected to range from a few kilowatts for an early human outpost to many megawatts for industrial operations in the 21st century. All electrical power must be imported as chemical, solar, nuclear, or directed energy. The slow rotation of the Moon and consequent long lunar night impose severe mass penalties on solar systems needing night delivery from storage. The cost of power depends on the cost of the power systems the cost of its transportation to the Moon, operating cost, and, of course, the life of the power system. The economic feasibility of some proposed lunar ventures depends in part on the cost of power. This paper explores power integration issues, costs, and affordability in the context of the following representative lunar ventures: (1) early human outpost (10 kWe); (2) early permanent lunar base, including experimental ISMU activities (100 kWe); (3) lunar oxygen production serving an evolved lunar base (500 kWe); (4) lunar base production of specialized high-value products for use on Earth (5 kWe); and (5) lunar mining and production of helium-3 (500 kWe). The schema of the paper is to project likely costs of power alternatives (including integration factors) in these power ranges, to select the most economic, to determine power cost contribution to the product or activities, to estimate whether the power cost is economically acceptable, and, finally, to offer suggestions for reaching acceptability where cost problems exist.

  19. Lunar Ultraviolet Telescope Experiment (LUTE) overview

    Science.gov (United States)

    McBrayer, R. O.; Frazier, J.; Nein, M.

    1993-09-01

    The Lunar Ultraviolet Telescope Experiment (LUTE) is a 1-m aperture telescope for imaging the stellar ultraviolet spectrum from the lunar surface. The aspects of Lute's educational value and the information it can provide on designing for the long-term exposure to the lunar environment are important considerations. This paper briefly summarizes the status of the phase A study by the Marshall Space Flight Center's (MSFC) LUTE Task Team. The primary focus will be a discussion of the merits of LUTE as a small and relatively inexpensive project that benefits a wide spectrum of interests and could be operating on the lunar surface by the turn of the century.

  20. Lunar concrete: Prospects and challenges

    Science.gov (United States)

    Khitab, Anwar; Anwar, Waqas; Mehmood, Imran; Kazmi, Syed Minhaj Saleem; Munir, Muhammad Junaid

    2016-02-01

    The possibility of using concrete as a construction material at the Moon surface is considered. Dissimilarities between the Earth and the Moon and their possible effects on concrete are also emphasized. Availability of constituent materials for concrete at lunar surface is addressed. An emphasis is given to two types of materials, namely, hydraulic concrete and sulfur concrete. Hydraulic concrete necessitates the use of water and sulfur concrete makes use of molten sulfur in lieu of cement and water.

  1. Radioactivities in returned lunar materials

    Science.gov (United States)

    Fireman, E. L.

    1977-01-01

    Results from a carbon-14 study in size fractions of lunar soil are reported. The 10 to 30 micrometers and 74 to 124 micrometers size fraction results were supplemented by 30 to 37 micrometers results that are given in this report. The gases from the less than 10 micrometers fraction were extracted and purified and carbon-14 counting is now in progress. Meteorites were also studied using carbon-14, with emphasis directed to those recently discovered in the Antarctic.

  2. Lunar Pyroclastic Eruptions: Basin Volcanism's Dying Gasps

    Science.gov (United States)

    Kramer, G. Y.; Nahm, A.; McGovern, P. J.; Kring, D. A.

    2011-12-01

    The relationship between mare volcanism and impact basins has long been recognized, although the degree of influence basin formation has on volcanism remains a point of contention. For example, did melting of magma sources result from thermal energy imparted by a basin-forming event? Did basin impacts initiate mantle overturn of the unstable LMO cumulate pile, causing dense ilmenite to sink and drag radioactive KREEPy material to provide the thermal energy to initiate melting of the mare sources? Did the dramatically altered stress states provide pathways ideally suited for magma ascent? The chemistry of sampled lunar volcanic glasses indicates that they experienced very little fractional crystallization during their ascent to the surface - they have pristine melt compositions. Volatile abundances, including recent measurements of OH [1,2] suggest that the mantle source of at least the OH-analyzed glasses have a water abundance of ~700 ppm - comparable to that of Earth's upper mantle. More recently, [3] showed that the abundance of OH and other volatiles measured in these glasses is positively correlated with trace element abundances, which is expected since water is incompatible in a magma. Volatile enrichment in a deep mantle source would lower the melting temperature and provide the thrust for magma ascent through 500 km of mantle and crust [4]. We are exploring the idea that such basin-related lunar pyroclastic volcanism may represent the last phase of basaltic volcanism in a given region. Remote sensing studies have shown volcanic glasses are fairly common, and often found along the perimeter of mare-filled basins [5]. Recent modeling of the stresses related to the basin-forming process [6,7] show that basin margins provide the ideal conduit for low-volume lunar pyroclastic volcanism (compared with the high output of mare volcanism). Schrödinger's basin floor is largely composed of a compositionally uniform impact breccia. The exceptions are two distinct and

  3. Degrees of freedom in discrete geometry

    CERN Document Server

    Ariwahjoedi, Seramika; Rovelli, Carlo; Zen, Freddy P

    2016-01-01

    Following recent developments in discrete gravity, we study geometrical variables (angles and forms) of simplices in the discrete geometry point of view. Some of our relatively new results include: new ways of writing a set of simplices using vectorial (differential form) and coordinate-free pictures, and a consistent procedure to couple particles of space, together with a method to calculate the degrees of freedom of the system of 'quanta' of space in the classical framework.

  4. The Magnetotail at Lunar Distance

    Science.gov (United States)

    Sibeck, D. G.

    2015-12-01

    This presentation reviews some of the single-point observations of the magnetotail at lunar distances made by ALSEP, Explorer 33, 35, ISEE-3, and Geotail that form the framework for interpreting more recent dual-spacecraft ARTEMIS observations. Earth's distant magnetotail flaps, twists, and flattens in response to variations in the solar wind flow direction and interplanetary magnetic field (IMF) orientation. It may even disappear leaving nothing more than a wake during strongly northward IMF orientations. Standing slow mode expansion fans provide for a gradual transition between magnetotail lobe and magnetosheath plasma and magnetic field parameters. The distant neutral line may at times reside at lunar distances, creating jets of sunward-streaming plasma within the cislunar plasma sheet and layers of streaming energetic particles on its boundaries. Reconnection at near-Earth neutral lines releases antisunward-moving plasmoids that transit lunar distances, briefly expanding the diameter of the plasma sheet and magnetotail. Taken as a whole, the distant magnetotail is a fascinating plasma laboratory and a region of great important to the magnetosphere.

  5. Lunar Applications in Reconfigurable Computing

    Science.gov (United States)

    Somervill, Kevin

    2008-01-01

    NASA s Constellation Program is developing a lunar surface outpost in which reconfigurable computing will play a significant role. Reconfigurable systems provide a number of benefits over conventional software-based implementations including performance and power efficiency, while the use of standardized reconfigurable hardware provides opportunities to reduce logistical overhead. The current vision for the lunar surface architecture includes habitation, mobility, and communications systems, each of which greatly benefit from reconfigurable hardware in applications including video processing, natural feature recognition, data formatting, IP offload processing, and embedded control systems. In deploying reprogrammable hardware, considerations similar to those of software systems must be managed. There needs to be a mechanism for discovery enabling applications to locate and utilize the available resources. Also, application interfaces are needed to provide for both configuring the resources as well as transferring data between the application and the reconfigurable hardware. Each of these topics are explored in the context of deploying reconfigurable resources as an integral aspect of the lunar exploration architecture.

  6. Magnetic beneficiation of lunar soils

    Science.gov (United States)

    Mckay, D. S; Oder, R. R.; Graf, J.; Taylor, L. A.

    1992-01-01

    We will present a review of recent laboratory results obtained in dry magnetic separation of one gram samples of the minus 1 mm size fraction of five lunar soils of widely differing maturities. Two highland soils were investigated as potential sources of low iron content feed stocks for space manufacture of metals, including aluminum, silicon, and calcium. Pure anorthite was separated from the diamagnetic fraction of immature highland regolith. Three high titanium mare soils were investigated as potential sources of ilmenite for production of hydrogen and for recovery of He-3. Ilmenite and pyroxene were separated from the paramagnetic fractions of the mare basalts. Agglutinates and other fused soil components containing metallic iron were separated from the strongly magnetic fractions of all soils. We will present conceptual magnetic separation flow sheets developed from the laboratory data and designed for production of anorthite from highland soils and for production of ilmenite from mare soils. Using these flow sheets, we will discuss problems and opportunities associated with the magnetic separation of lunar soils. Separation of high-grade anorthite or other diamagnetic components at moderately high recovery can be achieved in processing immature highland soils. Further, while magnet weight is always an issue in magnetic separation technology, recent developments in both low temperature and high temperature superconductivity present unusual opportunities for magnet design specific to the lunar environment.

  7. Lunar Landing Operational Risk Model

    Science.gov (United States)

    Mattenberger, Chris; Putney, Blake; Rust, Randy; Derkowski, Brian

    2010-01-01

    Characterizing the risk of spacecraft goes beyond simply modeling equipment reliability. Some portions of the mission require complex interactions between system elements that can lead to failure without an actual hardware fault. Landing risk is currently the least characterized aspect of the Altair lunar lander and appears to result from complex temporal interactions between pilot, sensors, surface characteristics and vehicle capabilities rather than hardware failures. The Lunar Landing Operational Risk Model (LLORM) seeks to provide rapid and flexible quantitative insight into the risks driving the landing event and to gauge sensitivities of the vehicle to changes in system configuration and mission operations. The LLORM takes a Monte Carlo based approach to estimate the operational risk of the Lunar Landing Event and calculates estimates of the risk of Loss of Mission (LOM) - Abort Required and is Successful, Loss of Crew (LOC) - Vehicle Crashes or Cannot Reach Orbit, and Success. The LLORM is meant to be used during the conceptual design phase to inform decision makers transparently of the reliability impacts of design decisions, to identify areas of the design which may require additional robustness, and to aid in the development and flow-down of requirements.

  8. Probing General Relativity and New Physics with Lunar Laser Ranging

    Science.gov (United States)

    Dell'Agnello, S.; Maiello, M.; Currie, D. G.; Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G. O.; Intaglietta, N.; Lops, C.; Garattini, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M.; Vittori, R.; Bianco, G.; Coradini, A.; Dionisio, C.; March, R.; Bellettini, G.; Tauraso, R.; Chandler, J.

    2012-11-01

    primary goal of these innovative tools is to provide critical design and diagnostic capabilities for Satellite Laser Ranging (SLR) to Galileo and other GNSS (Global Navigation Satellite System) constellations. Implementation of new retroreflector designs being studied will help to improve GNSS orbits, which will then increase the accuracy, stability, and distribution of the International Terrestrial Reference Frame (ITRF) [4], to provide better definition of the geocenter (origin) and the scale (length unit). The SCF is also actively used to develop, validate and optimize the second generation LLR arrays for precision gravity and lunar science measurements to be performed with robotic missions of the International Lunar Network in which NASA and ASI participate (ILN). The capability will allow us to optimize the design of GNSS laser retroreflector payloads to maximize ranging efficiency, to improve signal-to-noise conditions in daylight and to provide pre-launch validation of retroreflector performance under laboratory-simulated space conditions. For the MAGIA lunar orbiter Phase A study funded by ASI (Dell'Agnello et al., 2010 [14]), we studied fundamental physics and absolute positioning metrology experiments, to improve test of the gravitational redshift in the Earth-Moon system predicted by General Relativity and a precursor test of our second generation LLR payload.

  9. Probing General Relativity and New Physics with Lunar Laser Ranging

    Energy Technology Data Exchange (ETDEWEB)

    Dell' Agnello, S. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Maiello, M., E-mail: mauro.maiello@lnf.infn.it [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Currie, D.G. [University of Maryland (UMD), College Park, MD (United States); Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G.O.; Intaglietta, N.; Lops, C.; Garattini, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Vittori, R. [Aeronautica Militare Italiana (AMI), Rome (Italy); Agenzia Spaziale Italiana (ASI), Rome (Italy); Bianco, G. [ASI-Centro di Geodesia Spaziale, Matera (Italy); Coradini, A. [INAF-Istituto di Fisica dello Spazio Interplanetario (IFSI), Via Fosso del Cavaliere 100, 00133 Rome (Italy); Dionisio, C. [Rheinmetall Italia S.p.A., Via Affile 102, 00131 Rome (Italy); March, R. [INFN-LNF and CNR-Istituto per le Applicazioni del Calcolo (IAC), Viale del Policlinico 137, 00161 Rome (Italy); Bellettini, G. [INFN-LNF and Department of Mathematics, University of Rome ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Rome (Italy); and others

    2012-11-11

    (LLR). The primary goal of these innovative tools is to provide critical design and diagnostic capabilities for Satellite Laser Ranging (SLR) to Galileo and other GNSS (Global Navigation Satellite System) constellations. Implementation of new retroreflector designs being studied will help to improve GNSS orbits, which will then increase the accuracy, stability, and distribution of the International Terrestrial Reference Frame (ITRF) [4], to provide better definition of the geocenter (origin) and the scale (length unit). The SCF is also actively used to develop, validate and optimize the second generation LLR arrays for precision gravity and lunar science measurements to be performed with robotic missions of the International Lunar Network in which NASA and ASI participate (ILN). The capability will allow us to optimize the design of GNSS laser retroreflector payloads to maximize ranging efficiency, to improve signal-to-noise conditions in daylight and to provide pre-launch validation of retroreflector performance under laboratory-simulated space conditions. For the MAGIA lunar orbiter Phase A study funded by ASI (Dell'Agnello et al., 2010 [14]), we studied fundamental physics and absolute positioning metrology experiments, to improve test of the gravitational redshift in the Earth-Moon system predicted by General Relativity and a precursor test of our second generation LLR payload.

  10. ROSAT Observations of Solar Wind Charge Exchange with the Lunar Exosphere

    Science.gov (United States)

    Collier, Michael R.; Snowden, S. L.; Benna, M.; Carter, J. A.; Cravens, T. E.; Hills, H. Kent; Hodges, R. R.; Kuntz, K. D.; Porter, F. Scott; Read, A.; Robertson, I. P.; Sembay, S. F.; Sibeck, D. G.; Stubbs, Timothy J.; Travnicek, P.

    2012-01-01

    We analyze the ROSAT PSPC soft X-ray image of the Moon taken on 29 June 1990 by examining the radial profile of the count rate in three wedges, two wedges (one north and one south) 13-32 degrees off (19 degrees wide) the terminator towards the dark side and one wedge 38 degrees wide centered on the anti-solar direction. The radial profiles of both the north and the south wedges show substantial limb brightening that is absent in the 38 degree wide antisolar wedge. An analysis of the count rate increase associated with the limb brightening shows that its magnitude is consistent with that expected due to solar wind charge exchange (SWCX) with the tenuous lunar atmosphere. Along with Mars, Venus, and Earth, the Moon represents another solar system body at which solar wind charge exchange has been observed. This technique can be used to explore the solar wind-lunar interaction.

  11. Evidence for an early wet Moon from experimental crystallization of the lunar magma ocean

    Science.gov (United States)

    Lin, Yanhao; Tronche, Elodie J.; Steenstra, Edgar S.; van Westrenen, Wim

    2017-01-01

    The Moon is thought to have been covered initially by a deep magma ocean, its gradual solidification leading to the formation of the plagioclase-rich highland crust. We performed a high-pressure, high-temperature experimental study of lunar mineralogical and geochemical evolution during magma ocean solidification that yields constraints on the presence of water in the earliest lunar interior. In the experiments, a deep layer containing both olivine and pyroxene is formed in the first ~50% of crystallization, β-quartz forms towards the end of crystallization, and the last per cent of magma remaining is extremely iron rich. In dry experiments, plagioclase appears after 68 vol.% solidification and yields a floatation crust with a thickness of ~68 km, far above the observed average of 34-43 km based on lunar gravity. The volume of plagioclase formed during crystallization is significantly less in water-bearing experiments. Using the relationship between magma water content and the resulting crustal thickness in the experiments, and considering uncertainties in initial lunar magma ocean depth, we estimate that the Moon may have contained at least 270 to 1,650 ppm water at the time of magma ocean crystallization, suggesting the Earth-Moon system was water-rich from the start.

  12. Effect of asymmetric gravity jitter excited slosh waves at liquid-vapor interface under microgravity

    Science.gov (United States)

    Hung, R. J.; Pan, H. L.; Lee, C. C.; Leslie, F. W.

    1992-01-01

    The dynamical behavior of fluids affected by the asymmetric gravity jitter oscillations, in particular the effect of surface tension on partially-filled rotating fluids (cryogenic liquid helium and helium vapor) in a sub-scale Gravity Probe-B Spacecraft propellant dewar tank imposed by time-dependent various directions of background gravity environment have been investigated. Results show that lower frequency gravity jitter imposed on the time-dependent variations of the direction of background gravity induced a greater amplitude of oscillations and a stronger degree of asymmetry in liquid-vapor interface geometry than that made by the higher frequency gravity jitter. Furthermore, the greater the components of background gravity in radial and circumferential directions will provide a greater contribution in driving more to the increasing amplitude and degrees of symmetry of liquid-vapor interface profiles which, in turn, modify the disturbance of moment of inertia and angular momentum of spacecraft.

  13. World gravity standards

    Science.gov (United States)

    Uotila, U. A.

    1978-01-01

    In order to use gravity anomalies in geodetic computations and geophysical interpretations, the observed gravity values from which anomalies are derived should be referred to one consistent world wide system. The International Gravity Standardization Net 1971 was adapted by the International Union of Geodesy and Geophysics at Moscow in 1971, the network was result of extensive cooperation by many organizations and individuals around the world. The network contains more than 1800 stations around the world. The data used in the adjustment included more than 25,000 gravimetry, pendulum and absolute measurements.

  14. Phenomenological Quantum Gravity

    CERN Document Server

    Hossenfelder, Sabine

    2009-01-01

    If the history of science has taught us anything, it's that persistence and creativity makes the once impossible possible. It has long been thought experimental tests of quantum gravity are impossible. But during the last decade, several different approaches have been proposed that allow us to test, if not the fundamental theory of quantum gravity itself, so at least characteristic features this theory can have. For the first time we can probe experimentally domains in which quantum physics and gravity cohabit, in spite of our failure so far to make a convincing marriage of them on a theoretical level.

  15. Report from International Lunar Exploration Working Group (ILEWG) to COSPAR

    Science.gov (United States)

    Foing, Bernard H.

    inputs to future missions, including a gap analysis of needed measurements. Highly resolved global data sets are required. Autonomous landing and hazard avoidance will depend on the best topographic map of the Moon, achievable by combining shared data. - New topics such as life sciences, partial gravity processes on the Moon should be followed in relation to future exploration needs.” http://sci.esa.int/ilewg/ http://sci.esa.int/ilewg/47170-gluc-iceum11-beijing-2010lunar-declaration/ References: [1] 1st International Lunar Workshop, Balsiger H. et al., Editors, European Space Agency, 1994. ESA-SP-1170. [2] 2nd International Lunar Workshop, Kyoto, H. Mizutani, editor, Japan Space Forum Publisher, 1997. [3] 3rd International Lunar Workshop, Moscow 1998, E. Galimov, editor. [4] ICEUM4, ESTEC, 2000, ESA SP-462, B.H. Foing & M. Perry, editors. [5] ICEUM5, Hawaii Nov 2003, Durst S.M. et al, Editors, Vol 108, 1-576 pp, Science and Technology Series, American Astronautical Society, 2004. [6] ICEUM6, Udaipur 2004, Bhandari N., Editor, Journal Earth Sys-tem Science, India, 114, No6, Dec 2005, pp. 573-841. [7] ICEUM7, Toronto Sept 2005, sci.esa.int/ilewg. [8] ICEUM8, Beijing July 2006, Journal of Chinese Society of Astronautics, Vol. 28 Sup., 2007, Ji W., Editor. [9] ICEUM9, Sorrento, Italy, Foing B., Espinasse S., Kosters G., Editors. http://sci.esa.int/iceum9, Dec. 2007), [11] Ehrenfreund, P., Foing, B.H., Cellino, A. Editors, The Moon and Near Earth Objects, ASR Vol 37, 1, 2006. [12] Foing, B.H. et al editors, 'Astronomy and Space Science from the Moon', ASR 14, 6, 1994. [13] Ip W.-H., Foing, B.H., Masson Ph.L., editors, The Moon and Mars, ASR Vol 23, 11, 1999. [14] Foing, B.H. et al, editor, Lunar Exploration, Planetary and Space Science, Vol 50, 14-15, 2002. [15] Foing, B.H., Heather, D. editors, 'Lunar Exploration 2000', ASR Vol 30, Nr 8, 2002. [16] Huntress, W. et al 'The next steps in exploring deep space - A cosmic study by the IAA', Acta Astronautica, Vol 58, Issues 6

  16. Constraints on timing and magnitude of early global expansion of the Moon from topographic features in linear gravity anomaly areas

    Science.gov (United States)

    Sawada, Natsuki; Morota, Tomokatsu; Kato, Shinsuke; Ishihara, Yoshiaki; Hiramatsu, Yoshihiro

    2016-05-01

    Gravity data obtained from the Gravity Recovery and Interior Laboratory have revealed linear gravity anomalies (LGAs) formed by the early global expansion of the Moon and subsequent magma intrusion. In this study, using Lunar Orbiter Laser Altimeter topographic data, we investigated topographic profiles across LGAs to verify that they were formed by extensional tectonics. We found that 17 of the 20 LGAs investigated exhibited a valley structure, suggesting that they were formed by tensile stress. Assuming that these topographic depressions accompanied graben formation, the increase in the lunar radius is estimated to be on the order of several tens of meters. On the other hand, assuming that these topographic depressions accompanied flexure of elastic lithosphere due to the LGA load, the elastic thickness during the LGA formation is estimated as ~10 km. The crater frequencies in the vicinity of LGAs indicate that the peak tectonic activity occurred before the basin-forming epoch.

  17. Cosmic Tsunamis in Modified Gravity: Scalar waves disrupting screening mechanisms

    CERN Document Server

    Hagala, R; Mota, D F

    2016-01-01

    Extending General Relativity by adding extra degrees of freedom is a popular approach to explain the accelerated expansion of the universe and to build high energy completions of the theory of gravity. The presence of such new degrees of freedom is, however, tightly constrained from several observations and experiments that aim to test General Relativity in a wide range of scales. The viability of a given modified theory of gravity therefore strongly depends on the existence of a screening mechanism that suppresses the extra degrees of freedom. We perform simulations, and find that waves propagating in the new degrees of freedom can significantly impact the efficiency of the screening mechanisms, thereby spoiling the viability of modified gravity theories. Specifically, we show that the waves produced can increase the amplitude of the fifth force and the Parametrized Post Newtonian parameters by several orders of magnitude.

  18. Topological Induced Gravity

    CERN Document Server

    Oda, Ichiro

    2016-01-01

    We propose a topological model of induced gravity (pregeometry) where both Newton's coupling constant and the cosmological constant appear as integration constants in solving field equations. The matter sector of a scalar field is also considered, and by solving field equations it is shown that various types of cosmological solutions in the FRW universe can be obtained. A detailed analysis is given of the meaning of the BRST transformations, which make the induced gravity be a topological field theory, by means of the canonical quantization analysis, and the physical reason why such BRST transformations are needed in the present formalism is clarified. Finally, we propose a dynamical mechanism for fixing the Lagrange multiplier fields by following the Higgs mechanism. The present study clearly indicates that the induced gravity can be constructed at the classical level without recourse to quantum fluctuations of matter and suggests an interesting relationship between the induced gravity and the topological qu...

  19. Gravity Data for Minnesota

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (55,907 records) were gathered by various governmental organizations (and academia) using a variety of methods. This data base was received...

  20. Causal Newton Gravity Law

    CERN Document Server

    Zinoviev, Yury M

    2012-01-01

    The equations of the relativistic causal Newton gravity law for the planets of the solar system are studied in the approximation when the Sun rests at the coordinates origin and the planets do not iteract between each other.