Astronomers celebrate a year of new Hubble results

Science.gov (United States)

1995-02-01

to reach the telescope, had indeed passed through helium, and not only that, the helium was of just the right variety to match the established theory. Dr Jakobsen has spent more than 20 years working on this subject. His recent efforts concentrated on seeking out a quasar unobscured by clouds of hydrogen, which block the tell-tale signature of helium. His search drew him to the Space Telescope project and during the telescope's early years in orbit he studied 25 likely quasars and found one promising candidate. Dr Jacobsen then had to wait for the telescope's new optics before he could get the quality of data he needed to prove the existence of helium. "We were looking for a break in the cloud cover, so to speak," the astronomer said. "We had a tantalising glimpse of the quasar with the aberrated telescope but it was only after we fixed it that we could really get a clear answer. One of the first things that we did once we had the corrective optics in place was look at this object and it was exactly as we'd hoped." Getting the Universe to measure up When it comes to studying the expansion of the Universe, however, the telescope has raised morn; questions than answers. By determining how fast the Universe is expanding astronomers will be able to calculate its age and size. It may then become possible to discover what is the ultimate fate of the Universe; will it simply continue to expand until it evaporates? Will the expansion come to a complete stop? Or will the Universe stop expanding, start contracting and end in a "big crunch"? The rate at which the Universe expands is known as the Hubble Constant or H0. To measure this value, astronomers need to calculate how far away a galaxy is and how fast it is moving away from us. The former is difficult to determine because reliable distance indicators, sometimes known as "cosmic yardsticks ", such as variable stars and supernovae, must be found in the galaxies. An international team of astronomers recently used the Hubble

Einstein's Jury The Race to Test Relativity

CERN Document Server

Crelinsten, Jeffrey

2006-01-01

Einstein's Jury is the dramatic story of how astronomers in Germany, England, and America competed to test Einstein's developing theory of relativity. Weaving a rich narrative based on extensive archival research, Jeffrey Crelinsten shows how these early scientific debates shaped cultural attitudes we hold today. The book examines Einstein's theory of general relativity through the eyes of astronomers, many of whom were not convinced of the legitimacy of Einstein's startling breakthrough. These were individuals with international reputations to uphold and benefactors and shareholders to p

ASURV: Astronomical SURVival Statistics

Science.gov (United States)

Feigelson, E. D.; Nelson, P. I.; Isobe, T.; LaValley, M.

2014-06-01

ASURV (Astronomical SURVival Statistics) provides astronomy survival analysis for right- and left-censored data including the maximum-likelihood Kaplan-Meier estimator and several univariate two-sample tests, bivariate correlation measures, and linear regressions. ASURV is written in FORTRAN 77, and is stand-alone and does not call any specialized libraries.

Latin American astronomers and the International Astronomical Union

Science.gov (United States)

Torres-Peimbert, S.

2017-07-01

Selected aspects of the participation of the Latin American astronomers in the International Astronomical Union are presented: Membership, Governing bodies, IAU meetings, and other activities. The Union was founded in 1919 with 7 initial member states, soon to be followed by Brazil. In 1921 Mexico joined, and in 1928 Argentina also formed part of the Union, while Chile joined in 1947. In 1961 Argentina, Brazil, Chile, Mexico and Venezuela were already member countries. At present (October 2016) 72 countries contribute financially to the Union. The Union lists 12,391 professional astronomers as individual members; of those, 692 astronomers work in Latin America and the Caribbean, from 13 member states (Argentina, Bolivia , Brazil, Chile, Colombia, Costa Rica, Cuba, Honduras, Mexico, Panamá, Perú, Uruguay and Venezuela) as well as from Ecuador and Puerto Rico. This group comprises 5.58% of the total membership, a figure somewhat lower than the fraction of the population in the region, which is 8.6% of the world population. Of the Latin American members, 23.4% are women and 76.6% are men; slightly higher than the whole membership of Union, which is of 16.9%. In the governing bodies it can be mentioned that there have been 2 Presidents of the Union (Jorge Sahade and Silvia Torres-Peimbert), 7 VicePresidents (Guillermo Haro, Jorge Sahade, Manuel Peimbert Claudio Anguita, Silvia Torres-Peimbert, Beatriz Barbuy, and Marta G. Rovira). The IAU meetings held in the region, include 2 General Assemblies (the 1991 XXI GA took place in Buenos Aires, Argentina and the 2009 XXVIII GA, in Rio de Janeiro, Brazil), 15 Regional Meetings (in Argentina, Brazil, Chile, Colombia, Mexico, Venezuela and Uruguay), 29 Symposia (in Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru and Mexico), 5 Colloquia (in Argentina and Mexico), 8 International Schools for Young Astronomers (in Argentina, Brazil, Cuba, Honduras and Mexico), and 11 projects sponsored by the Office of Astronomy

Radio Astronomers Develop New Technique for Studying Dark Energy

Science.gov (United States)

2010-07-01

Pioneering observations with the National Science Foundation's giant Robert C. Byrd Green Bank Telescope (GBT) have given astronomers a new tool for mapping large cosmic structures. The new tool promises to provide valuable clues about the nature of the mysterious "dark energy" believed to constitute nearly three-fourths of the mass and energy of the Universe. Dark energy is the label scientists have given to what is causing the Universe to expand at an accelerating rate. While the acceleration was discovered in 1998, its cause remains unknown. Physicists have advanced competing theories to explain the acceleration, and believe the best way to test those theories is to precisely measure large-scale cosmic structures. Sound waves in the matter-energy soup of the extremely early Universe are thought to have left detectable imprints on the large-scale distribution of galaxies in the Universe. The researchers developed a way to measure such imprints by observing the radio emission of hydrogen gas. Their technique, called intensity mapping, when applied to greater areas of the Universe, could reveal how such large-scale structure has changed over the last few billion years, giving insight into which theory of dark energy is the most accurate. "Our project mapped hydrogen gas to greater cosmic distances than ever before, and shows that the techniques we developed can be used to map huge volumes of the Universe in three dimensions and to test the competing theories of dark energy," said Tzu-Ching Chang, of the Academia Sinica in Taiwan and the University of Toronto. To get their results, the researchers used the GBT to study a region of sky that previously had been surveyed in detail in visible light by the Keck II telescope in Hawaii. This optical survey used spectroscopy to map the locations of thousands of galaxies in three dimensions. With the GBT, instead of looking for hydrogen gas in these individual, distant galaxies -- a daunting challenge beyond the technical

Methods in Astronomical Image Processing

Science.gov (United States)

Jörsäter, S.

A Brief Introductory Note History of Astronomical Imaging Astronomical Image Data Images in Various Formats Digitized Image Data Digital Image Data Philosophy of Astronomical Image Processing Properties of Digital Astronomical Images Human Image Processing Astronomical vs. Computer Science Image Processing Basic Tools of Astronomical Image Processing Display Applications Calibration of Intensity Scales Calibration of Length Scales Image Re-shaping Feature Enhancement Noise Suppression Noise and Error Analysis Image Processing Packages: Design of AIPS and MIDAS AIPS MIDAS Reduction of CCD Data Bias Subtraction Clipping Preflash Subtraction Dark Subtraction Flat Fielding Sky Subtraction Extinction Correction Deconvolution Methods Rebinning/Combining Summary and Prospects for the Future

The Practical Astronomer

Science.gov (United States)

Koester, Jack

"The Practical Astronomer" by Thomas Dick, LLD, E.C. & J. Biddle, Philadelphia, 1849, is reviewed. Information on telescope makers and astronomers can be found. Mentioned are: Fraunhofer; John Herschel; Lawson; Dollond; Tulley; W. & S. Jones; and S.W. Burnham.

Low Dimensional Embedding of Climate Data for Radio Astronomical Site Testing in the Colombian Andes

Science.gov (United States)

Chaparro Molano, Germán; Ramírez Suárez, Oscar Leonardo; Restrepo Gaitán, Oscar Alberto; Marcial Martínez Mercado, Alexander

2017-10-01

We set out to evaluate the potential of the Colombian Andes for millimeter-wave astronomical observations. Previous studies for astronomical site testing in this region have suggested that nighttime humidity and cloud cover conditions make most sites unsuitable for professional visible-light observations. Millimeter observations can be done during the day, but require that the precipitable water vapor column above a site stays below ˜10 mm. Due to a lack of direct radiometric or radiosonde measurements, we present a method for correlating climate data from weather stations to sites with a low precipitable water vapor column. We use unsupervised learning techniques to low dimensionally embed climate data (precipitation, rain days, relative humidity, and sunshine duration) in order to group together stations with similar long-term climate behavior. The data were taken over a period of 30 years by 2046 weather stations across the Colombian territory. We find six regions with unusually dry, clear-sky conditions, ranging in elevations from 2200 to 3800 masl. We evaluate the suitability of each region using a quality index derived from a Bayesian probabilistic analysis of the station type and elevation distributions. Two of these regions show a high probability of having an exceptionally low precipitable water vapor column. We compared our results with global precipitable water vapor maps and find a plausible geographical correlation with regions with low water vapor columns (˜10 mm) at an accuracy of ˜20 km. Our methods can be applied to similar data sets taken in other countries as a first step toward astronomical site evaluation.

Astronomers Gain Clues About Fundamental Physics

Science.gov (United States)

2005-12-01

An international team of astronomers has looked at something very big -- a distant galaxy -- to study the behavior of things very small -- atoms and molecules -- to gain vital clues about the fundamental nature of our entire Universe. The team used the National Science Foundation's Robert C. Byrd Green Bank Telescope (GBT) to test whether the laws of nature have changed over vast spans of cosmic time. The Green Bank Telescope The Robert C. Byrd Green Bank Telescope CREDIT: NRAO/AUI/NSF (Click on image for GBT gallery) "The fundamental constants of physics are expected to remain fixed across space and time; that's why they're called constants! Now, however, new theoretical models for the basic structure of matter indicate that they may change. We're testing these predictions." said Nissim Kanekar, an astronomer at the National Radio Astronomy Observatory (NRAO), in Socorro, New Mexico. So far, the scientists' measurements show no change in the constants. "We've put the most stringent limits yet on some changes in these constants, but that's not the end of the story," said Christopher Carilli, another NRAO astronomer. "This is the exciting frontier where astronomy meets particle physics," Carilli explained. The research can help answer fundamental questions about whether the basic components of matter are tiny particles or tiny vibrating strings, how many dimensions the Universe has, and the nature of "dark energy." The astronomers were looking for changes in two quantities: the ratio of the masses of the electron and the proton, and a number physicists call the fine structure constant, a combination of the electron charge, the speed of light and the Planck constant. These values, considered fundamental physical constants, once were "taken as time independent, with values given once and forever" said German particle physicist Christof Wetterich. However, Wetterich explained, "the viewpoint of modern particle theory has changed in recent years," with ideas such as

Astronomical Research Using Virtual Observatories

Directory of Open Access Journals (Sweden)

M Tanaka

2010-01-01

Full Text Available The Virtual Observatory (VO for Astronomy is a framework that empowers astronomical research by providing standard methods to find, access, and utilize astronomical data archives distributed around the world. VO projects in the world have been strenuously developing VO software tools and/or portal systems. Interoperability among VO projects has been achieved with the VO standard protocols defined by the International Virtual Observatory Alliance (IVOA. As a result, VO technologies are now used in obtaining astronomical research results from a huge amount of data. We describe typical examples of astronomical research enabled by the astronomical VO, and describe how the VO technologies are used in the research.

FITSManager: Management of Personal Astronomical Data

Science.gov (United States)

Cui, Chenzhou; Fan, Dongwei; Zhao, Yongheng; Kembhavi, Ajit; He, Boliang; Cao, Zihuang; Li, Jian; Nandrekar, Deoyani

2011-07-01

With the increase of personal storage capacity, it is easy to find hundreds to thousands of FITS files in the personal computer of an astrophysicist. Because Flexible Image Transport System (FITS) is a professional data format initiated by astronomers and used mainly in the small community, data management toolkits for FITS files are very few. Astronomers need a powerful tool to help them manage their local astronomical data. Although Virtual Observatory (VO) is a network oriented astronomical research environment, its applications and related technologies provide useful solutions to enhance the management and utilization of astronomical data hosted in an astronomer's personal computer. FITSManager is such a tool to provide astronomers an efficient management and utilization of their local data, bringing VO to astronomers in a seamless and transparent way. FITSManager provides fruitful functions for FITS file management, like thumbnail, preview, type dependent icons, header keyword indexing and search, collaborated working with other tools and online services, and so on. The development of the FITSManager is an effort to fill the gap between management and analysis of astronomical data.

UKRVO Astronomical WEB Services

Directory of Open Access Journals (Sweden)

Mazhaev, O.E.

2017-01-01

Full Text Available Ukraine Virtual Observatory (UkrVO has been a member of the International Virtual Observatory Alliance (IVOA since 2011. The virtual observatory (VO is not a magic solution to all problems of data storing and processing, but it provides certain standards for building infrastructure of astronomical data center. The astronomical databases help data mining and offer to users an easy access to observation metadata, images within celestial sphere and results of image processing. The astronomical web services (AWS of UkrVO give to users handy tools for data selection from large astronomical catalogues for a relatively small region of interest in the sky. Examples of the AWS usage are showed.

Test-particle motion in the nonsymmetric gravitation theory

International Nuclear Information System (INIS)

Moffat, J.W.

1987-01-01

A derivation of the motion of test particles in the nonsymmetric gravitational theory (NGT) is given using the field equations in the presence of matter. The motion of the particle is governed by the Christoffel symbols, which are formed from the symmetric part of the fundamental tensor g/sub μ//sub ν/, as well as by a tensorial piece determined by the skew part of the contracted curvature tensor R/sub μ//sub ν/. Given the energy-momentum tensor for a perfect fluid and the definition of a test particle in the NGT, the equations of motion follow from the conservation laws. The tensorial piece in the equations of motion describes a new force in nature that acts on the conserved charge in a body. Particles that carry this new charge do not follow geodesic world lines in the NGT, whereas photons do satisfy geodesic equations of motion and the equivalence principle of general relativity. Astronomical predictions, based on the exact static, spherically symmetric solution of the field equations in a vacuum and the test-particle equations of motion, are derived in detail. The maximally extended coordinates that remove the event-horizon singularities in the static, spherically symmetric solution are presented. It is shown how an inward radially falling test particle can be prevented from forming an event horizon for a value greater than a specified critical value of the source charge. If a test particle does fall through an event horizon, then it must continue to fall until it reaches the singularity at r = 0

Test-particle motion in the nonsymmetric gravitation theory

Science.gov (United States)

Moffat, J. W.

1987-06-01

A derivation of the motion of test particles in the nonsymmetric gravitational theory (NGT) is given using the field equations in the presence of matter. The motion of the particle is governed by the Christoffel symbols, which are formed from the symmetric part of the fundamental tensor gμν, as well as by a tensorial piece determined by the skew part of the contracted curvature tensor Rμν. Given the energy-momentum tensor for a perfect fluid and the definition of a test particle in the NGT, the equations of motion follow from the conservation laws. The tensorial piece in the equations of motion describes a new force in nature that acts on the conserved charge in a body. Particles that carry this new charge do not follow geodesic world lines in the NGT, whereas photons do satisfy geodesic equations of motion and the equivalence principle of general relativity. Astronomical predictions, based on the exact static, spherically symmetric solution of the field equations in a vacuum and the test-particle equations of motion, are derived in detail. The maximally extended coordinates that remove the event-horizon singularities in the static, spherically symmetric solution are presented. It is shown how an inward radially falling test particle can be prevented from forming an event horizon for a value greater than a specified critical value of the source charge. If a test particle does fall through an event horizon, then it must continue to fall until it reaches the singularity at r=0.

Astronomical random numbers for quantum foundations experiments

Science.gov (United States)

Leung, Calvin; Brown, Amy; Nguyen, Hien; Friedman, Andrew S.; Kaiser, David I.; Gallicchio, Jason

2018-04-01

Photons from distant astronomical sources can be used as a classical source of randomness to improve fundamental tests of quantum nonlocality, wave-particle duality, and local realism through Bell's inequality and delayed-choice quantum eraser tests inspired by Wheeler's cosmic-scale Mach-Zehnder interferometer gedanken experiment. Such sources of random numbers may also be useful for information-theoretic applications such as key distribution for quantum cryptography. Building on the design of an astronomical random number generator developed for the recent cosmic Bell experiment [Handsteiner et al. Phys. Rev. Lett. 118, 060401 (2017), 10.1103/PhysRevLett.118.060401], in this paper we report on the design and characterization of a device that, with 20-nanosecond latency, outputs a bit based on whether the wavelength of an incoming photon is greater than or less than ≈700 nm. Using the one-meter telescope at the Jet Propulsion Laboratory Table Mountain Observatory, we generated random bits from astronomical photons in both color channels from 50 stars of varying color and magnitude, and from 12 quasars with redshifts up to z =3.9 . With stars, we achieved bit rates of ˜1 ×106Hz/m 2 , limited by saturation of our single-photon detectors, and with quasars of magnitudes between 12.9 and 16, we achieved rates between ˜102 and 2 ×103Hz /m2 . For bright quasars, the resulting bitstreams exhibit sufficiently low amounts of statistical predictability as quantified by the mutual information. In addition, a sufficiently high fraction of bits generated are of true astronomical origin in order to address both the locality and freedom-of-choice loopholes when used to set the measurement settings in a test of the Bell-CHSH inequality.

Le Verrier magnificent and detestable astronomer

CERN Document Server

Lequeux, James

2013-01-01

Le Verrier was a superb scientist. His discovery of Neptune in 1846 made him the most famous astronomer of his time. He produced a complete theory of the motions of the planets which served as a basis for planetary ephemeris for a full century. Doing this, he discovered an anomaly in the motion of Mercury which later became the first proof of General Relativity. He also founded European meteorology. However his arrogance and bad temper created many enemies, and he was even fired from his position of Director of the Paris Observatory.

Astronomical Heritage in the National Culture

Science.gov (United States)

Harutyunian, H. A.; Mickaelian, A. M.; Parsamian, E. S.

2014-10-01

The book contains Proceedings of the Archaeoastronomical Meeting "Astronomical Heritage in the National Culture" Dedicated to Anania Shirakatsi's 1400th Anniversary and XI Annual Meeting of the Armenian Astronomical Society. It consists of 3 main sections: "Astronomical Heritage", "Anania Shirakatsi" and "Modern Astronomy", as well as Literature about Anania Shirakatsi is included. The book may be interesting for astronomers, historians, archaeologists, linguists, students and other readers.

Explanatory supplement to the astronomical almanac

CERN Document Server

Urban, Sean E

2013-01-01

The Explanatory Supplement to the Astronomical Almanac offers explanatory material, supplemental information and detailed descriptions of the computational models and algorithms used to produce The Astronomical Almanac, which is an annual publication prepared jointly by the US Naval Observatory and Her Majesty's Nautical Almanac Office in the UK. Like The Astronomical Almanac, The Explanatory Supplement provides detailed coverage of modern positional astronomy. Chapters are devoted to the celestial and terrestrial reference frames, orbital ephemerides, precession, nutation, Earth rotation, and coordinate transformations. These topics have undergone substantial revisions since the last edition was published. Astronomical positions are intertwined with timescales and relativity in The Astronomical Almanac, so related chapters are provided in The Explanatory Supplement. The Astronomical Almanac also includes information on lunar and solar eclipses, physical ephemerides of solar system bodies, and calendars, so T...

Tot Graeci Tot Sententiae: Astronomical Perspective Multiplicity in Ancient Greece

Science.gov (United States)

Longo, O.

2011-06-01

Ancient Greece was made of a multiplicity of thinking heads, in an atmosphere of (relative) freedom of opinions, in every field of knowledge. then we should not wonder if many astronomical and cosmological theories, survived until our 17th century, had already been formulated by different philosophers and in different regions, cities and periods of Greek history. Geocentric and heliocentric theories, as well as an atomistic theory of an infinite universe (with infinite worlds), could survive without crashing with one another. In the same time, religious opinions regarding the planets and Sun as a series of gods were present, however not on a scientific ground.

New discoveries on astronomical orientation of Inca site in Ollantaytambo, Peru

Directory of Open Access Journals (Sweden)

Karolína Hanzalová

2015-12-01

Full Text Available This paper deals with astronomical orientation of Incas objects in Ollantaytambo, which is located about 35 km southeast from Machu Picchu, about 40 km northwest from Cusco, and lies in the Urubamba valley. Everybody writing about Ollantaytambo, shoud read Protzen. (1  He devoted his monograph to description and interpretation of that locality. Book of Salazar and Salazar (2 deals, among others, with the orientation of objects in Ollantaytambo with respect to the cardinal direction. Zawaski and Malville (3 documented astronomical context of major monuments of nine sites in Peru, including Ollantaytambo. We tested astronomical orientation in these places and confirm or disprove hypothesis about purpose of Incas objects. For assessment orientation of objects we used our measurements and also satellite images on Google Earth and digital elevation model from ASTER. The satellite images were used to estimate the astronomical-solar-solstice orientation, together with terrestrial images from Salazar and Salazar (2. The digital elevation model is useful in the mountains, where we need the actual horizon for a calculation of sunset and sunrise on specific days (solstices, which were for Incas people very important. We tested which astronomical phenomenon is connected with objects in Ollantaytambo. First, we focused on Temple of the Sun, also known the Wall of six monoliths.  We tested winter solstice sunrise and the rides of the Pleiades for the epochs 2000, 1500 and 1000 A.D. According with our results the Temple isn´t connected neither with winter solstice sunrise nor with the Pleiades. Then we tested also winter solstice sunset. We tried to use the line from an observation point near ruins of the Temple of Sun, to west-north, in direction to sunset. The astronomical azimuth from this point was about 5° less then we need. From this results we found, that is possible to find another observation point. By Salazar and Salazar (2 we found observation

Astronomical Ecosystems

Science.gov (United States)

Neuenschwander, D. E.; Finkenbinder, L. R.

2004-05-01

Just as quetzals and jaguars require specific ecological habitats to survive, so too must planets occupy a tightly constrained astronomical habitat to support life as we know it. With this theme in mind we relate the transferable features of our elementary astronomy course, "The Astronomical Basis of Life on Earth." Over the last five years, in a team-taught course that features a spring break field trip to Costa Rica, we have introduced astronomy through "astronomical ecosystems," emphasizing astronomical constraints on the prospects for life on Earth. Life requires energy, chemical elements, and long timescales, and we emphasize how cosmological, astrophysical, and geological realities, through stabilities and catastrophes, create and eliminate niches for biological life. The linkage between astronomy and biology gets immediate and personal: for example, studies in solar energy production are followed by hikes in the forest to examine the light-gathering strategies of photosynthetic organisms; a lesson on tides is conducted while standing up to our necks in one on a Pacific beach. Further linkages between astronomy and the human timescale concerns of biological diversity, cultural diversity, and environmental sustainability are natural and direct. Our experience of teaching "astronomy as habitat" strongly influences our "Astronomy 101" course in Oklahoma as well. This "inverted astrobiology" seems to transform our student's outlook, from the universe being something "out there" into something "we're in!" We thank the SNU Science Alumni support group "The Catalysts," and the SNU Quetzal Education and Research Center, San Gerardo de Dota, Costa Rica, for their support.

Super resolution for astronomical observations

Science.gov (United States)

Li, Zhan; Peng, Qingyu; Bhanu, Bir; Zhang, Qingfeng; He, Haifeng

2018-05-01

In order to obtain detailed information from multiple telescope observations a general blind super-resolution (SR) reconstruction approach for astronomical images is proposed in this paper. A pixel-reliability-based SR reconstruction algorithm is described and implemented, where the developed process incorporates flat field correction, automatic star searching and centering, iterative star matching, and sub-pixel image registration. Images captured by the 1-m telescope at Yunnan Observatory are used to test the proposed technique. The results of these experiments indicate that, following SR reconstruction, faint stars are more distinct, bright stars have sharper profiles, and the backgrounds have higher details; thus these results benefit from the high-precision star centering and image registration provided by the developed method. Application of the proposed approach not only provides more opportunities for new discoveries from astronomical image sequences, but will also contribute to enhancing the capabilities of most spatial or ground-based telescopes.

Choosing and using astronomical eyepieces

CERN Document Server

Paolini, William

2013-01-01

This valuable reference fills a number of needs in the field of astronomical eyepieces, including that of a buyer's guide, observer's field guide and technical desk reference. It documents the past market for eyepieces and its evolution right up to the present day. In addition to appealing to practical astronomers - and potentially saving them money - it is useful both as a historical reference and as a detailed review of the current market place for this bustling astronomical consumer product. What distinguishes this book from other publications on astronomy is the involvement of observers from all aspects of the astronomical community, and also the major manufacturers of equipment. It not only catalogs the technical aspects of the many modern eyepieces but also documents amateur observer reactions and impressions of their utility over the years, using many different eyepieces. Eyepieces are the most talked-about accessories and collectible items available to the amateur astronomer. No other item of equi...

Korean Astronomical Calendar, Chiljeongsan

Science.gov (United States)

Lee, Eun Hee

In fifteenth century Korea, there was a grand project for the astronomical calendar and instrument making by the order of King Sejong 世宗 (1418-1450). During this period, many astronomical and calendrical books including Islamic sources in Chinese versions were imported from Ming 明 China, and corrected and researched by the court astronomers of Joseon 朝鮮 (1392-1910). Moreover, the astronomers and technicians of Korea frequently visited China to study astronomy and instrument making, and they brought back useful information in the form of new published books or specifications of instruments. As a result, a royal observatory equipped with 15 types of instrument was completed in 1438. Two types of calendar, Chiljeongsan Naepyeon 七政算內篇 and Chiljeongsan Oepyeon 七政算外篇, based on the Chinese and Islamic calendar systems, respectively, were published in 1444 with a number of calendrical editions such as corrections and example supplements (假令) including calculation methods and results for solar and lunar eclipses.

Theory testing using case studies

DEFF Research Database (Denmark)

Dissing Sørensen, Pernille; Løkke Nielsen, Ann-Kristina

2006-01-01

on the strengths of theory-testing case studies. We specify research paths associated with theory testing in case studies and present a coherent argument for the logic of theoretical development and refinement using case studies. We emphasize different uses of rival explanations and their implications for research...... design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive......Case studies may have different research goals. One such goal is the testing of small-scale and middle-range theories. Theory testing refers to the critical examination, observation, and evaluation of the 'why' and 'how' of a specified phenomenon in a particular setting. In this paper, we focus...

New Life for Astronomical Instruments of the Past at the Astronomical Observatory of Taras Shevchenko

Science.gov (United States)

Kazantseva, Liliya

2012-09-01

Astronomical instruments of the past are certainly valuable artifacts of the history of science and education. Like other collections of scientific equipment, they also demonstrate i) development of scientific and technical ideas, ii) technological features of the historical period, iii) professional features of artists or companies -- manufacturers, and iv) national and local specificity of production. However, astronomical instruments are also devices made for observations of rare phenomena -- solar eclipses, transits of planets of the solar disk, etc. Instruments used to study these rare events were very different for each event, since the science changed quickly between events. The Astronomical Observatory of Kyiv National Taras Shevchenko University has a collection of tools made by leading European and local shops from the early nineteenth century. These include tools for optically observing the first artificial Earth satellites, photography, chronometry, and meteorology. In addition, it has assembled a library of descriptions of astronomical instruments and makers'price-lists. Of particular interest are the large stationary tools that are still active in their pavilions. Almost every instrument has a long interesting history. Museification of astronomical instruments gives them a second life, expanding educational programs and tracing the development of astronomy in general and scientific institution and region in particular. It would be advisable to first create a regional database of these rare astronomical instruments (which is already being done in Ukraine), then a common global database. By combining all the historical information about astronomical instruments with the advantages of the Internet, you can show the full evolution of an astronomical instrument with all its features. Time is relentless, and much is destroyed, badly kept and thrown in the garbage. We need time to protect, capture, and tell about it.

Astronomical Instrumentation System Markup Language

Science.gov (United States)

Goldbaum, Jesse M.

2016-05-01

The Astronomical Instrumentation System Markup Language (AISML) is an Extensible Markup Language (XML) based file format for maintaining and exchanging information about astronomical instrumentation. The factors behind the need for an AISML are first discussed followed by the reasons why XML was chosen as the format. Next it's shown how XML also provides the framework for a more precise definition of an astronomical instrument and how these instruments can be combined to form an Astronomical Instrumentation System (AIS). AISML files for several instruments as well as one for a sample AIS are provided. The files demonstrate how AISML can be utilized for various tasks from web page generation and programming interface to instrument maintenance and quality management. The advantages of widespread adoption of AISML are discussed.

Amateur Astronomers: Secret Agents of EPO

Science.gov (United States)

Berendsen, M.; White, V.; Devore, E.; Reynolds, M.

2008-06-01

Amateur astronomers prime the public to be more interested, receptive, and excited about space science, missions, and programs. Through recent research and targeted programs, amateur astronomy outreach is being increasingly recognized by professional astronomers, educators, and other amateurs as a valued and important service. The Night Sky Network program, administered by the ASP, is the first nationwide research-based program specifically targeted to support outreach by amateur astronomers. This Network of trained and informed amateur astronomers can provide a stimulating introduction to your EPO programs as Network members share the night sky with families, students, and youth groups.

Analyzing Test-Taking Behavior: Decision Theory Meets Psychometric Theory.

Science.gov (United States)

Budescu, David V; Bo, Yuanchao

2015-12-01

We investigate the implications of penalizing incorrect answers to multiple-choice tests, from the perspective of both test-takers and test-makers. To do so, we use a model that combines a well-known item response theory model with prospect theory (Kahneman and Tversky, Prospect theory: An analysis of decision under risk, Econometrica 47:263-91, 1979). Our results reveal that when test-takers are fully informed of the scoring rule, the use of any penalty has detrimental effects for both test-takers (they are always penalized in excess, particularly those who are risk averse and loss averse) and test-makers (the bias of the estimated scores, as well as the variance and skewness of their distribution, increase as a function of the severity of the penalty).

Different Categories of Astronomical Heritage: Issues and Challenges

Science.gov (United States)

Ruggles, Clive

2012-09-01

Since 2008 the AWHWG has, on behalf of the IAU, been working with UNESCO and its advisory bodies to help identify, safeguard and promote cultural properties relating to astronomy and, where possible, to try to facilitate the eventual nomination of key astronomical heritage sites onto the World Heritage List. Unfortunately, the World Heritage Convention only covers fixed sites (i.e., the tangible immovable heritage of astronomy), and a key question for the UNESCO-IAU Astronomy and World Heritage Initiative (AWHI) is the extent to which the tangible moveable and intangible heritage of astronomy (e.g. moveable instruments; ideas and theories) influence the assessment of the tangible immovable heritage. Clearly, in an ideal world we should be concerned not only with tangible immovable heritage but, to quote the AWHWG's own Terms of Reference, ``to help ensure that cultural properties and artefacts significant in the development of astronomy, together with the intangible heritage of astronomy, are duly studied, protected and maintained, both for the greater benefit of humankind and to the potential benefit of future historical research''. With this in mind, the IAU/INAF symposium on ``Astronomy and its Instruments before and after Galileo'' held in Venice in Sep-Oct 2009 recommended that urgent steps should be taken 1. to sensitise astronomers and the general public, and particularly observatory directors and others with direct influence and control over astronomical resources, to the importance of identifying, protecting and preserving the various material products of astronomical research and discovery that already have, or have significant potential to acquire, universal value; (N.B. National or regional interests and concerns have no relevance in the assessment of ``universal value'', which, by definition, extends beyond cultural boundaries and, by reasonable expectation, down the generations into the future. 2. to identify modes of interconnectivity between

Statistical methods for astronomical data analysis

CERN Document Server

Chattopadhyay, Asis Kumar

2014-01-01

This book introduces “Astrostatistics” as a subject in its own right with rewarding examples, including work by the authors with galaxy and Gamma Ray Burst data to engage the reader. This includes a comprehensive blending of Astrophysics and Statistics. The first chapter’s coverage of preliminary concepts and terminologies for astronomical phenomenon will appeal to both Statistics and Astrophysics readers as helpful context. Statistics concepts covered in the book provide a methodological framework. A unique feature is the inclusion of different possible sources of astronomical data, as well as software packages for converting the raw data into appropriate forms for data analysis. Readers can then use the appropriate statistical packages for their particular data analysis needs. The ideas of statistical inference discussed in the book help readers determine how to apply statistical tests. The authors cover different applications of statistical techniques already developed or specifically introduced for ...

Theory of Test Translation Error

Science.gov (United States)

Solano-Flores, Guillermo; Backhoff, Eduardo; Contreras-Nino, Luis Angel

2009-01-01

In this article, we present a theory of test translation whose intent is to provide the conceptual foundation for effective, systematic work in the process of test translation and test translation review. According to the theory, translation error is multidimensional; it is not simply the consequence of defective translation but an inevitable fact…

Theory Testing Using Case Studies

DEFF Research Database (Denmark)

Møller, Ann-Kristina Løkke; Dissing Sørensen, Pernille

2014-01-01

The appropriateness of case studies as a tool for theory testing is still a controversial issue, and discussions about the weaknesses of such research designs have previously taken precedence over those about its strengths. The purpose of the paper is to examine and revive the approach of theory...... testing using case studies, including the associated research goal, analysis, and generalisability. We argue that research designs for theory testing using case studies differ from theorybuilding case study research designs because different research projects serve different purposes and follow different...... research paths....

New knowledge in determining the astronomical orientation of Incas object in Ollantaytambo, Peru

Science.gov (United States)

Hanzalová, K.; Klokočník, J.; Kostelecký, J.

2014-06-01

This paper deals about astronomical orientation of Incas objects in Ollantaytambo, which is located about 35 km southeast from Machu Picchu, about 40 km northwest from Cusco, and lies in the Urubamba valley. Everybody writing about Ollantaytambo, shoud read Protzen (1993). He devoted his monograph to description and interpretation of that locality. Book of Salazar and Salazar (2005) deals, among others, with the orientation of objects in Ollantaytambo with respect to the cardinal direction. Zawaski and Malville (2007) documented astronomical context of major monuments of nine sites in Peru, including Ollantaytambo. We tested astronomical orientation in these places and confirm or disprove hypothesis about purpose of Incas objects. For assessment orientation of objects we used our measurements and also satellite images on Google Earth and digital elevation model from ASTER. The satellite images used to approximate estimation of astronomical orientation. The digital elevation model is useful in the mountains, where we need the really horizon for a calculation of sunset and sunrise on specific days (solstices), which were for Incas people very important. By Incas is very famous that they worshiped the Sun. According to him they determined when to plant and when to harvest the crop. In this paper we focused on Temple of the Sun, also known the Wall of six monoliths. We tested which astronomical phenomenon is connected with this Temple. First, we tested winter solstice sunrise and the rides of the Pleiades for the epochs 2000, 1500 and 1000 A.D. According with our results the Temple isn't connected neither with winter solstice sunrise nor with the Pleiades. Then we tested also winter solstice sunset. We tried to use the line from an observation point near ruins of the Temple of Sun, to west-north, in direction to sunset. The astronomical azimuth from this point was about 5° less then we need. From this results we found, that is possible to find another observation

New knowledge in determining the astronomical orientation of Incas object in Ollantaytambo, Peru

Directory of Open Access Journals (Sweden)

K. Hanzalová

2014-06-01

Full Text Available This paper deals about astronomical orientation of Incas objects in Ollantaytambo, which is located about 35 km southeast from Machu Picchu, about 40 km northwest from Cusco, and lies in the Urubamba valley. Everybody writing about Ollantaytambo, shoud read Protzen (1993. He devoted his monograph to description and interpretation of that locality. Book of Salazar and Salazar (2005 deals, among others, with the orientation of objects in Ollantaytambo with respect to the cardinal direction. Zawaski and Malville (2007 documented astronomical context of major monuments of nine sites in Peru, including Ollantaytambo. We tested astronomical orientation in these places and confirm or disprove hypothesis about purpose of Incas objects. For assessment orientation of objects we used our measurements and also satellite images on Google Earth and digital elevation model from ASTER. The satellite images used to approximate estimation of astronomical orientation. The digital elevation model is useful in the mountains, where we need the really horizon for a calculation of sunset and sunrise on specific days (solstices, which were for Incas people very important. By Incas is very famous that they worshiped the Sun. According to him they determined when to plant and when to harvest the crop. In this paper we focused on Temple of the Sun, also known the Wall of six monoliths. We tested which astronomical phenomenon is connected with this Temple. First, we tested winter solstice sunrise and the rides of the Pleiades for the epochs 2000, 1500 and 1000 A.D. According with our results the Temple isn't connected neither with winter solstice sunrise nor with the Pleiades. Then we tested also winter solstice sunset. We tried to use the line from an observation point near ruins of the Temple of Sun, to west-north, in direction to sunset. The astronomical azimuth from this point was about 5° less then we need. From this results we found, that is possible to find another

Kinematical Test Theories for Special Relativity

Science.gov (United States)

Lämmerzahl, Claus; Braxmaier, Claus; Dittus, Hansjörg; Müller, Holger; Peters, Achim; Schiller, Stephan

A comparison of certain kinematical test theories for Special Relativity including the Robertson and Mansouri-Sext test theories is presented and the accuracy of the experimental results testing Special Relativity are expressed in terms of the parameters appearing in these test theories. The theoretical results are applied to the most precise experimental results obtained recently for the isotropy of light propagation and the constancy of the speed of light.

The First Astronomical Observatory in Cluj-Napoca

Science.gov (United States)

Szenkovits, Ferenc

2008-09-01

One of the most important cities of Romania is Cluj-Napoca (Kolozsvár, Klausenburg). This is a traditional center of education, with many universities and high schools. From the second half of the 18th century the University of Cluj has its own Astronomical Observatory, serving for didactical activities and scientific researches. The famous astronomer Maximillian Hell was one of those Jesuits who put the base of this Astronomical Observatory. Our purpose is to offer a short history of the beginnings of this Astronomical Observatory.

Storing Astronomical Information on the Romanian Territory

Science.gov (United States)

Stavinschi, M.; Mioc, V.

2004-12-01

Romanian astronomy has a more than 2000-year old tradition, which is, however, little known abroad. The first known archive of astronomical information is the Dacian sanctuary at Sarmizegetusa Regia, erected in the first century AD, having similarities with that of Stonehenge. After a gap of more than 1000 years, more sources of astronomical information become available, mainly records of astronomical events. Monasteries were the safest storage places of these genuine archives. We present a classification of the ways of storing astronomical information, along with characteristic examples.

Testing theories

International Nuclear Information System (INIS)

Casten, R F

2015-01-01

This paper discusses some simple issues that arise in testing models, with a focus on models for low energy nuclear structure. By way of simplified examples, we illustrate some dangers in blind statistical assessments, pointing out especially the need to include theoretical uncertainties, the danger of over-weighting precise or physically redundant experimental results, the need to assess competing theories with independent and physically sensitive observables, and the value of statistical tests properly evaluated. (paper)

Test-particle motion in Einstein's unified field theory. I. General theory and application to neutral test particles

International Nuclear Information System (INIS)

Johnson, C.R.

1985-01-01

We develop a method for finding the exact equations of structure and motion of multipole test particles in Einstein's unified field theory: the theory of the nonsymmetric field. The method is also applicable to Einstein's gravitational theory. Particles are represented by singularities in the field. The method is covariant at each step of the analysis. We also apply the method and find both in Einstein's unified field theory and in Einstein's gravitational theory the equations of structure and motion of neutral pole-dipole test particles possessing no electromagnetic multipole moments. In the case of Einstein's gravitational theory the results are the well-known equations of structure and motion of a neutral pole-dipole test particle in a given background gravitational field. In the case of Einstein's unified field theory the results are the same, providing we identify a certain symmetric second-rank tensor field appearing in Einstein's theory with the metric and gravitational field. We therefore discover not only the equations of structure and motion of a neutral test particle in Einstein's unified field theory, but we also discover what field in Einstein's theory plays the role of metric and gravitational field

Improving the Determination of Eastern Elongations of Planetary Satellites in the Astronomical Almanac

Science.gov (United States)

Rura, Christopher; Stollberg, Mark

2018-01-01

The Astronomical Almanac is an annual publication of the US Naval Observatory (USNO) and contains a wide variety of astronomical data used by astronomers worldwide as a general reference or for planning observations. Included in this almanac are the times of greatest eastern and northern elongations of the natural satellites of the planets, accurate to 0.1 hour UT. The production code currently used to determine elongation times generates X and Y coordinates for each satellite (16 total) in 5 second intervals. This consequentially caused very large data files, and resulted in the program devoted to determining the elongation times to be computationally intensive. To make this program more efficient, we wrote a Python program to fit a cubic spline to data generated with a 6-minute time step. This resulted in elongation times that were found to agree with those determined from the 5 second data currently used in a large number of cases and was tested for 16 satellites between 2017 and 2019. The accuracy of this program is being tested for the years past 2019 and, if no problems are found, the code will be considered for production of this section of The Astronomical Almanac.

Astronomical Cybersketching

CERN Document Server

Grego, Peter

2009-01-01

Outlines the techniques involved in making observational sketches and more detailed 'scientific' drawings of a wide variety of astronomical subjects using modern digital equipment; primarily PDAs and tablet PCs. This book also discusses about choosing hardware and software

Astronomical Symbolism in Australian Aboriginal Rock Art

Science.gov (United States)

Norris, Ray P.; Hamacher, Duane W.

2011-05-01

Traditional Aboriginal Australian cultures include a significant astronomical component, perpetuated through oral tradition and ceremony. This knowledge has practical navigational and calendrical functions, and sometimes extends to a deep understanding of the motion of objects in the sky. Here we explore whether this astronomical tradition is reflected in the rock art of Aboriginal Australians. We find several plausible examples of depictions of astronomical figures and symbols, and also evidence that astronomical observations were used to set out stone arrangements. However, we recognise that the case is not yet strong enough to make an unequivocal statement, and describe our plans for further research.

The Victorian Amateur Astronomer: Independent Astronomical Research in Britain 1820-1920

Science.gov (United States)

Chapman, Allan

1999-01-01

This is the first book to look in detail at amateur astronomy in Victorian Britain. It deals with the technical issues that were active in Victorian astronomy, and reviews the problems of finance, patronage and the dissemination of scientific ideas. It also examines the relationship between the amateur and professional in Britain. It contains a wealth of previously unpublished biographical and anecdotal material, and an extended bibliography with notes incorporating much new scholarship. In The Victorian Amateur Astronomer, Allan Chapman shows that while on the continent astronomical research was lavishly supported by the state, in Britain such research was paid for out of the pockets of highly educated, wealthy gentlemen the so-called Grand Amateurs . It was these powerful individuals who commissioned the telescopes, built the observatories, ran the learned societies, and often stole discoveries from their state-employed colleagues abroad. In addition to the Grand Amateurs , Victorian Britain also contained many self-taught amateurs. Although they belonged to no learned societies, these people provide a barometer of the popularity of astronomy in that age. In the late 19th century, the comfortable middle classes clergymen, lawyers, physicians and retired military officers took to astronomy as a serious hobby. They formed societies which focused on observation, lectures and discussions, and it was through this medium that women first came to play a significant role in British astronomy. Readership: Undergraduate and postgraduate students studying the history of science or humanities, professional historians of science, engineering and technology, particularly those with an interest in astronomy, the development of astronomical ideas, scientific instrument makers, and amateur astronomers.

The astronomical tables of Giovanni Bianchini

CERN Document Server

Chabas, Jose

2009-01-01

This book describes and analyses, for the first time, the astronomical tables of Giovanni Bianchini of Ferrara (d. after 1469), explains their context, inserts them into an astronomical tradition that began in Toledo, and addresses their diffusion.

Simon Newcomb: America's Unofficial Astronomer Royal

Science.gov (United States)

Graham, John

2007-10-01

Bill Carter and Merri Sue Carter Mantazas; xiii + 213 pp.; ISBN 1-59113-803-5 2006; $26.95 This book introduced me to a commanding figure in American science from the late nineteenth century: Simon Newcomb. Newcomb has been called the nineteenth-century equivalent of Carl Sagan and Albert Einstein. He rose from humble beginnings to be the preeminent American astronomer of his generation. He made basic, far-reaching, and enduring contributions to positional astronomy and planetary dynamics. On the more practical side, he determined a remarkably accurate value for the velocity of light, one within 0.01% of the value accepted today. His work provided an experimental grounding for the special and general theories of relativity to be formulated by Einstein in the coming twentieth century.

The Soviet center of astronomical data

International Nuclear Information System (INIS)

Dluzhnevskaya, O.B.

1982-01-01

On the basis of the current French-Soviet cooperation in science and technology, the Astronomical Council of the U.S.S.R. Academy of Sciences and the Strasbourg Center signed in 1977 an agreement on setting up the Soviet Center of Astronomical Data as its filial branch. The Soviet Center was created on the basis of a computation center at the Zvenigorod station of the Astronomical Council of the U.S.S.R. Academy of Sciences, which had already had considerable experience of working with stellar catalogues. In 1979 the Center was equipped with a EC-1033 computer. In 1978-1979 the Soviet Center of Astronomical Data (C.A.D.) received from Strasbourg 96 of the most important catalogues. By September 1981 the list of catalogues available at the Soviet Center has reached 140 catalogues some of which are described. (Auth.)

Explaining formation of Astronomical Jets using Dynamic Universe Model

Science.gov (United States)

Naga Parameswara Gupta, Satyavarapu

2016-07-01

Astronomical jets are observed from the centres of many Galaxies including our own Milkyway. The formation of such jet is explained using SITA simulations of Dynamic Universe Model. For this purpose the path traced by a test neutron is calculated and depicted using a set up of one densemass of the mass equivalent to mass of Galaxy center, 90 stars with similar masses of stars near Galaxy center, mass equivalents of 23 Globular Cluster groups, 16 Milkyway parts, Andromeda and Triangulum Galaxies at appropriate distances. Five different kinds of theoretical simulations gave positive results The path travelled by this test neutron was found to be an astronomical jet emerging from Galaxy center. This is another result from Dynamic Universe Model. It solves new problems like a. Variable Mass Rocket Trajectory Problem b. Explaining Very long baseline interferometry (VLBI) observations c. Astronomical jets observed from Milkyway Center d. Prediction of Blue shifted Galaxies e. Explaining Pioneer Anomaly f. Prediction of New Horizons satellite trajectory etc. Dynamic Universe Model never reduces to General relativity on any condition. It uses a different type of mathematics based on Newtonian physics. This mathematics used here is simple and straightforward. As there are no differential equations present in Dynamic Universe Model, the set of equations give single solution in x y z Cartesian coordinates for every point mass for every time step

Atlas of Astronomical Discoveries

CERN Document Server

Schilling, Govert

2011-01-01

Four hundred years ago in Middelburg, in the Netherlands, the telescope was invented. The invention unleashed a revolution in the exploration of the universe. Galileo Galilei discovered mountains on the Moon, spots on the Sun, and moons around Jupiter. Christiaan Huygens saw details on Mars and rings around Saturn. William Herschel discovered a new planet and mapped binary stars and nebulae. Other astronomers determined the distances to stars, unraveled the structure of the Milky Way, and discovered the expansion of the universe. And, as telescopes became bigger and more powerful, astronomers delved deeper into the mysteries of the cosmos. In his Atlas of Astronomical Discoveries, astronomy journalist Govert Schilling tells the story of 400 years of telescopic astronomy. He looks at the 100 most important discoveries since the invention of the telescope. In his direct and accessible style, the author takes his readers on an exciting journey encompassing the highlights of four centuries of astronomy. Spectacul...

Care of astronomical telescopes and accessories a manual for the astronomical observer and amateur telescope maker

CERN Document Server

Pepin, M Barlow

2005-01-01

Commercially-made astronomical telescopes are better and less expensive than ever before, and their optical and mechanical performance can be superb. When a good-quality telescope fails to perform as well as it might, the reason is quite probably that it needs a little care and attention! Here is a complete guide for anyone who wants to understand more than just the basics of astronomical telescopes and accessories, and how to maintain them in the peak of condition. The latest on safely adjusting, cleaning, and maintaining your equipment is combined with thoroughly updated methods from the old masters. Here, too, are details of choosing new and used optics and accessories, along with enhancements you can make to extend their versatility and useful lifetime. This book is for you. Really. Looking after an astronomical telescope isn't only for the experts - although there are some things that only an expert should attempt - and every serious amateur astronomer will find invaluable information here, gleaned from ...

Reporting Astronomical Discoveries: Past, Now, and Future

Science.gov (United States)

Yamaoka, Hitoshi; Green, Daniel W. E.; Samus, Nikolai N.; West, Richard

2015-08-01

Many new astronomical objects have been discovered over the years by amateur astronomers, and this continues to be the case. They have traditionally reported them (as have professional astronomers) to the Central Bureau for Astronomical Telegrams (CBAT), which was established in the 19th century. This procedure has worked very well throughout the 20th century, moving under the umbrella of the newly established IAU in 1920. The discoverers have been honored by the formal announcement of their discoveries in the publications of the CBAT.In recent years, some professional research groups have established other ways of announcing their discoveries of explosive objects such as novae and supernovae; some do not now report their discoveries or spectroscopic confirmations of the transients to the CBAT, including often spectroscopic reports of objects posted to the CBAT "Transient Objects Confirmation Page" -- the highly successful TOCP webpage, which assigns official positional designations to new transients posted there by approved, registered users. This leads to a delay in formal announcements of discoveries by amateur astronomers in many cases, as well as inconsistent designations being put into use by individual groups. Amateur astronomers are feeling frustrated about this situation, and they hope that the IAU will help to settle the situation.We have proposed the new IAU commission NC-52, which will treat these phenomena in a continuation of Commission 6, through the CBAT. We hope to continuously support the reporting of the discoveries by amateur astronomers, as well as professional astronomers, who all deserve and desire proper recognition. Our strategy will maintain the firm trust between the amateur and professional astronomers, which is necessary for true collaboration. The plan is for the CBAT to work with collaborators to assure that discoveries posted on the TOCP are promptly designated and announced by the CBAT, even when confirmations are made elsewhere

Statistical test theory for the behavioral sciences

CERN Document Server

de Gruijter, Dato N M

2007-01-01

Since the development of the first intelligence test in the early 20th century, educational and psychological tests have become important measurement techniques to quantify human behavior. Focusing on this ubiquitous yet fruitful area of research, Statistical Test Theory for the Behavioral Sciences provides both a broad overview and a critical survey of assorted testing theories and models used in psychology, education, and other behavioral science fields. Following a logical progression from basic concepts to more advanced topics, the book first explains classical test theory, covering true score, measurement error, and reliability. It then presents generalizability theory, which provides a framework to deal with various aspects of test scores. In addition, the authors discuss the concept of validity in testing, offering a strategy for evidence-based validity. In the two chapters devoted to item response theory (IRT), the book explores item response models, such as the Rasch model, and applications, incl...

Towards a theory of tiered testing.

Science.gov (United States)

Hansson, Sven Ove; Rudén, Christina

2007-06-01

Tiered testing is an essential part of any resource-efficient strategy for the toxicity testing of a large number of chemicals, which is required for instance in the risk management of general (industrial) chemicals, In spite of this, no general theory seems to be available for the combination of single tests into efficient tiered testing systems. A first outline of such a theory is developed. It is argued that chemical, toxicological, and decision-theoretical knowledge should be combined in the construction of such a theory. A decision-theoretical approach for the optimization of test systems is introduced. It is based on expected utility maximization with simplified assumptions covering factual and value-related information that is usually missing in the development of test systems.

An astronomical murder?

Science.gov (United States)

Belenkiy, Ari

2010-04-01

Ari Belenkiy examines the murder of Hypatia of Alexandria, wondering whether problems with astronomical observations and the date of Easter led to her becoming a casualty of fifth-century political intrigue.

Finding Hidden Treasures: Investigations in US Astronomical Plate Archives

Czech Academy of Sciences Publication Activity Database

Hudec, René; Hudec, L.

2013-01-01

Roč. 53, č. 1 (2013), s. 23-26 ISSN 1210-2709 R&D Projects: GA ČR GA205/08/1207 Institutional support: RVO:67985815 Keywords : astronomical data archives * astronomical photography * astronomical photographic archives Subject RIV: BH - Optics, Masers, Lasers

Astronomía en la cultura

Science.gov (United States)

López, A.; Giménez Benitez, S.; Fernández, L.

La Astronomía en la Cultura es el estudio interdisciplinario a nivel global de la astronomía prehistórica, antigua y tradicional, en el marco de su contexto cultural. Esta disciplina abarca cualquier tipo de estudios o líneas de investigación en que se relacione a la astronomía con las ciencias humanas o sociales. En ella se incluyen tanto fuentes escritas, relatos orales como fuentes arqueológicas, abarcando entre otros, los siguientes temas: calendarios, observación práctica, cultos y mitos, representación simbólica de eventos, conceptos y objetos astronómicos, orientación astronómica de tumbas, templos, santuarios y centros urbanos, cosmología tradicional y la aplicación ceremonial de tradiciones astronómicas, la propia historia de la astronomía y la etnoastronomía (Krupp, 1989) (Iwaniszewski, 1994). En nuestro trabajo abordamos la historia y situación actual de esta disciplina, sus métodos y sus relaciones con otras áreas de investigación.

Astronomical Image and Data Analysis

CERN Document Server

Starck, J.-L

2006-01-01

With information and scale as central themes, this comprehensive survey explains how to handle real problems in astronomical data analysis using a modern arsenal of powerful techniques. It treats those innovative methods of image, signal, and data processing that are proving to be both effective and widely relevant. The authors are leaders in this rapidly developing field and draw upon decades of experience. They have been playing leading roles in international projects such as the Virtual Observatory and the Grid. The book addresses not only students and professional astronomers and astrophysicists, but also serious amateur astronomers and specialists in earth observation, medical imaging, and data mining. The coverage includes chapters or appendices on: detection and filtering; image compression; multichannel, multiscale, and catalog data analytical methods; wavelets transforms, Picard iteration, and software tools. This second edition of Starck and Murtagh's highly appreciated reference again deals with to...

The amateur astronomer

CERN Document Server

Moore, Patrick

2006-01-01

Introduces astronomy and amateur observing together. This edition includes photographs and illustrations. The comprehensive appendices provide hints and tips, as well as data for every aspect of amateur astronomy. This work is useful for amateur astronomers

Frameworks for analyzing and testing theories of gravity

International Nuclear Information System (INIS)

Lee, D.L.

1974-01-01

Theoretical frameworks are presented for the analysis and testing of gravitation theories--both metric and nonmetric. For nonmetric theories, the high precision Eotvos--Dicke--Braginskii (EBD) experiments are demonstrated to be powerful tests of their gravitational coupling to electromagnetic interactions. All known nonmetric theories are ruled out to within the precision of the EDB experiments. A new metric theory of gravity is presented that cannot be distinguished from general relativity in all current and planned solar system experiments. However, this theory has very different gravitational-wave properties. Hence, the need for further tests of metric theories beyond the Parametrized Post--Newtonian formalism is pointed out and the importance of the observation of gravitational waves as a tool for testing relativistic gravity in the future is emphasized. A theory-independent formalism delineating the properties of weak, plane gravitational waves in metric theories is set up. General conservation laws that follow from variational principles in metric theories of gravity are investigated. (U.S.)

Observatory Sponsoring Astronomical Image Contest

Science.gov (United States)

2005-05-01

Forget the headphones you saw in the Warner Brothers thriller Contact, as well as the guttural throbs emanating from loudspeakers at the Very Large Array in that 1997 movie. In real life, radio telescopes aren't used for "listening" to anything - just like visible-light telescopes, they are used primarily to make images of astronomical objects. Now, the National Radio Astronomy Observatory (NRAO) wants to encourage astronomers to use radio-telescope data to make truly compelling images, and is offering cash prizes to winners of a new image contest. Radio Galaxy Fornax A Radio Galaxy Fornax A Radio-optical composite image of giant elliptical galaxy NGC 1316, showing the galaxy (center), a smaller companion galaxy being cannibalized by NGC 1316, and the resulting "lobes" (orange) of radio emission caused by jets of particles spewed from the core of the giant galaxy Click on image for more detail and images CREDIT: Fomalont et al., NRAO/AUI/NSF "Astronomy is a very visual science, and our radio telescopes are capable of producing excellent images. We're sponsoring this contest to encourage astronomers to make the extra effort to turn good images into truly spectacular ones," said NRAO Director Fred K.Y. Lo. The contest, offering a grand prize of $1,000, was announced at the American Astronomical Society's meeting in Minneapolis, Minnesota. The image contest is part of a broader NRAO effort to make radio astronomical data and images easily accessible and widely available to scientists, students, teachers, the general public, news media and science-education professionals. That effort includes an expanded image gallery on the observatory's Web site. "We're not only adding new radio-astronomy images to our online gallery, but we're also improving the organization and accessibility of the images," said Mark Adams, head of education and public outreach (EPO) at NRAO. "Our long-term goal is to make the NRAO Image Gallery an international resource for radio astronomy imagery

Infrared Astronomical Satellite (IRAS) Catalogs and Atlases. Explanatory Supplement

Science.gov (United States)

Beichman, C. A. (Editor); Neugebauer, G. (Editor); Habing, H. J. (Editor); Clegg, P. E. (Editor); Chester, T. J. (Editor)

1985-01-01

The Infrared Astronomical Satellite (IRAS) mission is described. An overview of the mission, a description of the satellite and its telescope system, and a discussion of the mission design, requirements, and inflight modifications are given. Data reduction, flight tests, flux reconstruction and calibration, data processing, and the formats of the IRAS catalogs and atlases are also considered.

Astronomical Books and Charts in the Book of Bibliographie Coreenne

Science.gov (United States)

Lee, Ki-Won; Yang, Hong-Jin; Park, Myeong-Gu

2008-06-01

We investigate astronomical materials listed in the book of Bibliographie Coréenne written by Maurice Courant. He classified ancient Korean books into nine Divisions (?) and thirty six Classes (?), and published them as three volumes (ranging from 1894 to 1896) and one supplement (in 1901). In total, 3,821 books including astronomical ones are listed together with information on physical size, possessional place, bibliographical note, and so forth. Although this book is an essential one in the field of Korea bibliography and contains many astronomical materials such as Cheon-Mun-Ryu-Cho ????, Si-Heon-Seo ??????, and Cheon-Sang-Yeol-Cha-Bun-Ya-Ji-Do ????????, it has not been well known to the public nor to astronomical society. Of 3,821 catalogues, we found that about 50 Items (?) are related to astronomy or astrology, and verified that most ! of them are located in the Kyujanggak Royal Library ???. We also found an unknown astronomical chart, Hon-Cheon-Chong-Seong-Yeol-Cha-Bun-Ya-Ji-Do ??????????. Because those astronomical materials are not well known to international astronomical community and there have been few studies on the materials in Korea, we here introduce and review them, particularly with the astronomical viewpoint.

150th Anniversary of the Astronomical Observatory Library of Sciences

Science.gov (United States)

Solntseva, T.

The scientific library of the Astronomical observatory of Kyiv Taras Shevchenko University is one of the oldest ones of such a type in Ukraine. Our Astronomical Observatory and its scientific library will celebrate 150th anniversary of their foundation. 900 volumes of duplicates of Olbers' private library underlay our library. These ones were acquired by Russian Academy of Sciences for Poulkovo observatory in 1841 but according to Struve's order were transmitted to Kyiv Saint Volodymyr University. These books are of great value. There are works edited during Copernicus', Kepler's, Galilei's, Newton's, Descartes' lifetime. Our library contains more than 100000 units of storage - monographs, periodical astronomical editions from the first (Astronomische Nachrichten, Astronomical journal, Monthly Notices etc.), editions of the majority of the astronomical observatories and institutions of the world, unique astronomical atlases and maps

Choosing and using astronomical filters

CERN Document Server

Griffiths, Martin

2014-01-01

As a casual read through any of the major amateur astronomical magazines will demonstrate, there are filters available for all aspects of optical astronomy. This book provides a ready resource on the use of the following filters, among others, for observational astronomy or for imaging: Light pollution filters Planetary filters Solar filters Neutral density filters for Moon observation Deep-sky filters, for such objects as galaxies, nebulae and more Deep-sky objects can be imaged in much greater detail than was possible many years ago. Amateur astronomers can take

Theory of nonparametric tests

CERN Document Server

Dickhaus, Thorsten

2018-01-01

This textbook provides a self-contained presentation of the main concepts and methods of nonparametric statistical testing, with a particular focus on the theoretical foundations of goodness-of-fit tests, rank tests, resampling tests, and projection tests. The substitution principle is employed as a unified approach to the nonparametric test problems discussed. In addition to mathematical theory, it also includes numerous examples and computer implementations. The book is intended for advanced undergraduate, graduate, and postdoc students as well as young researchers. Readers should be familiar with the basic concepts of mathematical statistics typically covered in introductory statistics courses.

Serbian Astronomers in Science Citation Index in the XX Century

Science.gov (United States)

Dimitrijevic, Milan S.

The book is written paralelly in Serbian and English. The presence of works of Serbian astronomers and works in astronomical journals published by other Serbian scientists, in Science Citation Index within the period from 1945 up to the end of 2000, has been analyzed. Also is presented the list of 38 papers which had some influence on the development of astronomy in the twentieth century. A review of the development of astronomy in Serbia in the last century is given as well. Particular attention is payed to the Astronomical Observatory, the principal astronomical institution in Serbia, where it is one of the oldest scientific organizations and the only autonomous astronomical institute. Its past development forms an important part of the history of science and culture in these regions. In the book is also considered and the history of the university teaching of astronomy in Serbia after the second world war. First of all the development of the Chair of Astronomy at the Faculty of Mathematics in Belgrade, but also the teaching of astronomy at University in Novi Sad, Ni and Kragujevac is discussed. In addition to professional Astronomy, well developed in Serbia is also the amateur Astronomy. In the review is first of all included the largest and the oldest organization of amateur-astronomers in Serbia, founded in 1934. Besides, here are the Astronomical Society "Novi Sad", ADNOS and Research Station "Petnica". In Valjevo, within the framework of the Society of researchers "Vladimir Mandic - Manda", there is active also the Astronomical Group. In Kragujevac, on the roof of the Institute of Physics of the Faculty of Sciences, there is the "Belerofont" Observatory. In Ni, at the close of the sixties and the start of the seventies, there was operating a branch of the Astronomical Society "Rudjer Bokovic", while at the Faculty of Philosophy there existed in the period 1976-1980 the "Astro-Geophysical Society". In the year 1996 there was founded Astronomical Society

Astrophysics is easy! an introduction for the amateur astronomer

CERN Document Server

Inglis, Michael

2015-01-01

Astrophysics is often –with some justification – regarded as incomprehensible without the use of higher mathematics. Consequently, many amateur astronomers miss out on some of the most fascinating aspects of the subject. Astrophysics Is Easy! cuts through the difficult mathematics and explains the basics of astrophysics in accessible terms. Using nothing more than plain arithmetic and simple examples, the workings of the universe are outlined in a straightforward yet detailed and easy-to-grasp manner.   The original edition of the book was written over eight years ago, and in that time, advances in observational astronomy have led to new and significant changes to the theories of astrophysics. The new theories will be reflected in both the new and expanded chapters.   A unique aspect of this book is that, for each topic under discussion, an observing list is included so that observers can actually see for themselves the concepts presented –stars of the spectral sequence, nebulae, galaxies, even black ...

Preservation and maintenance of the astronomical sites in Armenia

Science.gov (United States)

Mickaelian, A. M.

2008-01-01

Astronomy in Armenia was popular since ancient times. There are signs of astronomical observations coming from a few thousands years ago. Two ancient observatories, Karahunge and Metzamor are especially well known. Karahunge is the Armenian twin of the Stonehenge and is even older. However, there is no proper attention from the state authorities and efforts are needed for preservation of such historical-astronomical monuments. The Byurakan Astrophysical Observatory (BAO) is the modern famous Armenian observatory founded in 1946 by the outstanding scientist Victor Ambartsumian. It was one of the world astronomical centres in 1950-s to 1970-s, and at present is the largest observatory in the Middle East area. As the ancient astronomical sites, Byurakan also needs a proper attitude from the state authorities and corresponding international organizations to preserve its values and importance for the present and future astronomical activities in the region, including its rich observational archive, telescopes, and human resources. Despite all the difficulties, the Armenian astronomers keep high international level of research and display various activities organizing international meetings and schools, preparing new young generation for the future research. The Armenian Astronomical Society (ArAS) is an affiliated member of EAS. Armenia has its Virtual Observatory project (ArVO) as well. The next Joint European and National Astronomy Meeting (JENAM-2007) will be held in Yerevan, Armenia, in August 2007. There are plans to organize astronomical tours to Armenia for making observations from various sites, including the ancient observatories. The future of astronomy in Armenia strongly depends on all of this activities and the proper attention both from state authorities and society.

Basic Optics for the Astronomical Sciences

CERN Document Server

Breckinridge, James

2012-01-01

This text was written to provide students of astronomy and engineers an understanding of optical science - the study of the generation, propagation, control, and measurement of optical radiation - as it applies to telescopes and instruments for astronomical research in the areas of astrophysics, astrometry, exoplanet characterization, and planetary science. The book provides an overview of the elements of optical design and physical optics within the framework of the needs of the astronomical community.

Information seeking behavior of Greek astronomers

OpenAIRE

Brindesi, Hara; Kapidakis, Sarantos

2011-01-01

This study examines three aspects of information seeking behaviour of astronomers in Greece including a) the importance they place in keeping up- to-date with current developments b) the methods they depend on for keeping up-to-date and c) the information sources they mostly use. We adopted an intradisciplinary approach in order to investigate similarities and differences in information seeking behaviour among astronomers when examining them as groups bearing different characteristics, includ...

Testing strong interaction theories

International Nuclear Information System (INIS)

Ellis, J.

1979-01-01

The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

New astronomical references in two Catalonian late medieval documents.

Science.gov (United States)

Martínez, María José; Marco, Francisco J

2014-01-01

In 2008, after 13 years of preparation, the Generalitat of Catalunya finished the publication of the 10 volumes of the Dietaris de la Generalitat de Catalunya. The Dietaris, as well as a closely related source, the llibre de Jornades 1411/1484 de Jaume Safont, cover the period of 1411 to 1539. In this article, we examine astronomical references contained in these two sources, and place them in their historical context. Our main focus lies on astronomical phenomena that have not previously been published in the astronomical literature. In fact, relatively few astronomical records are accessible in Spanish medieval and early modern history, and our paper intends to fill this gap partially.

Astronomical Books and Charts in the Book of Bibliographie Coreenne

Directory of Open Access Journals (Sweden)

Ki-Won Lee

2008-06-01

Full Text Available We investigate astronomical materials listed in the book of Bibliographie Coreenne written by Maurice Courant. He classified ancient Korean books into nine Divisions (部 and thirty six Classes (類, and published them as three volumes (ranging from 1894 to 1896 and one supplement (in 1901. In total, 3,821 books including astronomical ones are listed together with information on physical size, possessional place, bibliographical note, and so forth. Although this book is an essential one in the field of Korea bibliography and contains many astronomical materials such as Cheon-Mun-Ryu-Cho 天文類抄, Si-Heon-Seo 時憲書, and Cheon-Sang-Yeol-Cha-Bun-Ya-Ji-Do 天象列次分野之圖, it has not been well known to the public nor to astronomical society. Of 3,821 catalogues, we found that about 50 Items (種 are related to astronomy or astrology, and verified that most of them are located in the Kyujanggak Royal Library 奎章閣. We also found an unknown astronomical chart, Hon-Cheon-Chong-Seong-Yeol-Cha-Bun-Ya-Ji-Do 渾天總星列次分野之圖. Because those astronomical materials are not well known to international astronomical community and there have been few studies on the materials in Korea, we here introduce and review them, particularly with the astronomical viewpoint.

Early results from the Infrared Astronomical Satellite

International Nuclear Information System (INIS)

Neugebauer, G.; Beichman, C.A.; Soifer, B.T.

1984-01-01

For 10 months the Infrared Astronomical Satellite (IRAS) provided astronomers with what might be termed their first view of the infrared sky on a clear, dark night. Without IRAS, atmospheric absorption and the thermal emission from both the atmosphere and Earthbound telescopes make the task of the infrared astronomer comparable to what an optical astronomer would face if required to work only on cloudy afternoons. IRAS observations are serving astronomers in the same manner as the photographic plates of the Palomar Observatory Sky Survey; just as the optical survey has been used by all astronomers for over three decades, as a source of quantitative information about the sky and as a roadmap for future observations, the results of IRAS will be studied for years to come. IRAS has demonstrated the power of infrared astronomy from space. Already, from a brief look at a miniscule fraction of the data available, we have learned much about the solar system, about nearby stars, about the Galaxy as a whole and about distant extragalactic systems. Comets are much dustier than previously thought. Solid particles, presumably the remnants of the star-formation process, orbit around Vega and other stars and may provide the raw material for planetary systems. Emission from cool interstellar material has been traced throughout the Galaxy all the way to the galactic poles. Both the clumpiness and breadth of the distribution of this material were previously unsuspected. The far-infrared sky away from the galactic plane has been found to be dominate by spiral galaxies, some of which emit more than 50% and as much as 98% of their energy in the infrared - an exciting and surprising revelation. The IRAS mission is clearly the pathfinder for future mission that, to a large extent, will be devoted to the discoveries revealed by IRAS. 8 figures

Astronomical Observatory of Belgrade from 1924 to 1955

Science.gov (United States)

Radovanac, M.

2014-12-01

History of the Astronomical Observatory in Belgrade, as the presentation is done here, become the field of interest to the author of the present monograph in early 2002. Then, together with Luka C. Popovic, during the Conference "Development of Astronomy among Serbs II" held in early April of that year, he prepared a paper entitled "Astronomska opservatorija tokom Drugog Svetskog rata" (Astronomical Observatory in the Second World War). This paper was based on the archives material concerning the Astronomical Observatory which has been professionally bearing in mind the author's position the subject of his work.

The Mediterranean Plio-Pleistocene: A reference frame for astronomically paced low and high latitude climate changes (Jean Baptiste Lamarck Medal Lecture)

Science.gov (United States)

Lourens, Lucas

2016-04-01

The astronomical theory of climate has revolutionized our understanding of past climate change and the development of highly accurate geologic time scales for the entire Cenozoic. Most of this understanding has started with the construction of high-resolution stable oxygen isotope (18O) records from planktonic and benthic foraminifera of open ocean deep marine sediments explored by the international drilling operations of DSDP, ODP and IODP. These efforts culminated into global ocean isotopic stacked records, which give a clear picture of the evolution of the climate state through time. Fundamental for these reconstructions are the assumptions made between the astronomical forcing and the tuned time series and the accuracy of the astronomical solution. In the past decades, an astronomically calibrated time scale for the Pliocene and Pleistocene of the Mediterranean has been developed, which has become the reference for the standard Geologic Time Scale. Characteristic of the studied marine sediments are the cyclic lithological alternations, reflecting the interference between obliquity and precession-paced low latitude climate variability. These interference patterns allowed to evaluate the accuracy of astronomical solutions and to constrain the dynamical ellipticity of the Earth and tidal dissipation by the Sun and the Moon, which in turn provided the backbone for the widely applied LR04 open ocean benthic isotope stack of the past 5 Myr. So far, the assumed time lags between orbital forcing and the global climate response as reflected in LR04 have not been tested, while these assumptions hark back to SPECMAP, using simple ice sheet models and a limited number of radiometric dates. In addition, LR04 adopted a shorter response time for the smaller ice caps during the Pliocene. Here I present the first benthic 18O record of the Mediterranean reference scale, which strikingly mirrors the LR04. I will use this record to discuss the assumed phase relations and its

Novel Algorithms for Astronomical Plate Analyses

Czech Academy of Sciences Publication Activity Database

Hudec, René; Hudec, L.

2011-01-01

Roč. 32, 1-2 (2011), s. 121-123 ISSN 0250-6335. [Conference on Multiwavelength Variability of Blazars. Guangzhou, 22,09,2010-24,09,2010] R&D Projects: GA ČR GA205/08/1207 Grant - others:GA ČR(CZ) GA102/09/0997; MŠMT(CZ) ME09027 Institutional research plan: CEZ:AV0Z10030501 Keywords : astronomical plates * plate archives archives * astronomical algorithms Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.400, year: 2011

Sky as a bridge: Astronomical interactions in Eurasia through the ages

Science.gov (United States)

Kochhar, Rajesh Kumar

2015-08-01

Since the sky constituted common heritage for the whole humankind, astronomical thoughts, prescriptions, apparatus and tools developed in a particular cultural area were monitored by others and selectively assimilated. The fact that an artificial unit of time, the seven-day week, came to be used in the whole world is a powerful illustration of the world-wide transmission of astronomical ideas.Historical facts here are interpreted in a framework, called Cultural Copernicanism which asserts that no cultural, geographical or ethnic area can be deemed to be a benchmark to be used to evaluate and judge others. This framework manifestly rejects Euro-centrism as well as anti-Euro-centrism. At the same time, astronomy is viewed as a multi-stage intellectual cumulus where each stage builds on the previous one and carries the subject forward.Post-Alexandrian developments brought about a synthesis between classical Greek intellectual tradition and the accomplishments of the still older Egyptian and Mesopotamian civilizations. The Greco-Babylonian inputs in turn vitalized Indian astronomy which along with cosmological ideas, travelled to East Asia (China, Korea, Japan in that order) and Tibet as part of the Buddhist package. Indian astronomical theory was noticed in the area now called the Middle East, but did not significantly influence local developments. The fact that the popular English term algorithm comes from a place name in Central Asia and that Europe designated Indian-origin numerals as Arabic numerals tells us about the role Muslim Cultural Zone has historically played in the intellectual development of Europe.In an earlier era, transmission of astronomical knowledge and ideas in general occurred in an un-self-conscious manner. In relatively recent times, however, considerations of origins, borrowings and priorities were introduced as part of colonial historiography. Thus, in the early 19th century, when Urdu school text books were being prepared under British

Dacic Ancient Astronomical Research in Sarmizegetuza

Directory of Open Access Journals (Sweden)

Emanuel George Oprea

2015-11-01

Full Text Available The actual Romanian territory belongs to Carpatho-Danubian Space and to Ancient Europe. The Ancient European Society was a vast cultural entity based on a theocratic, matriarchal society, peaceful and art creating.Temples of Sarmizegetusa have given rise to several theories over time, proven by historians with the most diverse arguments. The largest complex of temples and sanctuaries was founded in Sarmizegetusa Regia, the Dacian’s main fortress and ancient capital of Dacia in the time of King Decebalus. The mysterious form of settlements has led researchers to the conclusion that the locations were astronomical observation shrines. Among the places of Dacian worship in Orastie Mountains the most impressive is the Great Circular Sanctuary, used to perform some celestial observations, and also as original solar calendar. This paper had the purpose to re-discover the Dacian Civilization and Dacian cosmogony based on the accumulated knowledge upon our country’s past.

An Astronomer In The Classroom: Observatoire de Paris's Partnership Between Teachers and Astronomers

Science.gov (United States)

Doressoundiram, A.; Barban, C.

2006-08-01

The Observatoire de Paris is offering a partnership between teachers and astronomers. The principle is simple: any teacher wishing to undertake a pedagogical project in astronomy, in the classroom or involving the entire school, can request the help of a mentor. An astronomer from the Observatoire de Paris will then follow the teacher's project progress and offer advice and scientific support throughout the school year. The projects may take different forms: construction projects (models, instruments), lectures, posters, exhibitions, etc. The type of assistance offered is as varied as the projects: lecture(s) in class, telephone and e-mail exchanges, visits to the Observatoire; an almost made-to-measure approach that delighted the thirty or so groups that benefited such partnership in the 2005-2006 academic year. And this number is continuously growing. There was a rich variety of projects undertaken, from mounting a show and building a solar clock to visiting a high altitude observatory, or resolving the mystery of Jupiter's great red spot. The Universe and its mysteries fascinate the young (and the not so- young) and provide a multitude of scientific topics that can be exploited in class. Astronomy offers the added advantage of being a multidisciplinary field. Thus, if most projects are generally initiated by a motivated teacher, they are often taken over by teachers in other subjects: Life and Earth Sciences (SVT), history, mathematics, French, and so forth. The project may consist in an astronomy workshop or be part of the school curriculum. Whatever the case, the astronomer's task is not to replace the teacher or the textbooks, but to propose activities or experiments that are easy to implement. Representing the Solar system on a school-yard scale, for instance, is a perfect way to make youngsters realize that the Universe consists mostly of empty space. There is no shortage of topics, and the students' enthusiasm, seldom absent, is the best reward for the

Astronomical Image Compression Techniques Based on ACC and KLT Coder

Directory of Open Access Journals (Sweden)

J. Schindler

2011-01-01

Full Text Available This paper deals with a compression of image data in applications in astronomy. Astronomical images have typical specific properties — high grayscale bit depth, size, noise occurrence and special processing algorithms. They belong to the class of scientific images. Their processing and compression is quite different from the classical approach of multimedia image processing. The database of images from BOOTES (Burst Observer and Optical Transient Exploring System has been chosen as a source of the testing signal. BOOTES is a Czech-Spanish robotic telescope for observing AGN (active galactic nuclei and the optical transient of GRB (gamma ray bursts searching. This paper discusses an approach based on an analysis of statistical properties of image data. A comparison of two irrelevancy reduction methods is presented from a scientific (astrometric and photometric point of view. The first method is based on a statistical approach, using the Karhunen-Loeve transform (KLT with uniform quantization in the spectral domain. The second technique is derived from wavelet decomposition with adaptive selection of used prediction coefficients. Finally, the comparison of three redundancy reduction methods is discussed. Multimedia format JPEG2000 and HCOMPRESS, designed especially for astronomical images, are compared with the new Astronomical Context Coder (ACC coder based on adaptive median regression.

Astronomical Data and Information Visualization

Science.gov (United States)

Goodman, Alyssa A.

2010-01-01

As the size and complexity of data sets increases, the need to "see" them more clearly increases as well. In the past, many scientists saw "fancy" data and information visualization as necessary for "outreach," but not for research. In this talk, I wlll demonstrate, using specific examples, why more and more scientists--not just astronomers--are coming to rely upon the development of new visualization strategies not just to present their data, but to understand it. Principal examples will be drawn from the "Astronomical Medicine" project at Harvard's Initiative in Innovative Computing, and from the "Seamless Astronomy" effort, which is co-sponsored by the VAO (NASA/NSF) and Microsoft Research.

The South African Astronomical Observatory

International Nuclear Information System (INIS)

1989-01-01

The research work discussed in this report covers a wide range, from work on the nearest stars to studies of the distant quasars, and the astronomers who have carried out this work come from universities and observatories spread around the world as well as from South African universities and from the South African Astronomical Observatory (SAAO) staff itself. A characteristic of much of this work has been its collaborative character. SAAO studies in 1989 included: supernovae 1987A; galaxies; ground-based observations of celestial x-ray sources; the Magellanic Clouds; pulsating variables; galactic structure; binary star phenomena; the provision of photometric standards; nebulous matter; stellar astrophysics, and astrometry

Atmospheres in a Test Tube: state of the art at the Astronomical Observatory of Padova.

Science.gov (United States)

Erculiani, M. S.; Claudi, R.; Cocola, L.; Giro, E.; La Rocca, N.; Morosinotto, T.; Poletto, L.; Barbisan, D.; Billi, D.; Bonato, M.; D'Alessandro, M.; Galletta, G.; Meneghini, M.; Trivellin, N.; Cestelli Guidi, M.; Pace, E.; Schierano, D.; Micela, G.

At the Astronomical observatory of Padova we are trying to answer some questions about the detectability of biosignatures in the exoplanetary atmospheres, working in the framework of the project Atmosphere in a Test Tube. In particular we are investigating how the presence of photosynthetic biota living on the surface of a planet orbiting in the HZ of an M type star may modify the atmospheric gas abundances. This can be achieved in laboratory with an environmental simulator called MINI - LISA. The simulator allows to modify the temperature and the pressure inside a test chamber, where a selected population of photosynthetic bacteria is arranged. We'll focalize our experiments on the following bacteria: Acaryochloris marina, Halomicronema hongdechloris, Leptolyngbya sp.1 and Chlorogloeopsis fritschii. The first two bacteria are naturally provided with NIR light metabolizers, like Chl-d and Chl-f, while the last two can develop such pigments if grown in NIR light. The experiment will lead us to obtain useful data to be compared with the ones expected either by the future space missions (JWST, ARIEL) and ground based new instrumentation (SPHERE@VLT; GPI@GEMINI; PCS@E-ELT). In this talk we discuss the layout of the experiment and its state of art.

Explanatory Supplement to the Astronomical Almanac, Third Edition

Science.gov (United States)

Seidelmann, P. Kenneth; Urban, S. E.

2010-01-01

"The Explanatory Supplement to the Astronomical Almanac" (hereafter "The Explanatory Supplement") is a comprehensive reference book on the topic of positional astronomy, covering the theories and algorithms used to produce "The Astronomical Almanac" (AsA), an annual publication produced jointly by the Nautical Almanac Office of the US Naval Observatory (USNO) and Her Majesty's Nautical Almanac Office (HMNAO) of the UK Hydrographic Office. The first edition of The Explanatory Supplement appeared in 1961 and was reprinted with amendments during the 1970s. The second edition was printed in 1992 and reprinted until 2006. Since the second edition, several changes have taken place in positional astronomy regarding reference systems and internationally accepted models, data sets, and computational methods; these have been incorporated into the AsA. Additionally, the data presented in the AsA have been modified over the years, with new tables being added and some being discontinued. Given these changes, a new edition of The Explanatory Supplement is appropriate. The third edition has been in development for the last few years and will be available in 2010. The book is organized similarly to the second (1991) edition, with each chapter written by subject matter experts. Authors from USNO and HMNAO contributed to the majority of the book, but there are authors from Jet Propulsion Laboratory, Technical University of Dresden, National Geospatial-Intelligence Agency, University of Texas Austin, and University of Virginia. This paper will discuss this latest edition of the Explanatory Supplement.

3-Space In-Flow Theory of Gravity: Boreholes, Blackholes and the Fine Structure Constant

Directory of Open Access Journals (Sweden)

Cahill R. T.

2006-04-01

Full Text Available A theory of 3-space explains the phenomenon of gravity as arising from the time-dependence and inhomogeneity of the differential flow of this 3-space. The emergent theory of gravity has two gravitational constants: G - Newton's constant, and a dimensionless constant alpha. Various experiments and astronomical observations have shown that alpha is the fine structure constant ~1/137. Here we analyse the Greenland Ice Shelf and Nevada Test Site borehole g anomalies, and confirm with increased precision this value of alpha. This and other successful tests of this theory of gravity, including the supermassive black holes in globular clusters and galaxies, and the "dark-matter" effect in spiral galaxies, shows the validity of this theory of gravity. This success implies that the non-relativistic Newtonian gravity was fundamentally flawed from the beginning, and that this flaw was inherited by the relativistic General Relativity theory of gravity.

Astronomers gossip about the (cosmic) neighborhood.

Science.gov (United States)

Jayawardhana, R

1994-09-09

The Hague, Netherlands, last month welcomed 2000 astronomers from around the world for the 22nd General Assembly of the International Astronomical Union (IAU). From 15 to 27 August, they participated in symposia and discussions on topics ranging from the down-to-Earth issue of light and radio-frequency pollution to the creation of elements at the farthest reaches of time and space, in the big bang. Some of the most striking news, however, came in new findings from our galaxy and its immediate surroundings.

The Church of San Miniato al Monte, Florence: Astronomical and Astrological Connections

Science.gov (United States)

Shrimplin, V.

2011-06-01

The church of San Miniato al Monte is examined in the context of interest in astrology and astronomy in early Renaissance Florence. Vitruvius emphasised the need for architects to "be acquainted with astronomy and the theory of the heavens" in his famous Ten Books of Architecture and, at San Miniato, astronomical and astrological features are combined in order to link humanity with the celestial or spiritual realm. The particular significance of Pisces and Taurus is explored in relation to Christian symbolism, raising questions about the role of astronomy and astrology in art and architecture.

Astronomical optics

CERN Document Server

Schroeder, Daniel J

1988-01-01

Written by a recognized expert in the field, this clearly presented, well-illustrated book provides both advanced level students and professionals with an authoritative, thorough presentation of the characteristics, including advantages and limitations, of telescopes and spectrographic instruments used by astronomers of today.Key Features* Written by a recognized expert in the field* Provides both advanced level students and professionals with an authoritative, thorough presentation of the characteristics, including advantages and limitations, of telescopes and spectrographic i

Reducing the Requirements and Cost of Astronomical Telescopes

Science.gov (United States)

Smith, W. Scott; Whitakter, Ann F. (Technical Monitor)

2002-01-01

Limits on astronomical telescope apertures are being rapidly approached. These limits result from logistics, increasing complexity, and finally budgetary constraints. In an historical perspective, great strides have been made in the area of aperture, adaptive optics, wavefront sensors, detectors, stellar interferometers and image reconstruction. What will be the next advances? Emerging data analysis techniques based on communication theory holds the promise of yielding more information from observational data based on significant computer post-processing. This paper explores some of the current telescope limitations and ponders the possibilities increasing the yield of scientific data based on the migration computer post-processing techniques to higher dimensions. Some of these processes hold the promise of reducing the requirements on the basic telescope hardware making the next generation of instruments more affordable.

SLAC physicists develop test for string theory

CERN Multimedia

Yajnik, Juhi

2006-01-01

"Under certain conditions, string theory solves many of the questions wracking the minds of physicists, but until recently it had one major flaw - it could not be tested. SLAC (Stanford Linear Accelerator Center) scientists have found a way to test this revolutionary theory, which posits that there are 10 or 11 dimensions in our universe" (1 page)

A novel type of very long baseline astronomical intensity interferometer

Science.gov (United States)

Borra, Ermanno F.

2013-12-01

This article presents a novel type of very long baseline astronomical interferometer that uses the fluctuations, as a function of time, of the intensity measured by a quadratic detector, which is a common type of astronomical detector. The theory on which the technique is based is validated by laboratory experiments. Its outstanding principal advantages comes from the fact that the angular structure of an astronomical object is simply determined from the visibility of the minima of the spectrum of the intensity fluctuations measured by the detector, as a function of the frequency of the fluctuations, while keeping the spacing between mirrors constant. This would allow a simple setup capable of high angular resolutions because it could use an extremely large baseline. Another major interest is that it allows for a more efficient use of telescope time because observations at a single baseline are sufficient, while amplitude and intensity interferometers need several observations at different baselines. The fact that one does not have to move the telescopes would also allow detecting faster time variations because having to move the telescopes sets a lower limit to the time variations that can be detected. The technique uses wave interaction effects and thus has some characteristics in common with intensity interferometry. A disadvantage of the technique, like in intensity interferometry, is that it needs strong sources if observing at high frequencies (e.g. the visible). This is a minor disadvantage in the radio region. At high frequencies, this disadvantage is mitigated by the fact that, like in intensity interferometry, the requirements of the optical quality of the mirrors used are far less severe than in amplitude interferometry so that poor quality large reflectors (e.g. Cherenkov telescopes) can be used in the optical region.

Effectiveness of Amateur Astronomers as Informal Science Educators

Science.gov (United States)

Gibbs, Michael G.; Berendsen, Margaret

2007-01-01

The Astronomical Society of the Pacific (ASP) conducted a national survey of in-service teachers participating in Project ASTRO. The survey results document (1) the value that teachers place on supplemental astronomy education provided by professional and amateur astronomers, and (2) the difference that teachers perceive in the value provided by…

Coronagraph for astronomical imaging and spectrophotometry

Science.gov (United States)

Vilas, Faith; Smith, Bradford A.

1987-01-01

A coronagraph designed to minimize scattered light in astronomical observations caused by the structure of the primary mirror, secondary mirror, and secondary support structure of a Cassegrainian telescope is described. Direct (1:1) and reducing (2.7:1) imaging of astronomical fields are possible. High-quality images are produced. The coronagraph can be used with either a two-dimensional charge-coupled device or photographic film camera. The addition of transmission dispersing optics converts the coronagraph into a low-resolution spectrograph. The instrument is modular and portable for transport to different observatories.

First use of a HyViSI H4RG for Astronomical Observations

Energy Technology Data Exchange (ETDEWEB)

Simms, Lance M.; /SLAC; Figer, Donald F.; Hanold, Brandon J.; Kerr, Daniel J.; /Rochester Imaging Lab.; Gilmore, D.Kirk; Kahn, Steven M.; /SLAC; Tyson, J.Anthony; /UC,

2007-09-25

We present the first astronomical results from a 4K2 Hybrid Visible Silicon PIN array detector (HyViSI) read out with the Teledyne Scientific and Imaging SIDECAR ASIC. These results include observations of astronomical standards and photometric measurements using the 2.1m KPNO telescope. We also report results from a test program in the Rochester Imaging Detector Laboratory (RIDL), including: read noise, dark current, linearity, gain, well depth, quantum efficiency, and substrate voltage effects. Lastly, we highlight results from operation of the detector in window read out mode and discuss its potential role for focusing, image correction, and use as a telescope guide camera.

National Astronomical Observatory of Japan

CERN Document Server

Haubold, Hans J; UN/ESA/NASA Workshop on the International Heliophysical Year 2007 and Basic Space Science, hosted by the National Astronomical Observatory of Japan

2010-01-01

This book represents Volume II of the Proceedings of the UN/ESA/NASA Workshop on the International Heliophysical Year 2007 and Basic Space Science, hosted by the National Astronomical Observatory of Japan, Tokyo, 18 - 22 June, 2007. It covers two programme topics explored in this and past workshops of this nature: (i) non-extensive statistical mechanics as applicable to astrophysics, addressing q-distribution, fractional reaction and diffusion, and the reaction coefficient, as well as the Mittag-Leffler function and (ii) the TRIPOD concept, developed for astronomical telescope facilities. The companion publication, Volume I of the proceedings of this workshop, is a special issue in the journal Earth, Moon, and Planets, Volume 104, Numbers 1-4, April 2009.

Astronomical virtual observatory and the place and role of Bulgarian one

Science.gov (United States)

Petrov, Georgi; Dechev, Momchil; Slavcheva-Mihova, Luba; Duchlev, Peter; Mihov, Bojko; Kochev, Valentin; Bachev, Rumen

2009-07-01

Virtual observatory could be defined as a collection of integrated astronomical data archives and software tools that utilize computer networks to create an environment in which research can be conducted. Several countries have initiated national virtual observatory programs that combine existing databases from ground-based and orbiting observatories, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. As a result, data from all the world's major observatories will be available to all users and to the public. This is significant not only because of the immense volume of astronomical data but also because the data on stars and galaxies has been compiled from observations in a variety of wavelengths-optical, radio, infrared, gamma ray, X-ray and more. In a virtual observatory environment, all of this data is integrated so that it can be synthesized and used in a given study. During the autumn of the 2001 (26.09.2001) six organizations from Europe put the establishment of the Astronomical Virtual Observatory (AVO)-ESO, ESA, Astrogrid, CDS, CNRS, Jodrell Bank (Dolensky et al., 2003). Its aims have been outlined as follows: - To provide comparative analysis of large sets of multiwavelength data; - To reuse data collected by a single source; - To provide uniform access to data; - To make data available to less-advantaged communities; - To be an educational tool. The Virtual observatory includes: - Tools that make it easy to locate and retrieve data from catalogues, archives, and databases worldwide; - Tools for data analysis, simulation, and visualization; - Tools to compare observations with results obtained from models, simulations and theory; - Interoperability: services that can be used regardless of the clients computing platform, operating system and software capabilities; - Access to data in near real-time, archived data and historical data; - Additional information - documentation, user-guides, reports

Thirteenth Joint European and National Astronomical Meeting

CERN Document Server

Iniesta, J C

2006-01-01

The book gathers the invited talks to the XIII JENAM conference, organized this time by the European Astronomical Society (EAS) and the Spanish Astronomical Society (SEA), and hosted by the Instituto de Astrofísica de Andalucía (CSIC). All branches of astrophysics are encompassed from the largest scales and cosmology to the solar system and the Sun, through the galaxies and the stars, including a section on astronomical instrumentation. Very relevant experts from all over the world speak in a single book about the most recent, exciting results from their fields in a way which is useful for both researchers in these fields and colleagues working in other disciplines. The book is accompanied by a CD-ROM including the remaining contributions of the meeting in PDF format, hence opening a wide panorama of what is going on in astrophysics nowadays.

Elizabeth Brown (1830-1899), solar astronomer

Science.gov (United States)

Creese, M.

1998-08-01

Were it not for the fact that she was a woman, Elizabeth Brown might well be thought of as a fairly typical nineteenth-century British amateur astronomer. She has a place, although a relatively modest one, in the distinguished group of people who, with their own fortunes, carried out much of the astronomical research being done in the country at a time before extensive government support was forthcoming for the work.1 Her career in fact follows a pattern common to several of the nineteenth-century men astronomers in that her full productive period came only after she was freed from her primary responsibilities; she did not have to amass the necessary financial resources as did many of the men,2 but she had the time-consuming responsibility, not unusual for a Victorian woman, of caring for a parent through a lengthy old age. Only after her father died at the age of ninety-one, did Elizabeth, then in her early fifties, begin her sixteen years of remarkable public activity in astronomy.

3-Space In-Flow Theory of Gravity: Boreholes, Blackholes and the Fine Structure Constant

Directory of Open Access Journals (Sweden)

Cahill R. T.

2006-04-01

Full Text Available A theory of 3-space explains the phenomenon of gravity as arising from the time-dependence and inhomogeneity of the differential flow of this 3-space. The emergent theory of gravity has two gravitational constants: GN — Newton’s constant, and a dimensionless constant α. Various experiments and astronomical observations have shown that α is the fine structure constant ≈ 1/137. Here we analyse the Greenland Ice Shelf and Nevada Test Site borehole g anomalies, and confirm with increased precision this value of α. This and other successful tests of this theory of gravity, including the supermassive black holes in globular clusters and galaxies, and the “dark-matter” effect in spiral galaxies, shows the validity of this theory of gravity. This success implies that the non-relativistic Newtonian gravity was fundamentally flawed from the beginning, and that this flaw was inherited by the relativistic General Relativity theory of gravity.

The Russian-Ukrainian Observatories Network for the European Astronomical Observatory Route Project

Science.gov (United States)

Andrievsky, S. M.; Bondar, N. I.; Karetnikov, V. G.; Kazantseva, L. V.; Nefedyev, Y. A.; Pinigin, G. I.; Pozhalova, Zh. A.; Rostopchina-Shakhovskay, A. N.; Stepanov, A. V.; Tolbin, S. V.

2011-09-01

In 2004,the Center of UNESCO World Heritage has announced a new initiative "Astronomy & World Heritage" directed for search and preserving of objects,referred to astronomy,its history in a global value,historical and cultural properties. There were defined a strategy of thematic programme "Initiative" and general criteria for selecting of ancient astronomical objects and observatories. In particular, properties that are situated or have significance in relation to celestial objects or astronomical events; representations of sky and/or celestial bodies and astronomical events; observatories and instruments; properties closely connected with the history of astronomy. In 2005-2006,in accordance with the program "Initiative", information about outstanding properties connected with astronomy have been collected.In Ukraine such work was organized by astronomical expert group in Nikolaev Astronomical Observatory. In 2007, Nikolaev observatory was included to the Tentative List of UNESCO under # 5116. Later, in 2008, the network of four astronomical observatories of Ukraine in Kiev,Crimea, Nikolaev and Odessa,considering their high authenticities and integrities,was included to the Tentative List of UNESCO under # 5267 "Astronomical Observatories of Ukraine". In 2008-2009, a new project "Thematic Study" was opened as a successor of "Initiative". It includes all fields of astronomical heritage from earlier prehistory to the Space astronomy (14 themes in total). We present the Ukraine-Russian Observatories network for the "European astronomical observatory Route project". From Russia two observatories are presented: Kazan Observatory and Pulkovo Observatory in the theme "Astronomy from the Renaissance to the mid-twentieth century".The description of astronomical observatories of Ukraine is given in accordance with the project "Thematic study"; the theme "Astronomy from the Renaissance to the mid-twentieth century" - astronomical observatories in Kiev,Nikolaev and Odessa; the

Decoding the mechanisms of Antikythera astronomical device

CERN Document Server

Lin, Jian-Liang

2016-01-01

This book presents a systematic design methodology for decoding the interior structure of the Antikythera mechanism, an astronomical device from ancient Greece. The historical background, surviving evidence and reconstructions of the mechanism are introduced, and the historical development of astronomical achievements and various astronomical instruments are investigated. Pursuing an approach based on the conceptual design of modern mechanisms and bearing in mind the standards of science and technology at the time, all feasible designs of the six lost/incomplete/unclear subsystems are synthesized as illustrated examples, and 48 feasible designs of the complete interior structure are presented. This approach provides not only a logical tool for applying modern mechanical engineering knowledge to the reconstruction of the Antikythera mechanism, but also an innovative research direction for identifying the original structures of the mechanism in the future. In short, the book offers valuable new insights for all...

Assessing difference between classical test theory and item ...

African Journals Online (AJOL)

Assessing difference between classical test theory and item response theory methods in scoring primary four multiple choice objective test items. ... All research participants were ranked on the CTT number correct scores and the corresponding IRT item pattern scores from their performance on the PRISMADAT. Wilcoxon ...

Filling the Astronomical Void - A Visual Medium for a Visual Subject

Science.gov (United States)

Ryan, J.

1996-12-01

Astronomy is fundamentally a visual subject. The modern science of astronomy has at its foundation the ancient art of observing the sky visually. The visual elements of astronomy are arguably the most important. Every person in the entire world is affected by visually-observed astronomical phenomena such as the seasonal variations in daylight. However, misconceptions abound and the average person cannot recognize the simple signs in the sky that point to the direction, the hour and the season. Educators and astronomy popularizers widely lament that astronomy is not appreciated in our society. Yet, there is a remarkable dearth of popular literature for teaching the visual elements of astronomy. This is what I refer to as *the astronomical void.* Typical works use illustrations sparsely, relying most heavily on text-based descriptions of the visual astronomical phenomena. Such works leave significant inferential gaps to the inexperienced reader, who is unequipped for making astronomical observations. Thus, the astronomical void remains unfilled by much of the currently available literature. I therefore propose the introduction of a visually-oriented medium for teaching the visual elements of Astronomy. To this end, I have prepared a series of astronomy "comic strips" that are intended to fill the astronomical void. By giving the illustrations the central place, the comic strip medium permits the depiction of motion and other sequential activity, thus effectively representing astronomical phenomena. In addition to the practical advantages, the comic strip is a "user friendly" medium that is inviting and entertaining to a reader. At the present time, I am distributing a monthly comic strip entitled *Starman*, which appears in the newsletters of over 120 local astronomy organizations and on the web at http://www.cyberdrive.net/ starman. I hope to eventually publish a series of full-length books and believe that astronomical comic strips will help expand the perimeter of

Astronomical publications of Melbourne Observatory

Science.gov (United States)

Andropoulos, Jenny Ioanna

2014-05-01

During the second half of the 19th century and the first half of the 20th century, four well-equipped government observatories were maintained in Australia - in Melbourne, Sydney, Adelaide and Perth. These institutions conducted astronomical observations, often in the course of providing a local time service, and they also collected and collated meteorological data. As well, some of these observatories were involved at times in geodetic surveying, geomagnetic recording, gravity measurements, seismology, tide recording and physical standards, so the term "observatory" was being used in a rather broad sense! Despite the international renown that once applied to Williamstown and Melbourne Observatories, relatively little has been written by modern-day scholars about astronomical activities at these observatories. This research is intended to rectify this situation to some extent by gathering, cataloguing and analysing the published astronomical output of the two Observatories to see what contributions they made to science and society. It also compares their contributions with those of Sydney, Adelaide and Perth Observatories. Overall, Williamstown and Melbourne Observatories produced a prodigious amount of material on astronomy in scientific and technical journals, in reports and in newspapers. The other observatories more or less did likewise, so no observatory of those studied markedly outperformed the others in the long term, especially when account is taken of their relative resourcing in staff and equipment.

AESoP: Astronomical Extinction Spectrophotometer

Science.gov (United States)

Linford, Justin; McGraw, J.; Zimmer, P.; Ackermann, M.; Fitch, J.

2009-01-01

The Earth's atmosphere is a major obstruction to the precision and accuracy of ground-based photometry. The atmosphere removes light from astronomical objects both by absorption and scattering by constituent molecules, aerosols and clouds. These effects can change significantly over short time periods and over modest angles on the sky. To further understand these effects, the UNM Measurement Astrophysics Group has designed, built and recently deployed the Astronomical Extinction Spectrophotometer (AESoP), a 100mm objective grating spectrometer. By monitoring bright stars in sensibly the same direction as a larger photometric telescope is observing, AESoP will measure the wavelength-dependent extinction due to the Earth's atmosphere from 450nm to 900nm on time scales of approximately one minute. The collocated Astronomical LIDAR for Extinction (ALE) provides a high-precision monochromatic extinction measurement at 527nm. Knowing the extinction at a single wavelength allows us to pin the relative spectra generated by AESoP. These extinction spectra can then be integrated over the bandpass of the photometric telescope system to create real time corrections of observations. We present the design and construction of AESoP along with the preliminary results of our first combined observing campaign. This effort is our first step toward breaking the 1% photometry barrier. This project is funded by AFRL Grant FA9451-04-2-0355

Managing distributed software development in the Virtual Astronomical Observatory

Science.gov (United States)

Evans, Janet D.; Plante, Raymond L.; Boneventura, Nina; Busko, Ivo; Cresitello-Dittmar, Mark; D'Abrusco, Raffaele; Doe, Stephen; Ebert, Rick; Laurino, Omar; Pevunova, Olga; Refsdal, Brian; Thomas, Brian

2012-09-01

The U.S. Virtual Astronomical Observatory (VAO) is a product-driven organization that provides new scientific research capabilities to the astronomical community. Software development for the VAO follows a lightweight framework that guides development of science applications and infrastructure. Challenges to be overcome include distributed development teams, part-time efforts, and highly constrained schedules. We describe the process we followed to conquer these challenges while developing Iris, the VAO application for analysis of 1-D astronomical spectral energy distributions (SEDs). Iris was successfully built and released in less than a year with a team distributed across four institutions. The project followed existing International Virtual Observatory Alliance inter-operability standards for spectral data and contributed a SED library as a by-product of the project. We emphasize lessons learned that will be folded into future development efforts. In our experience, a well-defined process that provides guidelines to ensure the project is cohesive and stays on track is key to success. Internal product deliveries with a planned test and feedback loop are critical. Release candidates are measured against use cases established early in the process, and provide the opportunity to assess priorities and make course corrections during development. Also key is the participation of a stakeholder such as a lead scientist who manages the technical questions, advises on priorities, and is actively involved as a lead tester. Finally, frequent scheduled communications (for example a bi-weekly tele-conference) assure issues are resolved quickly and the team is working toward a common vision.

Preserving and Archiving Astronomical Photographic Plates

Science.gov (United States)

Castelaz, M. W.; Cline, J. D.

2005-05-01

Astronomical objects change with time. New observations complement past observations recorded on photographic plates. Analyses of changes provide essential routes to information about an object's formation, constitution and evolution. Preserving a century of photographic plate observations is thus of paramount importance. Plate collections are presently widely dispersed; plates may be stored in poor conditions, and are effectively inaccessible to both researchers and historians. We describe a planned project at Pisgah Astronomical Research Institute to preserve the collections of astronomical plates in the United States by gathering them into a single storage location. Collections will be sorted, cleaned, and cataloged on-line so as to provide access to researchers. Full scientific and historic use of the material then requires the observations themselves to be accessible digitally. The project's goal will be the availability of these data as a unique, fully-maintained scientific and educational resource. The new archive will support trans-disciplinary research such as the chemistry of the Earth's atmosphere, library information science, trends in local weather patterns, and impacts of urbanization on telescope use, while the hand-written observatory logs will be a valuable resource for science historians and biographers.

Astronomers Without Borders: A Global Astronomy Community

Science.gov (United States)

Simmons, M.

2011-10-01

Astronomers Without Borders (AWB) brings together astronomy enthusiasts of all types - amateur astronomers, educators, professionals and "armchair" astronomers for a variety of online and physicalworld programs. The AWB web site provides social networking and a base for online programs that engage people worldwide in astronomy activities that transcend geopolitical and cultural borders. There is universal interest in astronomy, which has been present in all cultures throughout recorded history. Astronomy is also among the most accessible of sciences with the natural laboratory of the sky being available to people worldwide. There are few other interests for which people widely separated geographically can engage in activities involving the same objects. AWB builds on those advantages to bring people together. AWB also provides a platform where projects can reach a global audience. AWB also provides unique opportunities for multidisciplinary collaboration in EPO programs. Several programs including The World at Night, Global Astronomy Month and others will be described along with lessons learned.

The South African astronomical observatory

International Nuclear Information System (INIS)

Feast, M.

1985-01-01

A few examples of the activities of the South African Astronomical Observatory are discussed. This includes the studying of stellar evolution, dust around stars, the determination of distances to galaxies and collaboration with space experiments

The National Astronomical Observatory of Japan and Post-war Japanese Optical Astronomy

Science.gov (United States)

Tajima, Toshiyuki

This paper depicts some aspects of the formative process of the Japanese optical and infrared astronomical community in the post-war period, featuring the transition of the National Astronomical Observatory of Japan(NAOJ). We take up three cases of telescope construction, examining their background and their contribution to the Japanese astronomical community. Through these cases, the characteristics of traditions and cultures of optical and infrared astronomy in Japan are considered. Although the Tokyo Astronomical Observatory (TAO) of the University of Tokyo, the predecessor of NAOJ, was originally founded as an agency for practical astronomical observation such as time and almanac service, it has become an international centre for all types of astrophysical research. Research and development of telescopes and observational instruments have become an important part of the astronomers' practice. Now, however, a number of Japanese universities are planning to have their own large to middle-sized telescopes, and a new style of astronomical research is emerging involving astrophysical studies utilising data acquired from the Virtual Observatory, so there is a distinct possibility that the status of the NAOJ will change even further in the future.

A Brief History of Manchester Astronomical Society

Science.gov (United States)

Kilburn, K. J.

Manchester Astronomical Society celebrated its centenary in September 2003. But that centenary was of a hundred years as the MAS: the history of the society goes back much further, and can be traced directly to that great era of.public awareness of astronomy and amateur interest in Victorian England in the last half of the nineteenth century. Allan Chapman has discussed this period in detail, so the present paper concentrates on the MAS's particular influence on Manchester astronomers and recent work on the history of the society.

Astronomical databases of Nikolaev Observatory

Science.gov (United States)

Protsyuk, Y.; Mazhaev, A.

2008-07-01

Several astronomical databases were created at Nikolaev Observatory during the last years. The databases are built by using MySQL search engine and PHP scripts. They are available on NAO web-site http://www.mao.nikolaev.ua.

Implementation of an Improved Adaptive Testing Theory

Science.gov (United States)

Al-A'ali, Mansoor

2007-01-01

Computer adaptive testing is the study of scoring tests and questions based on assumptions concerning the mathematical relationship between examinees' ability and the examinees' responses. Adaptive student tests, which are based on item response theory (IRT), have many advantages over conventional tests. We use the least square method, a…

Relationships among Classical Test Theory and Item Response Theory Frameworks via Factor Analytic Models

Science.gov (United States)

Kohli, Nidhi; Koran, Jennifer; Henn, Lisa

2015-01-01

There are well-defined theoretical differences between the classical test theory (CTT) and item response theory (IRT) frameworks. It is understood that in the CTT framework, person and item statistics are test- and sample-dependent. This is not the perception with IRT. For this reason, the IRT framework is considered to be theoretically superior…

TPCs in high-energy astronomical polarimetry

International Nuclear Information System (INIS)

Black, J K

2007-01-01

High-energy astrophysics has yet to exploit the unique and important information that polarimetry could provide, largely due to the limited sensitivity of previously available polarimeters. In recent years, numerous efforts have been initiated to develop instruments with the sensitivity required for astronomical polarimetry over the 100 eV to 10 GeV band. Time projection chambers (TPCs), with their high-resolution event imaging capability, are an integral part of some of these efforts. After a brief overview of current astronomical polarimeter development efforts, the role of TPCs will be described in more detail. These include TPCs as photoelectric X-ray polarimeters and TPCs as components of polarizationsensitive Compton and pair-production telescopes

Division B Commission 6: Astronomical Telegrams

Science.gov (United States)

Yamaoka, H.; Green, D. W. E.; Samus, N. N.; Aksnes, K.; Gilmore, A. C.; Nakano, S.; Sphar, T.; Tichá, J.; Williams, G. V.

2016-04-01

IAU Commission 6 ``Astronomical Telegrams'' had a single business meeting during Honolulu General Assembly of the IAU. It took place on Tuesday, 11 August 2015. The meeting was attended by Hitoshi Yamaoka (President), Daniel Green (Director of the Central Bureau for Astronomical Telegrams, CBAT, via Skype), Steven Chesley (JPL), Paul Chodas (JPL), Alan Gilmore (Canterbury University), Shinjiro Kouzuma (Chukyo University), Paolo Mazzali (Co-Chair of the Supernova Working Group), Elena Pian (Scuola Normale Superiore di Pisa), Marion Schmitz (chair IAU Working Group Designations + NED), David Tholen (University of Hawaii), Jana Ticha (Klet Observatory), Milos Tichy (Klet Observatory), Giovanni Valsecchi (INAF\\slash Italy), Gareth Williams (Minor Planet Center). Apologies: Nikolai Samus (General Catalogue of Variable Stars, GCVS).

Astrobiology: An astronomer's perspective

International Nuclear Information System (INIS)

Bergin, Edwin A.

2014-01-01

In this review we explore aspects of the field of astrobiology from an astronomical viewpoint. We therefore focus on the origin of life in the context of planetary formation, with additional emphasis on tracing the most abundant volatile elements, C, H, O, and N that are used by life on Earth. We first explore the history of life on our planet and outline the current state of our knowledge regarding the delivery of the C, H, O, N elements to the Earth. We then discuss how astronomers track the gaseous and solid molecular carriers of these volatiles throughout the process of star and planet formation. It is now clear that the early stages of star formation fosters the creation of water and simple organic molecules with enrichments of heavy isotopes. These molecules are found as ice coatings on the solid materials that represent microscopic beginnings of terrestrial worlds. Based on the meteoritic and cometary record, the process of planet formation, and the local environment, lead to additional increases in organic complexity. The astronomical connections towards this stage are only now being directly made. Although the exact details are uncertain, it is likely that the birth process of star and planets likely leads to terrestrial worlds being born with abundant water and organics on the surface

Astronomical Virtual Observatories Through International Collaboration

Directory of Open Access Journals (Sweden)

Masatoshi Ohishi

2010-03-01

Full Text Available Astronomical Virtual Observatories (VOs are emerging research environment for astronomy, and 16 countries and a region have funded to develop their VOs based on international standard protocols for interoperability. The 16 funded VO projects have established the International Virtual Observatory Alliance (http://www.ivoa.net/ to develop the standard interoperable interfaces such as registry (meta data, data access, query languages, output format (VOTable, data model, application interface, and so on. The IVOA members have constructed each VO environment through the IVOA interfaces. National Astronomical Observatory of Japan (NAOJ started its VO project (Japanese Virtual Observatory - JVO in 2002, and developed its VO system. We have succeeded to interoperate the latest JVO system with other VOs in the USA and Europe since December 2004. Observed data by the Subaru telescope, satellite data taken by the JAXA/ISAS, etc. are connected to the JVO system. Successful interoperation of the JVO system with other VOs means that astronomers in the world will be able to utilize top-level data obtained by these telescopes from anywhere in the world at anytime. System design of the JVO system, experiences during our development including problems of current standard protocols defined in the IVOA, and proposals to resolve these problems in the near future are described.

Astrobiology: An astronomer's perspective

Energy Technology Data Exchange (ETDEWEB)

Bergin, Edwin A. [University of Michigan, Department of Astronomy, 500 Church Street, Ann Arbor, MI 48109 (United States)

2014-12-08

In this review we explore aspects of the field of astrobiology from an astronomical viewpoint. We therefore focus on the origin of life in the context of planetary formation, with additional emphasis on tracing the most abundant volatile elements, C, H, O, and N that are used by life on Earth. We first explore the history of life on our planet and outline the current state of our knowledge regarding the delivery of the C, H, O, N elements to the Earth. We then discuss how astronomers track the gaseous and solid molecular carriers of these volatiles throughout the process of star and planet formation. It is now clear that the early stages of star formation fosters the creation of water and simple organic molecules with enrichments of heavy isotopes. These molecules are found as ice coatings on the solid materials that represent microscopic beginnings of terrestrial worlds. Based on the meteoritic and cometary record, the process of planet formation, and the local environment, lead to additional increases in organic complexity. The astronomical connections towards this stage are only now being directly made. Although the exact details are uncertain, it is likely that the birth process of star and planets likely leads to terrestrial worlds being born with abundant water and organics on the surface.

Testing the causal theory of reference.

Science.gov (United States)

Domaneschi, Filippo; Vignolo, Massimiliano; Di Paola, Simona

2017-04-01

Theories of reference are a crucial research topic in analytic philosophy. Since the publication of Kripke's Naming and Necessity, most philosophers have endorsed the causal/historical theory of reference. The goal of this paper is twofold: (i) to discuss a method for testing experimentally the causal theory of reference for proper names by investigating linguistic usage and (ii) to present the results from two experiments conducted with that method. Data collected in our experiments confirm the causal theory of reference for people proper names and for geographical proper names. A secondary but interesting result is that the semantic domain affects reference assignment: while with people proper names speakers tend to assign the semantic reference, with geographical proper names they are prompted to assign the speaker's reference. Copyright © 2016 Elsevier B.V. All rights reserved.

Lessons from the masters current concepts in astronomical image processing

CERN Document Server

2013-01-01

There are currently thousands of amateur astronomers around the world engaged in astrophotography at increasingly sophisticated levels. Their ranks far outnumber professional astronomers doing the same and their contributions both technically and artistically are the dominant drivers of progress in the field today. This book is a unique collaboration of individuals, all world-renowned in their particular area, and covers in detail each of the major sub-disciplines of astrophotography. This approach offers the reader the greatest opportunity to learn the most current information and the latest techniques directly from the foremost innovators in the field today.   The book as a whole covers all types of astronomical image processing, including processing of eclipses and solar phenomena, extracting detail from deep-sky, planetary, and widefield images, and offers solutions to some of the most challenging and vexing problems in astronomical image processing. Recognized chapter authors include deep sky experts su...

Paths to dark energy theory and observation

CERN Document Server

Valtonen, Mauri; Chernin, Arthur D; Byrd, Gene

2012-01-01

This work provides the current theory and observations behind the cosmological phenomenon of dark energy. The approach is comprehensivewith rigorous mathematical theory and relevant astronomical observations discussed in context.The book treats the background and history starting with the new-found importance of Einstein's cosmological constant (proposed long ago for the opposite purpose) in dark energy formulation, as well as the frontiers of dark energy.

Comparison of Classical Test Theory and Item Response Theory in Individual Change Assessment

NARCIS (Netherlands)

Jabrayilov, Ruslan; Emons, Wilco H. M.; Sijtsma, Klaas

2016-01-01

Clinical psychologists are advised to assess clinical and statistical significance when assessing change in individual patients. Individual change assessment can be conducted using either the methodologies of classical test theory (CTT) or item response theory (IRT). Researchers have been optimistic

Theory Testing Using Case Studies

DEFF Research Database (Denmark)

Sørensen, Pernille Dissing; Løkke, Ann-Kristina

2006-01-01

design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive...

Astronomía Mocoví

Science.gov (United States)

López, A.; Giménez Benitez, S.; Fernández, L.

El presente trabajo, es una revisión crítica de la astronomía en la cultura Mocoví, aportando a lo realizado previamente por Lehmann Nistche (Lehmann Nistche, 1924 y 1927) el resultado de nuestro trabajo de campo. Un mayor conocimiento de las cosmovisiones de las etnias de esta área es fundamental para una mejor comprensión de la dispersión de las ideas cosmológicas entre los pueblos aborígenes americanos, dada la importancia del corredor chaqueño como conexión entre las altas culturas andinas, la mesopotamia y la región pampeana (Susnik, 1972). Para ello se realiza una comparación con otras cosmovisiones del área americana. Nuestro aporte se enmarca dentro de las actuales líneas de trabajo mundialmente en desarrollo en Astronomía en la Cultura.

A test theory of special relativity

International Nuclear Information System (INIS)

Mansouri, R.; Sexl, R.U.

1977-01-01

Various second-order optical tests of special relativity are discussed within the framework of a test theory developed previously. Owing to the low accuracy of the Kennedy-Thorndike experiment, the Lorentz contraction is known by direct experiments only to an accuracy of a few percent. To improve this accuracy several experiments are suggested. (author)

Top astronomers head to the city. Experts to talk on exciting quasar discoveries.

CERN Multimedia

Grant, S

2002-01-01

The UK National Astronomy Meeting - NAM 2002 - is at Bristol University this week. The meeting is one of the most important regular gatherings of astronomers in the UK. Sponsored by the Royal Astronomical Society and PPARC, it should attract about 300 astronomers from the UK and beyond.

Nicolas-Louis De La Caille astronomer and geodesist

CERN Document Server

Glass, I S

2013-01-01

La Caille was one of the observational astronomers and geodesists who followed Newton in developing ideas about celestial mechanics and the shape of the earth. He provided data to the great 18th-century mathematicians involved in understanding the complex gravitational effects that the heavenly bodies have on one another. Observing from the Cape of Good Hope, he made the first ever telescopic sky survey and gave many of the southern constellations their present-day names. He measured the paths of the planets and determined their distances by trigonometry. In addition, he made a controversial measurement of the radius of the earth that seemed to prove it was pear-shaped. On a practical level, La Caille developed the method of `Lunars' for determining longitudes at sea. He mapped the Cape. As an influential teacher he propagated Newton's theory of universal gravitation at a time when it was only beginning to be accepted on the European continent. This book gives the most comprehensive overview so far avail...

Nursing intellectual capital theory: testing selected propositions.

Science.gov (United States)

Covell, Christine L; Sidani, Souraya

2013-11-01

To test the selected propositions of the middle-range theory of nursing intellectual capital. The nursing intellectual capital theory conceptualizes nursing knowledge's influence on patient and organizational outcomes. The theory proposes nursing human capital, nurses' knowledge, skills and experience, is related to the quality of patient care and nurse recruitment and retention of an inpatient care unit. Two factors in the work environment, nurse staffing and employer support for nurse continuing professional development, are proposed to influence nursing human capital's association with patient and organizational outcomes. A cross-sectional survey design. The study took place in 2008 in six Canadian acute care hospitals. Financial, human resource and risk data were collected from hospital departments and unit managers. Clearly specified empirical indicators quantified the study variables. The propositions of the theory were tested with data from 91 inpatient care units using structural equation modelling. The propositions associated with the nursing human capital concept were supported. The propositions associated with the employer support for nurse continuing professional development concept were not. The proposition that nurse staffing's influences on patient outcomes was mediated by the nursing human capital of an inpatient unit, was partially supported. Some of the theory's propositions were empirically validated. Additional theoretical work is needed to refine the operationalization and measurement of some of the theory's concepts. Further research with larger samples of data from different geographical settings and types of hospitals is required to determine if the theory can withstand empirical scrutiny. © 2013 Blackwell Publishing Ltd.

AWOB: A Collaborative Workbench for Astronomers

Science.gov (United States)

Kim, J. W.; Lemson, G.; Bulatovic, N.; Makarenko, V.; Vogler, A.; Voges, W.; Yao, Y.; Kiefl, R.; Koychev, S.

2015-09-01

We present the Astronomers Workbench (AWOB1), a web-based collaboration and publication platform for a scientific project of any size, developed in collaboration between the Max-Planck institutes of Astrophysics (MPA) and Extra-terrestrial Physics (MPE) and the Max-Planck Digital Library (MPDL). AWOB facilitates the collaboration between geographically distributed astronomers working on a common project throughout its whole scientific life cycle. AWOB does so by making it very easy for scientists to set up and manage a collaborative workspace for individual projects, where data can be uploaded and shared. It supports inviting project collaborators, provides wikis, automated mailing lists, calendars and event notification and has a built in chat facility. It allows the definition and tracking of tasks within projects and supports easy creation of e-publications for the dissemination of data and images and other resources that cannot be added to submitted papers. AWOB extends the project concept to larger scale consortia, within which it is possible to manage working groups and sub-projects. The existing AWOB instance has so far been limited to Max-Planck members and their collaborators, but will be opened to the whole astronomical community. AWOB is an open-source project and its source code is available upon request. We intend to extend AWOB's functionality also to other disciplines, and would greatly appreciate contributions from the community.

Skype Me! Astronomers, Students, and Cutting-Edge Research

Science.gov (United States)

Hickox, Ryan C.; Gauthier, Adrienne J.

2014-06-01

A primary goal of many university science courses is to promote understanding of the process of contemporary scientific inquiry. One powerful way to achieve this is for students to explore current research and then interact directly with the leading scientist, the feasibility of which has recently increased dramatically due to free online video communication tools. We report on a program implemented at Dartmouth College in which students connect with a guest astronomer through Skype (video chat). The Skype session is wrapped in a larger activity where students explore current research articles, interact with the astronomer, and then reflect on the experience. The in-class Skype discussions require a small time commitment from scientists (20-30 minutes, with little or no need for preparation) while providing students direct access to researchers at the cutting edge of modern astronomy. We outline the procedures used to implement these discussions, and present qualitative assessments of student's understanding of the process of research, as well as feedback from the guest astronomers.

Breakthrough! 100 astronomical images that changed the world

CERN Document Server

Gendler, Robert

2015-01-01

This unique volume by two renowned astrophotographers unveils the science and history behind 100 of the most significant astronomical images of all time. The authors have carefully selected their list of images from across time and technology to bring to the reader the most relevant photographic images spanning all eras of modern astronomical history.    Based on scientific evidence today we have a basic notion of how Earth and the universe came to be. The road to this knowledge was paved with 175 years of astronomical images acquired by the coupling of two revolutionary technologies – the camera and telescope. With ingenuity and determination humankind would quickly embrace these technologies to tell the story of the cosmos and unravel its mysteries.   This book presents in pictures and words a photographic chronology of our aspiration to understand the universe. From the first fledgling attempts to photograph the Moon, planets, and stars to the marvels of orbiting observatories that record the cosmos a...

The PACA Project: When Amateur Astronomers Become Citizen Scientists

Science.gov (United States)

Yanamandra-Fisher, P. A.

2014-12-01

The Pro-Am Collaborative Astronomy (PACA) project evolved from the observational campaign of C/2012 S1 or C/ISON in 2013. Following the success of the professional-amateur astronomer collaboration in scientific research via social media, it is now implemented in other comet observing campaigns. While PACA identifies a consistent collaborative approach to pro-am collaborations, given the volume of data generated for each campaign, new ways of rapid data analysis, mining access and storage are needed. Several interesting results emerged from the synergistic inclusion of both social media and amateur astronomers: (1) the establishment of a network of astronomers and related professionals, that can be galvanized into action on short notice to support observing campaigns; (2) assist in various science investigations pertinent to the campaign; (3) provide an alert-sounding mechanism should the need arise; (4) immediate outreach and dissemination of results via our media/blogger members; (5) provide a forum for discussions between the imagers and modelers to help strategize the observing campaign for maximum benefit. In 2014, two new comet observing campaigns involving pro-am collaborations have been initiated: (1) C/2013 A1 (C/SidingSpring) and (2) 67P/Churyumov-Gerasimenko (CG), target for ESA/Rosetta mission. The evolving need for individual customized observing campaigns has been incorporated into the evolution of PACA portal that currently is focused on comets: from supporting observing campaigns of current comets, legacy data, historical comets; interconnected with social media and a set of shareable documents addressing observational strategies; consistent standards for data; data access, use, and storage, to align with the needs of professional observers. The integration of science, observations by professional and amateur astronomers, and various social media provides a dynamic and evolving collaborative partnership between professional and amateur astronomers

A website for astronomical news in Spanish

Science.gov (United States)

Ortiz-Gil, A.

2008-06-01

Noticias del Cosmos is a collection of web pages within the Astronomical Observatory of the University of Valencia's website where we publish short daily summaries of astronomical press releases. Most, if not all of, the releases are originally written in English, and often Spanish readers may find them difficult to understand because not many people are familiar with the scientific language employed in these releases. Noticias del Cosmos has two principal aims. First, we want to communicate the latest astronomical news on a daily basis to a wide Spanish-speaking public who would otherwise not be able to read them because of the language barrier. Second, daily news can be used as a tool to introduce the astronomical topics of the school curriculum in a more immediate and relevant way. Most of the students at school have not yet reached a good enough level in their knowledge of English to fully understand a press release, and Noticias del Cosmos offers them and their teachers this news in their mother tongue. During the regular programme of school visits at the Observatory we use the news as a means of showing that there is still a lot to be discovered. So far the visits to the website have been growing steadily. Between June 2003 and June 2007 we had more than 30,000 visits (excluding 2006). More than 50% of the visits come from Spain, followed by visitors from South and Central America. The feedback we have received from teachers so far has been very positive, showing the usefulness of news items in the classroom when teaching astronomy.

In the Jungle of Astronomical On--line Data Services

Science.gov (United States)

Egret, D.

The author tried to survive in the jungle of astronomical on--line data services. In order to find efficient answers to common scientific data retrieval requests, he had to collect many pieces of information, in order to formulate typical user scenarios, and try them against a number of different data bases, catalogue services, or information systems. He discovered soon how frustrating treasure coffers may be when their keys are not available, but he realized also that nice widgets and gadgets are of no help when the information is not there. And, before long, he knew he would have to navigate through several systems because no one was yet offering a general answer to all his questions. I will present examples of common user scenarios and show how they were tested against a number of services. I will propose some elements of classification which should help the end-user to evaluate how adequate the different services may be for providing satisfying answers to specific queries. For that, many aspects of the user interaction will be considered: documentation, access, query formulation, functionalities, qualification of the data, overall efficiency, etc. I will also suggest possible improvements to the present situation: the first of them being to encourage system managers to increase collaboration between one another, for the benefit of the whole astronomical community. The subjective review I will present, is based on publicly available astronomical on--line services from the U.S. and from Europe, most of which (excepting the newcomers) were described in ``Databases and On-Line Data in Astronomy", (Albrecht & Egret, eds, 1991): this includes databases (such as NED and Simbad ), catalog services ( StarCat , DIRA , XCatScan , etc.), and information systems ( ADS and ESIS ).

The Associate Principal Astronomer for AI Management of Automatic Telescopes

Science.gov (United States)

Henry, Gregory W.

1998-01-01

This research program in scheduling and management of automatic telescopes had the following objectives: 1. To field test the 1993 Automatic Telescope Instruction Set (ATIS93) programming language, which was specifically developed to allow real-time control of an automatic telescope via an artificial intelligence scheduler running on a remote computer. 2. To develop and test the procedures for two-way communication between a telescope controller and remote scheduler via the Internet. 3. To test various concepts in Al scheduling being developed at NASA Ames Research Center on an automatic telescope operated by Tennessee State University at the Fairborn Observatory site in southern Arizona. and 4. To develop a prototype software package, dubbed the Associate Principal Astronomer, for the efficient scheduling and management of automatic telescopes.

South African Astronomical Observatory

International Nuclear Information System (INIS)

1987-01-01

Work at the South African Astronomical Observatory (SAAO) in recent years, by both staff and visitors, has made major contributions to the fields of astrophysics and astronomy. During 1986 the SAAO has been involved in studies of the following: galaxies; celestial x-ray sources; magellanic clouds; pulsating variables; galactic structure; binary star phenomena; nebulae and interstellar matter; stellar astrophysics; open clusters; globular clusters, and solar systems

On astronomical drawing [1846

Science.gov (United States)

Smyth, Charles Piazzi

Reprinted from the Memoirs of the Royal Astronomical Society 15, 1846, pp. 71-82. With annotations and illustrations added by Klaus Hentschel. The activities of the Astronomer Royal for Scotland, Charles Piazzi Smyth (1819-1900), include the triangulation of South African districts, landscape painting, day-to-day or tourist sketching, the engraving and lithographing of prominent architectural sites, the documentary photography of the Egyptian pyramids or the Tenerife Dragon tree, and `instant photographs' of the clouds above his retirement home in Clova, Ripon. His colorful records of the aurora polaris, and solar and terrestrial spectra all profited from his trained eye and his subtle mastery of the pen and the brush. As his paper on astronomical drawing, which we chose to reproduce in this volume, amply demonstrates, he was conversant in most of the print technology repertoire that the 19th century had to offer, and carefully selected the one most appropriate to each sujet. For instance, he chose mezzotint for the plates illustrating Maclear's observations of Halley's comet in 1835/36, so as to achieve a ``rich profundity of shadows, the deep obscurity of which is admirably adapted to reproduce those fine effects of chiaroscuro frequently found in works where the quantity of dark greatly predominates.'' The same expertise with which he tried to emulate Rembrandt's chiaroscuro effects he applied to assessing William and John Herschel's illustrations of nebulae, which appeared in print between 1811 and 1834. William Herschel's positive engraving, made partly by stippling and partly by a coarse mezzotint, receives sharp admonishment because of the visible ruled crossed lines in the background and the fact that ``the objects, which are also generally too light, [have] a much better definition than they really possess.'' On the other hand, John Herschel's illustration of nebulae and star clusters, given in negative, ``in which the lights are the darkest part of the

Testing rank-dependent utility theory for health outcomes.

Science.gov (United States)

Oliver, Adam

2003-10-01

Systematic violations of expected utility theory (EU) have been reported in the context of both money and health outcomes. Rank-dependent utility theory (RDU) is currently the most popular and influential alternative theory of choice under circumstances of risk. This paper reports a test of the descriptive performance of RDU compared to EU in the context of health. When one of the options is certain, violations of EU that can be explained by RDU are found. When both options are risky, no evidence that RDU is a descriptive improvement over EU is found, though this finding may be due to the low power of the tests. Copyright 2002 John Wiley & Sons, Ltd.

Global Vlasov simulation on magnetospheres of astronomical objects

International Nuclear Information System (INIS)

Umeda, Takayuki; Ito, Yosuke; Fukazawa, Keiichiro

2013-01-01

Space plasma is a collisionless, multi-scale, and highly nonlinear medium. There are various types of self-consistent computer simulations that treat space plasma according to various approximations. We develop numerical schemes for solving the Vlasov (collisionless Boltzmann) equation, which is the first-principle kinetic equation for collisionless plasma. The weak-scaling benchmark test shows that our parallel Vlasov code achieves a high performance and a high scalability. Currently, we use more than 1000 cores for parallel computations and apply the present parallel Vlasov code to various cross-scale processes in space plasma, such as a global simulation on the interaction between solar/stellar wind and magnetospheres of astronomical objects

Astronomers find distant planet like Jupiter

CERN Multimedia

2003-01-01

Astronomers searching for planetary systems like our solar system have found a planet similar to Jupiter orbiting a nearby star similar to our Sun, about 90 light-years from Earth, according to researchers (1/2 page).

The Top Ten Astronomical 'breakthroughs' of the 20th century

Directory of Open Access Journals (Sweden)

Hughes, D. W.

2007-10-01

Full Text Available Astronomy was revolutionized in the 20th century. The electron was discovered in 1897 and this transformed spectroscopy and introduced plasma and magnetohydrodynamic physics and astro-chemistry. Einstein’s E = mc2, solved the problem of stellar energy generation and spawned the study of elemental nuclear synthesis. Large telescopes led to a boom in astronomical spectroscopic and photometric data collection, leading to such cornerstones as the Hertzprung-Russell diagram and the mass-luminosity relationship, and to the realization that the Universe contained a multitude of galaxies and was expanding. Radio astronomy was introduced and the advent of the space age saw the astronomical wavelength range expand into the ultraviolet, X-ray and gamma-ray regions, as well as the infrared and millimetre. We also startedwandering around roaming the Solar System instead of merely glimpsing its members from the bottom of our warm, turbulent atmosphere. Astronomical “breakthroughs” abounded. We have asked astronomers to select their “top ten” and these are listed and discussed in this paper.

Dante, astrología y astronomía

OpenAIRE

Gangui, Alejandro

2017-01-01

En este artículo, los versos de Dante Alighieri nos llevan a reflexionar acerca de los diferentes métodos -cada vez más divergentes- con los que la ciencia y las creencias se aproximan a la realidad. Fil: Gangui, Alejandro. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Físi...

Early Tests of Piagetian Theory Through World War II.

Science.gov (United States)

Beins, Bernard C

2016-01-01

Psychologists recognized the importance of Jean Piaget's theory from its inception. Within a year of the appearance of his first book translated into English, The Language and Thought of the Child (J. Piaget, 1926) , it had been reviewed and welcomed; shortly thereafter, psychologists began testing the tenets of the theory empirically. The author traces the empirical testing of his theory in the 2 decades following publication of his initial book. A review of the published literature through the World War II era reveals that the research resulted in consistent failure to support the theoretical mechanisms that Piaget proposed. Nonetheless, the theory ultimately gained traction to become the bedrock of developmental psychology. Reasons for its persistence may include a possible lack of awareness by psychologists about the lack of empirical support, its breadth and complexity, and a lack of a viable alternate theory. As a result, the theory still exerts influence in psychology even though its dominance has diminished.

TMT in the Astronomical Landscape of the 2020s

Science.gov (United States)

Dickinson, Mark; Inami, Hanae

2014-07-01

Thirty Meter Telescope Observatory and NOAO will host the second TMT Science Forum at Loews Ventana Canyon Resort in Tucson, Arizona. The TMT Science Forum is an an annual gathering of astronomers, educators, and observatory staff, who meet to explore TMT science, instrumentation, observatory operations, archiving and data processing, astronomy education, and science, technology, engineering, and math (STEM) issues. It is an opportunity for astronomers from the international TMT partners and from the US-at-large community to learn about the observatory status, discuss and plan cutting-edge science, establish collaborations, and to help shape the future of TMT. One important theme for this year's Forum will be the synergy between TMT and other facilities in the post-2020 astronomical landscape. There will be plenary sessions, an instrumentation workshop, topical science sessions and meetings of the TMT International Science Development Teams (ISDTs).

Astronomy Legacy Project - Pisgah Astronomical Research Institute

Science.gov (United States)

Barker, Thurburn; Castelaz, Michael W.; Rottler, Lee; Cline, J. Donald

2016-01-01

Pisgah Astronomical Research Institute (PARI) is a not-for-profit public foundation in North Carolina dedicated to providing hands-on educational and research opportunities for a broad cross-section of users in science, technology, engineering and math (STEM) disciplines. In November 2007 a Workshop on a National Plan for Preserving Astronomical Photographic Data (2009ASPC,410,33O, Osborn, W. & Robbins, L) was held at PARI. The result was the establishment of the Astronomical Photographic Data Archive (APDA) at PARI. In late 2013 PARI began ALP (Astronomy Legacy Project). ALP's purpose is to digitize an extensive set of twentieth century photographic astronomical data housed in APDA. Because of the wide range of types of plates, plate dimensions and emulsions found among the 40+ collections, plate digitization will require a versatile set of scanners and digitizing instruments. Internet crowdfunding was used to assist in the purchase of additional digitization equipment that were described at AstroPlate2014 Plate Preservation Workshop (www.astroplate.cz) held in Prague, CZ, March, 2014. Equipment purchased included an Epson Expression 11000XL scanner and two Nikon D800E cameras. These digital instruments will compliment a STScI GAMMA scanner now located in APDA. GAMMA will be adapted to use an electroluminescence light source and a digital camera with a telecentric lens to achieve high-speed high-resolution scanning. The 1μm precision XY stage of GAMMA will allow very precise positioning of the plate stage. Multiple overlapping CCD images of small sections of each plate, tiles, will be combined using a photo-mosaic process similar to one used in Harvard's DASCH project. Implementation of a software pipeline for the creation of a SQL database containing plate images and metadata will be based upon APPLAUSE as described by Tuvikene at AstroPlate2014 (www.astroplate.cz/programs/).

Astronomers Win Protection for Key Part of Radio Spectrum

Science.gov (United States)

2000-06-01

Astronomers using the millimeter-wave region of the radio spectrum have won crucial protection for their science. Dedicated allocations for radio astronomy have been given final approval by the 2,500 delegates to the World Radiocommunication Conference (WRC-00), which recently concluded a month of deliberations in Istanbul, Turkey. Radio services can transmit in these parts of the spectrum as long as they don't hinder astronomers' attempts to catch faint signals from the cosmos. The new allocations represent the culmination of more than three years of cooperative planning by radio astronomers in many countries. Millimeter waves -- high-frequency radio waves -- have come of age as an astronomical tool in the last ten years. They are one of the last technological frontiers for astronomers. WRC-00 has protected for science all the frequencies between 71 and 275 Gigahertz (GHz) that radio astronomers currently use, adding more than 90 GHz of spectrum to the 44 GHz already set aside in this frequency range. As a result, radio astronomy is now allocated most of the frequencies between 71 and 275 GHz that can get through the Earth's atmosphere. "We have formal access to all three atmospheric 'windows', apart from their very edges," said Dr. Tom Gergely of the National Science Foundation, one of the U.S. delegates to WRC-00. The WRC also changed most of the frequencies allocated to satellite downlinks within the 71-275 GHz range to frequencies not used for science. Since no satellites yet operate at these high frequencies, no equipment needs to be altered. "Commercial technologies are just starting to develop above 50 GHz," said Dr. Klaus Ruf, Chairman of the Inter-Union Commission for the Allocation of Frequencies. "The WRC's actions mean that, when they are, radio astronomers should be able to share this part of the spectrum with most terrestrial services." The World Radiocommunication Conference is held every two or three years. Here member countries of the

Maraghe Observatory and an Effort towards Retrieval of Architectural Design of Astronomical Units

Directory of Open Access Journals (Sweden)

Javad Shekari Niri

2015-03-01

Full Text Available Maraghe observatory was built by such engineers as Moayiededdin Orozi etc. under supervision of Khaje Nasireddin Tousi in 7th century AH. The most significant feature associated with Maraghe observatory is the fact that architecture is employed to achieve astronomical purposes in this site. The reason for preferring observatory by astronomers was the fact that these units are superior to wooden and metal instruments with respect to accuracy, no size limitations, etc. Architectural design and function of astronomical units of Maraghe observatory site after discovery of its foundation in the course of explorations before Islamic Revolution remained unclear until recent years. After conducting required studies and investigations, the author managed to find significant cues and after some precise comparisons, he succeeded to recover the main design and function of some astronomical units of this international center. Based on these findings these astronomical structures can reliably be rebuilt. This research showed that every circular or polygonal building cannot be considered as an observatory. For example form and function of cemetery structures are completely different with astronomical ones. Following this research also valuable results were obtained in relation to stone architectural structures present on Maraghe observatory hill. In addition, claims about invention of astronomical units of Maraghe observatory by non-Iranian scientists are rejected and rights of Iranian scientists are rationally defended in this regard.

GalileoMobile: Astronomical activities in schools

Science.gov (United States)

Dasi Espuig, Maria; Vasquez, Mayte; Kobel, Philippe

GalileoMobile is an itinerant science education initiative run on a voluntary basis by an international team of astronomers, educators, and science communicators. Our team's main goal is to make astronomy accessible to schools and communities around the globe that have little or no access to outreach actions. We do this by performing teacher workshops, activities with students, and donating educational material. Since the creation of GalileoMobile in 2008, we have travelled to Chile, Bolivia, Peru, India, and Uganda, and worked with 56 schools in total. Our activities are centred on the GalileoMobile Handbook of Activities that comprises around 20 astronomical activities which we adapted from many different sources, and translated into 4 languages. The experience we gained in Chile, Bolivia, Peru, India, and Uganda taught us that (1) bringing experts from other countries was very stimulating for children as they are naturally curious about other cultures and encourages a collaboration beyond borders; (2) high-school students who were already interested in science were always very eager to interact with real astronomers doing research to ask for career advice; (3) inquiry-based methods are important to make the learning process more effective and we have therefore, re-adapted the activities in our Handbook according to these; (4) local teachers and university students involved in our activities have the potential to carry out follow-up activities, and examples are those from Uganda and India.

Astronomical Spectroscopy A Short History

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 5. Astronomical Spectroscopy A Short History. J C Bhattacharyya. General Article Volume 3 Issue 5 May 1998 pp 24-29. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/003/05/0024-0029 ...

QTest: Quantitative Testing of Theories of Binary Choice.

Science.gov (United States)

Regenwetter, Michel; Davis-Stober, Clintin P; Lim, Shiau Hong; Guo, Ying; Popova, Anna; Zwilling, Chris; Cha, Yun-Shil; Messner, William

2014-01-01

The goal of this paper is to make modeling and quantitative testing accessible to behavioral decision researchers interested in substantive questions. We provide a novel, rigorous, yet very general, quantitative diagnostic framework for testing theories of binary choice. This permits the nontechnical scholar to proceed far beyond traditionally rather superficial methods of analysis, and it permits the quantitatively savvy scholar to triage theoretical proposals before investing effort into complex and specialized quantitative analyses. Our theoretical framework links static algebraic decision theory with observed variability in behavioral binary choice data. The paper is supplemented with a custom-designed public-domain statistical analysis package, the QTest software. We illustrate our approach with a quantitative analysis using published laboratory data, including tests of novel versions of "Random Cumulative Prospect Theory." A major asset of the approach is the potential to distinguish decision makers who have a fixed preference and commit errors in observed choices from decision makers who waver in their preferences.

QTest: Quantitative Testing of Theories of Binary Choice

Science.gov (United States)

Regenwetter, Michel; Davis-Stober, Clintin P.; Lim, Shiau Hong; Guo, Ying; Popova, Anna; Zwilling, Chris; Cha, Yun-Shil; Messner, William

2014-01-01

The goal of this paper is to make modeling and quantitative testing accessible to behavioral decision researchers interested in substantive questions. We provide a novel, rigorous, yet very general, quantitative diagnostic framework for testing theories of binary choice. This permits the nontechnical scholar to proceed far beyond traditionally rather superficial methods of analysis, and it permits the quantitatively savvy scholar to triage theoretical proposals before investing effort into complex and specialized quantitative analyses. Our theoretical framework links static algebraic decision theory with observed variability in behavioral binary choice data. The paper is supplemented with a custom-designed public-domain statistical analysis package, the QTest software. We illustrate our approach with a quantitative analysis using published laboratory data, including tests of novel versions of “Random Cumulative Prospect Theory.” A major asset of the approach is the potential to distinguish decision makers who have a fixed preference and commit errors in observed choices from decision makers who waver in their preferences. PMID:24999495

The data analysis facilities that astronomers want

International Nuclear Information System (INIS)

Disney, M.

1985-01-01

This paper discusses the need and importance of data analysis facilities and what astronomers ideally want. A brief survey is presented of what is available now and some of the main deficiencies and problems with today's systems are discussed. The main sources of astronomical data are presented incuding: optical photographic, optical TV/CCD, VLA, optical spectros, imaging x-ray satellite, and satellite planetary camera. Landmark discoveries are listed in a table, some of which include: our galaxy as an island, distance to stars, H-R diagram (stellar structure), size of our galaxy, and missing mass in clusters. The main problems at present are discussed including lack of coordinated effort and central planning, differences in hardware, and measuring performance

On the Relationship between Classical Test Theory and Item Response Theory: From One to the Other and Back

Science.gov (United States)

Raykov, Tenko; Marcoulides, George A.

2016-01-01

The frequently neglected and often misunderstood relationship between classical test theory and item response theory is discussed for the unidimensional case with binary measures and no guessing. It is pointed out that popular item response models can be directly obtained from classical test theory-based models by accounting for the discrete…

Grigor Narekatsi's astronomical insights

Science.gov (United States)

Poghosyan, Samvel

2015-07-01

What stand out in the solid system of Gr. Narekatsi's naturalistic views are his astronomical insights on the material nature of light, its high speed and the Sun being composed of "material air". Especially surprising and fascinating are his views on stars and their clusters. What astronomers, including great Armenian academician V. Ambartsumian (scattering of stellar associations), would understand and prove with much difficulty thousand years later, Narekatsi predicted in the 10th century: "Stars appear and disappear untimely", "You who gather and scatter the speechless constellations, like a flock of sheep". Gr. Narekatsti's reformative views were manifested in all the spheres of the 10th century social life; he is a reformer of church life, great language constructor, innovator in literature and music, freethinker in philosophy and science. His ideology is the reflection of the 10th century Armenian Renaissance. During the 9th-10th centuries, great masses of Armenians, forced to migrate to the Balkans, took with them and spread reformative ideas. The forefather of the western science, which originated in the period of Reformation, is considered to be the great philosopher Nicholas of Cusa. The study of Gr. Narekatsti's logic and naturalistic views enables us to claim that Gr. Narekatsti is the great grandfather of European science.

Corral framework: Trustworthy and fully functional data intensive parallel astronomical pipelines

Science.gov (United States)

Cabral, J. B.; Sánchez, B.; Beroiz, M.; Domínguez, M.; Lares, M.; Gurovich, S.; Granitto, P.

2017-07-01

Data processing pipelines represent an important slice of the astronomical software library that include chains of processes that transform raw data into valuable information via data reduction and analysis. In this work we present Corral, a Python framework for astronomical pipeline generation. Corral features a Model-View-Controller design pattern on top of an SQL Relational Database capable of handling: custom data models; processing stages; and communication alerts, and also provides automatic quality and structural metrics based on unit testing. The Model-View-Controller provides concept separation between the user logic and the data models, delivering at the same time multi-processing and distributed computing capabilities. Corral represents an improvement over commonly found data processing pipelines in astronomysince the design pattern eases the programmer from dealing with processing flow and parallelization issues, allowing them to focus on the specific algorithms needed for the successive data transformations and at the same time provides a broad measure of quality over the created pipeline. Corral and working examples of pipelines that use it are available to the community at https://github.com/toros-astro.

Amateur astronomers in support of observing campaigns

Science.gov (United States)

Yanamandra-Fisher, P.

2014-07-01

The Pro-Am Collaborative Astronomy (PACA) project evolved from the observational campaign of C/2012 S1 or C/ISON. The success of the paradigm shift in scientific research is now implemented in other comet observing campaigns. While PACA identifies a consistent collaborative approach to pro-am collaborations, given the volume of data generated for each campaign, new ways of rapid data analysis, mining access, and storage are needed. Several interesting results emerged from the synergistic inclusion of both social media and amateur astronomers: - the establishment of a network of astronomers and related professionals that can be galvanized into action on short notice to support observing campaigns; - assist in various science investigations pertinent to the campaign; - provide an alert-sounding mechanism should the need arise; - immediate outreach and dissemination of results via our media/blogger members; - provide a forum for discussions between the imagers and modelers to help strategize the observing campaign for maximum benefit. In 2014, two new comet observing campaigns involving pro-am collaborations have been identified: (1) C/2013 A1 (C/Siding Spring) and (2) 67P/Churyumov-Gerasimenko (CG). The evolving need for individual customized observing campaigns has been incorporated into the evolution of PACA (Pro-Am Collaborative Astronomy) portal that currently is focused on comets: from supporting observing campaigns for current comets, legacy data, historical comets; interconnected with social media and a set of shareable documents addressing observational strategies; consistent standards for data; data access, use, and storage, to align with the needs of professional observers. The integration of science, observations by professional and amateur astronomers, and various social media provides a dynamic and evolving collaborative partnership between professional and amateur astronomers. The recent observation of comet 67P, at a magnitude of 21.2, from Siding

Astronomers no longer in the dark

CERN Multimedia

MacMillan, L

2002-01-01

In a significant breakthrough, British and US astronomers have begun to pin down the most elusive material in the universe. They have made a map of dark matter - the heavy, invisible stuff that gives the galaxies their shape (1 page).

LGBT Workplace Issues for Astronomers

Science.gov (United States)

Kay, Laura E.; Danner, R.; Sellgren, K.; Dixon, V.; GLBTQastro

2011-01-01

Federal Equal Employment Opportunity laws and regulations do not provide protection from discrimination on the basis of sexual orientation or gender identity or gender expression. Sexual minority astronomers (including lesbian, gay, bisexual and transgender people; LGBT) can face additional challenges at school and work. Studies show that LGBT students on many campuses report experiences of harassment. Cities, counties, and states may or may not have statutes to protect against such discrimination. There is wide variation in how states and insurance plans handle legal and medical issues for transgender people. Federal law does not acknowledge same-sex partners, including those legally married in the U.S. or in other countries. Immigration rules in the U.S. (and many other, but not all) countries do not recognize same-sex partners for visas, employment, etc. State `defense of marriage act' laws have been used to remove existing domestic partner benefits at some institutions, or benefits can disappear with a change in governor. LGBT astronomers who change schools, institutions, or countries during their career may experience significant differences in their legal, medical, and marital status.

Testing the Neutral Theory of Biodiversity with Human Microbiome Datasets

OpenAIRE

Li, Lianwei; Ma, Zhanshan (Sam)

2016-01-01

The human microbiome project (HMP) has made it possible to test important ecological theories for arguably the most important ecosystem to human health?the human microbiome. Existing limited number of studies have reported conflicting evidence in the case of the neutral theory; the present study aims to comprehensively test the neutral theory with extensive HMP datasets covering all five major body sites inhabited by the human microbiome. Utilizing 7437 datasets of bacterial community samples...

What Lies Behind NSF Astronomer Demographics? Subjectivities of Women, Minorities and Foreign-born Astronomers within Meshworks of Big Science Astronomy

Science.gov (United States)

Guillen, Reynal; Gu, D.; Holbrook, J.; Murillo, L. F.; Traweek, S.

2011-01-01

Our current research focuses on the trajectory of scientists working with large-scale databases in astronomy, following them as they strategically build their careers, digital infrastructures, and make their epistemological commitments. We look specifically at how gender, ethnicity, nationality intersect in the process of subject formation in astronomy, as well as in the process of enrolling partners for the construction of instruments, design and implementation of large-scale databases. Work once figured as merely technical support, such assembling data catalogs, or as graphic design, generating pleasing images for public support, has been repositioned at the core of the field. Some have argued that such databases enable a new kind of scientific inquiry based on data exploration, such as the "fourth paradigm" or "data-driven" science. Our preliminary findings based on oral history interviews and ethnography provide insights into meshworks of women, African-American, "Hispanic," Asian-American and foreign-born astronomers. Our preliminary data suggest African-American men are more successful in sustaining astronomy careers than Chicano and Asian-American men. A distinctive theme in our data is the glocal character of meshworks available to and created by foreign-born women astronomers working at US facilities. Other data show that the proportion of Asian to Asian American and foreign-born Latina/o to Chicana/o astronomers is approximately equal. Futhermore, Asians and Latinas/os are represented in significantly greater numbers than Asian Americans and Chicanas/os. Among professional astronomers in the US, each ethnic minority group is numbered on the order of tens, not hundreds. Project support is provided by the NSF EAGER program to University of California, Los Angeles under award 0956589.

How to test the special theory of relativity on rotating earth

International Nuclear Information System (INIS)

Abolghasem, H.; Khadjehpoor, M.R.; Mansouri, R.

1988-02-01

In the framework of a one parameter test theory of special relativity, the difference between Transport- and Einstein synchronization on the rotating earth is calculated. For the special theory of relativity this difference vanishes. Therefore, experiments in which these synchronization procedures are compared, test the special theory of relativity. (author). 8 refs

Preserving Astronomy's Photographic Legacy: Current State and the Future of North American Astronomical Plates

Science.gov (United States)

Osborn, W.; Robbins, L.

2009-08-01

This book contains articles on preserving astronomy's valuable heritage of photographic observations, most of which are on glass plates. It is intended to serve as a reference for institutions charged with preserving and managing plate archives and astronomers interested in using archival photographic plates in their research. The first portion of the book focuses on previous activities and recommendations related to plate archiving. These include actions taken by the International Astronomical Union, activities in Europe and a detailed account of a workshop on preserving astronomical photographic data held in 2007 at the Pisgah Astronomical Research Institute, North Carolina. The workshop discussions covered a wide range of issues that must be considered in any effort to archive plates and culminated in a set of recommendations on preserving, cataloging and making publicly available these irreplaceable data. The second part of the book reports on some recent efforts to implement the recommendations. These include essays on the recently established Astronomical Photographic Data Archive, projects to make photographic collections available electronically, evaluations of commercial scanners for digitization of astronomical plates and the case for the continuing value of these data along with a report on the census of astronomical plate collections in North America carried out in 2008. The census cataloged the locations, numbers, and types of astronomical plates in the US and Canada. Comprehensive appendices identify all the significant collections in North America and detail the current contents, state and status of their holdings.

Recent Advances for LGBT Astronomers in the United States

Science.gov (United States)

Dixon, William V.; Rigby, Jane; Oppenheimer, Rebecca

2015-08-01

The legal environment for lesbian, gay, bisexual, and transgender (LGBT) astronomers in the United States has changed dramatically in recent years. In 2013, the Supreme Court ruled that Section 3 of the Defense of Marriage Act (DOMA), which had barred the federal government from recognizing same-sex marriages, was unconstitutional. This decision particularly affects astronomers, since astronomers in the U.S. are more likely than the general population to be foreign nationals, to have a foreign-born spouse, or to work for the federal government. In 2014, the Attorney General directed the Department of Justice to take the position in litigation that the protection of Title VII of the Civil Rights Act of 1964 extends to claims of discrimination based on an individual’s gender identity, including transgender status. Title VII makes it unlawful for employers to discriminate in the employment of an individual “because of such individual’s... sex,” among other protected characteristics. As of March 2015, more than 70% of the population lives in states that recognize same-sex marriage, and the Supreme Court is expected to rule on the constitutionality of the remaining same-sex marriage bans during the current term. In this poster, we discuss these advances and their implications for the personal and professional lives of LGBT astronomers across the United States.

How did the Supreme Court ruling on DOMA affect astronomers?

Science.gov (United States)

Rigby, Jane R.; The AAS Working Group on LGBTIQ Equality

2014-01-01

In June 2013, the United States Supreme Court ruled that Section 3 of the Defense of Marriage Act (DOMA) was unconstitutional. Section 3 had barred the federal government from recognizing same-sex marriages. The decision in United States v. Windsor, made headlines around the world, and particularly affected astronomers, since astronomers in the US are more likely than the general population to be foreign nationals, to have a foreign-born spouse, or to work for the federal government. In this poster, we highlight some of the real-world ways that the Windsor case has affected US astronomers and our profession. Bi-national couples can now apply for green cards granting permanent residency. Scientists who work for the federal government, including NASA and the NSF, can now obtain health insurance for a same-sex spouse. From taxes to death benefits, health insurance to daycare, immigration to ethics laws, the end of S3 of DOMA has had profoundly improved the lives of US scientists who are lesbian, gay, bisexual, or transgender (LGBT). Here we, highlight several real-world examples of how DOMA's demise has improved the lives and careers of US astronomer.

Item response theory analysis of the mechanics baseline test

Science.gov (United States)

Cardamone, Caroline N.; Abbott, Jonathan E.; Rayyan, Saif; Seaton, Daniel T.; Pawl, Andrew; Pritchard, David E.

2012-02-01

Item response theory is useful in both the development and evaluation of assessments and in computing standardized measures of student performance. In item response theory, individual parameters (difficulty, discrimination) for each item or question are fit by item response models. These parameters provide a means for evaluating a test and offer a better measure of student skill than a raw test score, because each skill calculation considers not only the number of questions answered correctly, but the individual properties of all questions answered. Here, we present the results from an analysis of the Mechanics Baseline Test given at MIT during 2005-2010. Using the item parameters, we identify questions on the Mechanics Baseline Test that are not effective in discriminating between MIT students of different abilities. We show that a limited subset of the highest quality questions on the Mechanics Baseline Test returns accurate measures of student skill. We compare student skills as determined by item response theory to the more traditional measurement of the raw score and show that a comparable measure of learning gain can be computed.

An astronomical time scale for the Maastrichtian at the Zumaia and Sopelana sections (Basque country, northern Spain)

DEFF Research Database (Denmark)

Batenburg, Sietske J.; Gale, Andy S.; Sprovieri, Mario

2014-01-01

The rhythmically bedded limestone–marl alternations in the coastal cliffs of Sopelana and Zumaia in the Basque country, northern Spain, permit testing and refining of existing Maastrichtian chronologies (latest Cretaceous). The recently established astronomical time scale for the late Maastrichtian...

ARNICA, the Arcetri near-infrared camera: Astronomical performance assessment.

Science.gov (United States)

Hunt, L. K.; Lisi, F.; Testi, L.; Baffa, C.; Borelli, S.; Maiolino, R.; Moriondo, G.; Stanga, R. M.

1996-01-01

The Arcetri near-infrared camera ARNICA was built as a users' instrument for the Infrared Telescope at Gornergrat (TIRGO), and is based on a 256x256 NICMOS 3 detector. In this paper, we discuss ARNICA's optical and astronomical performance at the TIRGO and at the William Herschel Telescope on La Palma. Optical performance is evaluated in terms of plate scale, distortion, point spread function, and ghosting. Astronomical performance is characterized by camera efficiency, sensitivity, and spatial uniformity of the photometry.

Applying artificial intelligence to astronomical databases - a surveyof applicable technology.

Science.gov (United States)

Rosenthal, D. A.

This paper surveys several emerging technologies which are relevant to astronomical database issues such as interface technology, internal database representation, and intelligent data reduction aids. Among the technologies discussed are natural language understanding, frame and object representations, planning, pattern analysis, machine learning and the nascent study of simulated neural nets. These techniques will become increasingly important for astronomical research, and in particular, for applications with large databases.

EDUCATIONAL ASTRONOMICAL OBSERVATIONS ON REMOTE ACCESS TELESCOPES

Directory of Open Access Journals (Sweden)

Ivan P. Kriachko

2016-01-01

Full Text Available The purpose of this article is to show the way of overcoming one of the major problems of astronomy teaching methods in upper secondary school – organization of educational astronomical observations. Nowadays it became possible to perform such observations on remote access telescopes. By using up-to-date informational and communicational technologies, having an opportunity to work with robotic telescopes allows us to organize a unique cognitive and research oriented activities for students while conducting their specialized astronomical studies. Below here is given a brief description of the most significant robotic telescopes and the way of the usage of open remote access telescopic network which was created by professors and scientists of Harvard-Smithsonian Center for Astrophysics, USA.

How do astronomers share data? Reliability and persistence of datasets linked in AAS publications and a qualitative study of data practices among US astronomers.

Science.gov (United States)

Pepe, Alberto; Goodman, Alyssa; Muench, August; Crosas, Merce; Erdmann, Christopher

2014-01-01

We analyze data sharing practices of astronomers over the past fifteen years. An analysis of URL links embedded in papers published by the American Astronomical Society reveals that the total number of links included in the literature rose dramatically from 1997 until 2005, when it leveled off at around 1500 per year. The analysis also shows that the availability of linked material decays with time: in 2011, 44% of links published a decade earlier, in 2001, were broken. A rough analysis of link types reveals that links to data hosted on astronomers' personal websites become unreachable much faster than links to datasets on curated institutional sites. To gauge astronomers' current data sharing practices and preferences further, we performed in-depth interviews with 12 scientists and online surveys with 173 scientists, all at a large astrophysical research institute in the United States: the Harvard-Smithsonian Center for Astrophysics, in Cambridge, MA. Both the in-depth interviews and the online survey indicate that, in principle, there is no philosophical objection to data-sharing among astronomers at this institution. Key reasons that more data are not presently shared more efficiently in astronomy include: the difficulty of sharing large data sets; over reliance on non-robust, non-reproducible mechanisms for sharing data (e.g. emailing it); unfamiliarity with options that make data-sharing easier (faster) and/or more robust; and, lastly, a sense that other researchers would not want the data to be shared. We conclude with a short discussion of a new effort to implement an easy-to-use, robust, system for data sharing in astronomy, at theastrodata.org, and we analyze the uptake of that system to-date.

How Do Astronomers Share Data? Reliability and Persistence of Datasets Linked in AAS Publications and a Qualitative Study of Data Practices among US Astronomers

Science.gov (United States)

Pepe, Alberto; Goodman, Alyssa; Muench, August; Crosas, Merce; Erdmann, Christopher

2014-08-01

We analyze data sharing practices of astronomers over the past fifteen years. An analysis of URL links embedded in papers published by the American Astronomical Society reveals that the total number of links included in the literature rose dramatically from 1997 until 2005, when it leveled off at around 1500 per year. The analysis also shows that the availability of linked material decays with time: in 2011, 44% of links published a decade earlier, in 2001, were broken. A rough analysis of link types reveals that links to data hosted on astronomers' personal websites become unreachable much faster than links to datasets on curated institutional sites. To gauge astronomers' current data sharing practices and preferences further, we performed in-depth interviews with 12 scientists and online surveys with 173 scientists, all at a large astrophysical research institute in the United States: the Harvard-Smithsonian Center for Astrophysics, in Cambridge, MA. Both the in-depth interviews and the online survey indicate that, in principle, there is no philosophical objection to data-sharing among astronomers at this institution. Key reasons that more data are not presently shared more efficiently in astronomy include: the difficulty of sharing large data sets; over reliance on non-robust, non-reproducible mechanisms for sharing data (e.g. emailing it); unfamiliarity with options that make data-sharing easier (faster) and/or more robust; and, lastly, a sense that other researchers would not want the data to be shared. We conclude with a short discussion of a new effort to implement an easy-to-use, robust, system for data sharing in astronomy, at theastrodata.org, and we analyze the uptake of that system to-date.

How do astronomers share data? Reliability and persistence of datasets linked in AAS publications and a qualitative study of data practices among US astronomers.

Directory of Open Access Journals (Sweden)

Alberto Pepe

Full Text Available We analyze data sharing practices of astronomers over the past fifteen years. An analysis of URL links embedded in papers published by the American Astronomical Society reveals that the total number of links included in the literature rose dramatically from 1997 until 2005, when it leveled off at around 1500 per year. The analysis also shows that the availability of linked material decays with time: in 2011, 44% of links published a decade earlier, in 2001, were broken. A rough analysis of link types reveals that links to data hosted on astronomers' personal websites become unreachable much faster than links to datasets on curated institutional sites. To gauge astronomers' current data sharing practices and preferences further, we performed in-depth interviews with 12 scientists and online surveys with 173 scientists, all at a large astrophysical research institute in the United States: the Harvard-Smithsonian Center for Astrophysics, in Cambridge, MA. Both the in-depth interviews and the online survey indicate that, in principle, there is no philosophical objection to data-sharing among astronomers at this institution. Key reasons that more data are not presently shared more efficiently in astronomy include: the difficulty of sharing large data sets; over reliance on non-robust, non-reproducible mechanisms for sharing data (e.g. emailing it; unfamiliarity with options that make data-sharing easier (faster and/or more robust; and, lastly, a sense that other researchers would not want the data to be shared. We conclude with a short discussion of a new effort to implement an easy-to-use, robust, system for data sharing in astronomy, at theastrodata.org, and we analyze the uptake of that system to-date.

Spectral atlas for amateur astronomers a guide to the spectra of astronomical objects and terrestrial light sources

CERN Document Server

Walker, Richard

2017-01-01

Featuring detailed commented spectral profiles of more than one hundred astronomical objects, in colour, this spectral guide documents most of the important and spectroscopically observable objects accessible using typical amateur equipment. It allows you to read and interpret the recorded spectra of the main stellar classes, as well as most of the steps from protostars through to the final stages of stellar evolution as planetary nebulae, white dwarfs or the different types of supernovae. It also presents integrated spectra of stellar clusters, galaxies and quasars, and the reference spectra of some terrestrial light sources, for calibration purposes. Whether used as the principal reference for comparing with your recorded spectra or for inspiring independent observing projects, this atlas provides a breathtaking view into our Universe's past. The atlas is accompanied and supplemented by Spectroscopy for Amateur Astronomers, which explains in detail the methods for recording, processing, analysing and interp...

Generalization of the test theory of relativity to noninertial frames

International Nuclear Information System (INIS)

Abolghasem, G.H.; Khajehpour, M.R.H.; Mansouri, R.

1988-08-01

We present a generalized test theory of special relativity, using a noninertial frame. Within the framework of the special theory of relativity the transport- and Einstein-synchronizations are equivalent on a rigidly rotating disk. But in any theory with a preferred frame such an equivalence does not hold. The time difference resulting from the two synchronization procedures is a measurable quantity within the reach of existing clock systems on the earth. The final result contains a term which depends on the angular velocity of the rotating system, and hence measures an absolute effect. This term is of crucial importance in our test theory of the special relativity. (author). 13 refs

A new astronomical dating of Odysseus return to Ithaca.

Science.gov (United States)

Papamarinopoulos, St. P.; Preka-Papadema, P.; Antonopoulos, P.; Mitropetrou, H.; Tsironi, A.; Mitropetros, P.

The annular solar eclipse, of 30 October 1207 B.C. (Julian Day-JD 1280869), calculated by NASA together with the analysis of the weather's and the environment's description (long nights, plants, animals and peoples' habits) and the astronomical data (guiding constellations and Venus in the east horizon) mentioned by Homer in the epic, constitute an autumn return of Odysseus to Ithaca five days before the above characterized day. The latter offers a precise astronomical dating of the event and dates the legendary Trojan War's end as well.

AAS Publishing News: Astronomical Software Citation Workshop

Science.gov (United States)

Kohler, Susanna

2015-07-01

Do you write code for your research? Use astronomical software? Do you wish there were a better way of citing, sharing, archiving, or discovering software for astronomy research? You're not alone! In April 2015, AAS's publishing team joined other leaders in the astronomical software community in a meeting funded by the Sloan Foundation, with the purpose of discussing these issues and potential solutions. In attendance were representatives from academic astronomy, publishing, libraries, for-profit software sharing platforms, telescope facilities, and grantmaking institutions. The goal of the group was to establish “protocols, policies, and platforms for astronomical software citation, sharing, and archiving,” in the hopes of encouraging a set of normalized standards across the field. The AAS is now collaborating with leaders at GitHub to write grant proposals for a project to develop strategies for software discoverability and citation, in astronomy and beyond. If this topic interests you, you can find more details in this document released by the group after the meeting: http://astronomy-software-index.github.io/2015-workshop/ The group hopes to move this project forward with input and support from the broader community. Please share the above document, discuss it on social media using the hashtag #astroware (so that your conversations can be found!), or send private comments to julie.steffen@aas.org.

Test theories of special relativity: a general critique

International Nuclear Information System (INIS)

Maciel, A.K.A.; Tiomno, J.

1988-01-01

Absolute Spacetime Theories conceived for the purpose of testing Special Relativity (SR) are reviewed. It is found that most theories proposed were in fact SR in different coordinate systems, since in general no specific SR violations were introduced. Models based on possible SR violating mechanisms are considered. Misconceptions in recently published papers are examined. (author) [pt

The Prediction of Item Parameters Based on Classical Test Theory and Latent Trait Theory

Science.gov (United States)

Anil, Duygu

2008-01-01

In this study, the prediction power of the item characteristics based on the experts' predictions on conditions try-out practices cannot be applied was examined for item characteristics computed depending on classical test theory and two-parameters logistic model of latent trait theory. The study was carried out on 9914 randomly selected students…

Longwave Imaging for Astronomical Applications, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — We propose to develop a compact portable longwave camera for astronomical applications. In Phase 1, we successfully developed the eye of the camera, i.e. the focal...

Astronomical calibration of the geological timescale: closing the middle Eocene gap

Science.gov (United States)

Westerhold, T.; Röhl, U.; Frederichs, T.; Bohaty, S. M.; Zachos, J. C.

2015-09-01

To explore cause and consequences of past climate change, very accurate age models such as those provided by the astronomical timescale (ATS) are needed. Beyond 40 million years the accuracy of the ATS critically depends on the correctness of orbital models and radioisotopic dating techniques. Discrepancies in the age dating of sedimentary successions and the lack of suitable records spanning the middle Eocene have prevented development of a continuous astronomically calibrated geological timescale for the entire Cenozoic Era. We now solve this problem by constructing an independent astrochronological stratigraphy based on Earth's stable 405 kyr eccentricity cycle between 41 and 48 million years ago (Ma) with new data from deep-sea sedimentary sequences in the South Atlantic Ocean. This new link completes the Paleogene astronomical timescale and confirms the intercalibration of radioisotopic and astronomical dating methods back through the Paleocene-Eocene Thermal Maximum (PETM, 55.930 Ma) and the Cretaceous-Paleogene boundary (66.022 Ma). Coupling of the Paleogene 405 kyr cyclostratigraphic frameworks across the middle Eocene further paves the way for extending the ATS into the Mesozoic.

The Impact of the Qur'anic Conception of Astronomical Phenomena on Islamic Civilization

Science.gov (United States)

Ahmad, I. A.

Discussions of astronomical phenomena in religious texts usually center around either their literal astronomical content or their symbolic significance. We shall instead consider the use of frequent references to astronomical phenomena in the Qur'an as exhortations to a worldview that ushered in the modern era. The Qur'anic conception of astronomical phenomena had a critical impact on Islamic civilization and the civilizations that followed because it introduced and mandated the adoption of certain attitudes. Among these were a greater respect for empirical data than was common in the preceding Greek civilization and an insistence that the Universe is ruled by a single set of laws. Both of these were rooted in the Islamic concept of tawhîd, the unity of God.

International Astronomical Union Sympoisum No.50

CERN Document Server

Westerlund, B

1973-01-01

Dr J. Landi Dessy, Director of the Astronomical Observatory, Cordoba, Argentina, invited the International Astronomical Union to hold a Symposium in Cordoba in connection with the celebration of the Centennial of the Cordoba Observatory; the date of foundation is October 24, 1871. He proposed that the Symposium should deal with Spectral Classification and Multicolour Photometry as seven years had elapsed since the Symposium No. 24 in Saltsj6baden, and much development had occurred in the field. The invitation and the proposal were accepted by the IAU, and the Symposium was held in Villa Carlos Paz, near Cordoba, between October 18 and October 24, 1971. It was attended by about 50 scientists representing Argentina, Canada, Chile, Den­ mark, France, Germany, Italy, Mexico, Sweden, Switzerland, U.K., U.S.A., Vatican City State and Venezuela. The Symposium was divided into four sessions: 1. Classification of slit spectra, 2. Classification of objective-prism spectra, 3. Photometric classification, 4. Catalogues ...

Large Astronomical Surveys, Catalogs and Databases

Directory of Open Access Journals (Sweden)

Mickaelian A. M.

2012-09-01

Full Text Available We review the status of all-sky and large astronomical surveys and their catalogued data over the whole range of electromagnetic spectrum, from gamma-ray to radio, such as ROSAT in X-ray, GALEX in UV, SDSS and several POSS1/2 based catalogs (APM, MAPS, USNO, GSC in optical, 2MASS and WISE in NIR, IRAS and AKARI in MIR/FIR, NVSS and FIRST in radio range and others. Present astronomical archives contain billions of objects, Galactic as well as extragalactic, and the vast amount of data in them permit new studies and discoveries. Cross-correlations result in revealing new objects and new samples. Very often, dozens of thousands of sources hide a few very interesting ones that are needed to be discovered by comparison of various physical characteristics. Most of the modern databases currently provide VO access to the stored information. This permits not only open access but also fast analysis and managing of these data.

Recruitment and Retention of LGBTIQ Astronomers

Science.gov (United States)

Dixon, William Van Dyke

2012-01-01

While lesbian, gay, bisexual, transgender, intersex, or questioning (LGBTIQ) astronomers face many of the same workplace challenges as women and racial/ethnic minorities, from implicit bias to overt discrimination, other challenges are unique to this group. An obvious example is the absence at many institutions of health insurance and other benefits for the same-sex domestic partners of their employees. More subtle is the psychological toll paid by LGBTIQ astronomers who remain "in the closet," self-censoring every statement about their personal lives. Paradoxically, the culture of the physical sciences, in which sexuality, gender identity, and gender expression are considered irrelevant, can discourage their discussion, further isolating LGBTIQ researchers. Addressing these challenges is not just a matter of fairness; it is an essential tool in the recruitment and retention of the brightest researchers and in assuring their productivity. We will discuss these issues and what individuals and departments can to make their institutions more welcoming to their LGBTIQ colleagues.

Instrument Remote Control via the Astronomical Instrument Markup Language

Science.gov (United States)

Sall, Ken; Ames, Troy; Warsaw, Craig; Koons, Lisa; Shafer, Richard

1998-01-01

The Instrument Remote Control (IRC) project ongoing at NASA's Goddard Space Flight Center's (GSFC) Information Systems Center (ISC) supports NASA's mission by defining an adaptive intranet-based framework that provides robust interactive and distributed control and monitoring of remote instruments. An astronomical IRC architecture that combines the platform-independent processing capabilities of Java with the power of Extensible Markup Language (XML) to express hierarchical data in an equally platform-independent, as well as human readable manner, has been developed. This architecture is implemented using a variety of XML support tools and Application Programming Interfaces (API) written in Java. IRC will enable trusted astronomers from around the world to easily access infrared instruments (e.g., telescopes, cameras, and spectrometers) located in remote, inhospitable environments, such as the South Pole, a high Chilean mountaintop, or an airborne observatory aboard a Boeing 747. Using IRC's frameworks, an astronomer or other scientist can easily define the type of onboard instrument, control the instrument remotely, and return monitoring data all through the intranet. The Astronomical Instrument Markup Language (AIML) is the first implementation of the more general Instrument Markup Language (IML). The key aspects of our approach to instrument description and control applies to many domains, from medical instruments to machine assembly lines. The concepts behind AIML apply equally well to the description and control of instruments in general. IRC enables us to apply our techniques to several instruments, preferably from different observatories.

High energy astrophysics in radio-astronomical form

International Nuclear Information System (INIS)

Laan, H. van der

1980-01-01

The application of high energy astrophysics in observational astronomy, and in particular in radioastronomy, is considered. The current situation of extragalactic HEA, as brought to light by radio-astronomical techniques, is sketched. (C.F.)

Astroinformatics, data mining and the future of astronomical research

Energy Technology Data Exchange (ETDEWEB)

Brescia, Massimo, E-mail: longo@na.infn.it [INAF, Astronomical Obs. of Capodimonte, Via Moiariello 16, I-80131 Napoli (Italy); Longo, Giuseppe [Department of Physics, University Federico II, Via Cintia 6, 80126 Napoli (Italy); Department of Astronomy, Caltech, Pasadena (United States)

2013-08-21

Astronomy, as many other scientific disciplines, is facing a true data deluge which is bound to change both the praxis and the methodology of every day research work. The emerging field of astroinformatics, while on the one end appears crucial to face the technological challenges, on the other is opening new exciting perspectives for new astronomical discoveries through the implementation of advanced data mining procedures. The complexity of astronomical data and the variety of scientific problems, however, call for innovative algorithms and methods as well as for an extreme usage of ICT technologies.

Astroinformatics, data mining and the future of astronomical research

International Nuclear Information System (INIS)

Brescia, Massimo; Longo, Giuseppe

2013-01-01

Astronomy, as many other scientific disciplines, is facing a true data deluge which is bound to change both the praxis and the methodology of every day research work. The emerging field of astroinformatics, while on the one end appears crucial to face the technological challenges, on the other is opening new exciting perspectives for new astronomical discoveries through the implementation of advanced data mining procedures. The complexity of astronomical data and the variety of scientific problems, however, call for innovative algorithms and methods as well as for an extreme usage of ICT technologies

Tests of Theories of Crime in Female Prisoners.

Science.gov (United States)

Lindberg, Marc A; Fugett, April; Adkins, Ashtin; Cook, Kelsey

2017-02-01

Several general theories of crime were tested with path models on 293 female prisoners in a U.S. State prison. The theories tested included Social Bond and Control, Thrill/Risk Seeking, and a new attachment-based Developmental Dynamic Systems model. A large battery of different instruments ranging from measures of risk taking, to a crime addiction scale, to Childhood Adverse Events, to attachments and clinical issues were used. The older general theories of crime did not hold up well under the rigor of path modeling. The new dynamic systems model was supported that incorporated adverse childhood events leading to (a) peer crime, (b) crime addiction, and (c) a measure derived from the Attachment and Clinical Issues Questionnaire (ACIQ) that takes individual differences in attachments and clinical issues into account. The results were discussed in terms of new approaches to Research Defined Criteria of Diagnosis (RDoC) and new approaches to intervention.

"Word of Discovery": A Planetary Example from Volume I of the Astronomical Journal

Science.gov (United States)

Hockey, T.

1998-09-01

In 1850, William Lassell (1799-1880) discovered a series of bright white spots, in the south temperate latitudes of Jupiter, unlike any that that been seen before. Lassell's note on these STZ features is a useful example of how astronomical discoveries of the day were communicated among astronomers. Word of Lassell's Spots spread quickly by nineteenth-century standards. This was due, in part, to the recent appearance of journals devoted exclusively to astronomy. The transition from letters as a means of conveying scientific information to journals is reflected in the propagation of Lassell's announcement: a report of Lassell's description of the white spots to the Royal Astronomical Society appeared in the Monthly Notices of the Royal Astronomical Society along with a woodblock print of one of his drawings. This report reappeared shortly thereafter in German translation. It was part of a letter to the editor of the Astronomische Nachrichten, Heinrich Schumacher (1780-1850), from an English correspondent of his, the Reverend Richard Sheepshanks (1974-1855). (Sheepshanks was himself editor of the Monthly Notices of the Royal Astronomical Society.) It then made its way across the Atlantic as a letter from Schumacher to Benjamin Gould (1824-1896), who published it in the first volume of his upstart Astronomical Journal. There it appears in English, again, as Schumacher quoting Sheepshanks quoting Lassell! The observations by Lassell and William Dawes (1799-1868) of this phenomenon also were the first major planetary discovery made using a silvered-glass reflecting telescope. Lassell's Spots have remained in the "astronomical news" of the last 150 years: Most recently, they appeared worldwide in images showing the Comet Shoemaker-Levy 9 impact sites.

An empirical test of reference price theories using a semiparametric approach

DEFF Research Database (Denmark)

Boztug, Yasemin; Hildebrandt, Lutz

  In this paper we estimate and empirically test different behavioral theories of consumer reference price formation. Two major theories are proposed to model the reference price reaction: assimilation contrast theory and prospect theory. We assume that different consumer segments will use...

Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms

Science.gov (United States)

2004-06-01

clouds. Their results provide strong support for a theory that "density waves" explain how spiral arms can persist in a galaxy without winding themselves so tightly that, in effect, they disappear. The density-wave theory, proposed by Frank Shu and C.C. Lin in 1964, says that a galaxy's spiral pattern is a wave of higher density, or compression, that revolves around the galaxy at a speed different from that of the galaxy's gas and stars. Schinnerer and her colleagues studied a region in one of M51's spiral arms that presumably has just overtaken and passed through the density wave. Their data indicate that gas on the trailing edge of the spiral arm, which has most recently passed through the density wave, is both warmer and more turbulent than gas in the forward edge of the arm, which would have passed through the density wave longer ago. "This is what we would expect from the density-wave theory," Schinnerer said. "The gas that passed through the density wave earlier has had time to cool and lose the turbulence caused by the passage," she added. "Our results show, for the first time, how the density wave operates on a cloud-cloud scale, and how it promotes and prevents star formation in spiral arms," Aalto said. The next step, the scientists say, is to look at other spiral galaxies to see if a similar pattern is present. That will have to wait, Schinnerer said, because the radio emission from CO molecules that provides the information on temperature and turbulence is very faint. "When the Atacama Large Millimeter Array (ALMA) comes on line, it will have the ability to extend this type of study to other galaxies. We look forward to using ALMA to test the density-wave model more thoroughly," Schinnerer said. ALMA is a millimeter-wave observatory that will use 64, 12-meter-diameter dish antennas on the Atacama Desert of northern Chile. Now under construction, ALMA will provide astronomers with an unprecedented capability to study the Universe at millimeter wavelengths. The

Cosmological tests of modified gravity.

Science.gov (United States)

Koyama, Kazuya

2016-04-01

We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of general relativity (GR) has been tested accurately within the local universe i.e. the Solar System, but this leaves the possibility open that it is not a good description of gravity at the largest scales in the Universe. This being said, the standard model of cosmology assumes GR on all scales. In 1998, astronomers made the surprising discovery that the expansion of the Universe is accelerating, not slowing down. This late-time acceleration of the Universe has become the most challenging problem in theoretical physics. Within the framework of GR, the acceleration would originate from an unknown dark energy. Alternatively, it could be that there is no dark energy and GR itself is in error on cosmological scales. In this review, we first give an overview of recent developments in modified gravity theories including f(R) gravity, braneworld gravity, Horndeski theory and massive/bigravity theory. We then focus on common properties these models share, such as screening mechanisms they use to evade the stringent Solar System tests. Once armed with a theoretical knowledge of modified gravity models, we move on to discuss how we can test modifications of gravity on cosmological scales. We present tests of gravity using linear cosmological perturbations and review the latest constraints on deviations from the standard [Formula: see text]CDM model. Since screening mechanisms leave distinct signatures in the non-linear structure formation, we also review novel astrophysical tests of gravity using clusters, dwarf galaxies and stars. The last decade has seen a number of new constraints placed on gravity from astrophysical to cosmological scales. Thanks to on-going and future surveys, cosmological tests of gravity will enjoy another, possibly even more, exciting ten years.

The Growth of Interest in Astronomical X-Ray Polarimetry

Directory of Open Access Journals (Sweden)

Frédéric Marin

2018-03-01

Full Text Available Astronomical X-ray polarimetry was first explored in the end of the 1960s by pioneering rocket instruments. The craze arising from the first discoveries of stellar and supernova remnant X-ray polarization led to the addition of X-ray polarimeters to early satellites. Unfortunately, the inadequacy of the diffraction and scattering technologies required to measure polarization with respect to the constraints driven by X-ray mirrors and detectors, coupled with long integration times, slowed down the field for almost 40 years. Thanks to the development of new, highly sensitive, compact X-ray polarimeters in the beginning of the 2000s, observing astronomical X-ray polarization has become feasible, and scientists are now ready to explore our high-energy sky thanks to modern X-ray polarimeters. In the forthcoming years, several X-ray missions (rockets, balloons, and satellites will create new observational opportunities. Interest in astronomical X-ray polarimetry field has thus been renewed, and this paper presents for the first time a quantitative assessment, all based on scientific literature, of the growth of this interest.

Dual-Process Theories of Reasoning: The Test of Development

Science.gov (United States)

Barrouillet, Pierre

2011-01-01

Dual-process theories have become increasingly influential in the psychology of reasoning. Though the distinction they introduced between intuitive and reflective thinking should have strong developmental implications, the developmental approach has rarely been used to refine or test these theories. In this article, I review several contemporary…

The re-definition of the astronomical unit of length:reasons and consequences

Science.gov (United States)

Capitaine, Nicole; Klioner, Sergei; McCarthy, Dennis

2012-08-01

The astronomical unit (au) is a unit of length approximating the Sun - Earth distance that is used mainly to express the scale of the solar system. Its current definition is based on the value of the Gaussian gravitational constant, k. This conveniently provided accurate relative distances (expressed in astronomical units) when absolute distances could not be estimated with high accuracy. The huge improvement achieved in solar system ephemerides during the last decade provides an opportunity to re - consider the definition and status of the au. This issue was discussed recently by Klioner (2008), Capitaine & Guinot (2009) and Capitaine et al. (2011), as well as within the IAU Working Group on "Numerical Standards for Fundamental astronomy". This resulted in a proposed IAU Resolution recommending that the astronomical unit be re - defined as a fixed number of Système International d ’ Unités (SI) metres through a defining constant. For continuity that constant should be the value of the current best estimate in metres as adopted by IAU 2009 Resolution B2 (i.e. 149 597 870 700 m). After reviewing the properties of the IAU 1976 astronomical unit and its status in the IAU 2009 System of Astronomical Constants, we explain the main reasons for a change; we present and discuss the proposed new definition as well as the advantages over the historical definition. One important consequence is that the heliocentric gravitational constant, GM(Sun), would cease to have a fixed value in astronomical units and will have to be determined experimentally. This would be compliant with modern dynamics of the solar system as it would allow

THE INFRARED SPECTRA OF VERY LARGE IRREGULAR POLYCYCLIC AROMATIC HYDROCARBONS (PAHs): OBSERVATIONAL PROBES OF ASTRONOMICAL PAH GEOMETRY, SIZE, AND CHARGE

International Nuclear Information System (INIS)

Bauschlicher, Charles W.; Peeters, Els; Allamandola, Louis J.

2009-01-01

The mid-infrared (IR) spectra of six large, irregular polycyclic aromatic hydrocarbons (PAHs) with formulae (C 84 H 24 -C 120 H 36 ) have been computed using density functional theory (DFT). Trends in the dominant band positions and intensities are compared to those of large, compact PAHs as a function of geometry, size, and charge. Irregular edge moieties that are common in terrestrial PAHs, such as bay regions and rings with quartet hydrogens, are shown to be uncommon in astronomical PAHs. As for all PAHs comprised solely of C and H reported to date, mid-IR emission from irregular PAHs fails to produce a strong CC str band at 6.2 μm, the position characteristic of the important, class A astronomical PAH spectra. Earlier studies showed that inclusion of nitrogen within a PAH shifts this to 6.2 μm for PAH cations. Here we show that this band shifts to 6.3 μm in nitrogenated PAH anions, close to the position of the CC stretch in class B astronomical PAH spectra. Thus, nitrogenated PAHs may be important in all sources and the peak position of the CC stretch near 6.2 μm appears to directly reflect the PAH cation to anion ratio. Large irregular PAHs exhibit features at 7.8 μm but lack them near 8.6 μm. Hence, the 7.7 μm astronomical feature is produced by a mixture of small and large PAHs while the 8.6 μm band can only be produced by large compact PAHs. As with the CC str , the position and profile of these bands reflect the PAH cation to anion ratio.

Proposed experimental test of the theory of hole superconductivity

Energy Technology Data Exchange (ETDEWEB)

Hirsch, J.E., E-mail: jhirsch@ucsd.edu

2016-06-15

Highlights: • The conventional theory of superconductivity predicts no charge flow when the normal-superconductor phase boundary moves. • The theory of hole superconductivity predicts flow and counterflow of charge. • An experiment to measure a voltage is proposed. • No voltage will be measured if the conventional theory is correct. • A voltage will be measured if the theory of hole superconductivity is correct. - Abstract: The theory of hole superconductivity predicts that in the reversible transition between normal and superconducting phases in the presence of a magnetic field there is charge flow in direction perpendicular to the normal-superconductor phase boundary. In contrast, the conventional BCS-London theory of superconductivity predicts no such charge flow. Here we discuss an experiment to test these predictions.

Automatic astronomical coordinate determination using digital zenith cameras

Directory of Open Access Journals (Sweden)

S Farzaneh

2009-12-01

Full Text Available Celestial positioning has been used for navigation purposes for many years. Stars as the extra-terrestrial benchmarks provide unique opportunity in absolute point positioning. However, astronomical field data acquisition and data processing of the collected data is very time-consuming. The advent of the Global Positioning System (GPS nearly made the celestial positioning system obsolete. The new satellite-based positioning system has been very popular since it is very efficient and convenient for many daily life applications. Nevertheless, the celestial positioning method is never replaced by satellite-based positioning in absolute point positioning sense. The invention of electro-optical devices at the beginning of the 21st century was really a rebirth in geodetic astronomy. Today, the digital cameras with relatively high geometric and radiometric accuracy has opened a new insight in satellite attitude determination and the study of the Earth's surface geometry and physics of its interior, i.e., computation of astronomical coordinates and the vertical deflection components. This method or the so-called astrogeodetic vision-based method help us to determine astronomical coordinates with an accuracy better than 0.1 arc second. The theoretical background, an innovative transformation approach and the preliminary numerical results are addressed in this paper.

The Amateur Astronomer's Introduction to the Celestial Sphere

Science.gov (United States)

Millar, William

2005-12-01

This introduction to the night sky is for amateur astronomers who desire a deeper understanding of the principles and observations of naked-eye astronomy. It covers topics such as terrestrial and astronomical coordinate systems, stars and constellations, the relative motions of the sky, sun, moon and earth leading to an understanding of the seasons, phases of the moon, and eclipses. Topics are discussed and compared for observers located in both the northern and southern hemispheres. Written in a conversational style, only addition and subtraction are needed to understand the basic principles and a more advanced mathematical treatment is available in the appendices. Each chapter contains a set of review questions and simple exercises to reinforce the reader's understanding of the material. The last chapter is a set of self-contained observation projects to get readers started with making observations about the concepts they have learned. William Charles Millar, currently Professor of Astronomy at Grand Rapids Community College in Michigan, has been teaching the subject for almost twenty years and is very involved with local amateur astronomy groups. Millar also belongs to The Planetary Society and the Astronomical Society of the Pacific and has traveled to Europe and South America to observe solar eclipses. Millar holds a Masters degree in Physics from Western Michigan University.

Test theory of special relativity: What it is and why we need it

International Nuclear Information System (INIS)

Mansouri, R.

1988-03-01

After a critical overview on the traditional way of expressing the accuracy of experiments testing the postulates of the special theory of relativity, the four-parameter test theory is briefly introduced. The existing experiments are then classified and their accuracies are expressed in terms of the parameter of the test theory. By changing the convention of synchronization of distant clocks, it is shown how different equivalent theories can be formulated. (author). 23 refs

Climate and carbon-cycle response to astronomical forcing over the last 35 Ma.

Science.gov (United States)

De Vleeschouwer, D.; Palike, H.; Vahlenkamp, M.; Crucifix, M.

2017-12-01

On a million-year time scale, the characteristics of insolation forcing caused by cyclical variations in the astronomical parameters of the Earth remain stable. Nevertheless, Earth's climate responded very differently to this forcing during different parts of the Cenozoic. The recently-published ∂18Obenthic megasplice (De Vleeschouwer et al., 2017) allowed for a clear visualization of these changes in global climate response to astronomical forcing. However, many open questions remain regarding how carbon-cycle dynamics influence Earth's climate sensitivity to astronomical climate forcing. To provide insight into the interaction between the carbon cycle and astronomical insolation forcing, we built a benthic carbon isotope (∂13Cbenthic) megasplice for the last 35 Ma, employing the same technique used to build the ∂18Obenthic megasplice. The ∂13Cbenthic megasplice exhibits a strong imprint of the 405 and 100-kyr eccentricity cycles throughout the last 35 Ma. This is intriguing, as the oxygen isotope megasplice looses its eccentricity imprint after the mid-Miocene climatic transition (MMCT; see Fig. 1 in De Vleeschouwer et al., 2017). In other words, the carbon cycle responded completely differently to astronomical forcing, compared to global climate during the late Miocene. We visualize this difference in response by the application of a Gaussian process, which renders the dependence of one variable (here ∂18Obenthic or ∂13Cbenthic) in a multidimensional space (here precession, obliquity and eccentricity). Together, the ∂13Cbenthic and ∂18Obenthic megasplices thus provide a unique tool for paleoclimatology, allowing for the quantification and visualization of the changing paleoclimate and carbon-cycle response to astronomical forcing throughout geologic time. References De Vleeschouwer, D., Vahlenkamp, M., Crucifix, M., Pälike, H., 2017. Alternating Southern and Northern Hemisphere climate response to astronomical forcing during the past 35 m

Age-Related Differences in Goals: Testing Predictions from Selection, Optimization, and Compensation Theory and Socioemotional Selectivity Theory

Science.gov (United States)

Penningroth, Suzanna L.; Scott, Walter D.

2012-01-01

Two prominent theories of lifespan development, socioemotional selectivity theory and selection, optimization, and compensation theory, make similar predictions for differences in the goal representations of younger and older adults. Our purpose was to test whether the goals of younger and older adults differed in ways predicted by these two…

Astronomical sketching a step-by-step introduction

CERN Document Server

Handy, Richard; Perez, Jeremy; Rix, Erika; Robbins, Sol

2007-01-01

This book presents the amateur with fine examples of astronomical sketches and step-by-step tutorials in each medium, from pencil to computer graphics programs. This unique book can teach almost anyone to create beautiful sketches of celestial objects.

Astronomers Reveal Extinct Extra-Terrestrial Fusion Reactor

Science.gov (United States)

2004-06-01

improve our understanding of the life-cycle of stars.' The Chandra X-ray data also reveal the signatures of neon, an expected by-product of helium fusion. However, a big surprise was the presence of magnesium in similar quantities. This result may provide a key to the unique composition of H1504+65 and validate theoretical predictions that, if massive enough, some stars can extend their lives by tapping yet another energy source: the fusion of carbon into magnesium. However, as magnesium can also be produced by helium fusion, proof of the theory is not yet ironclad. The final link in the puzzle would be the detection of sodium, which will require data from yet another observatory: the Hubble Space Telescope. The team has already been awarded time on the Hubble Space Telescope to search for sodium in H1504+65 next year, and will, hopefully, discover the final answer as to the origin of this unique star. This work will be published in July in the 'Astronomy & Astrophysics' journal. The Chandra X-ray Observatory and the Far Ultraviolet Spectroscopic Explorer (FUSE) were both launched into orbit by NASA in 1999. Their instruments make use of a technique called spectroscopy, which spreads the light obtained from astronomical objects into its constituent X-ray and ultraviolet 'colours', in the same way visible light is dispersed into a rainbow naturally, by water droplets in the atmosphere, or artificially, by a prism. When studied in fine detail each spectrum is a unique 'fingerprint' which tells us what elements are present and reveals the physical conditions in the object being studied. Related Internet Address http://www.ras.org.uk/index.php?option=com_content&task=view&id=673&Itemid=2

Powerful Radio Burst Indicates New Astronomical Phenomenon

Science.gov (United States)

2007-09-01

Astronomers studying archival data from an Australian radio telescope have discovered a powerful, short-lived burst of radio waves that they say indicates an entirely new type of astronomical phenomenon. Region of Strong Radio Burst Visible-light (negative greyscale) and radio (contours) image of Small Magellanic Cloud and area where burst originated. CREDIT: Lorimer et al., NRAO/AUI/NSF Click on image for high-resolution file ( 114 KB) "This burst appears to have originated from the distant Universe and may have been produced by an exotic event such as the collision of two neutron stars or the death throes of an evaporating black hole," said Duncan Lorimer, Assistant Professor of Physics at West Virginia University (WVU) and the National Radio Astronomy Observatory (NRAO). The research team led by Lorimer consists of Matthew Bailes of Swinburne University in Australia, Maura McLaughlin of WVU and NRAO, David Narkevic of WVU, and Fronefield Crawford of Franklin and Marshall College in Lancaster, Pennsylvania. The astronomers announced their findings in the September 27 issue of the online journal Science Express. The startling discovery came as WVU undergraduate student David Narkevic re-analyzed data from observations of the Small Magellanic Cloud made by the 210-foot Parkes radio telescope in Australia. The data came from a survey of the Magellanic Clouds that included 480 hours of observations. "This survey had sought to discover new pulsars, and the data already had been searched for the type of pulsating signals they produce," Lorimer said. "We re-examined the data, looking for bursts that, unlike the usual ones from pulsars, are not periodic," he added. The survey had covered the Magellanic Clouds, a pair of small galaxies in orbit around our own Milky Way Galaxy. Some 200,000 light-years from Earth, the Magellanic Clouds are prominent features in the Southern sky. Ironically, the new discovery is not part of these galaxies, but rather is much more distant

The Hunt for Pristine Cretaceous Astronomical Rhythms at Demerara Rise (Cenomanian-Coniacian)

Science.gov (United States)

Ma, C.; Meyers, S. R.

2014-12-01

Rhythmic Upper Cretaceous strata from Demerara Rise (ODP leg 207) preserve a strong astronomical signature, and this attribute has facilitated the development of continuous astrochronologies to refine the geologic time scale and calibrate Late Cretaceous biogeochemical events. While the mere identification of astronomical rhythms is a crucial first step in many deep-time paleoceanographic investigations, accurate evaluation of often subtle amplitude and frequency modulations are required to: (1) robustly constrain the linkage between climate and sedimentation, and (2) evaluate the plausibility of different theoretical astrodynamical models. The availability of a wide range of geophysical, lithologic and geochemical data from multiple sites drilled at Demerara Rise - when coupled with recent innovations in the statistical analysis of cyclostratigraphic data - provides an opportunity to hunt for the most pristine record of Cretaceous astronomical rhythms at a tropical Atlantic location. To do so, a statistical metric is developed to evaluate the "internal" consistency of hypothesized astronomical rhythms observed in each data set, particularly with regard to the expected astronomical amplitude modulations. In this presentation, we focus on how the new analysis yields refinements to the existing astrochronologies, provides constraints on the linkages between climate and sedimentation (including the deposition of organic carbon-rich sediments at Demerara Rise), and allows a quantitative evaluation of the continuity of deposition across sites at multiple temporal scales.

Analysis of North Korea's Nuclear Tests under Prospect Theory

International Nuclear Information System (INIS)

Lee, Han Myung; Ryu, Jae Soo; Lee, Kwang Seok; Lee, Dong Hoon; Jun, Eunju; Kim, Mi Jin

2013-01-01

North Korea has chosen nuclear weapons as the means to protect its sovereignty. Despite international society's endeavors and sanctions to encourage North Korea to abandon its nuclear ambition, North Korea has repeatedly conducted nuclear testing. In this paper, the reason for North Korea's addiction to a nuclear arsenal is addressed within the framework of cognitive psychology. The prospect theory addresses an epistemological approach usually overlooked in rational choice theories. It provides useful implications why North Korea, being under a crisis situation has thrown out a stable choice but taken on a risky one such as nuclear testing. Under the viewpoint of prospect theory, nuclear tests by North Korea can be understood as follows: The first nuclear test in 2006 is seen as a trial to escape from loss areas such as financial sanctions and regime threats; the second test in 2009 was interpreted as a consequence of the strategy to recover losses by making a direct confrontation against the United States; and the third test in 2013 was understood as an attempt to strengthen internal solidarity after Kim Jong-eun inherited the dynasty, as well as to enhance bargaining power against the United States. Thus, it can be summarized that Pyongyang repeated its nuclear tests to escape from a negative domain and to settle into a positive one. In addition, in the future, North Korea may not be willing to readily give up its nuclear capabilities to ensure the survival of its own regime

Astronomical fire: Richard Carrington and the solar flare of 1859.

Science.gov (United States)

Clark, Stuart

2007-09-01

An explosion on the Sun in 1859, serendipitously witnessed by amateur astronomer Richard Carrington, plunged telegraphic communications into chaos and bathed two thirds of the Earth's skies in aurorae. Explaining what happened to the Sun and how it could affect Earth, 93 million miles away, helped change the direction of astronomy. From being concerned principally with charting the stars to aid navigation, astronomers became increasingly concerned with what the celestial objects were, how they behaved and how they might affect life on Earth.

Twenty five years of fundamental theory

International Nuclear Information System (INIS)

Bell, J.S.

1980-01-01

In reviewing the last twenty five years in fundamental physics theory it is stated that there has been no revolution in this field. In the absence of gravitation, Lorentz invariance remains a requirement on fundamental laws. Einstein's theory of gravitation inspires increasing conviction on the astronomical scale. Quantum theory remains the framework for all serious effort in microphysics, and quantum electrodynamics remains the model of a fully articulated microphysical theory, completely successful in its domain. However,a number of ideas have appeared, of great theoretical interest and some phenomenological success, which may well contribute to the next decisive step. Recent work on the following topics is mentioned; gravitational radiation, singularites, black body radiation from black holes, gauge and hidden symmetry in quantum electrodynamics, the renormalization of electromagnetic and weak interaction theory, non-Abelian gauge theories, magnetic monopoles as the most striking example of solitons, and supersymmetry. (UK)

Using Classical Test Theory and Item Response Theory to Evaluate the LSCI

Science.gov (United States)

Schlingman, Wayne M.; Prather, E. E.; Collaboration of Astronomy Teaching Scholars CATS

2011-01-01

Analyzing the data from the recent national study using the Light and Spectroscopy Concept Inventory (LSCI), this project uses both Classical Test Theory (CTT) and Item Response Theory (IRT) to investigate the LSCI itself in order to better understand what it is actually measuring. We use Classical Test Theory to form a framework of results that can be used to evaluate the effectiveness of individual questions at measuring differences in student understanding and provide further insight into the prior results presented from this data set. In the second phase of this research, we use Item Response Theory to form a theoretical model that generates parameters accounting for a student's ability, a question's difficulty, and estimate the level of guessing. The combined results from our investigations using both CTT and IRT are used to better understand the learning that is taking place in classrooms across the country. The analysis will also allow us to evaluate the effectiveness of individual questions and determine whether the item difficulties are appropriately matched to the abilities of the students in our data set. These results may require that some questions be revised, motivating the need for further development of the LSCI. This material is based upon work supported by the National Science Foundation under Grant No. 0715517, a CCLI Phase III Grant for the Collaboration of Astronomy Teaching Scholars (CATS). Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

All-sky brightness monitoring of light pollution with astronomical methods.

Science.gov (United States)

Rabaza, O; Galadí-Enríquez, D; Estrella, A Espín; Dols, F Aznar

2010-06-01

This paper describes a mobile prototype and a protocol to measure light pollution based on astronomical methods. The prototype takes three all-sky images using BVR filters of the Johnson-Cousins astronomical photometric system. The stars are then identified in the images of the Hipparcos and General Catalogue of Photometric Data II astronomical catalogues, and are used as calibration sources. This method permits the measurement of night-sky brightness and facilitates an estimate of which fraction is due to the light up-scattered in the atmosphere by a wide variety of man-made sources. This is achieved by our software, which compares the sky background flux to that of many stars of known brightness. The reduced weight and dimensions of the prototype allow the user to make measurements from virtually any location. This prototype is capable of measuring the sky distribution of light pollution, and also provides an accurate estimate of the background flux at each photometric band. (c) 2010 Elsevier Ltd. All rights reserved.

Astronomical Signatures of Dark Matter

Directory of Open Access Journals (Sweden)

Paul Gorenstein

2014-01-01

Full Text Available Several independent astronomical observations in different wavelength bands reveal the existence of much larger quantities of matter than what we would deduce from assuming a solar mass to light ratio. They are very high velocities of individual galaxies within clusters of galaxies, higher than expected rotation rates of stars in the outer regions of galaxies, 21 cm line studies indicative of increasing mass to light ratios with radius in the halos of spiral galaxies, hot gaseous X-ray emitting halos around many elliptical galaxies, and clusters of galaxies requiring a much larger component of unseen mass for the hot gas to be bound. The level of gravitational attraction needed for the spatial distribution of galaxies to evolve from the small perturbations implied by the very slightly anisotropic cosmic microwave background radiation to its current web-like configuration requires much more mass than is observed across the entire electromagnetic spectrum. Distorted shapes of galaxies and other features created by gravitational lensing in the images of many astronomical objects require an amount of dark matter consistent with other estimates. The unambiguous detection of dark matter and more recently evidence for dark energy has positioned astronomy at the frontier of fundamental physics as it was in the 17th century.

The League of Astronomers: Outreach

Science.gov (United States)

Paat, Anthony; Brandel, A.; Schmitz, D.; Sharma, R.; Thomas, N. H.; Trujillo, J.; Laws, C. S.; Astronomers, League of

2014-01-01

The University of Washington League of Astronomers (LOA) is an organization comprised of University of Washington (UW) undergraduate students. Our main goal is to share our interest in astronomy with the UW community and with the general public. The LOA hosts star parties on the UW campus and collaborates with the Seattle Astronomical Society (SAS) on larger Seattle-area star parties. At the star parties, we strive to teach our local community about what they can view in our night sky. LOA members share knowledge of how to locate constellations and use a star wheel. The relationship the LOA has with members of SAS increases both the number of events and people we are able to reach. Since the cloudy skies of the Northwest prevent winter star parties, we therefore focus our outreach on the UW Mobile Planetarium, an inflatable dome system utilizing Microsoft’s WorldWide Telescope (WWT) software. The mobile planetarium brings astronomy into the classrooms of schools unable to travel to the UW on-campus planetarium. Members of the LOA volunteer their time towards this project and we make up the majority of the Mobile Planetarium volunteers. Our outreach efforts allow us to connect with the community and enhance our own knowledge of astronomy.

Astronomers in the Chemist's War

Science.gov (United States)

Trimble, Virginia L.

2012-01-01

World War II, with radar, rockets, and "atomic" bombs was the physicists' war. And many of us know, or think we know, what our more senior colleagues did during it, with Hubble and Hoffleit at Aberdeen; M. Schwarzschild on active duty in Italy; Bondi, Gold, and Hoyle hunkered down in Dunsfeld, Surrey, talking about radar, and perhaps steady state; Greenstein and Henyey designing all-sky cameras; and many astronomers teaching navigation. World War I was The Chemists' War, featuring poison gases, the need to produce liquid fuels from coal on one side of the English Channel and to replace previously-imported dyesstuffs on the other. The talke will focus on what astronomers did and had done to them between 1914 and 1919, from Freundlich (taken prisoner on an eclipse expedition days after the outbreak of hostilities) to Edwin Hubble, returning from France without ever having quite reached the front lines. Other events bore richer fruit (Hale and the National Research Council), but very few of the stories are happy ones. Most of us have neither first nor second hand memories of The Chemists' War, but I had the pleasure of dining with a former Freundlich student a couple of weeks ago.

Astronomical Instrumentation Systems Quality Management Planning: AISQMP (Abstract)

Science.gov (United States)

Goldbaum, J.

2017-12-01

(Abstract only) The capability of small aperture astronomical instrumentation systems (AIS) to make meaningful scientific contributions has never been better. The purpose of AIS quality management planning (AISQMP) is to ensure the quality of these contributions such that they are both valid and reliable. The first step involved with AISQMP is to specify objective quality measures not just for the AIS final product, but also for the instrumentation used in its production. The next step is to set up a process to track these measures and control for any unwanted variation. The final step is continual effort applied to reducing variation and obtaining measured values near optimal theoretical performance. This paper provides an overview of AISQMP while focusing on objective quality measures applied to astronomical imaging systems.

Validity Theory: Reform Policies, Accountability Testing, and Consequences

Science.gov (United States)

Chalhoub-Deville, Micheline

2016-01-01

Educational policies such as Race to the Top in the USA affirm a central role for testing systems in government-driven reform efforts. Such reform policies are often referred to as the global education reform movement (GERM). Changes observed with the GERM style of testing demand socially engaged validity theories that include consequential…

Astronomers Get Closest Look Yet At Milky Way's Mysterious Core

Science.gov (United States)

2005-11-01

those in our latest images," said Fred K.Y. Lo, Director of the National Radio Astronomy Observatory and another member of the research team. "Seeing that shadow would be the final proof that a supermassive black hole is at the center of our Galaxy," Lo added. Many galaxies are believed to have supermassive black holes at their centers, and many of these are much more massive than the Milky Way's black hole. The Milky Way's central black hole is much less active than that of many other galaxies, presumably because it has less nearby material to "eat." Astronomers believe that the radio waves they see coming from Sagittarius A* are either generated by particle jets that have been detected in many more-active galaxies or from accretion flows that are spiraling into the central black hole. By observing the object at higher radio frequencies, scientists have detected a region of radiation ever closer to the black hole. The results announced last year were based on observations at 43 GigaHertz (GHz), and the latest observations were made at 86 GHz. "We believe that if we can double the frequency again, we will see the black-hole shadow produced by effects of Einstein's General Relativity theory," Lo said. In a few years, when the Atacama Large Millimeter Array (ALMA) comes on line, it may be used in conjunction with other millimeter-wave telescopes to make the higher-frequency observations that will reveal the telltale black-hole shadow. At a distance of 26,000 light-years, the Milky Way's central black hole is the closest such supermassive object. That makes it the most likely one to finally reveal the concrete evidence for a black hole that astronomers have sought for years. Shen and Lo worked with Mao-Chang Liang of Caltech, Paul Ho of the Harvard-Smithsonian Center for Astrophysics (CfA) and the Institute of Astronomy & Astrophysics of the Academia Sinica in Taiwan, and Jun-Hui Zhao of CfA. The astronomers published their findings in the November 3 issue of the

The Mie Theory Basics and Applications

CERN Document Server

Wriedt, Thomas

2012-01-01

This book presents in a concise way the Mie theory and its current applications. It begins with an overview of current theories, computational methods, experimental techniques, and applications of optics of small particles. There is also some biographic information on Gustav Mie, who published his famous paper on the colour of Gold colloids in 1908. The Mie solution for the light scattering of small spherical particles set the basis for more advanced scattering theories and today there are many methods to calculate light scattering and absorption for practically any shape and composition of particles. The optics of small particles is of interest in industrial, atmospheric, astronomic and other research. The book covers the latest developments in divers fields in scattering theory such as plasmon resonance, multiple scattering and optical force.

Astronomical chemistry.

Science.gov (United States)

Klemperer, William

2011-01-01

The discovery of polar polyatomic molecules in higher-density regions of the interstellar medium by means of their rotational emission detected by radioastronomy has changed our conception of the universe from essentially atomic to highly molecular. We discuss models for molecule formation, emphasizing the general lack of thermodynamic equilibrium. Detailed chemical kinetics is needed to understand molecule formation as well as destruction. Ion molecule reactions appear to be an important class for the generally low temperatures of the interstellar medium. The need for the intrinsically high-quality factor of rotational transitions to definitively pin down molecular emitters has been well established by radioastronomy. The observation of abundant molecular ions both positive and, as recently observed, negative provides benchmarks for chemical kinetic schemes. Of considerable importance in guiding our understanding of astronomical chemistry is the fact that the larger molecules (with more than five atoms) are all organic.

"She is an astronomer" in Spain; the International Year of Astronomy 2009 and beyond

Science.gov (United States)

Márquez, I.

2011-11-01

The work of the Spanish node for the IYA2009 Cornerstoneproject, "She is an Astronomer" is presented. Our team developedseveral projects with the common goal of promoting gender equality andwomen participation in professional and amateur astronomy, andsupporting the training of young women researchers andtechnologists. The main ones were: 1)Calendar "Women astronomerswho made history". We highlighted exceptional women, fromdifferent epochs and countries, whose contributions to theadvancement of science deserve to transcend anonymity and occupy aplace in history.2) "Women in the stars" was a series of 8 TV programsdevoted to the contribution of Spanish women astronomers, made incollaboration with the UNED.3) "Women in Spanish Astronomy: analysis of a peculiar situation: A universe to discover", was the first sociological study of this type, including quantitative and qualitative (individual and group interviews) analyses. 4) The exhibit "She Astronomer", was aimed at teaching astronomy from a new perspective: the relevant contributions by women astronomers from different times and places.The main aims of the "Commission for Women and Astronomy",recently created within the Spanish Astronomical Society (SEA), are alsodescribed.

The caracol tower at chichen itza: an ancient astronomical observatory?

Science.gov (United States)

Aveni, A F; Gibbs, S L; Hartung, H

1975-06-06

Although our investigations reveal a number of significant astronomical events coinciding with many of the measured alignments presented in Table 1, not every alignment appears to have an astronomical match which we can recognize. It may be that only some of the sighting possibilities we have discussed were actually functional. Moreover, our search of significant astronomical events to match the alignments has included only those which seem of obvious functional importance to us: sun, moon, and planetary extremes and the setting positions of the brightest stars. We have emphasized those celestial bodies which are documented in the literature as having been of importance. Perhaps hitherto unrecognized constellations were sighted in the windows, perhaps fainter stars, the heliacal rising and setting times of which could have served to mark important dates in the calendar. While we propose no grand cosmic scheme for the astronomical design of the Caracol it can be inferred that the building, apart from being a monument related to Quetzalcoatl, was erected primarily for the purpose of embodying in its architecture certain significant astronomical event alignments, in the same sense that a modern astronomical ephemeris exhibits information of importance to us in the keeping of the current calendar. There are examples in the Mesoamerican historical literature of deliberate attempts to align buildings with astronomical directions of importance. For example, Maudslay (33) quotes Father Motolinia, who tells us that in Tenochtitlan the festival called Tlacaxipeualistli "took place when the sun stood in the middle of Huicholobos, which was at the equinox, and because it was a little out of the straight, Montezuma wished to pull it down and set it right." According to Maudslay, worshipers were probably facing east to watch the sun rise between the two oratories on the Great Temple of Tenochtitlan at the time of the equinox. The directions of the faces of the Lower and Upper

Astronomical Research Institute Photometric Results

Science.gov (United States)

Linder, Tyler R.; Sampson, Ryan; Holmes, Robert

2013-01-01

The Astronomical Research Institute (ARI) conducts astrometric and photometric studies of asteroids with a concentration on near-Earth objects (NEOs). A 0.76-m autoscope was used for photometric studies of seven asteroids of which two were main-belt targets and five were NEOs, including one potentially hazardous asteroid (PHA). These objects are: 3122 Florence, 3960 Chaliubieju, 5143 Heracles, (6455) 1992 HE, (36284) 2000 DM8, (62128) 2000 SO1, and 2010 LF86.

The Undergraduate Research Resources at the Pisgah Astronomical Research Institute

Science.gov (United States)

Cline, J. Donald; Castelaz, Michael W.

2016-01-01

Pisgah Astronomical Research Institute (PARI), a former NASA tracking station located in western North Carolina, has been offering programs, campus, and instrument use for undergraduate research and learning experiences since 2000. Over these years, PARI has collaborated with universities and colleges in the Southeastern U.S. Sharing its campus with institutions of higher learning is a priority for PARI as part of its mission to "to providing hands-on educational and research opportunities for a broad cross-section of users in science, technology, engineering and math (STEM) disciplines."PARI is a 200 acre campus for environmental, earth, geological, physical, and astronomical sciences. For example, the PARI 26-m and 4.6-m radio telescopes are excellent for teaching electromagnetic theory, spectroscopy, atomic and molecular emission processes, and general physics and astronomy concepts. The PARI campus has lab and office space, data centers with high speed internet, distance learning capabilities, radio and optical telescopes, earth science sensors, housing and cafeteria.Also, the campus is in an excellent spot for environmental and biological sciences lab and classroom experiences for students. The campus has the capability to put power and Internet access almost anywhere on its 200 acre campus so experiments can be set up in a protected area of a national forest. For example, Earthscope operates a Plate Boundary Observatory sensor on campus to measure plate tectonic motion. And, Clemson University has an instrument measuring winds and temperatures in the Thermsophere. The use of thePARI campus is limited only by the creativity faculty to provide a rich educational environment for their students. An overview of PARI will be presented along with a summary of programs, and a summary of undergraduate research experiences over the past 15 years. Access to PARI and collaboration possibilities will be presented.

Resolution of a cosmological paradox using concepts from general relativity theory

International Nuclear Information System (INIS)

Silverman, A.N.

1986-01-01

According to the big bang theory, the universe began about 15 billion years ago and has been continually expanding ever since. If certain elementary physical concepts are naively applied to this cosmological theory, it can lead to a paradox in which distant astronomical objects seem to have lain at distances from the Earth larger than the possible size of the universe. The paradox is resolved by using concepts from general relativity theory. These concepts may appear startling to some readers

Adapting astronomical source detection software to help detect animals in thermal images obtained by unmanned aerial systems

Science.gov (United States)

Longmore, S. N.; Collins, R. P.; Pfeifer, S.; Fox, S. E.; Mulero-Pazmany, M.; Bezombes, F.; Goodwind, A.; de Juan Ovelar, M.; Knapen, J. H.; Wich, S. A.

2017-02-01

In this paper we describe an unmanned aerial system equipped with a thermal-infrared camera and software pipeline that we have developed to monitor animal populations for conservation purposes. Taking a multi-disciplinary approach to tackle this problem, we use freely available astronomical source detection software and the associated expertise of astronomers, to efficiently and reliably detect humans and animals in aerial thermal-infrared footage. Combining this astronomical detection software with existing machine learning algorithms into a single, automated, end-to-end pipeline, we test the software using aerial video footage taken in a controlled, field-like environment. We demonstrate that the pipeline works reliably and describe how it can be used to estimate the completeness of different observational datasets to objects of a given type as a function of height, observing conditions etc. - a crucial step in converting video footage to scientifically useful information such as the spatial distribution and density of different animal species. Finally, having demonstrated the potential utility of the system, we describe the steps we are taking to adapt the system for work in the field, in particular systematic monitoring of endangered species at National Parks around the world.

``Orion, I Don't Love You'': The Astronomical Legacy of Carl Sandburg

Science.gov (United States)

Ricca, B.

2013-04-01

Can poetry provide an accurate means of representing the scientific universe? This paper looks at the astronomical poetry of Carl Sandburg and how the poet employs a scientific framework to deepen his work. Sandburg's method is then compared to a class project of middle school students who use his poetry (and their own) to learn and understand astronomical facts.

The Production Rate and Employment of Ph.D. Astronomers

Science.gov (United States)

Metcalfe, Travis S.

2008-02-01

In an effort to encourage self-regulation of the astronomy job market, I examine the supply of, and demand for, astronomers over time. On the supply side, I document the production rate of Ph.D. astronomers from 1970 to 2006 using the UMI Dissertation Abstracts database, along with data from other independent sources. I compare the long-term trends in Ph.D. production with federal astronomy research funding over the same time period, and I demonstrate that additional funding is correlated with higher subsequent Ph.D. production. On the demand side, I monitor the changing patterns of employment using statistics about the number and types of jobs advertised in the AAS Job Register from 1984 to 2006. Finally, I assess the sustainability of the job market by normalizing this demand by the annual Ph.D. production. The most recent data suggest that there are now annual advertisements for about one postdoctoral job, half a faculty job, and half a research/support position for every new domestic Ph.D. recipient in astronomy and astrophysics. The average new astronomer might expect to hold up to 3 jobs before finding a steady position.

Generalizability Theory and Classical Test Theory

Science.gov (United States)

Brennan, Robert L.

2011-01-01

Broadly conceived, reliability involves quantifying the consistencies and inconsistencies in observed scores. Generalizability theory, or G theory, is particularly well suited to addressing such matters in that it enables an investigator to quantify and distinguish the sources of inconsistencies in observed scores that arise, or could arise, over…

Threshold Theory Tested in an Organizational Setting

DEFF Research Database (Denmark)

Christensen, Bo T.; Hartmann, Peter V. W.; Hedegaard Rasmussen, Thomas

2017-01-01

A large sample of leaders (N = 4257) was used to test the link between leader innovativeness and intelligence. The threshold theory of the link between creativity and intelligence assumes that below a certain IQ level (approximately IQ 120), there is some correlation between IQ and creative...... potential, but above this cutoff point, there is no correlation. Support for the threshold theory of creativity was found, in that the correlation between IQ and innovativeness was positive and significant below a cutoff point of IQ 120. Above the cutoff, no significant relation was identified, and the two...... correlations differed significantly. The finding was stable across distinct parts of the sample, providing support for the theory, although the correlations in all subsamples were small. The findings lend support to the existence of threshold effects using perceptual measures of behavior in real...

Polishers around the globe: an overview on the market of large astronomical mirrors

Science.gov (United States)

Döhring, Thorsten

2014-07-01

Astronomical mirrors are key elements in modern optical telescopes, their dimensions are usually large and their specifications are demanding. Only a limited number of skilled companies respectively institutions around the world are able to master the challenge to polish an individual astronomical mirror, especially in dimensions above one meter. This paper presents an overview on the corresponding market including a listing of polishers around the globe. Therefore valuable information is provided to the astronomical community: Polishers may use the information as a global competitor database, astronomers and project managers may get more transparency on potential suppliers, and suppliers of polishing equipment may learn about unknown potential customers in other parts of the world. An evaluation of the historical market demand on large monolithic astronomical mirrors is presented. It concluded that this is still a niche market with a typical mean rate of 1-2 mirrors per year. Polishing of such mirrors is an enabling technology with impact on the development of technical know-how, public relation, visibility and reputation of the supplier. Within a corresponding technical discussion different polishing technologies are described. In addition it is demonstrated that strategic aspects and political considerations are influencing the selection of the optical finisher.

Testing ‘cultural reproduction theory’ against relative risk aversion theory – some remarks

DEFF Research Database (Denmark)

Munk, Martin David; Jakobsen, Anders

2015-01-01

of the concept of habitus. Our point is that blinding out the important concept of habitus amputates the theory, and that a test built upon this limitation is not a test of Bourdieu’s theory as a whole, but rather a straw man construction ignoring important parts of the theory. This has strong implications when......The aim of this research note is to discuss inherent limitations in certain established, but problematic, conventions for operationalizing and testing Pierre Bourdieu’s theory of cultural reproduction. These conventions entail a selective focus on the concept of capital at the expense...... seeking to test statistically the viability of Bourdieu’s theory, particularly vis-a-vis rational choice alternatives, and especially where these limitations are not adequately reflected in the interpretation of results and in conclusions....

Science Initiatives of the US Virtual Astronomical Observatory

Science.gov (United States)

Hanisch, R. J.

2012-09-01

The United States Virtual Astronomical Observatory program is the operational facility successor to the National Virtual Observatory development project. The primary goal of the US VAO is to build on the standards, protocols, and associated infrastructure developed by NVO and the International Virtual Observatory Alliance partners and to bring to fruition a suite of applications and web-based tools that greatly enhance the research productivity of professional astronomers. To this end, and guided by the advice of our Science Council (Fabbiano et al. 2011), we have focused on five science initiatives in the first two years of VAO operations: 1) scalable cross-comparisons between astronomical source catalogs, 2) dynamic spectral energy distribution construction, visualization, and model fitting, 3) integration and periodogram analysis of time series data from the Harvard Time Series Center and NASA Star and Exoplanet Database, 4) integration of VO data discovery and access tools into the IRAF data analysis environment, and 5) a web-based portal to VO data discovery, access, and display tools. We are also developing tools for data linking and semantic discovery, and have a plan for providing data mining and advanced statistical analysis resources for VAO users. Initial versions of these applications and web-based services are being released over the course of the summer and fall of 2011, with further updates and enhancements planned for throughout 2012 and beyond.

Science Initiatives of the US Virtual Astronomical Observatory

Directory of Open Access Journals (Sweden)

Hanisch Robert J.

2012-09-01

Full Text Available The United States Virtual Astronomical Observatory program is the operational facility successor to the National Virtual Observatory development project. The primary goal of the US VAO is to build on the standards, protocols, and associated infrastructure developed by NVO and the International Virtual Observatory Alliance partners and to bring to fruition a suite of applications and web-based tools that greatly enhance the research productivity of professional astronomers. To this end, and guided by the advice of our Science Council (advisory committee, we are focusing on five science initiatives in the first two years of VAO operations: (1 scalable cross-comparisons between astronomical source catalogs, (2 dynamic spectral energy distribution construction, visualization, and model fitting, (3 integration and periodogram analysis of time series data from the Harvard Time Series Center and NASA Star and Exoplanet Database, (4 integration of VO data discovery and access tools into the IR AF data analysis environment, and (5 a web-based portal to VO data discovery, access, and display tools. We are also developing tools for data linking and semantic discovery, and have a plan for providing data mining and advanced statistical analysis resources for VAO users. Initial versions of these applications and web-based services are being released over the course of the summer and fall of 2011, with further updates and enhancements planned for throughout 2012 and beyond.

A history of chaos theory.

Science.gov (United States)

Oestreicher, Christian

2007-01-01

Whether every effect can be precisely linked to a given cause or to a list of causes has been a matter of debate for centuries, particularly during the 17th century, when astronomers became capable of predicting the trajectories of planets. Recent mathematical models applied to physics have included the idea that given phenomena cannot be predicted precisely, although they can be predicted to some extent, in line with the chaos theory. Concepts such as deterministic models, sensitivity to initial conditions, strange attractors, and fractal dimensions are inherent to the development of this theory A few situations involving normal or abnormal endogenous rhythms in biology have been analyzed following the principles of chaos theory. This is particularly the case with cardiac arrhythmias, but less so with biological clocks and circadian rhythms.

A history of chaos theory

Science.gov (United States)

Oestreicher, Christian

2007-01-01

Whether every effect can be precisely linked to a given cause or to a list of causes has been a matter of debate for centuries, particularly during the 17th century when astronomers became capable of predicting the trajectories of planets. Recent mathematical models applied to physics have included the idea that given phenomena cannot be predicted precisely although they can be predicted to some extent in line with the chaos theory Concepts such as deterministic models, sensitivity to initial conditions, strange attractors, and fractal dimensions are inherent to the development of this theory, A few situations involving normal or abnormal endogenous rhythms in biology have been analyzed following the principles of chaos theory This is particularly the case with cardiac arrhythmias, but less so with biological clocks and circadian rhythms. PMID:17969865

Eighth Scientific Meeting of the Spanish Astronomical Society

CERN Document Server

Diego, Jose M; González-Serrano, J. Ignacio; Gorgas, Javier; Highlights of Spanish Astrophysics V

2010-01-01

This volume collects the invited contributions and plenary sessions presented at the Eighth Scientific Meeting of the Spanish Astronomical Society (Sociedad Española de Astronomía, SEA) held on July 7-11, 2008 in Santander. These contributions cover all fields of astronomy and astrophysics, i.e., the Sun and solar system, the galaxy and its components, galaxies and cosmology, observatories and instrumentation, as well as astronomy teaching and dissemination. Further plenary sessions were devoted to selected hot topics, including the exploration of the solar system, gravitational lensing, exoplanets, X-ray binaries, solar magnetism, gravitational waves, the ALHAMBRA collaboration, and the OSIRIS instrument on the new 10-m GTC. Abstracts of the contributions presented at the parallels sessions and posters are also included in the book. Complete versions of those papers are available online.

Emerging technology for astronomical optics metrology

Science.gov (United States)

Trumper, Isaac; Jannuzi, Buell T.; Kim, Dae Wook

2018-05-01

Next generation astronomical optics will enable science discoveries across all fields and impact the way we perceive the Universe in which we live. To build these systems, optical metrology tools have been developed that push the boundary of what is possible. We present a summary of a few key metrology technologies that we believe are critical for the coming generation of optical surfaces.

Astronomical and Atmospheric Observations in the Anglo-Saxon Chronicle and in Bede

Science.gov (United States)

Härke, H.

2012-01-01

Textual sources of the early Middle Ages (fifth to tenth centuries AD) contain more astronomical observations than is popularly assumed. The Anglo-Saxon Chronicle lists some 40 observations of astronomical and atmospheric events for the just over 600 years it covers. But the contexts in which these are set show that eclipses, comets, meteor showers and aurorae were seen as portents of evil events, not as objects of early scientific curiosity. The case of Bede in the early eighth century shows that this was true, to an extent, even for the educated ecclesiastical elite. BedeÕs eclipse records also appear to show that astronomical events could be used to explain unusual phenomena such as the postulated volcanic Ôdust-veilÕ event of AD 536.

The first astronomical hypothesis based on cinematographical observations: Costa Lobo's 1912 evidence for polar flattening of the moon

Science.gov (United States)

Bonifácio, Vitor; Malaquias, Isabel; Fernandes, João

2010-07-01

Acceptance by the scientific community of results obtained with new technology can be a complex process. A particularly good example is provided by the unexpected hypothesis raised by Francisco Miranda da Costa Lobo upon examination of the cinematographic film obtained during the solar eclipse of 17 April 1912. Contrary to contemporary practice this eclipse was eagerly awaited in view of its astrometrical rather than astrophysical scientific interest. The observation of this hybrid eclipse provided, in theory, a good opportunity to improve several astrometric parameters, and in particular the Moon's apparent diameter. Observations were performed from Portugal to Russia and, for the first time, movie cameras were widely deployed to register astronomical phenomena. Upon analysing the film obtained at Ovar (Portugal), Costa Lobo realised that during totality Baily's Beads were not symmetrically distributed around the Moon. As an explanation and opposing current belief he proposed a lunar flattening in the range 1/1156 to 1/380. Initially other eclipse observers supported Costa Lobo's claim. In particular, Father Willaert obtained a flattening value of 1/2050 from his cinematographic film taken at Namur (Belgium). However, these results were quickly disregarded by the international astronomical community which favoured an explanation based upon the irregularities of the lunar profile. In this paper we recall the characteristics of the 17 April 1912 eclipse and the cinematographic observations, and review the results obtained. We conclude that the lack of attention paid by the astronomical community to the new cinematographical results and Camille Flammarion's superficial analysis of the data were instrumental in the rejection of Costa Lobo's hypothesis.

A new reference frame for astronomically-tuned Plio-Pleistocene climate variability derived from a benthic oxygen isotope splice of the Mediterranean

Science.gov (United States)

Lourens, L. J.; Ziegler, M.; Konijnendijk, T. Y. M.; Hilgen, F. J.; Bos, R.; Beekvelt, B.; van Loevezijn, A.; Collin, S.

2017-12-01

The astronomical theory of climate has revolutionized our understanding of past climate change and the development of highly accurate geologic time scales for the entire Cenozoic. Most of this understanding has come from the construction of astronomically tuned global ocean benthic foraminiferal oxygen isotope (δ18O) stacked record, derived by the international drilling operations of DSDP, ODP and IODP. The tuning includes fixed phase relationships between the obliquity and precession cycles and the inferred high-latitude climate, i.e. glacial-interglacial, response, which hark back to SPECMAP, using simple ice sheet models and a limited number of radiometric dates. This approach was largely implemented in the widely applied LR04 stack, though LR04 assumed shorter response times for the smaller ice caps during the Pliocene. In the past decades, an astronomically calibrated time scale for the Pliocene and Pleistocene of the Mediterranean has been developed, which has become the reference for the standard Geologic Time Scale. Typical of the Mediterranean marine sediments are the cyclic lithological alternations, reflecting the interference between obliquity and precession-paced low latitude climate variability, such as the African monsoon. Here we present the first benthic foraminiferal based oxygen isotope record of the Mediterranean reference scale, which strikingly mirrors the LR04. We will use this record to discuss the assumed open ocean glacial-interglacial related phase relations over the past 5.3 million years.

Database retrieval systems for nuclear and astronomical data

International Nuclear Information System (INIS)

Suda, Takuma; Korennov, Sergei; Otuka, Naohiko; Yamada, Shimako; Katsuta, Yutaka; Ohnishi, Akira; Kato, Kiyoshi; Fujimoto, Masayuki Y.

2006-01-01

Data retrieval and plot systems of nuclear and astronomical data are constructed on a common platform. Web-based systems will soon be opened to the users of both fields of nuclear physics and astronomy. (author)

Astronomical tunings of the Oligocene-Miocene transition from Pacific Ocean Site U1334 and implications for the carbon cycle

Science.gov (United States)

Beddow, Helen M.; Liebrand, Diederik; Wilson, Douglas S.; Hilgen, Frits J.; Sluijs, Appy; Wade, Bridget S.; Lourens, Lucas J.

2018-03-01

Astronomical tuning of sediment sequences requires both unambiguous cycle pattern recognition in climate proxy records and astronomical solutions, as well as independent information about the phase relationship between these two. Here we present two different astronomically tuned age models for the Oligocene-Miocene transition (OMT) from Integrated Ocean Drilling Program Site U1334 (equatorial Pacific Ocean) to assess the effect tuning has on astronomically calibrated ages and the geologic timescale. These alternative age models (roughly from ˜ 22 to ˜ 24 Ma) are based on different tunings between proxy records and eccentricity: the first age model is based on an aligning CaCO3 weight (wt%) to Earth's orbital eccentricity, and the second age model is based on a direct age calibration of benthic foraminiferal stable carbon isotope ratios (δ13C) to eccentricity. To independently test which tuned age model and associated tuning assumptions are in best agreement with independent ages based on tectonic plate-pair spreading rates, we assign the tuned ages to magnetostratigraphic reversals identified in deep-marine magnetic anomaly profiles. Subsequently, we compute tectonic plate-pair spreading rates based on the tuned ages. The resultant alternative spreading-rate histories indicate that the CaCO3 tuned age model is most consistent with a conservative assumption of constant, or linearly changing, spreading rates. The CaCO3 tuned age model thus provides robust ages and durations for polarity chrons C6Bn.1n-C7n.1r, which are not based on astronomical tuning in the latest iteration of the geologic timescale. Furthermore, it provides independent evidence that the relatively large (several 10 000 years) time lags documented in the benthic foraminiferal isotope records relative to orbital eccentricity constitute a real feature of the Oligocene-Miocene climate system and carbon cycle. The age constraints from Site U1334 thus indicate that the delayed responses of the

Astronomy Against Terrorism: an Educational Astronomical Observatory Project in Peru

Science.gov (United States)

Ishitsuka, M.; Montes, H.; Kuroda, T.; Morimoto, M.; Ishitsuka, J.

2003-05-01

The Cosmos Coronagraphic Observatory was completely destroyed by terrorists in 1988. In 1995, in coordination with the Minister of Education of Peru, a project to construct a new Educational Astronomical Observatory has been executed. The main purpose of the observatory is to promote an interest in basic space sciences in young students from school to university levels, through basic astronomical studies and observations. The planned observatory will be able to lodge 25 visitors; furthermore an auditorium, a library and a computer room will be constructed to improve the interest of people in astronomy. Two 15-cm refractor telescopes, equipped with a CCD camera and a photometer, will be available for observations. Also a 6-m dome will house a 60-cm class reflector telescope, which will be donated soon, thanks to a fund collected and organized by the Nishi-Harima Astronomical Observatory in Japan. In addition a new modern planetarium donated by the Government of Japan will be installed in Lima, the capital of Peru. These installations will be widely open to serve the requirements of people interested in science.

Sports Stars: Analyzing the Performance of Astronomers at Visualization-based Discovery

Science.gov (United States)

Fluke, C. J.; Parrington, L.; Hegarty, S.; MacMahon, C.; Morgan, S.; Hassan, A. H.; Kilborn, V. A.

2017-05-01

In this data-rich era of astronomy, there is a growing reliance on automated techniques to discover new knowledge. The role of the astronomer may change from being a discoverer to being a confirmer. But what do astronomers actually look at when they distinguish between “sources” and “noise?” What are the differences between novice and expert astronomers when it comes to visual-based discovery? Can we identify elite talent or coach astronomers to maximize their potential for discovery? By looking to the field of sports performance analysis, we consider an established, domain-wide approach, where the expertise of the viewer (i.e., a member of the coaching team) plays a crucial role in identifying and determining the subtle features of gameplay that provide a winning advantage. As an initial case study, we investigate whether the SportsCode performance analysis software can be used to understand and document how an experienced Hi astronomer makes discoveries in spectral data cubes. We find that the process of timeline-based coding can be applied to spectral cube data by mapping spectral channels to frames within a movie. SportsCode provides a range of easy to use methods for annotation, including feature-based codes and labels, text annotations associated with codes, and image-based drawing. The outputs, including instance movies that are uniquely associated with coded events, provide the basis for a training program or team-based analysis that could be used in unison with discipline specific analysis software. In this coordinated approach to visualization and analysis, SportsCode can act as a visual notebook, recording the insight and decisions in partnership with established analysis methods. Alternatively, in situ annotation and coding of features would be a valuable addition to existing and future visualization and analysis packages.

Item Response Theory Models for Performance Decline during Testing

Science.gov (United States)

Jin, Kuan-Yu; Wang, Wen-Chung

2014-01-01

Sometimes, test-takers may not be able to attempt all items to the best of their ability (with full effort) due to personal factors (e.g., low motivation) or testing conditions (e.g., time limit), resulting in poor performances on certain items, especially those located toward the end of a test. Standard item response theory (IRT) models fail to…

Applications of generalizability theory and their relations to classical test theory and structural equation modeling.

Science.gov (United States)

Vispoel, Walter P; Morris, Carrie A; Kilinc, Murat

2018-03-01

Although widely recognized as a comprehensive framework for representing score reliability, generalizability theory (G-theory), despite its potential benefits, has been used sparingly in reporting of results for measures of individual differences. In this article, we highlight many valuable ways that G-theory can be used to quantify, evaluate, and improve psychometric properties of scores. Our illustrations encompass assessment of overall reliability, percentages of score variation accounted for by individual sources of measurement error, dependability of cut-scores for decision making, estimation of reliability and dependability for changes made to measurement procedures, disattenuation of validity coefficients for measurement error, and linkages of G-theory with classical test theory and structural equation modeling. We also identify computer packages for performing G-theory analyses, most of which can be obtained free of charge, and describe how they compare with regard to data input requirements, ease of use, complexity of designs supported, and output produced. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Parametrized tests of post-Newtonian theory using Advanced LIGO and Einstein Telescope

International Nuclear Information System (INIS)

Mishra, Chandra Kant; Arun, K. G.; Iyer, Bala R.; Sathyaprakash, B. S.

2010-01-01

General relativity has very specific predictions for the gravitational waveforms from inspiralling compact binaries obtained using the post-Newtonian (PN) approximation. We investigate the extent to which the measurement of the PN coefficients, possible with the second generation gravitational-wave detectors such as the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) and the third generation gravitational-wave detectors such as the Einstein Telescope (ET), could be used to test post-Newtonian theory and to put bounds on a subclass of parametrized-post-Einstein theories which differ from general relativity in a parametrized sense. We demonstrate this possibility by employing the best inspiralling waveform model for nonspinning compact binaries which is 3.5PN accurate in phase and 3PN in amplitude. Within the class of theories considered, Advanced LIGO can test the theory at 1.5PN and thus the leading tail term. Future observations of stellar mass black hole binaries by ET can test the consistency between the various PN coefficients in the gravitational-wave phasing over the mass range of 11-44M · . The choice of the lower frequency cutoff is important for testing post-Newtonian theory using the ET. The bias in the test arising from the assumption of nonspinning binaries is indicated.

Focus on astronomical predictable events

DEFF Research Database (Denmark)

Jacobsen, Aase Roland

2006-01-01

At the Steno Museum Planetarium we have for many occasions used a countdown clock to get focus om astronomical events. A countdown clock can provide actuality to predictable events, for example The Venus Transit, Opportunity landing on Mars and The Solar Eclipse. The movement of the clock attracs...... the public and makes a point of interest in a small exhibit area. A countdown clock can be simple, but it is possible to expand the concept to an eye-catching part of a museum....

The South African Astronomical Observatory

International Nuclear Information System (INIS)

1988-01-01

The geographical position, climate and equipment at the South African Astronomical Observatory (SAAO), together with the enthusiasm and efforts of SAAO scientific and technical staff and of visiting scientists, have enabled the Observatory to make a major contribution to the fields of astrophysics and cosmology. During 1987 the SAAO has been involved in studies of the following: supernovae; galaxies, including Seyfert galaxies; celestial x-ray sources; magellanic clouds; pulsating variables; galatic structure; binary star phenomena; nebulae; interstellar matter and stellar astrophysics

Towards a Theory for Testing Non-terminating Programs

DEFF Research Database (Denmark)

Gotlieb, Arnaud; Petit, Matthieu

2009-01-01

Non-terminating programs are programs that legally perform unbounded computations. Though they are ubiquitous in real-world applications, testing these programs requires new theoretic developments as usual definitions of test data adequacy criteria ignore infinite paths. This paper develops...... a theory of program-based structural testing based on operational semantics. Reasoning at the program semantics level permits to cope with infinite paths (and non-feasible paths) when defining test data adequacy criteria. As a result, our criteria respect the first Weyuker’s property on finite...... applicability, even for non-terminating programs. We discuss the consequences of this re-interpretation of test data adequacy criteria w.r.t. existing test coverage criteria....

The War's Positive Impact on the Canadian Astronomical Community

Science.gov (United States)

Broughton, Peter

2015-01-01

At the beginning of WWI, the Canadian astronomical community was tiny and astrophysical research was just beginning. By the end of the war, the country had established the forerunner of its National Research Council and had the world's largest fully operational telescope, thanks to the late entry of the USA into the conflict. By 1918, Canada was on the verge of making significant contributions to science.In spite of the immense loss of life in this pointless war, I am aware of only one casualty affecting Canadian professional astronomers, and that was the indirect death of James Chant, son of University of Toronto's only professor of astronomy. Other Canadian astronomers, including Tom Parker, Bert Topham, and Harry Plaskett were on active service; each of their stories is unique.Among those engaged in scientific work during the war were two Canadians temporarily in England: John McLennan whose helium research for dirigibles led him to establish a cryogenic lab in Toronto where the green line in the spectrum of the aurora was identified in 1925, and Allie Douglas who worked as a statistician in the War Office. Later work with Eddington led her to become his biographer and to her distinction as the first person in Canada to earn a PhD in astronomy (in 1926).

Statistical testing of the full-range leadership theory in nursing.

Science.gov (United States)

Kanste, Outi; Kääriäinen, Maria; Kyngäs, Helvi

2009-12-01

The aim of this study is to test statistically the structure of the full-range leadership theory in nursing. The data were gathered by postal questionnaires from nurses and nurse leaders working in healthcare organizations in Finland. A follow-up study was performed 1 year later. The sample consisted of 601 nurses and nurse leaders, and the follow-up study had 78 respondents. Theory was tested through structural equation modelling, standard regression analysis and two-way anova. Rewarding transformational leadership seems to promote and passive laissez-faire leadership to reduce willingness to exert extra effort, perceptions of leader effectiveness and satisfaction with the leader. Active management-by-exception seems to reduce willingness to exert extra effort and perception of leader effectiveness. Rewarding transformational leadership remained as a strong explanatory factor of all outcome variables measured 1 year later. The data supported the main structure of the full-range leadership theory, lending support to the universal nature of the theory.

Testing the Grandchildren's Received Affection Scale using Affection Exchange Theory.

Science.gov (United States)

Mansson, Daniel H

2013-04-01

The purpose of this study was to test the Grandchildren's Received Affection Scale (GRAS) using Affection Exchange Theory (Floyd, 2006). In accordance with Affection Exchange Theory, it was hypothesized that grandchildren's scores on the Trait Affection Received Scale (i.e., the extent to which individuals by nature receive affection) would be related significantly and positively to their reports of received affection from their grandparents (i.e., their scores on the GRAS). Additionally, a research question was asked to explore if grandchildren's received affection from their grandparents is dependent on their grandparent's biological sex or lineage (i.e., maternal vs paternal). Thus, young adult grandchildren (N = 422) completed the GRAS and the Trait Affection Received Scale. The results of zero-order Pearson correlational analyses provided support for the hypothesis, whereas the results of MANOVAs tests only partially support extant grandparent-grandchild theory and research. These findings broaden the scope of Affection Exchange Theory and also bolster the GRAS's utility in future grandparent-grandchild affectionate communication research.

Letters from Augustin Hallerstein, an eighteenth century Jesuit astronomer in Beijing

Science.gov (United States)

Juznic, Stanislav

2008-11-01

Augustin Hallerstein (1703-1774) was the last astronomer sent to Beijing by the Society of Jesus. He left Europe for China in his mid-thirties, and continued to send letters back home until he died thirty-five years later. These letters and reports contained important information on Chinese astronomy, and were read in the courts of Europe; many were also published. Hallerstein was one of the most important European astronomers in Beijing, his European publications surpassing those of his predecessors.

Quasi-periodic fractal patterns in geomagnetic reversals, geological activity, and astronomical events

International Nuclear Information System (INIS)

Puetz, Stephen J.; Borchardt, Glenn

2015-01-01

Highlights: • Spectral analysis indicates similar harmonics in astronomical and geological events. • Quasi-periodic cycles occur in tripling patterns of 30.44, 91.33, 274, 822, and 2466 myr. • Similar astro- and geo-phases suggest that the cycles develop from a common source. - Abstract: The cause of geomagnetic reversals remains a geological mystery. With the availability of improved paleomagnetic databases in the past three years, a reexamination of possible periodicity in the geomagnetic reversal rate seems warranted. Previous reports of cyclicity in the reversal rate, along with the recent discovery of harmonic cycles in a variety of natural events, sparked our interest in reevaluating possible patterns in the reversal rate. Here, we focus on geomagnetic periodicity, but also analyze paleointensity, zircon formation, star formation, quasar formation, supernova, and gamma ray burst records to determine if patterns that occur in other types of data have similar periodicity. If so, then the degree of synchronization will indicate likely causal relationships with geomagnetic reversals. To achieve that goal, newly available time-series records from these disciplines were tested for cyclicity by using spectral analysis and time-lagged cross-correlation techniques. The results showed evidence of period-tripled cycles of 30.44, 91.33, 274, 822, and 2466 million years, corresponding to the periodicity from a new Universal Cycle model. Based on the results, a fractal model of the universe is hypothesized in which sub-electron fractal matter acts as a dynamic medium for large-scale waves that cause the cycles in astronomical and geological processes. According to this hypothesis, the medium of sub-electron fractal matter periodically compresses and decompresses according to the standard laws for mechanical waves. Consequently, the compressions contribute to high-pressure environments and vice versa for the decompressions, which are hypothesized to cause the

Experimental test of the renormalizability consequences of the standard electroweak theory

International Nuclear Information System (INIS)

Bardin, D.Yu.

1984-01-01

The present status of the one-loop radiative corrections calculations in the standard electroweak theory is discussed. The possibilities of experimental tests of the higher order predictions of the standard theory is analysed in view of recent data, inclu-ing CERN p anti pcolcider data on Msub(W) and Msub(Z) measurement. The perspectives of these tests in the near future experiments are discussed

C++, objected-oriented programming, and astronomical data models

Science.gov (United States)

Farris, A.

1992-01-01

Contemporary astronomy is characterized by increasingly complex instruments and observational techniques, higher data collection rates, and large data archives, placing severe stress on software analysis systems. The object-oriented paradigm represents a significant new approach to software design and implementation that holds great promise for dealing with this increased complexity. The basic concepts of this approach will be characterized in contrast to more traditional procedure-oriented approaches. The fundamental features of objected-oriented programming will be discussed from a C++ programming language perspective, using examples familiar to astronomers. This discussion will focus on objects, classes and their relevance to the data type system; the principle of information hiding; and the use of inheritance to implement generalization/specialization relationships. Drawing on the object-oriented approach, features of a new database model to support astronomical data analysis will be presented.

A Test of Durkheim's Theory of Suicide in Primitive Societies.

Science.gov (United States)

Lester, David

1992-01-01

Classified primitive societies as high, moderate, or low on independent measures of social integration and social regulation to test Durkheim's theory of suicide. Estimated frequency of suicide did not differ between those societies predicted to have high, moderate, and low suicide rates. Durkheim's theory was not confirmed. (Author/NB)

Remote observatories for amateur astronomers using high-powered telescopes from home

CERN Document Server

Hubbell, Gerald R; Billard, Linda M

2015-01-01

Amateur astronomers who want to enhance their capabilities to contribute to science need look no farther than this guide to using remote observatories.  The contributors cover how to build your own remote observatory as well as the existing infrastructure of commercial networks of remote observatories that are available to the amateur. They provide specific advice on which programs to use based on your project objectives and offer practical project suggestions. Remotely controlled observatories have many advantages—the most obvious that the observer does not have to be physically present to carry out observations. Such an observatory can also be used more fully because its time can be scheduled and usefully shared among several astronomers working on different observing projects. More and more professional-level observatories are open to use by amateurs in this way via the Internet, and more advanced amateur astronomers can even build their own remote observatories for sharing among members of a society ...

Communicating the Science of Global Warming — the Role of Astronomers

Science.gov (United States)

Bennett, Jeffrey

2018-06-01

Global Warming is one of the most important and issues of our times, yet it is widely misunderstood among the general public (and politicians!). The American Astronomical Society has already joined many other scientific organizations in advocating for action on global warming (by supporting the AGU statement on global warming), but we as astronomers can do much more. The high public profile of astronomy gives us a unique platform — and credibility as scientists — for doing our part to educate the public about the underlying science of global warming. And while astronomers are not climate scientists, we use the same basic physics, and many aspects of global warming science come directly from astronomy, including the ways in which we measure the heat-absorbing potential of carbon dioxide and the hard evidence of greenhouse warming provided by studies of Venus. In this session, I will briefly introduce a few methods for communicating about global warming that I believe you will find effective in your own education efforts.

Astronomical Instruments in India

Science.gov (United States)

Sarma, Sreeramula Rajeswara

The earliest astronomical instruments used in India were the gnomon and the water clock. In the early seventh century, Brahmagupta described ten types of instruments, which were adopted by all subsequent writers with minor modifications. Contact with Islamic astronomy in the second millennium AD led to a radical change. Sanskrit texts began to lay emphasis on the importance of observational instruments. Exclusive texts on instruments were composed. Islamic instruments like the astrolabe were adopted and some new types of instruments were developed. Production and use of these traditional instruments continued, along with the cultivation of traditional astronomy, up to the end of the nineteenth century.

European astronomers' successes with the Hubble Space Telescope*

Science.gov (United States)

1997-02-01

[Figure: Laguna Nebula] Their work spans all aspects of astronomy, from the planets to the most distant galaxies and quasars, and the following examples are just a few European highlights from Hubble's second phase, 1994-96. A scarcity of midget stars Stars less massive and fainter than the Sun are much numerous in the Milky Way Galaxy than the big bright stars that catch the eye. Guido De Marchi and Francesco Paresce of the European Southern Observatory as Garching, Germany, have counted them. With the wide-field WFPC2 camera, they have taken sample censuses within six globular clusters, which are large gatherings of stars orbiting independently in the Galaxy. In every case they find that the commonest stars have an output of light that is only one-hundredth of the Sun's. They are ten times more numerous than stars like the Sun. More significant for theories of the Universe is a scarcity of very faint stars. Some astronomers have suggested that vast numbers of such stars could account for the mysterious dark matter, which makes stars and galaxies move about more rapidly than expected from the mass of visible matter. But that would require an ever-growing count of objects at low brightnesses, and De Marchi and Paresce find the opposite to be the case -- the numbers diminish. There may be a minimum size below which Nature finds starmaking difficult. The few examples of very small stars seen so far by astronomers may be, not the heralds of a multitude of dark-matter stars, but rareties. Unchanging habits in starmaking Confirmation that very small stars are scarce comes from Gerry Gilmore of the Institute of Astronomy in Cambridge (UK). He leads a European team that analyses long-exposure images in the WFPC2 camera, obtained as a by-product when another instrument is examining a selected object. The result is an almost random sample of well-observed stars and galaxies. The most remarkable general conclusion is that the make-up of stellar populations never seems to

A new theory of gravitation

International Nuclear Information System (INIS)

Logunov, A.A.

1989-01-01

The author believes that the General Relativity Theory (GRT) suffers from a substantial deficiency since it ignors the fundamental laws of conservation of energy. Einstein neglected the classical concept of the field due to his belief in the truth of the principle of equivalence between forces of inertid gravitation. This equivalence leads, as the author says, to nonequivalence of these forces, making GRT logically contradictory from the physical point of view. The author considers GRT as a certain stage in the course of the study of space-time and gravitation, and suggests a new theory called the Relativistic Theory of Gravitation (RTG) which obeys the fundamental laws of conservation, and which is justified in some of its aspects by astronomical observations. RTG does not suffer from some deficiencies met in Einsteins theory. One is nonunique predictions of gravitation effects within the boundaries of the solar system. Also, RTG refuses some hypothesis as that of black holes. 7 refs

Block iterative restoration of astronomical images with the massively parallel processor

International Nuclear Information System (INIS)

Heap, S.R.; Lindler, D.J.

1987-01-01

A method is described for algebraic image restoration capable of treating astronomical images. For a typical 500 x 500 image, direct algebraic restoration would require the solution of a 250,000 x 250,000 linear system. The block iterative approach is used to reduce the problem to solving 4900 121 x 121 linear systems. The algorithm was implemented on the Goddard Massively Parallel Processor, which can solve a 121 x 121 system in approximately 0.06 seconds. Examples are shown of the results for various astronomical images

Tests of the power PC theory of causal induction with negative contingencies.

Science.gov (United States)

Shanks, David R

2002-01-01

The power PC theory of causal induction (Cheng, 1997) proposes that causal estimates are based on the power p of a potential cause, where p is the contingency between the cause and effect normalized by the base rate of the effect. Previous tests of this theory have concentrated on generative causes that have positive contingencies with their associated outcomes. Here we empirically test this theory in two experiments using preventive causes that have negative contingencies for their outcomes. Contrary to the power PC theory, the results show that causal judgments vary with contingency across conditions of constant power p. This pattern is consistent, however, with several alternative accounts of causal judgment.

Generalisation of the test theory of special relativity to non-inertial frames

International Nuclear Information System (INIS)

Abolghasem, G.H.; Khajehpour, M.R.H.; Mansouri, R.

1989-01-01

We present a generalised test theory of special relativity, using a non-inertial frame. Within the framework of the special theory of relativity the transport and Einstein synchronisations are equivalent on a rigidly rotating disc. But in any theory with a preferred frame, such an equivalence does not hold. The time difference resulting from the two synchronisation procedures is a measurable quantity within the reach of existing clock systems on the Earth. The final result contains a term which depends on the angular velocity of the rotating system, and hence measures an absolute effect. This term is of crucial importance in our test theory of special relativity. (Author)

Test-particle motion in Einstein's unified field theory. III. Magnetic monopoles and charged particles

International Nuclear Information System (INIS)

Johnson, C.R.

1986-01-01

In a previous paper (paper I), we developed a method for finding the exact equations of structure and motion of multipole test particles in Einstein's unified field theory: the theory of the nonsymmetric field. In that paper we also applied the method and found in Einstein's unified field theory the equations of structure and motion of neutral pole-dipole test particles possessing no electromagnetic multipole moments. In a second paper (paper II), we applied the method and found in Einstein's unified field theory the exact equations of structure and motion of charged test particles possessing no magnetic monopole moments. In the present paper (paper III), we apply the method and find in Einstein's unified field theory the exact equations of structure and motion of charged test particles possessing magnetic monopole moments. It follows from the form of these equations of structure and motion that in general in Einstein's unified field theory a test particle possessing a magnetic monopole moment in a background electromagnetic field must also possess spin

AstroFrauenNetzwerk Survey Results - Career situation of female astronomers in Germany

Science.gov (United States)

Fohlmeister, J.; Helling, Ch.

2012-04-01

We survey the job situation of women in astronomy in Germany and of German women abroad and review indicators for their career development. Our sample includes women astronomers from all academic levels from doctoral students to professors, as well as female astronomers who have left the field. We find that networking and human support are among the most important factors for success. Experience shows that students should carefully choose their supervisor and collect practical knowledge abroad. We reflect the private situation of female German astronomers and find that prejudices are abundant, and are perceived as discriminating. We identify reasons why women are more likely than men to quit astronomy after they obtain their PhD degree. We give recommendations to young students on what to pay attention to in order to be on the successful path in astronomy.

The Selection and Protection of Optical Astronomical Observing Sites in China

Science.gov (United States)

Wenjing, Jin; Bai, Jinming; Yao, Yongqiang

2015-03-01

Before 1950 there are two observatories, Shanghai and Purple Mountain Astronomical Observatories (SHAO and PMO), and two observing stations, Qingdao and Kunming stations in China. With the requirements of astronomical research, two observatories, Beijing and Shaanxi Astronomical Observatories (BAO and SXAO) and two artificial satellite stations, Urumqi and Changchun, were established about 1960. Based on the current management, now there are 4 observatories, SHAO, PMO, NAOC(National Astronomical Observatories), which was grouped from BAO, YNAO and 2 others, as well as XAO (Xinjiang Astronomical Observatory). The optical 1-2 m class telescopes are being operated at former four observatories. SXAO is changed as National Time Service Center. Because of city expansion as well as the traveling and economic developments, these observatories are suffered severe light pollution. For example, Zo Ce is located at the suburb of Shanghai city. A 40 cm double astrograph was installed in 1900 and a 1.56 m optical reflector have been operated since November 1987. In 1994 the seeing is better than 1 and the night sky brightness in V is about 19 mag/arcsec 2, stars fainter than 20 mag with CCD are visibles. In 2007 a large playground was built in Zô Cè area. The light pollution is severe gradually. The night sky brightness has been increased to 15.8 mag/arcsec 2. The other observatories have similar situation. New site surveys and found new stations to solve the problem. Except the solar and radio stations of each Astronomical Observatory, now there are 3 optical observing sites at PMO (Hong-He, Xu-Yi and Yaoan), 2 at SHAO (Zô Cè and Tian Huang Ping) and 2 at YNAO (Kunming and Gao-Mei-Gu) as well as 1 optical observing site at BAO (Xing-Long). The best observing site is Gao-Mei-Gu, which is selected as the optical observing site of YNAO and where atmospheric turbulence distribution is 0.11 near ground with heights from 6.5m to 2.7m during night. Sky brightness in B and V band

BOOK REVIEW: The Wandering Astronomer

Science.gov (United States)

Swinbank, Elizabeth

2000-09-01

Fans of Patrick Moore will like this book. I enjoyed it more than I expected, having anticipated a collection of personal anecdotes of the type favoured by certain tedious after-dinner speakers. Some of the 41 short items it contains do tend towards that category, but there are also some nuggets which might enliven your physics teaching. For example, did you know that, in a murder trial in 1787, the defendant's belief that the Sun was inhabited was cited as evidence of his insanity? This was despite his views being shared by many astronomers of the day including William Herschel. Or that Clyde Tombaugh had a cat called Pluto after the planet he discovered, which was itself named by an eleven-year-old girl? Another gem concerns a brief flurry, in the early 1990s, over a suspected planet orbiting a pulsar; variations in the arrival time of its radio pulses indicated the presence of an orbiting body. These shifts were later found to arise from an error in a computer program that corrected for the Earth's motion. The programmer had assumed a circular orbit for the Earth whereas it is actually elliptical. The book is clearly intended for amateur astronomers and followers of Patrick Moore's TV programmes. There is plenty of astronomy, with an emphasis on the solar system, but very little astrophysics. The author's metricophobia means that quantities are given in imperial units throughout, with metric equivalents added in brackets (by an editor, I suspect) which can get irritating, particularly as powers-of-ten notation is avoided. It is quite a novelty to see the temperature for hydrogen fusion quoted as 18 000 000 °F (10 000 000 °C). By way of contrast, astronomical terms are used freely - ecliptic, first-magnitude star, and so on. Such terms are defined in a glossary at the end, but attention is not drawn to this and I only stumbled across it by chance. Patrick Moore obviously knows his public, and this book will serve them well. For physics teachers and students

A Virtual Astronomical Research Machine in No Time (VARMiNT)

Science.gov (United States)

Beaver, John

2012-05-01

We present early results of using virtual machine software to help make astronomical research computing accessible to a wider range of individuals. Our Virtual Astronomical Research Machine in No Time (VARMiNT) is an Ubuntu Linux virtual machine with free, open-source software already installed and configured (and in many cases documented). The purpose of VARMiNT is to provide a ready-to-go astronomical research computing environment that can be freely shared between researchers, or between amateur and professional, teacher and student, etc., and to circumvent the often-difficult task of configuring a suitable computing environment from scratch. Thus we hope that VARMiNT will make it easier for individuals to engage in research computing even if they have no ready access to the facilities of a research institution. We describe our current version of VARMiNT and some of the ways it is being used at the University of Wisconsin - Fox Valley, a two-year teaching campus of the University of Wisconsin System, as a means to enhance student independent study research projects and to facilitate collaborations with researchers at other locations. We also outline some future plans and prospects.

Harvey Butcher: a passion for astronomical instrumentation

Science.gov (United States)

Bhathal, Ragbir

2014-11-01

This paper covers some aspects of the scientific life of Harvey Butcher who was the Director of the Research School for Astronomy and Astrophysics at the Australian National University in Canberra from September 2007 to January 2013. He has made significant contributions to research on the evolution of galaxies, nucleosynthesis, and on the design and implementation of advanced astronomical instrumentation including LOFAR (Low Frequency Array Radio telescope). He is well known for his discovery of the Butcher-Oemler effect. Before coming to Australia he was the Director of the Netherlands Foundation for Research in Astronomy from September 1991 to January 2007. In 2005 he was awarded a Knighthood in the Order of the Netherlands Lion for contributions to interdisciplinary science, innovation and public outreach.This paper is based on an interview conducted by the author with Harvey Butcher for the National Project on Significant Australian Astronomers sponsored by the National Library of Australia. Except otherwise stated, all quotations used in this paper are from the Butcher interview which has been deposited in the Oral History Archives of the National Library.

Sketching the moon an astronomical artist's guide

CERN Document Server

Handy, Richard; McCague, Thomas; Rix, Erika; Russell, Sally

2012-01-01

Soon after you begin studying the sky through your small telescope or binoculars, you will probably be encouraged by others to make sketches of what you see. Sketching is a time-honored tradition in amateur astronomy and dates back to the earliest times, when telescopes were invented. Even though we have lots of new imaging technologies nowadays, including astrophotography, most observers still use sketching to keep a record of what they see, make them better observers, and in hopes of perhaps contributing something to the body of scientific knowledge about the Moon. Some even sketch because it satisfies their artistic side. The Moon presents some unique challenges to the astronomer-artist, the Moon being so fond of tricks of the light. Sketching the Moon: An Astronomical Artist’s Guide, by five of the best lunar observer-artists working today, will guide you along your way and help you to achieve really high-quality sketches. All the major types of lunar features are covered, with a variety of sketching te...

Suppression of Astronomical Sources Using Starshades and the McMath-Pierce Solar Telescope

Science.gov (United States)

Novicki, Megan; Warwick, Steve; Smith, Daniel; Richards, Michael; Harness, Anthony

2016-01-01

The external starshade is a method for the direct detection and spectral characterization of terrestrial planets around other stars, a key goal identified in ASTRO2010. Tests of this approach have been and continue to be conducted in the lab and in the field (Samuele et al., 2010, Glassman et al., 2014) using non-collimated light sources with a spherical wavefront. We extend the current approach to performing night-time observations of astronomical objects using small-scale (approximately 1/300th) starshades and the McMath-Pierce Solar Telescope at Kitt Peak National Observatory. We placed a starshade directly in the path of the beam from an astronomical object in front of the main heliostat. Using only flat mirrors, we then directed the light through the observatory path and reflected it off the West heliostat to an external telescope located approximately 270m away, for an effective baseline of 420m.This configuration allowed us to make measurements of flat wavefront sources with a Fresnel number close to those expected in proposed full-scale space configurations. We present the results of our engineering runs conducted in 2015.

SAADA: Astronomical Databases Made Easier

Science.gov (United States)

Michel, L.; Nguyen, H. N.; Motch, C.

2005-12-01

Many astronomers wish to share datasets with their community but have not enough manpower to develop databases having the functionalities required for high-level scientific applications. The SAADA project aims at automatizing the creation and deployment process of such databases. A generic but scientifically relevant data model has been designed which allows one to build databases by providing only a limited number of product mapping rules. Databases created by SAADA rely on a relational database supporting JDBC and covered by a Java layer including a lot of generated code. Such databases can simultaneously host spectra, images, source lists and plots. Data are grouped in user defined collections whose content can be seen as one unique set per data type even if their formats differ. Datasets can be correlated one with each other using qualified links. These links help, for example, to handle the nature of a cross-identification (e.g., a distance or a likelihood) or to describe their scientific content (e.g., by associating a spectrum to a catalog entry). The SAADA query engine is based on a language well suited to the data model which can handle constraints on linked data, in addition to classical astronomical queries. These constraints can be applied on the linked objects (number, class and attributes) and/or on the link qualifier values. Databases created by SAADA are accessed through a rich WEB interface or a Java API. We are currently developing an inter-operability module implanting VO protocols.

Investigating Student Understanding of the Universe: Perceptions of Astronomical Sizes and Distances

Science.gov (United States)

Camarillo, Carmelita; Coble, K.; Hayes, V.; Nickerson, M.; Cochran, G. L.; Bailey, J. M.; McLin, K. M.; Cominsky, L. R.

2011-05-01

Student perceptions regarding astronomical sizes and distances are being analyzed for Chicago State University's Basic Astronomy course. This area is of great interest to further understand the students’ learning processes and to produce more effective instruction. Insights from cognitive psychology have shown that perceptions are related to prior experiences and current knowledge. Students enter into this course with different mental representations, and these representations can affect their learning. Through a repeated measures design, perceptions are analyzed through several instruments. The instruments implemented are pre-tests surveys (before lab), exams (after lab), lab comments, and interviews. Preliminary analysis reveals that students who have difficulty with astronomical sizes and distances have been more strongly influenced by culture and the media whereas those who had less difficulty expanded on their personal prior experiences. This project is part of a larger study; also see our posters on the structure of the universe, dark matter, the age and expansion of the universe. This work was supported by NASA ROSES E/PO Grant #NNXlOAC89G, as well as by the Illinois Space Grant Consortium and National Science Foundation CCLI Grant #0632563 at Chicago State University and the Fermi E/PO program at Sonoma State University.

Procesos para una Astronomía que le aporte a Colombia

OpenAIRE

Duque Escobar, Gonzalo

2011-01-01

Se ha validado el Plan Nacional de Desarrollo Tecnológico en Astronomía 2011-2030, para el Plan Estratégico 2009-2012 de la Comisión Colombiana del Espacio CCE, por el Grupo de Astronáutica, Astronomía y Medicina Aeroespacial. Esperamos que el grupo de astrónomos convocado, responsable de la investigación centrado en procesos científicos existentes y no en distractores, pueda señalar las acciones pertinentes e identificar los recursos necesarios, para hacer viable un desarrollo científico y t...

Methodological issues in testing the marginal productivity theory

NARCIS (Netherlands)

P.T. Gottschalk (Peter); J. Tinbergen (Jan)

1982-01-01

textabstractPrevious tests of the marginal productivity theory have been criticized on several grounds reviewed by the authors. One important deficiency has been the small number of factor inputs entered in the production functions. In 1978 Gottschalk suggested a method to estimate production

IYL Blog: Astronomers travel in time and space with light

Science.gov (United States)

Mather, John C.

2015-01-01

As an astronomer, I use light to travel through the universe, and to look back in time to when the universe was young. So do you! All of us see things as they were when the light was emitted, not as they are now. The farthest thing you can easily see without a telescope is the Andromeda Nebula, which is a galaxy like the Milky Way, about 2.5 million light years away. You see it as it was 2.5 million years ago, and we really don't know what it looks like today; the disk will have rotated a bit, new stars will have been born, there could have been all kinds of exploding stars, and the black hole in the middle could be lighting up. People may be skeptical of the Big Bang theory, even though we have a TV show named for it, but we (I should say Penzias and Wilson) measured its heat radiation 51 years ago at Bell Telephone Labs in New Jersey. Their discovery marks the beginning of the era of cosmology as a measurement science rather than speculation. Penzias and Wilson received the Nobel Prize in 1978 for their finding, which had been predicted in 1948 by Alpher and Herman. By the way, heat radiation is just another form of light - we call it radiation because we can't see it, but it's exactly the same phenomenon of electromagnetic waves, and the only difference is the wavelength. In the old days of analog television, if you tuned your TV in between channels, about 1% of the snow that you could see came from the Big Bang. So when we look at the heat radiation of the early universe, we really are gazing right at what seems to us a cosmic fireball, which surrounds us completely. It's a bit of an illusion; if you can imagine what astronomers in other galaxies would see, they would also feel surrounded by the fireball, and they would also think they were in the middle. So from a mathematical version of imagination, we conclude that there is no observable center and no edge of our universe, and that the heat of the fireball fills the entire universe uniformly. Astronomers are

La astronomía: ciencia olvidada en la escuela, ¿cómo recuperarla?

OpenAIRE

Aranzazu Zea, Daniel Alejandro

2013-01-01

Resumen: Esta propuesta tiene la intención de diseñar una cartilla para la enseñanza de la astronomía en la básica primaria, principalmente en el Colegio Santo Domingo de Guzmán, ubicado en el sector de Zamora, Bello. Se inicia la propuesta debido a que en el Colegio la astronomía no es un tema de mucha importancia en la enseñanza y es muy poca la transversalización con las diferentes áreas de la institución. La astronomía es vista como algo aparte de todas las asignaturas, sin saber la gran ...

Radio Recombination Lines Their Physics and Astronomical Applications

CERN Document Server

Gordon, MA

2008-01-01

Includes the history of RRL detections, the astrophysics underlying their intensities and line shapes including topics like departures from LTE and Stark broadening, the maximum possible size of an atom, and descriptions of the astronomical topics for which RRLs have proved to be effective tools.

Radio astronomical interferometry and x-ray's computerized tomography

Energy Technology Data Exchange (ETDEWEB)

Rodriguez, L F [Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Astronomia

1982-01-01

Radio astronomical interferometry and computerized tomography are techniques of great importance for astronomy and medicine, respectively. In this paper we emphasize that both techniques are based on the same mathematical principles, and present them as an example of interaction between basic and applied science.

Undergraduates' intentions to take a second language proficiency test: a comparison of predictions from the theory of planned behavior and social cognitive theory.

Science.gov (United States)

Lin, Bih-Jiau; Chiou, Wen-Bin

2010-06-01

English competency has become essential for obtaining a better job or succeeding in higher education in Taiwan. Thus, passing the General English Proficiency Test is important for college students in Taiwan. The current study applied Ajzen's theory of planned behavior and the notions of outcome expectancy and self-efficacy from Bandura's social cognitive theory to investigate college students' intentions to take the General English Proficiency Test. The formal sample consisted of 425 undergraduates (217 women, 208 men; M age = 19.5 yr., SD = 1.3). The theory of planned behavior showed greater predictive ability (R2 = 33%) of intention than the social cognitive theory (R2 = 7%) in regression analysis and made a unique contribution to prediction of actual test-taking behavior one year later in logistic regression. Within-model analyses indicated that subjective norm in theory of planned behavior and outcome expectancy in social cognitive theory are crucial factors in predicting intention. Implications for enhancing undergraduates' intentions to take the English proficiency test are discussed.

Metal-Containing Molecules Beyond the Solar System: a Laboratory and Radio Astronomical Perspective

Science.gov (United States)

Ziurys, L. M.

2010-06-01

Although the history of interstellar molecules began around 1970, with the millimeter-wave detection of CO in the Orion Nebula, metal-containing species have been somewhat elusive for astronomical searches. Only in the past two decades have metal-bearing molecules been identified in space, starting with metal halides (NaCl, KCl, AlCl, and AlF), and then metal cyanide and isocyanide species (MgNC, MgCN, NaCN, and AlNC). Moreover, the metal-containing molecules seemed to be present in a single astronomical object: the envelope of a dying, carbon-rich star, IRC+10216. However, with improvements both in laboratory spectroscopy and telescope sensitivity, it is becoming clear that the relevance of metal-containing species in astrophysics is increasing. Metal oxide and hydroxide species, such as AlO and AlOH, have recently been identified in interstellar space. Metal-containing molecules are now being found in other astronomical sources, such as the oxygen-rich shell surrounding VY Canis Majoris, a supergiant star. These new astronomical discoveries will be presented, as well as the laboratory measurements that made them possible. New directions in rotational spectroscopy of metal-bearing molecules will also be discussed.

ISO Results Presented at International Astronomical Union

Science.gov (United States)

1997-08-01

. Astronomers can now combine ISO's results with observations of the same object and others like it, at sub-millimetre radio wavelengths, to build up a detailed picture of the earliest stages of star formation. Ward-Thompson says: "Our fellow-astronomers thought we had no chance of detecting pre-stellar cores with any instruments available today. Now that we've done it, with the radio telescopes on the ground and with ISO in space, a new chapter in the study of star formation can begin. Already our results contradict the theory that a pre-stellar core should spin rapidly. It doesn't. In addition, our observations have shown us that the manner in which a newly-forming star first collapses is different from that which was previously predicted." Looking for the origin of planets Our immediate cosmic mother was the Solar Nebula, the cloud of gas and dust that supposedly swirled around the Sun at its birth about 4.5 billion years ago. Gravity flattened the gas and dust into a disk, like a giant version of the rings of Saturn. Stony and icy grains of dust congealed to make the Sun's family of planets, including the Earth. The comets are relics of the construction of the Solar System, and ISO has investigated their chemical composition. Yet the concept of planet-making in the dusty disk of the Solar Nebula was just a theory until the advent of infrared space astronomy. One of the more time-intensive programmes of ISO deals with the existence of disks of dust particles around normal stars. The Sun still has a disk, visible as the Zodiacal Light seen close to the horizon after sunset in spring or before sunrise in autumn. The dust is, however, too sparse to be detected, if one were looking for a similar feature in the surroundings of another star. Therefore it came as a big surprise when ISO's predecessor, the Dutch-US-UK Infrared Astronomical Satellite (1983), detected similar dust disks around a few nearby stars, notably Vega and Beta Pictoris, with much more material than the Sun

Astronomical tunings of the Oligocene-Miocene transition from Pacific Ocean Site U1334 and implications for the carbon cycle

NARCIS (Netherlands)

Beddow, Helen M.; Liebrand, Diederik; Wilson, Douglas S.; Hilgen, Frits J.; Sluijs, Appy; Wade, Bridget S.; Lourens, Lucas J.

2018-01-01

Astronomical tuning of sediment sequences requires both unambiguous cycle pattern recognition in climate proxy records and astronomical solutions, as well as independent information about the phase relationship between these two. Here we present two different astronomically tuned age models for the

Support for the Astronomically Calibrated 40Ar/39Ar Age of Fish Canyon Sanidine

DEFF Research Database (Denmark)

Rivera, Tiffany; Storey, Michael; Zeeden, Christian

2011-01-01

al. (2008) determined an astronomically calibrated 40Ar/39Ar age of 28.201 0.046 Ma (2), relative to the indirect astronomically tuned Moroccan Melilla Basin Messâdit section. Here, we provide independent verification for the Kuiper, et al. (2008) FCs age using sanidines extracted from the A1 tephra...

Alexander the Great's Tomb at Siwa: The Astronomical Orientation

Science.gov (United States)

Papathanassiou, M.; Souvaltzis, Em.; Souvaltzi, L.; Moussas, X.

A preliminary report on the possible astronomical orientation of the Tomb of Alexander the Great, recently found and excavated by the greek archaeologist Liana Souvaltzi. The tomb is a greek building of doric style. Its enormous dimensions make it the largest amongst the found macedonian tombs (much bigger than the tomb of Philip II, Alexander's father). The tomb faces generally south---west and its orientation could be related either to the constellation of Centaurus or to the star Canopus. The walls of the two long sides of the building have strickingly different widhts. Moreover each wall has three doors (opposite in pairs) of slightly different sizes. We examine the possibility the openings of the doors and their assymetries to be designed and constructed according to some astronomical (solar or stellar) orientations.

Viewing and imaging the solar system a guide for amateur astronomers

CERN Document Server

Clark, Jane

2015-01-01

Viewing and Imaging the Solar System: A Guide for Amateur Astronomers is for those who want to develop their ability to observe and image Solar System objects, including the planets and moons, the Sun, and comets and asteroids. They might be beginners, or they may have already owned and used an astronomical telescope for a year or more. Newcomers are almost always wowed by sights such as the rings of Saturn and the moons of Jupiter, but have little idea how to find these objects for themselves (with the obvious exceptions of the Sun and Moon). They also need guidance about what equipment to use, besides a telescope. This book is written by an expert on the Solar System, who has had a lot of experience with outreach programs, which teach others how to make the most of relatively simple and low-cost equipment. That does not mean that this book is not for serious amateurs. On the contrary, it is designed to show amateur astronomers, in a relatively light-hearted—and math-free way—how to become serious.

Testing quantity theory of money for the Turkish economy

OpenAIRE

Levent, Korap

2007-01-01

In this paper, it is tried to test the main assumptions of the Quantity Theory of Money for the Turkish economy. Using some contemporaneous estimation techniques to examine the long-run stationary economic relationships on which the quantity theory is constructed, it is found that stationary characteristics of the velocitities of narrowly and broadly defined monetary aggregates cannot be rejected. However, monetary aggregates seem to be endogenous for the long-run evoluation of prices and rea...

Astronomers Make First Images With Space Radio Telescope

Science.gov (United States)

1997-07-01

part of the VLBA instrument, was modified over the past four years to allow it to incorporate data from the satellite. Correlation of the observational data was completed successfully on June 12, after the exact timing of the satellite recording was established. Further computer processing produced an image of PKS 1519-273 -- the first image ever produced using a radio telescope in space. For Jim Ulvestad, the NRAO astronomer who made the first image, the success ended a long quest for this new capability. Ulvestad was involved in an experiment more than a decade ago in which a NASA communications satellite, TDRSS, was used to test the idea of doing radio astronomical imaging by combining data from space and ground radio telescopes. That experiment showed that an orbiting antenna could, in fact, work in conjunction with ground-based radio observatories, and paved the way for HALCA and a planned Russian radio astronomy satellite called RadioAstron. "This first image is an important technical milestone, and demonstrates the feasibility of a much more advanced mission, ARISE, currently being considered by NASA," Ulvestad said. The first image showed no structure in the object, even at the extremely fine level of detail achievable with HALCA; it is what astronomers call a "point source." This object also appears as a point source in all-ground-based observations. In addition, the 1986 TDRSS experiment observed the object, and, while this experiment did not produce an image, it indicated that PKS 1519-273 should be a point source. "This simple point image may not appear very impressive, but its beauty to us is that it shows our entire, complex system is functioning correctly. The system includes not only the orbiting and ground-based antennas, but also the orbit determination, tracking stations, the correlator, and the image-processing software," said Jonathan Romney, the NRAO astronomer who led the development of the VLBA correlator, and its enhancement to process data

A Mythological, Philosophical and Astronomical approach of our solar system

Science.gov (United States)

Drivas, Sotirios; Kastanidou, Sofia

2016-04-01

Teaching Geography in the first Class of Gymnasium - secondary education we will focus in Solar System: Astronomical approach: Students will look and find the astronomical data of the planets, they will make comparisons between the sizes of their radius, they will find the distance from the Sun, they will search the relative motion, they will calculate the gravity on each planet, etc. Mythological approach: We will search the names and meanings of the planets based on Greek mythological origin. Philosophical approach: Regarding the philosophical approach of the "solar system" we will look and find: • Why planets are called so? • How did planets get their names? • What are the periods of Greek astronomy? • What were the astronomical instruments of ancient Greeks and who did built them? • What were the Greek philosophers and astronomers? When did they live and what did they discover? • Which method did Eratosthenes of Cyrene apply about 206B.C. to serve a real measurement of the earth's radius? • What was the relationship between science and religion in ancient Greece? Literature approach: At the end of the program students will write their opinion in subject "Having a friend from another planet" based on the book of Antoine de Saint - Exupéry "The little prince". Law approach: A jurist working in Secondary Education will visits our school and engages students in the Space Law. Artistic approach: Students will create their own posters of our planetary system. The best posters will be posted on the school bulletin board to display their work. Visit: Students and teachers will visit the Observatory of Larissa where they will see how observatory works and talk with scientists about their job. They will look through telescopes and observe the sun.

Astronomical Polarimetry with the RIT Polarization Imaging Camera

Science.gov (United States)

Vorobiev, Dmitry V.; Ninkov, Zoran; Brock, Neal

2018-06-01

In the last decade, imaging polarimeters based on micropolarizer arrays have been developed for use in terrestrial remote sensing and metrology applications. Micropolarizer-based sensors are dramatically smaller and more mechanically robust than other polarimeters with similar spectral response and snapshot capability. To determine the suitability of these new polarimeters for astronomical applications, we developed the RIT Polarization Imaging Camera to investigate the performance of these devices, with a special attention to the low signal-to-noise regime. We characterized the device performance in the lab, by determining the relative throughput, efficiency, and orientation of every pixel, as a function of wavelength. Using the resulting pixel response model, we developed demodulation procedures for aperture photometry and imaging polarimetry observing modes. We found that, using the current calibration, RITPIC is capable of detecting polarization signals as small as ∼0.3%. The relative ease of data collection, calibration, and analysis provided by these sensors suggest than they may become an important tool for a number of astronomical targets.

156th Symposium of the International Astronomical Union

CERN Document Server

Kołaczek, Barbara

1993-01-01

In this review talk, I would like to report on the proper motion analysis, which has been recently carried out together with M. Soma and M. Yoshizawa: There has been a persistent demand in astronomy for accurate stellar positions and proper motions, which are represented by an inertial reference system constructed on the basis of a set of consistent astronomical constants. In the reference system the precessional constant plays a primary role. In a series of papers Fricke (1967a,b, 1977a,b) has deter­ mined the luni-solar precessional correction to Newcomb's value and the fictitious motion of the equinox, which have been adopted in the "IAU (1976) System of Astronomical Con­ stants". Based on the precessional correction and the equinoctial motion thus established, the fundamental reference system, the FK5 system (Fricke et al. 1988) for positions and proper motions, has been constructed. However, for several years geodetic VLBI (McCarthy & Luzum 1991) and LLR (Williams et at. 1991) observations have bee...

Celestial delights the best astronomical events through 2020

CERN Document Server

Reddy, Francis

2012-01-01

Celestial Delights is the essential 'TV Guide' for the sky. Through extensive graphics integrated with an eight-year-long calendar of sky events, it provides a look at "don't miss" sky events, mostly for naked-eye and binocular observing. It is organized by ease of observation – lunar phases and the brighter planets come first, with solar eclipses, the aurora, and comets coming later. This third edition also includes a hefty dose of sky lore, astronomical history, and clear overviews of current science. It provides a handy reference to upcoming naked-eye events, with information broken out in clear and simple diagrams and tables that are cross-referenced against a detailed almanac for each year covered. This book puts a variety of information all in one place, presents it in a friendly way that does not require prior in-depth astronomical knowledge, and provides the context and historical background for understanding events that astronomy software or web sites lack.

Visualization of Multi-mission Astronomical Data with ESASky

Science.gov (United States)

Baines, Deborah; Giordano, Fabrizio; Racero, Elena; Salgado, Jesús; López Martí, Belén; Merín, Bruno; Sarmiento, María-Henar; Gutiérrez, Raúl; Ortiz de Landaluce, Iñaki; León, Ignacio; de Teodoro, Pilar; González, Juan; Nieto, Sara; Segovia, Juan Carlos; Pollock, Andy; Rosa, Michael; Arviset, Christophe; Lennon, Daniel; O'Mullane, William; de Marchi, Guido

2017-02-01

ESASky is a science-driven discovery portal to explore the multi-wavelength sky and visualize and access multiple astronomical archive holdings. The tool is a web application that requires no prior knowledge of any of the missions involved and gives users world-wide simplified access to the highest-level science data products from multiple astronomical space-based astronomy missions plus a number of ESA source catalogs. The first public release of ESASky features interfaces for the visualization of the sky in multiple wavelengths, the visualization of query results summaries, and the visualization of observations and catalog sources for single and multiple targets. This paper describes these features within ESASky, developed to address use cases from the scientific community. The decisions regarding the visualization of large amounts of data and the technologies used were made to maximize the responsiveness of the application and to keep the tool as useful and intuitive as possible.

Two Tests of Maslow's Theory of Need Fulfillment.

Science.gov (United States)

Betz, Ellen L.

1984-01-01

Conducted a two-part test of Maslow's theory of human motivation and explored the relationships between need deficiencies and (1) need importance and (2) life satisfaction in female college graduates (N=474). Results support Maslow's model regarding need deficiencies and their relationship to life satisfaction. (LLL)

Terahertz Mixing Characteristics of NbN Superconducting Tunnel Junctions and Related Astronomical Observations

Science.gov (United States)

Li, J.

2010-01-01

High-sensitivity superconducting SIS (superconductor-insulator-superconductor) mixers are playing an increasingly important role in the terahertz (THz) astronomical observation, which is an emerging research frontier in modern astrophysics. Superconducting SIS mixers with niobium (Nb) tunnel junctions have reached a sensitivity close to the quantum limit, but have a frequency limit about 0.7 THz (i.e., gap frequency of Nb tunnel junctions). Beyond this frequency Nb superconducting films will absorb energetic photons (i.e., energy loss) to break Cooper pairs, thereby resulting in significant degradation of the mixer performance. Therefore, it is of particular interest to develop THz superconducting SIS mixers incorporating tunnel junctions with a larger energy gap. Niobium-nitride (NbN) superconducting tunnel junctions have been long known for their large energy gap, almost double that of Nb ones. With the introduction of epitaxially grown NbN films, the fabrication technology of NbN superconducting tunnel junctions has been considerably improved in the recent years. Nevertheless, their performances are still not as good as Nb ones, and furthermore they are not yet demonstrated in real astronomical applications. Given the facts mentioned above, in this paper we systematically study the quantum mixing behaviors of NbN superconducting tunnel junctions in the THz regime and demonstrate an astronomical testing observation with a 0.5 THz superconducting SIS mixer developed with NbN tunnel junctions. The main results of this study include: (1) successful design and fabrication of a 0.4˜0.6 THz waveguide mixing circuit with the high-dielectric-constant MgO substrate; (2) successful fabrication of NbN superconducting tunnel junctions with the gap voltage reaching 5.6 mV and the quality factor as high as 15; (3) demonstration of a 0.5 THz waveguide NbN superconducting SIS mixer with a measured receiver noise temperature (no correction) as low as five times the quantum limit

Tribute to an Astronomer: The Work of Max Ernst on Wilhelm Tempel

Science.gov (United States)

Nazé, Yaël

2016-05-01

In 1964-1974, the German artist Max Ernst created, with the help of two friends, a series of works (books, movie, and paintings) related to the astronomer Wilhelm Tempel. Mixing actual texts by Tempel and artistic features, this series pays homage to the astronomer by recalling his life and discoveries. Moreover, the core of the project, the book Maximiliana or the Illegal Practice of Astronomy, actually depicts the way science works, making this work of art a most original tribute to a scientist.

Using Modern Technologies to Capture and Share Indigenous Astronomical Knowledge

Science.gov (United States)

Nakata, Martin; Hamacher, Duane W.; Warren, John; Byrne, Alex; Pagnucco, Maurice; Harley, Ross; Venugopal, Srikumar; Thorpe, Kirsten; Neville, Richard; Bolt, Reuben

2014-06-01

Indigenous Knowledge is important for Indigenous communities across the globe and for the advancement of our general scientific knowledge. In particular, Indigenous astronomical knowledge integrates many aspects of Indigenous Knowledge, including seasonal calendars, navigation, food economics, law, ceremony, and social structure. Capturing, managing, and disseminating this knowledge in the digital environment poses a number of challenges, which we aim to address using a collaborative project emerging between experts in the higher education, library, archive and industry sectors. Using Microsoft's WorldWide Telescope and Rich Interactive Narratives technologies, we propose to develop software, media design, and archival management solutions to allow Indigenous communities to share their astronomical knowledge with the world on their terms and in a culturally sensitive manner.

The director task: A test of Theory-of-Mind use or selective attention?

Science.gov (United States)

Rubio-Fernández, Paula

2017-08-01

Over two decades, the director task has increasingly been employed as a test of the use of Theory of Mind in communication, first in psycholinguistics and more recently in social cognition research. A new version of this task was designed to test two independent hypotheses. First, optimal performance in the director task, as established by the standard metrics of interference, is possible by using selective attention alone, and not necessarily Theory of Mind. Second, pragmatic measures of Theory-of-Mind use can reveal that people actively represent the director's mental states, contrary to recent claims that they only use domain-general cognitive processes to perform this task. The results of this study support both hypotheses and provide a new interactive paradigm to reliably test Theory-of-Mind use in referential communication.

Available Tools and Challenges Classifying Cutting-Edge and Historical Astronomical Documents

Science.gov (United States)

Lagerstrom, Jill

2015-08-01

The STScI Library assists the Science Policies Division in evaluating and choosing scientific keywords and categories for proposals for the Hubble Space Telescope mission and the upcoming James Webb Space Telescope mission. In addition we are often faced with the question “what is the shape of the astronomical literature?” However, subject classification in astronomy in recent times has not been cultivated. This talk will address the available tools and challenges of classifying cutting-edge as well as historical astronomical documents. In at the process, we will give an overview of current and upcoming practices of subject classification in astronomy.

AstroWeb -- Internet Resources for Astronomers

Science.gov (United States)

Jackson, R. E.; Adorf, H.-M.; Egret, D.; Heck, A.; Koekemoer, A.; Murtagh, F.; Wells, D. C.

AstroWeb is a World Wide Web (WWW) interface to a collection of Internet accessible resources aimed at the astronomical community. The collection currently contains more than 1000 WWW, Gopher, Wide Area Information System (WAIS), Telnet, and Anonymous FTP resources, and it is still growing. AstroWeb provides the additional value-added services: categorization of each resource; descriptive paragraphs for some resources; searchable index of all resource information; 3 times daily search for ``dead'' or ``unreliable'' resources.

Extracting meaning from astronomical telegrams

Science.gov (United States)

Graham, Matthew; Conwill, L.; Djorgovski, S. G.; Mahabal, A.; Donalek, C.; Drake, A.

2011-01-01

The rapidly emerging field of time domain astronomy is one of the most exciting and vibrant new research frontiers, ranging in scientific scope from studies of the Solar System to extreme relativistic astrophysics and cosmology. It is being enabled by a new generation of large synoptic digital sky surveys - LSST, PanStarrs, CRTS - that cover large areas of sky repeatedly, looking for transient objects and phenomena. One of the biggest challenges facing these is the automated classification of transient events, a process that needs machine-processible astronomical knowledge. Semantic technologies enable the formal representation of concepts and relations within a particular domain. ATELs (http://www.astronomerstelegram.org) are a commonly-used means for reporting and commenting upon new astronomical observations of transient sources (supernovae, stellar outbursts, blazar flares, etc). However, they are loose and unstructured and employ scientific natural language for description: this makes automated processing of them - a necessity within the next decade with petascale data rates - a challenge. Nevertheless they represent a potentially rich corpus of information that could lead to new and valuable insights into transient phenomena. This project lies in the cutting-edge field of astrosemantics, a branch of astroinformatics, which applies semantic technologies to astronomy. The ATELs have been used to develop an appropriate concept scheme - a representation of the information they contain - for transient astronomy using aspects of natural language processing. We demonstrate that it is possible to infer the subject of an ATEL from the vocabulary used and to identify previously unassociated reports.

Computerized Adaptive Test (CAT) Applications and Item Response Theory Models for Polytomous Items

Science.gov (United States)

Aybek, Eren Can; Demirtasli, R. Nukhet

2017-01-01

This article aims to provide a theoretical framework for computerized adaptive tests (CAT) and item response theory models for polytomous items. Besides that, it aims to introduce the simulation and live CAT software to the related researchers. Computerized adaptive test algorithm, assumptions of item response theory models, nominal response…

Testing the Neutral Theory of Biodiversity with Human Microbiome Datasets.

Science.gov (United States)

Li, Lianwei; Ma, Zhanshan Sam

2016-08-16

The human microbiome project (HMP) has made it possible to test important ecological theories for arguably the most important ecosystem to human health-the human microbiome. Existing limited number of studies have reported conflicting evidence in the case of the neutral theory; the present study aims to comprehensively test the neutral theory with extensive HMP datasets covering all five major body sites inhabited by the human microbiome. Utilizing 7437 datasets of bacterial community samples, we discovered that only 49 communities (less than 1%) satisfied the neutral theory, and concluded that human microbial communities are not neutral in general. The 49 positive cases, although only a tiny minority, do demonstrate the existence of neutral processes. We realize that the traditional doctrine of microbial biogeography "Everything is everywhere, but the environment selects" first proposed by Baas-Becking resolves the apparent contradiction. The first part of Baas-Becking doctrine states that microbes are not dispersal-limited and therefore are neutral prone, and the second part reiterates that the freely dispersed microbes must endure selection by the environment. Therefore, in most cases, it is the host environment that ultimately shapes the community assembly and tip the human microbiome to niche regime.

Astrophysical tests for the Novello-De Lorenci-Luciane theory of gravity

International Nuclear Information System (INIS)

Mosquera Cuesta, H.J.

2001-01-01

The Novello-DeLorenci-Luciane (NDL) field theory of gravitation predicts that gravitational waves (GWs) follow geodesics of a modified (effective) geometry with a speed lower than the velocity of light. The theory also demonstrates that GWs exhibit the phenomenon of birefringence, formerly believed to be exclusive of electromagnetic waves. Here prospective astrophysical tests of these predictions are proposed. I point out that future measurements of gravitational waves in coincidence with a non-gravitational process such as a neutrino burst (and likely a burst of gamma-rays) may prove useful to discriminate among all the existing theories of gravity. It is also stressed that microlensing of gravitational waves emitted by known galactic sources (i.e., pulsars) in the bulge, lensed by either the Galaxy's central black hole (Sgr A*) or a MACHO object adrift among the Milky Way's stars, may provide a clean test of the birefringence phenomenon implied by the NDL gravity theory. (author)

Cosmological tests of a scale covariant theory of gravitation

International Nuclear Information System (INIS)

Owen, J.R.

1979-01-01

The Friedmann models with #betta# = 0 are subjected to several optical and radio tests within the standard and scale covariant theories of gravitation. Within standard cosmology, both interferometric and scintillation data are interpreted in terms of selection effects and evolution. Within the context of scale covariant cosmology are derived: (1) the full solution to Einstein's gravitational equations in atomic units for a matter dominated universe, (2) the study of the magnitude vs. redshift relation for elliptical galaxies, (3) the derivation of the evolutionary parameter used in (2), (4) the isophotal angular diameter vs. redshift relation, (5) the metric angular diameter vs. redshift relation, (6) the N(m) vs. magnitude relation for QSO's and their m vs z relation, and finally (7) the integrated and differential expressions for the number count vs. radio flux test. The results, both in graphical and tabular form, are presented for four gauges (i.e. parametrized relations between atomic and gravitational units). No contradiction between the new theory and the data is found with any of the tests studied. For some gauges, which are suggested by a recent analysis of the time variation of the Moon's period which is discussed in the text in terms of the new theory, the effect of the deceleration parameter on cosmological predictions is enhanced over standard cosmology and it is possible to say that the data are more easily reconciled with an open universe. Within the same gauge, the main features of both the N(m) vs. m and m-z test are accounted for by the same simple evolutionary parametrization whereas different evolutionary rates were indicated by interpretation within standard cosmology. The same consistency, lacking in standard cosmology on this level of analysis, is achieved for the integrated and differential number count - radio flux tests within the same gauge

Strasbourg Astronomical Data Center (CDS

Directory of Open Access Journals (Sweden)

F Genova

2013-01-01

Full Text Available The Centre de Donnees astronomiques de Strasbourg (CDS, created in 1972, has been a pioneer in the dissemination of digital scientific data. Ensuring sustainability for several decades has been a major issue because science and technology evolve continuously and the data flow increases endlessly. The paper briefly describes CDS activities, major services, and its R&D strategy to take advantage of new technologies. The next frontiers for CDS are the new Web 2.0/3.0 paradigm and, at a more general level, global interoperability of astronomical on-line resources in the Virtual Observatory framework.

Proceedings of the VI Serbian-Bulgarian Astronomical Conference, May 7 - 11 2008, Belgrade, Serbia

Science.gov (United States)

Dimitrijević, M. S.; Tsvetkov, M.; Popović, L. C.; Golev, V.

2009-07-01

The Sixth Serbian-Bulgarian Astronomical Conference was organized by Belgrade Astronomical Observatory, and held in Belgrade, in the building of Mathematical Faculty in Jagiceva Street, from 75th to 11th May 2008. Co-organizers were Mathematical Faculty, Astronomical Society "Rudjer Boskovic", Institute of Astronomy of the Bulgarian Academy of Sciences (BAS), Space Research Institute of BAS and Department of Astronomy of the University of Sofia. Co-chairmen of the Scientific Organizing Committee were Milan Dimitrijevic and Milcho Tsvetkov and Co-vice chairmen Luka C. Popovic and Valeri Golev. Chair of the Local Organizing Committee was Andjelka Kovacevic. The conference [was] attended by 58 participants. From Serbia were 36, from Belgrade Astronomical Observatory, Mathematical Faculty, Faculty of Sciences from Nis, Institute of Physics from Zemum, High School for pedagogues of occupational studies from Aleksinac, Faculty of Sciences from Kragujevac, Mathematical Institute of Serbian Academy of Sciences and Arts, Astronomical Society "Rudjer Boskovic" and Astronomical Society "Magellanic Cloud." From Bulgaria were present 17 colleagues: Svetlana Boeva, Ana Borisova, Momchil Dechev, Peter Duchlev, Lostadinka Koleva, Georgi Petrov, Vasil Popov, Konstatin Stavrev, Katya Ysvetkova and Milcho Tsvetkov from Institute of Astronomy of BAS, Rumen Bogdanovski and Krasmimira Ianova from Space Research Institute of BAS, Georgi R. Ivanov, Georgi Petrov and Grigor Nikolov from Department of Astronomy, Sofia University "St Kliment Ohridski,", Yavor Chapanov from Central Laboratory for Geodesy of BAS and Petya Pavlova from Technical University of Sofia, Branch Plovdiv. Besides participants from Serbia and Bulgaria the Conference [was] attended [by] Vlado Milicevic from Canada, Jan Vondrak from Czech Republic, Aytap Sezer from Turkey and Tetyana Sergeeva and Alexandr Sergeev from Ukraine. On the Conference were presented 13 invited lectures, 22 short talks and 35 posters, in total

Astronomical Alignments in a Neolithic Chinese Site?

Science.gov (United States)

Nelson, S.; Stencel, R. E.

1997-12-01

In the Manchurian province of Liaoning, near 41N19' and 119E30', exist ruins of a middle Neolithic society (2500 to 4000 BC) known as the Hongshan culture. This location, called Niuheliang, is comprised of 16 locations with monumental structures scattered over 80 square kilometers of hills. Most are stone burial structures that contain jade artifacts implying wealth and power. One structure is unique in being unusually shaped and containing oversized effigies of goddess figures. This structure also has a commanding view of the surrounding landscape. The presence of decorated pottery, jade and worked copper suggests the Hongshan people were sophisticated artisans and engaged in long-distance trading. During 1997, we've conducted a course at Denver as part of our Core Curriculum program for upper division students, that has examined the astronomical and cultural aspects of the Niuheliang site, to attempt to determine whether these contemporaries of the builders of Stonehenge may have included astronomical alignments into their constructions. The preliminary result of our studies suggests that certain monuments have potential for lunar standstill observation from the "goddess temple". For updates on these results, please see our website: www.du.edu/ rstencel/core2103.html.

Integrating the IA2 Astronomical Archive in the VO: The VO-Dance Engine

Science.gov (United States)

Molinaro, M.; Laurino, O.; Smareglia, R.

2012-09-01

Virtual Observatory (VO) protocols and standards are getting mature and the astronomical community asks for astrophysical data to be easily reachable. This means data centers have to intensify their efforts to provide the data they manage not only through proprietary portals and services but also through interoperable resources developed on the basis of the IVOA (International Virtual Observatory Alliance) recommendations. Here we present the work and ideas developed at the IA2 (Italian Astronomical Archive) data center hosted by the INAF-OATs (Italian Institute for Astrophysics - Trieste Astronomical Observatory) to reach this goal. The core point is the development of an application that from existing DB and archive structures can translate their content to VO compliant resources: VO-Dance (written in Java). This application, in turn, relies on a database (potentially DBMS independent) to store the translation layer information of each resource and auxiliary content (UCDs, field names, authorizations, policies, etc.). The last token is an administrative interface (currently developed using the Django python framework) to allow the data center administrators to set up and maintain resources. This deployment, platform independent, with database and administrative interface highly customizable, means the package, when stable and easily distributable, can be also used by single astronomers or groups to set up their own resources from their public datasets.

The Material Culture of Nineteenth-Century Astrometry, its Circulation and Heritage at the Astronomical Observatory of Lisbon

Science.gov (United States)

Raposo, Pedro

The Astronomical Observatory of Lisbon was founded in 1857 in the sequence of a controversy on stellar parallax measurements involving astronomers from the Observatory of Paris and the Observatory of Pulkovo. The development of this discussion led the contenders to recognize Lisbon as a suitable place to carry out this kind of measurements and to foster the field of stellar astronomy. Some local actors strived to keep up with this wave of international interest and establish a first-rank astronomical institution in the Portuguese capital. In order to fulfil this goal, correspondence was intensively exchanged with leading foreign astronomers and instrument makers. Besides, a Portuguese Navy officer bound to become the first director of the new institution was commissioned to visit several observatories and instrument workshops abroad, and to spend a few years in Pulkovo as a trainee astronomer. Although founded with generous financial support from the Portuguese crown and lavishly equipped and constructed, the Observatory of Lisbon was later affected by limiting budgets and a shortage of qualified personnel. Nevertheless, local efforts to improve instruments as well as observation and calculation techniques enabled its astronomers to yield important contributions to positional astronomy, especially towards the end of the nineteenth century and the beginnings of the twentieth century. The original instruments and spaces of the Observatory of Lisbon, strongly modelled on those of Pulkovo, are very well preserved, constituting an outstanding extant example of a mid-nineteenth century advanced observatory. The history they embody testifies the connectedness of the astronomical heritage worldwide.

Training Young Astronomers in EPO: An Update on the AAS Astronomy Ambassadors Program

Science.gov (United States)

Fraknoi, A.; Fienberg, R. T.; Gurton, S.; Schmitt, A. H.; Schatz, D.; Prather, E. E.

2014-07-01

The American Astronomical Society, with organizations active in EPO, has launched professional-development workshops and a community of practice to help improve early-career astronomers' ability to communicate effectively. Called “Astronomy Ambassadors,” the program provides mentoring and training for participants, from advanced undergraduates to beginning faculty. By learning to implement effective EPO strategies, Ambassadors become better teachers, meeting presenters, and representatives of our science to the public and government. Because young astronomers are a more diverse group than those who now do most outreach, they help the astronomy community present a more multicultural and gender-balanced face to the public, enabling underserved groups to see themselves as scientists. Ambassadors are given a library of outreach activities and materials, including many developed by cooperating organizations such as the ASP, plus some that have been created by Andrew Fraknoi specifically for this program.

Towards strong field tests of beyond Horndeski gravity theories

Science.gov (United States)

Sakstein, Jeremy; Babichev, Eugeny; Koyama, Kazuya; Langlois, David; Saito, Ryo

2017-03-01

Theories of gravity in the beyond Horndeski class encompass a wide range of scalar-tensor theories that will be tested on cosmological scales over the coming decade. In this work, we investigate the possibility of testing them in the strong field regime by looking at the properties of compact objects—neutron, hyperon, and quark stars—embedded in an asymptotically de Sitter space-time, for a specific subclass of theories. We extend previous works to include slow rotation and find a relation between the dimensionless moment of inertia (I ¯ =I c2/GNM3 ) and the compactness C =GNM /R c2 (an I ¯-C relation), independent of the equation of state, that is reminiscent of but distinct from the general relativity prediction. Several of our equations of state contain hyperons and free quarks, allowing us to revisit the hyperon puzzle. We find that the maximum mass of hyperon stars can be larger than 2 M⊙ for small values of the beyond Horndeski parameter, thus providing a resolution of the hyperon puzzle based on modified gravity. Moreover, stable quark stars exist when hyperonic stars are unstable, which means that the phase transition from hyperon to quark stars is predicted just as in general relativity (GR), albeit with larger quark star masses. Two important and potentially observable consequences of some of the theories we consider are the existence of neutron stars in a range of masses significantly higher than in GR and I ¯-C relations that differ from their GR counterparts. In the former case, we find objects that, if observed, could not be accounted for in GR because they violate the usual GR causality condition. We end by discussing several difficult technical issues that remain to be addressed in order to reach more realistic predictions that may be tested using gravitational wave searches or neutron star observations.

Numerical Test of Analytical Theories for Perpendicular Diffusion in Small Kubo Number Turbulence

Energy Technology Data Exchange (ETDEWEB)

Heusen, M.; Shalchi, A., E-mail: husseinm@myumanitoba.ca, E-mail: andreasm4@yahoo.com [Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2 (Canada)

2017-04-20

In the literature, one can find various analytical theories for perpendicular diffusion of energetic particles interacting with magnetic turbulence. Besides quasi-linear theory, there are different versions of the nonlinear guiding center (NLGC) theory and the unified nonlinear transport (UNLT) theory. For turbulence with high Kubo numbers, such as two-dimensional turbulence or noisy reduced magnetohydrodynamic turbulence, the aforementioned nonlinear theories provide similar results. For slab and small Kubo number turbulence, however, this is not the case. In the current paper, we compare different linear and nonlinear theories with each other and test-particle simulations for a noisy slab model corresponding to small Kubo number turbulence. We show that UNLT theory agrees very well with all performed test-particle simulations. In the limit of long parallel mean free paths, the perpendicular mean free path approaches asymptotically the quasi-linear limit as predicted by the UNLT theory. For short parallel mean free paths we find a Rechester and Rosenbluth type of scaling as predicted by UNLT theory as well. The original NLGC theory disagrees with all performed simulations regardless what the parallel mean free path is. The random ballistic interpretation of the NLGC theory agrees much better with the simulations, but compared to UNLT theory the agreement is inferior. We conclude that for this type of small Kubo number turbulence, only the latter theory allows for an accurate description of perpendicular diffusion.

Numerical Test of Analytical Theories for Perpendicular Diffusion in Small Kubo Number Turbulence

International Nuclear Information System (INIS)

Heusen, M.; Shalchi, A.

2017-01-01

In the literature, one can find various analytical theories for perpendicular diffusion of energetic particles interacting with magnetic turbulence. Besides quasi-linear theory, there are different versions of the nonlinear guiding center (NLGC) theory and the unified nonlinear transport (UNLT) theory. For turbulence with high Kubo numbers, such as two-dimensional turbulence or noisy reduced magnetohydrodynamic turbulence, the aforementioned nonlinear theories provide similar results. For slab and small Kubo number turbulence, however, this is not the case. In the current paper, we compare different linear and nonlinear theories with each other and test-particle simulations for a noisy slab model corresponding to small Kubo number turbulence. We show that UNLT theory agrees very well with all performed test-particle simulations. In the limit of long parallel mean free paths, the perpendicular mean free path approaches asymptotically the quasi-linear limit as predicted by the UNLT theory. For short parallel mean free paths we find a Rechester and Rosenbluth type of scaling as predicted by UNLT theory as well. The original NLGC theory disagrees with all performed simulations regardless what the parallel mean free path is. The random ballistic interpretation of the NLGC theory agrees much better with the simulations, but compared to UNLT theory the agreement is inferior. We conclude that for this type of small Kubo number turbulence, only the latter theory allows for an accurate description of perpendicular diffusion.

Astronomers Get New Tools for Gravitational-Wave Detection

Science.gov (United States)

2010-01-01

Teamwork between gamma-ray and radio astronomers has produced a breakthrough in finding natural cosmic tools needed to make the first direct detections of the long-elusive gravitational waves predicted by Albert Einstein nearly a century ago. An orbiting gamma-ray telescope has pointed radio astronomers to specific locations in the sky where they can discover new millisecond pulsars. Millisecond pulsars, rapidly-spinning superdense neutron stars, can serve as extremely precise and stable natural clocks. Astronomers hope to detect gravitational waves by measuring tiny changes in the pulsars' rotation caused by the passage of the gravitational waves. To do this, they need a multitude of millisecond pulsars dispersed widely throughout the sky. However, nearly three decades after the discovery of the first millisecond pulsar, only about 150 of them had been found, some 90 of those clumped tightly in globular star clusters and thus unusable for detecting gravitational waves. The problem was that millisecond pulsars could only be discovered through arduous, computing-intensive searches of small portions of sky. "We've probably found far less than one percent of the millisecond pulsars in the Milky Way Galaxy," said Scott Ransom of the National Radio Astronomy Observatory (NRAO). The breakthrough came when an instrument aboard NASA's Fermi Gamma-Ray Space Telescope began surveying the sky in 2008. This instrument located hundreds of gamma-ray-emitting objects throughout our Galaxy, and astronomers suspected many of these could be millisecond pulsars. Paul Ray of the Naval Research Laboratory initiated an international collaboration to use radio telescopes to confirm the identity of these objects as millisecond pulsars. "The data from Fermi were like a buried-treasure map," Ransom said. "Using our radio telescopes to study the objects located by Fermi, we found 17 millisecond pulsars in three months. Large-scale searches had taken 10-15 years to find that many," Ransom

The BOOTES-5 telescope at San Pedro Martir National Astronomical Observatory, Mexico

Science.gov (United States)

Hiriart, D.; Valdez, J.; Martínez, B.; García, B.; Cordova, A.; Colorado, E.; Guisa, G.; Ochoa, J. L.; Nuñez, J. M.; Ceseña, U.; Cunniffe, R.; Murphy, D.; Lee, W.; Park, Il H.; Castro-Tirado, A. J.

2016-12-01

BOOTES-5 is the fifth robotic observatory of the international network of robotic telescopes BOOTES (Burst Observer and Optical Transient Exploring Optical System). It is located at the National Astronomical Observatory at Sierra San Pedro Martir, Baja California, Mexico. It was dedicated on November 26, 2015 and it is in the process of testing. Its main scientific objective is the observation and monitoring of the optic counterparts of gamma-ray bursts as quickly as possible once they have been detected from space or other ground-based observatories. BOOTES-5 fue nombrado Telescopio Javier Gorosabel en memoria del astrónomo español Javier Gorosabel Urkia.

Astronomical Research with the MicroObservatory Net

Science.gov (United States)

Brecher, K.; Sadler, P.; Gould, R.; Leiker, S.; Antonucci, P.; Deutsch, F.

1997-05-01

We have developed a fully integrated automated astronomical telescope system which combines the imaging power of a cooled CCD, with a self-contained and weatherized 15 cm reflecting optical telescope and mount. The MicroObservatory Net consists of five of these telescopes. They are currently being deployed around the world at widely distributed longitudes. Remote access to the MicroObservatories over the Internet has now been implemented. Software for computer control, pointing, focusing, filter selection as well as pattern recognition have all been developed as part of the project. The telescopes can be controlled in real time or in delay mode, from a Macintosh, PC or other computer using Web-based software. The Internet address of the telescopes is http://cfa- www.harvard.edu/cfa/sed/MicroObservatory/MicroObservatory.html. In the real-time mode, individuals have access to all of the telescope control functions without the need for an `on-site' operator. Users can sign up for a specific period of ti me. In the batch mode, users can submit requests for delayed telescope observations. After a MicroObservatory completes a job, the user is automatically notified by e-mail that the image is available for viewing and downloading from the Web site. The telescopes were designed for classroom instruction, as well as for use by students and amateur astronomers for original scientific research projects. We are currently examining a variety of technical and educational questions about the use of the telescopes including: (1) What are the best approaches to scheduling real-time versus batch mode observations? (2) What criteria should be used for allocating telescope time? (3) With deployment of more than one telescope, is it advantageous for each telescope to be used for just one type of observation, i.e., some for photometric use, others for imaging? And (4) What are the most valuable applications of the MicroObservatories in astronomical research? Support for the Micro

The Astronomical Instrument, So-Gahui Invented During King Sejong Period

Science.gov (United States)

Lee, Yong-Sam Lee; Kim, Sang-Hyuk

2002-09-01

So-ganui, namely small simplified armillary sphere, was invented as an astronomical instrument by Lee Cheon, Jeong Cho, Jung In-Ji under 16 years' rule of King Sejong. We collect records and observed data on So-ganui. It is designed to measure position of celestial sphere and to determine time. It also can be transformed equatorial to horizontal, and horizontal to equatorial coordinate. It can measure the right ascension, declination, altitude and azimuth. It is composed of Sayu-hwan (Four displacements), Jeokdo-hwan (Equatorial dial), Baekgak-hwan (Ring with one hundred-interval quarters), Gyuhyeong (Sighting aliadade), Yongju (Dragon-pillar) and Bu (Stand). So-ganui was used conveniently portable surveying as well as astronomical instrument and possible to determine time during day and night.

Further tests of belief-importance theory.

Directory of Open Access Journals (Sweden)

K V Petrides

Full Text Available Belief-importance (belimp theory hypothesizes that personality traits confer a propensity to perceive convergences or divergences between the belief that we can attain certain goals and the importance that we place on these goals. Belief and importance are conceptualized as two coordinates, together defining the belimp plane. We tested fundamental aspects of the theory using four different planes based on the life domains of appearance, family, financial security, and friendship as well as a global plane combining these four domains. The criteria were from the areas of personality (Big Five and trait emotional intelligence and learning styles. Two hundred and fifty eight participants were allocated into the four quadrants of the belimp plane (Hubris, Motivation, Depression, and Apathy according to their scores on four reliable instruments. Most hypotheses were supported by the data. Results are discussed with reference to the stability of the belimp classifications under different life domains and the relationship of the quadrants with the personality traits that are hypothesized to underpin them.

Stereoscopy in Astronomical Visualizations to Support Learning at Informal Education Settings

Science.gov (United States)

Price, Aaron; Lee, Hee-Sun

2015-08-01

Stereoscopy has been used in science education for 100 years. Recent innovations in low cost technology as well as trends in the entertainment industry have made stereoscopy popular among educators and audiences alike. However, experimental studies addressing whether stereoscopy actually impacts science learning are limited. Over the last decade, we have conducted a series of quasi-experimental and experimental studies on how children and adult visitors in science museums and planetariums learned about the structure and function of highly spatial scientific objects such as galaxies, supernova, etc. We present a synthesis of the results from these studies and implications for stereoscopic visualization development. The overall finding is that the impact of stereoscopy on perceptions of scientific objects is limited when presented as static imagery. However, when presented as full motion films, a significantly positive impact was detected. To conclude, we present a set of stereoscopic design principles that can help design astronomical stereoscopic films that support deep and effective learning. Our studies cover astronomical content such as the engineering of and imagery from the Mars rovers, artistic stereoscopic imagery of nebulae and a high-resolution stereoscopic film about how astronomers measure and model the structure of our galaxy.

Leslie Peltier, Amateur Astronomer and Observer Extraordinaire

Science.gov (United States)

Corbin, B. G.

2003-12-01

Leslie Copus Peltier, (Jan. 2, 1900-May 10, 1980) was called "the world's greatest non-professional astronomer" by none other than Harlow Shapley, and also referred to as the "the world's greatest living amateur astronomer". He began observing variable stars on March 1, 1918 with an observation of R. Leonis and at the time of his death had made a total of 132,123 observations of variable stars. These were reported to the AAVSO on a consecutive monthly basis stretching from 1918 to his death in 1980. As of October 2003, he was still on AAVSO's list of the top 25 observers in its history. Born on a farm near Delphos, Ohio, his parents were well read and their home was filled with books on different subjects, including nature guides. As a young man he studied the flora and fauna of the area and in 1915 began his study of the heavens with Vega being the first star he identified. After the purchase of a 2-inch spyglass, his observations of variable stars began to be noticed by professional astronomers and the AAVSO loaned him a 4-inch Mogey refractor; shortly thereafter Henry Norris Russell of Princeton loaned him via the AAVSO a 6-inch refractor, a comet seeker of short focus. He discovered 12 comets, 10 of which carry his name, and 6 novae or recurring novae. His design of the "Merry-Go-Round Observatory" was a novel approach with the whole observatory revolving around the observer while seated in his observing chair. Miami University (Ohio) later donated to him their 12-inch Clark refractor with its dome. His first book, Starlight Nights: The Adventures of a Star-Gazer, appeared in 1965. This autobiography, an ode to the joys of observing both the night sky and nature, was written in beautifully descriptive language that helped lead countless readers into astronomy. Departing from astronomy, in 1977 he published The Place on Jennings Creek. Written in the style of the 19th century naturalist, the book was devoted to his family's home, Brookhaven, and its natural

Conducting meta-analyses of HIV prevention literatures from a theory-testing perspective.

Science.gov (United States)

Marsh, K L; Johnson, B T; Carey, M P

2001-09-01

Using illustrations from HIV prevention research, the current article advocates approaching meta-analysis as a theory-testing scientific method rather than as merely a set of rules for quantitative analysis. Like other scientific methods, meta-analysis has central concerns with internal, external, and construct validity. The focus of a meta-analysis should only rarely be merely describing the effects of health promotion, but rather should be on understanding and explaining phenomena and the processes underlying them. The methodological decisions meta-analysts make in conducting reviews should be guided by a consideration of the underlying goals of the review (e.g., simply effect size estimation or, preferably theory testing). From the advocated perspective that a health behavior meta-analyst should test theory, the authors present a number of issues to be considered during the conduct of meta-analyses.

Theories of coalition formation: An empirical test using data from Danish local government

DEFF Research Database (Denmark)

Skjæveland, Asbjørn; Serritzlew, Søren; Blom-Hansen, Jens

2007-01-01

Theories of coalition formation represent a diverse set of arguments about why some government coalitions form while others do not. In this article, the authors present a systematic empirical test of the relative importance of the various arguments. The test is designed to avoid a circularity...... problem present in many coalition studies - namely that the theories are tested on data of national government coalitions in postwar Europe: the very data that gave rise to the theories in the first place. Instead, the authors focus on government coalitions at the municipal level. They base their analysis...... on office and policy motives. At the same time, the analysis raises the question of whether actors really seek minimal coalitions....

Proposed experimental test of an alternative electrodynamic theory of superconductors

Energy Technology Data Exchange (ETDEWEB)

Hirsch, J.E., E-mail: jhirsch@ucsd.edu

2015-01-15

Highlights: • A new experimental test of electric screening in superconductors is proposed. • The electric screening length is predicted to be much larger than in normal metals. • The reason this was not seen in earlier experiments is explained. • This is not predicted by the conventional BCS theory of superconductivity. - Abstract: An alternative form of London’s electrodynamic theory of superconductors predicts that the electrostatic screening length is the same as the magnetic penetration depth. We argue that experiments performed to date do not rule out this alternative formulation and propose an experiment to test it. Experimental evidence in its favor would have fundamental implications for the understanding of superconductivity.

Mingantu, 18th-Century Mongol Astronomer and Radioheliograph Namesake

Science.gov (United States)

Pasachoff, Jay M.

2013-01-01

The 18th-century Mongol astronomer Mingantu (1692-1765) has been honored with a city named after him and a nearby solar telescope array. During the IAU/Beijing, my wife and I went to the new Chinese solar radioheliograph, the Mingantu Observing Station, in Inner Mongolia, ~400 km northwest of Beijing, a project of the National Astronomical Observatories, Chinese Academy of Sciences. It currently contains 40 dishes each 4.5 m across, with a correlator from Beijing. Within a year, 60 2-m dishes will be added. We passed by the 12-century ruins of Xanadu (about 20 km north of Zhangbei) about halfway. The radioheliograph is in a plane about 1 km across, forming a three-armed spiral for interferometric solar mapping, something colleagues and I had carried out with the Jansky Very Large Array, taking advantage of the lunar occultation before annularity at the 20 May 2012 solar eclipse. In the central square of Mingantu city, a statue ~10-m high of the Mongol astronomer Mingantu appears. Its base bears a plaque ~1-m high of IAU Minor Planet Circular MPC 45750 announcing the naming in 2002 of asteroid 28242 Mingantu, discovered at a Chinese observatory in 1999. Mingantu carried out orbital calculations, mapping, mathematical work on infinite series, and other scientific research. He is honored by a modern museum behind the statue. The museum's first 40% describes Mingantu and his work, and is followed by some artifacts of the region from thousands of years ago. The final, large room contains a two-meter-square scale model of the radioheliograph, flat-screen televisions running Solar Dynamics Observatory and other contemporary visualizations, orreries and other objects, and large transparencies of NASA and other astronomical imagery. See my post at http://www.skyandtelescope.com/community/skyblog/newsblog/ specfically Astro-Sightseeing_in_Inner_Mongolia-167712965.html. We thank Yihua Yan for arranging the visit and Wang Wei (both NAOC) for accompanying us. My solar research

Horizontal unification as the phenomenology of the theory of open-quotes everythingclose quotes

International Nuclear Information System (INIS)

Sakharov, A.S.; Khlopov, M.Yu.

1994-01-01

It is shown that the extension of the standard model of electroweak interaction and QCD, which includes spontaneously broken horizontal local gauge symmetry, provides a quantitatively definite phenomenological description for almost all phenomena in particle physics and modern cosmology. In this model, the predictions of the standard model are combined with a description of the mass spectrum and mixing of quarks and leptons, and with the predictions of the neutrino mass spectrum and parameters of an invisible axion. This model also gives a quantitatively definite physical basis for the theory of inflation, baryosynthesis, and dark matter of the Universe. A complex analysis of physical, cosmological, and astrophysical predictions of the model singles out a narrow range of allowed values of parameters corresponding to the open-quotes effectiveclose quotes mixed cold-hot version of the theory describing the formation of the structure of the Universe. The combination of experimental and astronomical tests of the model that ensure its unambiguous verification is indicated. 34 refs

This Month in Astronomical History: Providing Context for the Advancement of Astronomy

Science.gov (United States)

Wilson, Teresa

2018-01-01

This Month in Astronomical History is a short (~500 word) illustrated column hosted on the AAS website (https://had.aas.org/resources/astro-history). Its mission is to highlight people and events that have shaped the development of astronomy to convey a historical context to current researchers, to provide a resource for education and public outreach programs seeking to incorporate a historical perspective, and to share the excitement of astronomy with the public. Knowing how the astronomical journey has proceeded thus far allows current professionals to map where to go next and how to get there. The column charts the first part of this journey by celebrating anniversaries of births, discoveries, and deaths, and the technological advances that made discoveries possible. A new “Further Reading” section encourages readers to pursue subjects in greater depth and strengthens the articles as classroom resources.In the months preceding the 21 August 2017 solar eclipse, the column featured astronomical bodies that come between Earth and the Sun: 2004 Venus transit, the 1878 solar eclipse, and the search for the hypothetical planet Vulcan. Venusian transits were an early but technically challenging way to measure the astronomical unit, now easily done with radar-ranging. Like this year’s event, eclipse chasing and citizen science were part of the 1878 experience. Newton’s Laws seemed to require a planet inside Mercury’s orbit, but General Relativity explained the behavior of Mercury without it. Studying each of these transiting bodies has expanded our knowledge and understanding of the universe differently. Transiting extrasolar planets remain to be explored in a future column. In September, an article on the discovery of Neptune followed the discussion of the non-existent Vulcan quite naturally and expanded on the brief mention of this event in relation to the discovery of Pluto. Suggestions for additional topics are always welcome.The Dudley Observatory

Overview of classical test theory and item response theory for the quantitative assessment of items in developing patient-reported outcomes measures.

Science.gov (United States)

Cappelleri, Joseph C; Jason Lundy, J; Hays, Ron D

2014-05-01

The US Food and Drug Administration's guidance for industry document on patient-reported outcomes (PRO) defines content validity as "the extent to which the instrument measures the concept of interest" (FDA, 2009, p. 12). According to Strauss and Smith (2009), construct validity "is now generally viewed as a unifying form of validity for psychological measurements, subsuming both content and criterion validity" (p. 7). Hence, both qualitative and quantitative information are essential in evaluating the validity of measures. We review classical test theory and item response theory (IRT) approaches to evaluating PRO measures, including frequency of responses to each category of the items in a multi-item scale, the distribution of scale scores, floor and ceiling effects, the relationship between item response options and the total score, and the extent to which hypothesized "difficulty" (severity) order of items is represented by observed responses. If a researcher has few qualitative data and wants to get preliminary information about the content validity of the instrument, then descriptive assessments using classical test theory should be the first step. As the sample size grows during subsequent stages of instrument development, confidence in the numerical estimates from Rasch and other IRT models (as well as those of classical test theory) would also grow. Classical test theory and IRT can be useful in providing a quantitative assessment of items and scales during the content-validity phase of PRO-measure development. Depending on the particular type of measure and the specific circumstances, the classical test theory and/or the IRT should be considered to help maximize the content validity of PRO measures. Copyright © 2014 Elsevier HS Journals, Inc. All rights reserved.

Novel Algorithms for Astronomical Plate Analyses Rene Hudec1,2 ...

Indian Academy of Sciences (India)

2Czech Technical University in Prague, Faculty of Electrical Engineering, Technicka 2,. Prague 6 ... Abstract. Powerful computers and dedicated software allow effective data mining and scientific analyses in astronomical plate archives. We.

SIP: A Web-Based Astronomical Image Processing Program

Science.gov (United States)

Simonetti, J. H.

1999-12-01

I have written an astronomical image processing and analysis program designed to run over the internet in a Java-compatible web browser. The program, Sky Image Processor (SIP), is accessible at the SIP webpage (http://www.phys.vt.edu/SIP). Since nothing is installed on the user's machine, there is no need to download upgrades; the latest version of the program is always instantly available. Furthermore, the Java programming language is designed to work on any computer platform (any machine and operating system). The program could be used with students in web-based instruction or in a computer laboratory setting; it may also be of use in some research or outreach applications. While SIP is similar to other image processing programs, it is unique in some important respects. For example, SIP can load images from the user's machine or from the Web. An instructor can put images on a web server for students to load and analyze on their own personal computer. Or, the instructor can inform the students of images to load from any other web server. Furthermore, since SIP was written with students in mind, the philosophy is to present the user with the most basic tools necessary to process and analyze astronomical images. Images can be combined (by addition, subtraction, multiplication, or division), multiplied by a constant, smoothed, cropped, flipped, rotated, and so on. Statistics can be gathered for pixels within a box drawn by the user. Basic tools are available for gathering data from an image which can be used for performing simple differential photometry, or astrometry. Therefore, students can learn how astronomical image processing works. Since SIP is not part of a commercial CCD camera package, the program is written to handle the most common denominator image file, the FITS format.

Unveiling galaxies the role of images in astronomical discovery

CERN Document Server

Roy, Jean-René

2017-01-01

Galaxies are known as the building blocks of the universe, but arriving at this understanding has been a thousand-year odyssey. This journey is told through the lens of the evolving use of images as investigative tools. Initial chapters explore how early insights developed in line with new methods of scientific imaging, particularly photography. The volume then explores the impact of optical, radio and x-ray imaging techniques. The final part of the story discusses the importance of atlases of galaxies; how astronomers organised images in ways that educated, promoted ideas and pushed for new knowledge. Images that created confusion as well as advanced knowledge are included to demonstrate the challenges faced by astronomers and the long road to understanding galaxies. By examining developments in imaging, this text places the study of galaxies in its broader historical context, contributing to both astronomy and the history of science.

Testing the non-locality of quantum theory in two-kaon systems

Energy Technology Data Exchange (ETDEWEB)

Eberhard, P.H. (California Univ., Berkeley (United States). Lawrence Berkeley Lab.)

1993-06-07

An idea for testing the non-local character of quantum theory in systems made of two neutral kaons is suggested. Such tests require detecting two long-lived or two short-lived neutral kaons in coincidence, when copper slabs are either interposed on or removed from their paths. They may be performed at an asymmetric [Phi][sup 0]-factory. They could answer some questions raised by the EPR paradox and Bell's inequalities. If such tests are performed and if predictions of quantum mechanics and standard theory of kaon regeneration are verified experimentally, all descriptions of the relevant phenomena in terms of local interactions will be ruled out in principle with the exception of very peculiar ones, which imply the existence of hidden variables, of different kinds of kaons corresponding to different values of the hidden variables, and, for some of these kaons, of regeneration probabilities enhanced by a factor of the order of 400 or more over the average. Of course, the experiment may also reveal a break down of quantum theory. (orig.)

Comment on a proposed ''crucial experiment'' to test Einstein's special theory of relativity

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Jr, W A [Universidade Estadual de Campinas (Brazil); Buonamano, V [Universidade Estadual de Campinas (Brazil). Instituto de Matematica

1976-08-11

A proposed ''crucial experiment'' to test Einstein's special theory of relativity is analysed and it is shown that it falls into the set of unsatisfactory proposals that attempt to make an experimental distinction between Einstein's special theory of relativity and a ''Lorentzian type'' special theory of relativity.

Radio and Optical Telescopes for School Students and Professional Astronomers

Science.gov (United States)

Hosmer, Laura; Langston, G.; Heatherly, S.; Towner, A. P.; Ford, J.; Simon, R. S.; White, S.; O'Neil, K. L.; Haipslip, J.; Reichart, D.

2013-01-01

The NRAO 20m telescope is now on-line as a part of UNC's Skynet worldwide telescope network. The NRAO is completing integration of radio astronomy tools with the Skynet web interface. We present the web interface and astronomy projects that allow students and astronomers from all over the country to become Radio Astronomers. The 20 meter radio telescope at NRAO in Green Bank, WV is dedicated to public education and also is part of an experiment in public funding for astronomy. The telescope has a fantastic new web-based interface, with priority queuing, accommodating priority for paying customers and enabling free use of otherwise unused time. This revival included many software and hardware improvements including automatic calibration and improved time integration resulting in improved data processing, and a new ultra high resolution spectrometer. This new spectrometer is optimized for very narrow spectral lines, which will allow astronomers to study complex molecules and very cold regions of space in remarkable detail. In accordance with focusing on broader impacts, many public outreach and high school education activities have been completed with many confirmed future activities. The 20 meter is now a fully automated, powerful tool capable of professional grade results available to anyone in the world. Drop by our poster and try out real-time telescope control!

Testing Modified Gravity Theories via Wide Binaries and GAIA

Science.gov (United States)

Pittordis, Charalambos; Sutherland, Will

2018-06-01

The standard ΛCDM model based on General Relativity (GR) including cold dark matter (CDM) is very successful at fitting cosmological observations, but recent non-detections of candidate dark matter (DM) particles mean that various modified-gravity theories remain of significant interest. The latter generally involve modifications to GR below a critical acceleration scale ˜10-10 m s-2. Wide-binary (WB) star systems with separations ≳ 5 kAU provide an interesting test for modified gravity, due to being in or near the low-acceleration regime and presumably containing negligible DM. Here, we explore the prospects for new observations pending from the GAIA spacecraft to provide tests of GR against MOND or TeVes-like theories in a regime only partially explored to date. In particular, we find that a histogram of (3D) binary relative velocities, relative to equilibrium circular velocity predicted from the (2D) projected separation predicts a rather sharp feature in this distribution for standard gravity, with an 80th (90th) percentile value close to 1.025 (1.14) with rather weak dependence on the eccentricity distribution. However, MOND/TeVeS theories produce a shifted distribution, with a significant increase in these upper percentiles. In MOND-like theories without an external field effect, there are large shifts of order unity. With the external field effect included, the shifts are considerably reduced to ˜0.04 - 0.08, but are still potentially detectable statistically given reasonably large samples and good control of contaminants. In principle, followup of GAIA-selected wide binaries with ground-based radial velocities accurate to ≲ 0.03 { km s^{-1}} should be able to produce an interesting new constraint on modified-gravity theories.

An Information Retrieval and Recommendation System for Astronomical Observatories

Science.gov (United States)

Mukund, Nikhil; Thakur, Saurabh; Abraham, Sheelu; Aniyan, A. K.; Mitra, Sanjit; Sajeeth Philip, Ninan; Vaghmare, Kaustubh; Acharjya, D. P.

2018-03-01

We present a machine-learning-based information retrieval system for astronomical observatories that tries to address user-defined queries related to an instrument. In the modern instrumentation scenario where heterogeneous systems and talents are simultaneously at work, the ability to supply people with the right information helps speed up the tasks for detector operation, maintenance, and upgradation. The proposed method analyzes existing documented efforts at the site to intelligently group related information to a query and to present it online to the user. The user in response can probe the suggested content and explore previously developed solutions or probable ways to address the present situation optimally. We demonstrate natural language-processing-backed knowledge rediscovery by making use of the open source logbook data from the Laser Interferometric Gravitational Observatory (LIGO). We implement and test a web application that incorporates the above idea for LIGO Livingston, LIGO Hanford, and Virgo observatories.

A SURVEY OF ASTRONOMICAL RESEARCH: A BASELINE FOR ASTRONOMICAL DEVELOPMENT

International Nuclear Information System (INIS)

Ribeiro, V. A. R. M.; Russo, P.; Cárdenas-Avendaño, A.

2013-01-01

Measuring scientific development is a difficult task. Different metrics have been put forward to evaluate scientific development; in this paper we explore a metric that uses the number of peer-reviewed, and when available non-peer-reviewed, research articles as an indicator of development in the field of astronomy. We analyzed the available publication record, using the Smithsonian Astrophysical Observatory/NASA Astrophysics Database System, by country affiliation in the time span between 1950 and 2011 for countries with a gross national income of less than 14,365 USD in 2010. This represents 149 countries. We propose that this metric identifies countries in ''astronomical development'' with a culture of research publishing. We also propose that for a country to develop in astronomy, it should invest in outside expert visits, send its staff abroad to study, and establish a culture of scientific publishing. Furthermore, we propose that this paper may be used as a baseline to measure the success of major international projects, such as the International Year of Astronomy 2009

Analysis of North Korea's Nuclear Tests under Prospect Theory

Energy Technology Data Exchange (ETDEWEB)

Lee, Han Myung; Ryu, Jae Soo; Lee, Kwang Seok; Lee, Dong Hoon; Jun, Eunju; Kim, Mi Jin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2013-10-15

North Korea has chosen nuclear weapons as the means to protect its sovereignty. Despite international society's endeavors and sanctions to encourage North Korea to abandon its nuclear ambition, North Korea has repeatedly conducted nuclear testing. In this paper, the reason for North Korea's addiction to a nuclear arsenal is addressed within the framework of cognitive psychology. The prospect theory addresses an epistemological approach usually overlooked in rational choice theories. It provides useful implications why North Korea, being under a crisis situation has thrown out a stable choice but taken on a risky one such as nuclear testing. Under the viewpoint of prospect theory, nuclear tests by North Korea can be understood as follows: The first nuclear test in 2006 is seen as a trial to escape from loss areas such as financial sanctions and regime threats; the second test in 2009 was interpreted as a consequence of the strategy to recover losses by making a direct confrontation against the United States; and the third test in 2013 was understood as an attempt to strengthen internal solidarity after Kim Jong-eun inherited the dynasty, as well as to enhance bargaining power against the United States. Thus, it can be summarized that Pyongyang repeated its nuclear tests to escape from a negative domain and to settle into a positive one. In addition, in the future, North Korea may not be willing to readily give up its nuclear capabilities to ensure the survival of its own regime.

astroplan: Observation Planning for Astronomers

Science.gov (United States)

Morris, Brett

2016-03-01

Astroplan is an observation planning package for astronomers. It is an astropy-affiliated package which began as a Google Summer of Code project. Astroplan facilitates convenient calculation of common observational quantities, like target altitudes and azimuths, airmasses, and rise/set times. Astroplan also computes when targets are observable given various extensible observing constraints, for example: within a range of airmasses or altitudes, or at a given separation from the Moon. Astroplan is taught in the undergraduate programming for astronomy class, and enables observational Pre- MAP projects at the University of Washington. In the near future, we plan to implement scheduling capabilities in astroplan on top of the constraints framework.

Visualizing Astronomical Data with Blender

Science.gov (United States)

Kent, Brian R.

2014-01-01

We present methods for using the 3D graphics program Blender in the visualization of astronomical data. The software's forte for animating 3D data lends itself well to use in astronomy. The Blender graphical user interface and Python scripting capabilities can be utilized in the generation of models for data cubes, catalogs, simulations, and surface maps. We review methods for data import, 2D and 3D voxel texture applications, animations, camera movement, and composite renders. Rendering times can be improved by using graphic processing units (GPUs). A number of examples are shown using the software features most applicable to various kinds of data paradigms in astronomy.

The Educational Activities of the Astronomical Society of the Pacific.

Science.gov (United States)

Fraknoi, Andrew

1981-01-01

Describes educational activities of the Astronomical Society of the Pacific including learning packets on various astronomy concepts, Morrison lectures, newspaper columns, teacher workshops, cosponsoring astronomy oriented lectures, and providing speakers for various groups. (DS)

Radio Astronomers Set New Standard for Accurate Cosmic Distance Measurement

Science.gov (United States)

1999-06-01

A team of radio astronomers has used the National Science Foundation's Very Long Baseline Array (VLBA) to make the most accurate measurement ever made of the distance to a faraway galaxy. Their direct measurement calls into question the precision of distance determinations made by other techniques, including those announced last week by a team using the Hubble Space Telescope. The radio astronomers measured a distance of 23.5 million light-years to a galaxy called NGC 4258 in Ursa Major. "Ours is a direct measurement, using geometry, and is independent of all other methods of determining cosmic distances," said Jim Herrnstein, of the National Radio Astronomy Observatory (NRAO) in Socorro, NM. The team says their measurement is accurate to within less than a million light-years, or four percent. The galaxy is also known as Messier 106 and is visible with amateur telescopes. Herrnstein, along with James Moran and Lincoln Greenhill of the Harvard- Smithsonian Center for Astrophysics; Phillip Diamond, of the Merlin radio telescope facility at Jodrell Bank and the University of Manchester in England; Makato Inoue and Naomasa Nakai of Japan's Nobeyama Radio Observatory; Mikato Miyoshi of Japan's National Astronomical Observatory; Christian Henkel of Germany's Max Planck Institute for Radio Astronomy; and Adam Riess of the University of California at Berkeley, announced their findings at the American Astronomical Society's meeting in Chicago. "This is an incredible achievement to measure the distance to another galaxy with this precision," said Miller Goss, NRAO's Director of VLA/VLBA Operations. "This is the first time such a great distance has been measured this accurately. It took painstaking work on the part of the observing team, and it took a radio telescope the size of the Earth -- the VLBA -- to make it possible," Goss said. "Astronomers have sought to determine the Hubble Constant, the rate of expansion of the universe, for decades. This will in turn lead to an

Strategies for personnel sustainable lifecycle at astronomical observatories and local industry development

Science.gov (United States)

Bendek, Eduardo A.; Leatherbee, Michael; Smith, Heather; Strappa, Valentina; Zinnecker, Hans; Perez, Mario

2014-08-01

Specialized manpower required to efficiently operate world-class observatories requires large investments in time and resources to train personnel in very specific areas of engineering. Isolation and distances to mayor cities pose a challenge to retain motivated and qualified personnel on the mountain. This paper presents strategies that we believe may be effective for retaining this specific know-how in the astronomy field; while at the same time develop a local support industry for observatory operations and astronomical instrumentation development. For this study we choose Chile as a research setting because it will host more than 60% of the world's ground based astronomical infrastructure by the end of the decade, and because the country has an underdeveloped industry for astronomy services. We identify the astronomical infrastructure that exists in the country as well as the major research groups and industrial players. We further identify the needs of observatories that could be outsourced to the local economy. As a result, we suggest spin-off opportunities that can be started by former observatory employees and therefore retaining the knowhow of experienced people that decide to leave on-site jobs. We also identify tools to facilitate this process such as the creation of a centralized repository of local capabilities and observatory needs, as well as exchange programs within astronomical instrumentation groups. We believe that these strategies will contribute to a positive work environment at the observatories, reduce the operation and development costs, and develop a new industry for the host country.

Partnerships between Professional and Amateur Astronomers: A Shift in Research Paradigm

Science.gov (United States)

Yanamandra-Fisher, Padma A.; Orton, G. S.; Casquinha, P.; Coffelt, A.; Delcroix, M.; Go, C.; Hueso, R.; Jaeschke, W.; Kardasis, M.; Kraaikamp, E.; Morales, E.; Peach, D.; Rogers, J.; Wesley, A.; Willems, F.; Wilson, T.

2012-10-01

"Citizen Astronomy" can be thought of as the paradigm shift transforming the nature of observational astronomy. The night sky, with all its delights and mysteries, enthralls professional and amateur astronomers, and students who will form the next generation of scientists and engineers. These students are matriculating in an era of reduced funding for core competencies such as science, technology, mathematics and engineering (STEM) sciences and an ongoing general decline in these sciences. How then do we re-generate their interest and engage students while we perform cutting-edge planetary science in a fiscally constrained environment? One promising solution is to promote the emerging partnerships between professional and dedicated proficient amateur astronomers, that rely on creating a niche for long timeline of multispectral remote sensing. In the past decade, it is the collective observations and their analyses by the ever-increasing global network of amateur astronomers that has discovered interesting phenomena and provided the reference backdrop for observations by professional ground-based professional astronomers and spacecraft missions. We shall focus on our collaboration or "Citizen Astronomy: Jupiter and Saturn" for the past five years and illustrate the strong synergy between the two groups that has produced new scientific results. With the active inclusion and use of emerging social media (Facebook, Twitter, etc.), the near daily communication and updates (via email, Skype, Facebook) between the two groups is becoming a powerful tool for ground-based remote sensing. However, what is sorely lacking in this paradigm is the inclusion of teachers and students and, therefore, its inclusion in the secondary and tertiary classrooms. We will provide various scenarios to address this issue, and emphasize the various aspects of STEM learning/teaching that is necessary for students and teachers - all that can be performed at low cost; and showcase some of our

The NASA Astrophysics Data System Free Access to the Astronomical Literature On-Line and through Email

CERN Document Server

Eichhorn, G; Grant, C S; Kurtz, M J; Murray, S S

2001-01-01

The Astrophysics Data System (ADS) provides access to the astronomical literature through the World Wide Web. It is a NASA funded project and access to all the ADS services is free to everybody world-wide.The ADS Abstract Service allows the searching of four databases with abstracts in Astronomy, Instrumentation, Physics/Geophysics, and the LANL Preprints with a total of over 2.2 million references. The system also provides access to reference and citation information, links to on-line data, electronic journal articles, and other on-line information. The ADS Article Service contains the articles for most of the astronomical literature back to volume 1. It contains the scanned pages of all the major journals (Astrophysical Journal, Astronomical Journal, Astronomy & Astrophysics, Monthly Notices of the Royal Astronomical Society, and Solar Physics), as well as most smaller journals back to volume 1. The ADS can be accessed through any web browser without signup or login. Alternatively an email interface is ...

Professional- Amateur Astronomer Partnerships in Scientific Research: The Re-emergence of Jupiter's 5-Micron Hot Spots

Science.gov (United States)

Yanamandra-Fisher, P. A.

2012-12-01

The night sky, with all its delights and mysteries, enthrall professional and amateur astronomers alike. The discrete data sets acquired by professional astronomers via their approved observing programs at various national facilities are supplemented by the nearly daily observations of the same celestial object by amateur astronomers around the world. The emerging partnerships between professional and dedicated amateur astronomers rely on creating a niche for long timeline of multispectral remote sensing. "Citizen Astronomy" can be thought of as the paradigm shift transforming the nature of observational astronomy. In the past decade, it is the collective observations and their analyses by the ever-increasing global network of amateur astronomers that has discovered interesting phenomena and provided the reference backdrop for observations by ground-based professional astronomers and spacecraft missions. We shall present results from our collaborations to observe the recent global upheaval on Jupiter for the past five years and illustrate the strong synergy between the two groups. Global upheavals on Jupiter involve changes in the albedo of entire axisymmetric regions, lasting several years, with the last two occurring in 1989 and 2006. Against this backdrop of planetary-scale changes, discrete features such as the Great Red Spot (GRS), and other vortices exhibit changes on shorter spatial- and time-scales. One set of features we are currently tracking is the variability of the discrete equatorial 5-μm hot spots, semi-evenly spaced in longitude and confined to a narrow latitude band centered at 6.5°N (southern edge of the North Equatorial Belt, NEB), abundant in Voyager images (1980-1981). Tantalizingly similar patterns were observed in the visible (bright plumes and blue-gray regions), where reflectivity in the red is anti-correlated with 5-μm thermal radiance. During the recent NEB fade (2011 - early 2012), however, these otherwise ubiquitous features were

World's fastest and most sensitive astronomical camera

Science.gov (United States)

2009-06-01

The next generation of instruments for ground-based telescopes took a leap forward with the development of a new ultra-fast camera that can take 1500 finely exposed images per second even when observing extremely faint objects. The first 240x240 pixel images with the world's fastest high precision faint light camera were obtained through a collaborative effort between ESO and three French laboratories from the French Centre National de la Recherche Scientifique/Institut National des Sciences de l'Univers (CNRS/INSU). Cameras such as this are key components of the next generation of adaptive optics instruments of Europe's ground-based astronomy flagship facility, the ESO Very Large Telescope (VLT). ESO PR Photo 22a/09 The CCD220 detector ESO PR Photo 22b/09 The OCam camera ESO PR Video 22a/09 OCam images "The performance of this breakthrough camera is without an equivalent anywhere in the world. The camera will enable great leaps forward in many areas of the study of the Universe," says Norbert Hubin, head of the Adaptive Optics department at ESO. OCam will be part of the second-generation VLT instrument SPHERE. To be installed in 2011, SPHERE will take images of giant exoplanets orbiting nearby stars. A fast camera such as this is needed as an essential component for the modern adaptive optics instruments used on the largest ground-based telescopes. Telescopes on the ground suffer from the blurring effect induced by atmospheric turbulence. This turbulence causes the stars to twinkle in a way that delights poets, but frustrates astronomers, since it blurs the finest details of the images. Adaptive optics techniques overcome this major drawback, so that ground-based telescopes can produce images that are as sharp as if taken from space. Adaptive optics is based on real-time corrections computed from images obtained by a special camera working at very high speeds. Nowadays, this means many hundreds of times each second. The new generation instruments require these

Applying modern psychometric techniques to melodic discrimination testing: Item response theory, computerised adaptive testing, and automatic item generation.

Science.gov (United States)

Harrison, Peter M C; Collins, Tom; Müllensiefen, Daniel

2017-06-15

Modern psychometric theory provides many useful tools for ability testing, such as item response theory, computerised adaptive testing, and automatic item generation. However, these techniques have yet to be integrated into mainstream psychological practice. This is unfortunate, because modern psychometric techniques can bring many benefits, including sophisticated reliability measures, improved construct validity, avoidance of exposure effects, and improved efficiency. In the present research we therefore use these techniques to develop a new test of a well-studied psychological capacity: melodic discrimination, the ability to detect differences between melodies. We calibrate and validate this test in a series of studies. Studies 1 and 2 respectively calibrate and validate an initial test version, while Studies 3 and 4 calibrate and validate an updated test version incorporating additional easy items. The results support the new test's viability, with evidence for strong reliability and construct validity. We discuss how these modern psychometric techniques may also be profitably applied to other areas of music psychology and psychological science in general.

Astronomical technology - the past and the future. Karl Schwarzschild Award Lecture 2015

Science.gov (United States)

Appenzeller, I.

2016-07-01

The past fifty years have been an epoch of impressive progress in the field of astronomical technology. Practically all the technical tools, which we use today, have been developed during that time span. While the first half of this period has been dominated by advances in the detector technologies, during the past two decades innovative telescope concepts have been developed for practically all wavelength ranges where astronomical observations are possible. Further important advances can be expected in the next few decades. Based on the experience of the past, some of the main sources of technological progress can be identified.

From research institution to astronomical museum: a history of the Stockholm Observatory

Science.gov (United States)

Yaskell, Steven Haywood

2008-07-01

The Royal Swedish Academy of Sciences (RSAS) (or Kungliga Vetenskapsakademien [KvA] in Swedish) founded 1739, opened its first permanent building, an astronomical and meteorological observatory, on 20 September 1753. This was situated at Brunkebergsåsen (formerly Observatorie Lunden, or Observatory Hill), on a high terrace in a northern quarter of Stockholm. This historic building is still sometimes called Gamla Observatoriet (the Old Observatory) and now is formally the Observatory Museum. This paper reviews the history of the Observatory from its function as a scientific astronomical institution to its relatively-recent relegation to museum status.

Astronomers Anonymous Getting Help with the Puzzles and Pitfalls of Practical Astronomy

CERN Document Server

Ringwood, Steve

2010-01-01

In this entertaining parody of letters to a typical “lonely hearts” columnist, real-life expert and long-time astronomy columnist Steve Ringwood presents a sweeping overview of common questions and problems practical and amateur astronomers face, compiled from Ringwood's own experiences in the world of astronomy. His screamingly funny comments will keep you laughing out loud throughout, so be careful of reading this book in public! Written especially for troubled astronomers, but also accessible to anyone with an interest in space or astronomy, readers will easily recognize the difficulties they face and enjoy the humor being directed at them and their science.

Nikolay N. Donitch - the astronomer

Science.gov (United States)

Gaina, Alex B.; Volyanskaya, M. Yu.

1999-08-01

The article is devoted to milestones of life and scientific activity of the eminent astronomer Nikolay Nikolaevich Donitch (Nicolae N. Donici) (1874-1956), a graduate from the Odessa (Novorossiski) university. He was a wellknown expert in the field of reseacrh of objects of Solar system. A person highly cultured, which built the first in Bessarabia (actually a part of the Republic of Moldova) observatory. He was borne in Kishinev (Chisinau) in a nobles family of notable Moldavian landersmen. N.D. graduated from the Richelieu lyceym in Odessa and afterwards, in 1897, graduated from the Odessa (Novorossiysky) University. A.K. Kononovich (1850-1910)headed the chair of astronomy and the Observatory at that time - a foremost authority in the field of astrophysics and stellar astronomy. Many of his disciples became eminent scientists of their time. N. Donitch was among them. N.D. worked till 1918 at Pulkovo Observatory and became a master in the field of studying of such phenomena as solar and lunar eclipses. To observe the Sun N.D., could afford to design and manufacture a spectroheliograph, the first in Russia, with the assistance of a famous Odessa mechanic J.A. Timchenko. This instrument enabled him to obtain topquality photos of the Sun's surface and prominences. It was mounted together with coelostat in the private observatory of N.D. , built in the village Staryie Doubossary in 1908. Besides the heliograoph, the observatory was equiped with a five inch refractor-equatorial with numerous instruments for various observations. Of the other instruments should be mentioned : "a comet triplet" - an instrument consisting of guiding refractor, a photographic camera and a spectrograph with an objective prism. N.D. was lucky enough to observe rare astronomical phenomena. He observed the transit of Mercury through the disk of the Sun on November 14, 1907 and showed the athmosphere absence around this planet, observed the Halley's comet in 1910, the bright Pons-Winneke comet

The High Road to Astronomical Photometric Precision : Differential Photometry

NARCIS (Netherlands)

Milone, E. F.; Pel, Jan Willem

2011-01-01

Differential photometry offers the most precise method for measuring the brightness of astronomical objects. We attempt to demonstrate why this should be the case, and then describe how well it has been done through a review of the application of differential techniques from the earliest visual

Penn State astronomical image processing system

International Nuclear Information System (INIS)

Truax, R.J.; Nousek, J.A.; Feigelson, E.D.; Lonsdale, C.J.

1987-01-01

The needs of modern astronomy for image processing set demanding standards in simultaneously requiring fast computation speed, high-quality graphic display, large data storage, and interactive response. An innovative image processing system was designed, integrated, and used; it is based on a supermicro architecture which is tailored specifically for astronomy, which provides a highly cost-effective alternative to the traditional minicomputer installation. The paper describes the design rationale, equipment selection, and software developed to allow other astronomers with similar needs to benefit from the present experience. 9 references

Far-infrared spectrophotometer for astronomical observations

Science.gov (United States)

Moseley, H.; Silverberg, R. F.

1981-01-01

A liquid-helium-cooled far infrared spectrophotometer was built and used to make low resolution observations of the continua of several kinds of astronomical objects using the Kuiper Airborne Observatory. This instrument fills a gap in both sensitivity to continuum sources and spectral resolution between the broadband photometers with lambda/Delta lambda approximately 1 and spectrometers with lambda/Delta lambda greater than 50. While designed primarily to study planetary nebulae, the instrument permits study of the shape of the continua of many weak sources which cannot easily be observed with high resolution systems.

The astronomical revolution Copernicus, Kepler, Borelli

CERN Document Server

Koyre, Alexandre

2013-01-01

Originally published in English in 1973. This volume traces the development of the revolution which so drastically altered man's view of the universe in the sixteenth and seventeenth centuries. The ""astronomical revolution"" was accomplished in three stages, each linked with the work of one man. With Copernicus, the sun became the centre of the universe. With Kepler, celestial dynamics replaced the kinematics of circles and spheres used by Copernicus. With Borelli the unification of celestial and terrestrial physics was completed by abandonment of the circle in favour the straight line to inf

Testing string theory at LHC?

CERN Multimedia

CERN. Geneva

2002-01-01

A theory with such mathematical beauty cannot be wrong: this is one of the main arguments in favour of string theory, which unifies all known physical theories of fundamental interactions in a single coherent description of the universe. But no one has ever observed strings, not even indirectly, nor the space of extra dimensions where they live. However there are good reasons to believe that the 'hidden' dimensions of string theory may be much larger than what we thought in the past and that they may be within experimental reach in the near future - together with the strings themselves. In my talk, I will give an elementary introduction of string theory and describe the main experimental predictions.Organiser(s): Jasper Kirkby / EP DivisionNote: Tea & coffee will be served at 16.00 hrs.

A generalized measurement equation and van Cittert-Zernike theorem for wide-field radio astronomical interferometry

Science.gov (United States)

Carozzi, T. D.; Woan, G.

2009-05-01

We derive a generalized van Cittert-Zernike (vC-Z) theorem for radio astronomy that is valid for partially polarized sources over an arbitrarily wide field of view (FoV). The classical vC-Z theorem is the theoretical foundation of radio astronomical interferometry, and its application is the basis of interferometric imaging. Existing generalized vC-Z theorems in radio astronomy assume, however, either paraxiality (narrow FoV) or scalar (unpolarized) sources. Our theorem uses neither of these assumptions, which are seldom fulfiled in practice in radio astronomy, and treats the full electromagnetic field. To handle wide, partially polarized fields, we extend the two-dimensional (2D) electric field (Jones vector) formalism of the standard `Measurement Equation' (ME) of radio astronomical interferometry to the full three-dimensional (3D) formalism developed in optical coherence theory. The resulting vC-Z theorem enables full-sky imaging in a single telescope pointing, and imaging based not only on standard dual-polarized interferometers (that measure 2D electric fields) but also electric tripoles and electromagnetic vector-sensor interferometers. We show that the standard 2D ME is easily obtained from our formalism in the case of dual-polarized antenna element interferometers. We also exploit an extended 2D ME to determine that dual-polarized interferometers can have polarimetric aberrations at the edges of a wide FoV. Our vC-Z theorem is particularly relevant to proposed, and recently developed, wide FoV interferometers such as Low Frequency Array (LOFAR) and Square Kilometer Array (SKA), for which direction-dependent effects will be important.

The Astronomical Pulse of Global Extinction Events

Directory of Open Access Journals (Sweden)

David F.V. Lewis

2006-01-01

Full Text Available The linkage between astronomical cycles and the periodicity of mass extinctions is reviewed and discussed. In particular, the apparent 26 million year cycle of global extinctions may be related to the motion of the solar system around the galaxy, especially perpendicular to the galactic plane. The potential relevance of Milankovitch cycles is also explored in the light of current evidence for the possible causes of extinction events over a geological timescale.

Astrophysics is easy! an introduction for the amateur astronomer

CERN Document Server

Inglis, Mike

2007-01-01

With some justification, many amateur astronomers believe astrophysics is a very difficult subject, requiring at least degree-level mathematics to understand it properly. This isn’t necessarily the case. Mike Inglis' quantitative approach to the subject explains all aspects of astrophysics in simple terms and cuts through the incomprehensible mathematics with which this fascinating subject is all too often associated. Astrophysics is Easy! begins by looking at the H-R diagram and other basic tools of astrophysics, then ranges across the universe, from a first look at the interstellar medium and nebulae, through the birth, evolution and death of stars, to the physics of galaxies and clusters of galaxies. A unique feature of this book is the way that Dr. Inglis lists example objects for practical observation at every stage, so that practical astronomers can go and look at the object or objects under discussion – using only easily-available commercial amateur equipment.

A test of prospect theory.

Science.gov (United States)

Feeny, David; Eng, Ken

2005-01-01

Prospect theory (PT) hypothesizes that people judge states relative to a reference point, usually assumed to be their current health. States better than the reference point are valued on a concave portion of the utility function; worse states are valued on a convex portion. Using prospectively collected utility scores, the objective is to test empirically implications of PT. Osteoarthritis (OA) patients undergoing total hip arthroplasty periodically provided standard gamble scores for three OA hypothetical states describing mild, moderate, and severe OA as well as their subjectively defined current state (SDCS). Our hypothesis was that most patients improved between the pre- and postsurgery assessments. According to PT, scores for hypothetical states previously > SDCS but now < SDCS should be lower at the postsurgery assessment. Fourteen patients met the criteria for testing the hypothesis. Predictions were confirmed for 0 patients; there was no change or mixed results for 6 patients (42.9 percent); and scores moved in the direction opposite to that predicted by PT for 8 patients (57.1 percent). In general, the direction and magnitude of the changes in hypothetical-state scores do not conform to the predictions of PT.

P value and the theory of hypothesis testing: an explanation for new researchers.

Science.gov (United States)

Biau, David Jean; Jolles, Brigitte M; Porcher, Raphaël

2010-03-01

In the 1920s, Ronald Fisher developed the theory behind the p value and Jerzy Neyman and Egon Pearson developed the theory of hypothesis testing. These distinct theories have provided researchers important quantitative tools to confirm or refute their hypotheses. The p value is the probability to obtain an effect equal to or more extreme than the one observed presuming the null hypothesis of no effect is true; it gives researchers a measure of the strength of evidence against the null hypothesis. As commonly used, investigators will select a threshold p value below which they will reject the null hypothesis. The theory of hypothesis testing allows researchers to reject a null hypothesis in favor of an alternative hypothesis of some effect. As commonly used, investigators choose Type I error (rejecting the null hypothesis when it is true) and Type II error (accepting the null hypothesis when it is false) levels and determine some critical region. If the test statistic falls into that critical region, the null hypothesis is rejected in favor of the alternative hypothesis. Despite similarities between the two, the p value and the theory of hypothesis testing are different theories that often are misunderstood and confused, leading researchers to improper conclusions. Perhaps the most common misconception is to consider the p value as the probability that the null hypothesis is true rather than the probability of obtaining the difference observed, or one that is more extreme, considering the null is true. Another concern is the risk that an important proportion of statistically significant results are falsely significant. Researchers should have a minimum understanding of these two theories so that they are better able to plan, conduct, interpret, and report scientific experiments.

Astronomers Detect Powerful Bursting Radio Source Discovery Points to New Class of Astronomical Objects

Science.gov (United States)

2005-03-01

Astronomers at Sweet Briar College and the Naval Research Laboratory (NRL) have detected a powerful new bursting radio source whose unique properties suggest the discovery of a new class of astronomical objects. The researchers have monitored the center of the Milky Way Galaxy for several years and reveal their findings in the March 3, 2005 edition of the journal, “Nature”. This radio image of the central region of the Milky Way Galaxy holds a new radio source, GCRT J1745-3009. The arrow points to an expanding ring of debris expelled by a supernova. CREDIT: N.E. Kassim et al., Naval Research Laboratory, NRAO/AUI/NSF Principal investigator, Dr. Scott Hyman, professor of physics at Sweet Briar College, said the discovery came after analyzing some additional observations from 2002 provided by researchers at Northwestern University. “"We hit the jackpot!” Hyman said referring to the observations. “An image of the Galactic center, made by collecting radio waves of about 1-meter in wavelength, revealed multiple bursts from the source during a seven-hour period from Sept. 30 to Oct. 1, 2002 — five bursts in fact, and repeating at remarkably constant intervals.” Hyman, four Sweet Briar students, and his NRL collaborators, Drs. Namir Kassim and Joseph Lazio, happened upon transient emission from two radio sources while studying the Galactic center in 1998. This prompted the team to propose an ongoing monitoring program using the National Science Foundation’s Very Large Array (VLA) radio telescope in New Mexico. The National Radio Astronomy Observatory, which operates the VLA, approved the program. The data collected, laid the groundwork for the detection of the new radio source. “Amazingly, even though the sky is known to be full of transient objects emitting at X- and gamma-ray wavelengths,” NRL astronomer Dr. Joseph Lazio pointed out, “very little has been done to look for radio bursts, which are often easier for astronomical objects to produce

Money Buys Financial Security and Psychological Need Satisfaction: Testing Need Theory in Affluence

Science.gov (United States)

Howell, Ryan T.; Kurai, Mark; Tam, Leona

2013-01-01

The most prominent theory to explain the curvilinear relationship between income and subjective well-being (SWB) is need theory, which proposes that increased income and wealth can lead to increased well-being in poverty because money is used to satisfy basic physiological needs. The present study tests the tenets of need theory by proposing that…

Testing alternative theories of dark matter with the CMB

International Nuclear Information System (INIS)

Li Baojiu; Barrow, John D.; Mota, David F.; Zhao, HongSheng

2008-01-01

We propose a method to study and constrain modified gravity theories for dark matter using CMB temperature anisotropies and polarization. We assume that the theories considered here have already passed the matter power-spectrum test of large-scale structure. With this requirement met, we show that a modified gravity theory can be specified by parametrizing the time evolution of its dark-matter density contrast, which is completely controlled by the dark-matter stress history. We calculate how the stress history with a given parametrization affects the CMB observables, and a qualitative discussion of the physical effects involved is supplemented with numerical examples. It is found that, in general, alternative gravity theories can be efficiently constrained by the CMB temperature and polarization spectra. There exist, however, special cases where modified gravity cannot be distinguished from the CDM model even by using both CMB and matter power spectrum observations, nor can they be efficiently restricted by other observables in perturbed cosmologies. Our results show how the stress properties of dark matter, which determine the evolutions of both density perturbations and the gravitational potential, can be effectively investigated using just the general conservation equations and without assuming any specific theoretical gravitational theory within a wide class.

Tests of Cumulative Prospect Theory with graphical displays of probability

Directory of Open Access Journals (Sweden)

Michael H. Birnbaum

2008-10-01

Full Text Available Recent research reported evidence that contradicts cumulative prospect theory and the priority heuristic. The same body of research also violates two editing principles of original prospect theory: cancellation (the principle that people delete any attribute that is the same in both alternatives before deciding between them and combination (the principle that people combine branches leading to the same consequence by adding their probabilities. This study was designed to replicate previous results and to test whether the violations of cumulative prospect theory might be eliminated or reduced by using formats for presentation of risky gambles in which cancellation and combination could be facilitated visually. Contrary to the idea that decision behavior contradicting cumulative prospect theory and the priority heuristic would be altered by use of these formats, however, data with two new graphical formats as well as fresh replication data continued to show the patterns of evidence that violate cumulative prospect theory, the priority heuristic, and the editing principles of combination and cancellation. Systematic violations of restricted branch independence also contradicted predictions of ``stripped'' prospect theory (subjectively weighted additive utility without the editing rules.

Applications of decision theory to test-based decision making

NARCIS (Netherlands)

van der Linden, Willem J.

1987-01-01

The use of Bayesian decision theory to solve problems in test-based decision making is discussed. Four basic decision problems are distinguished: (1) selection; (2) mastery; (3) placement; and (4) classification, the situation where each treatment has its own criterion. Each type of decision can be

Astronomical Data in Undergraduate courses

Science.gov (United States)

Clarkson, William I.; Swift, Carrie; Hughes, Kelli; Burke, Christopher J. F.; Burgess, Colin C.; Elrod, Aunna V.; Howard, Brittany; Stahl, Lucas; Matzke, David; Bord, Donald J.

2016-06-01

We present status and plans for our ongoing efforts to develop data analysis and problem-solving skills through Undergraduate Astronomy instruction. While our initiatives were developed with UM-Dearborn’s student body primarily in mind, they should be applicable for a wide range of institution and of student demographics. We focus here on two strands of our effort.Firstly, students in our Introductory Astronomy (ASTR 130) general-education course now perform several “Data Investigations”, in which they interrogate the Hubble Legacy Archive to illustrate important course concepts. This was motivated in part by the realization that typical public data archives now include tools to interrogate the observations that are sufficiently accessible that introductory astronomy students can use them to perform real science, albeit mostly at a descriptive level. We are continuing to refine these investigations, and, most importantly, to critically assess their effectiveness in terms of the student learning outcomes we wish to achieve. This work is supported by grant HST-EO-13758, provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.Secondly, at the advanced-undergraduate level, students taking courses in our Astronomy minor are encouraged to gain early experience in techniques of astronomical observation and analysis that are used by professionals. We present two example projects from the Fall 2015 iteration of our upper-division course ASTR330 (The Cosmic Distance Ladder), one involving Solar System measurements, the second producing calibrated aperture photometry. For both projects students conducted, analysed, and interpreted observations using our 0.4m campus telescope, and used many of the same analysis tools as professional astronomers. This work is supported partly from a Research Initiation and Seed grant from the

Testing special relativity theory using Compton scattering

International Nuclear Information System (INIS)

Contreras S, H.; Hernandez A, L.; Baltazar R, A.; Escareno J, E.; Mares E, C. A.; Hernandez V, C.; Vega C, H. R.

2010-10-01

The validity of the special relativity theory has been tested using the Compton scattering. Since 1905 several experiments has been carried out to show that time, mass, and length change with the velocity, in this work the Compton scattering has been utilized as a simple way to show the validity to relativity. The work was carried out through Monte Carlo calculations and experiments with different gamma-ray sources and a gamma-ray spectrometer with a 3 x 3 NaI (Tl) detector. The pulse-height spectra were collected and the Compton edge was observed. This information was utilized to determine the relationship between the electron's mass and energy using the Compton -knee- position, the obtained results were contrasted with two collision models between photon and electron, one model was built using the classical physics and another using the special relativity theory. It was found that calculations and experiments results fit to collision model made using the special relativity. (Author)

Quantifying the astronomical contribution to Pleistocene climate change: A non-linear, statistical approach

Science.gov (United States)

Crucifix, Michel; Wilkinson, Richard; Carson, Jake; Preston, Simon; Alemeida, Carlos; Rougier, Jonathan

2013-04-01

The existence of an action of astronomical forcing on the Pleistocene climate is almost undisputed. However, quantifying this action is not straightforward. In particular, the phenomenon of deglaciation is generally interpreted as a manifestation of instability, which is typical of non-linear systems. As a consequence, explaining the Pleistocene climate record as the addition of an astronomical contribution and noise-as often done using harmonic analysis tools-is potentially deceptive. Rather, we advocate a methodology in which non-linear stochastic dynamical systems are calibrated on the Pleistocene climate record. The exercise, though, requires careful statistical reasoning and state-of-the-art techniques. In fact, the problem has been judged to be mathematically 'intractable and unsolved' and some pragmatism is justified. In order to illustrate the methodology we consider one dynamical system that potentially captures four dynamical features of the Pleistocene climate : the existence of a saddle-node bifurcation in at least one of its slow components, a time-scale separation between a slow and a fast component, the action of astronomical forcing, and the existence a stochastic contribution to the system dynamics. This model is obviously not the only possible representation of Pleistocene dynamics, but it encapsulates well enough both our theoretical and empirical knowledge into a very simple form to constitute a valid starting point. The purpose of this poster is to outline the practical challenges in calibrating such a model on paleoclimate observations. Just as in time series analysis, there is no one single and universal test or criteria that would demonstrate the validity of an approach. Several methods exist to calibrate the model and judgement develops by the confrontation of the results of the different methods. In particular, we consider here the Kalman filter variants, the Particle Monte-Carlo Markov Chain, and two other variants of Sequential Monte

PPARC: Grid technology helps astronomers keep pace with the Universe

CERN Multimedia

2003-01-01

"Intelligent Agent" computer programs are roaming the Internet and watching the skies. These programs, using Grid computing technology, will help astronomers detect some of the most dramatic events in the universe, such as massive supernova explosions (1 page).

Laboratory measurements and astronomical search for the HSO radical.

Science.gov (United States)

Cazzoli, Gabriele; Lattanzi, Valerio; Kirsch, Till; Gauss, Jürgen; Tercero, Belén; Cernicharo, José; Puzzarini, Cristina

2016-07-01

Despite the fact that many sulfur-bearing molecules, ranging from simple diatomic species up to astronomical complex molecules, have been detected in the interstellar medium, the sulfur chemistry in space is largely unknown and a depletion in the abundance of S-containing species has been observed in the cold, dense interstellar medium (ISM). The chemical form of the missing sulfur has yet to be identified. For these reasons, in view of the fact that there is a large abundance of triatomic species harbouring sulfur, oxygen, and hydrogen, we decided to investigate the HSO radical in the laboratory to try its astronomical detection. High-resolution measurements of the rotational spectrum of the HSO radical were carried out within a frequency range well up into the THz region. Subsequently, a rigorous search for HSO in the two most studied high-mass star-forming regions, Orion KL and Sagittarius (Sgr) B2, and in the cold dark cloud Barnard 1 (B1-b) was performed. The frequency coverage and the spectral resolution of our measurements allowed us to improve and extend the existing dataset of spectroscopic parameters, thus enabling accurate frequency predictions up to the THz range. These were used to derive the synthetic spectrum of HSO, by means of the MADEX code, according to the physical parameters of the astronomical source under consideration. For all sources investigated, the lack of HSO lines above the confusion limit of the data is evident. The derived upper limit to the abundance of HSO clearly indicates that this molecule does not achieve significant abundances in either the gas phase or in the ice mantles of dust grains.

Fast and Scalable Gaussian Process Modeling with Applications to Astronomical Time Series

Science.gov (United States)

Foreman-Mackey, Daniel; Agol, Eric; Ambikasaran, Sivaram; Angus, Ruth

2017-12-01

The growing field of large-scale time domain astronomy requires methods for probabilistic data analysis that are computationally tractable, even with large data sets. Gaussian processes (GPs) are a popular class of models used for this purpose, but since the computational cost scales, in general, as the cube of the number of data points, their application has been limited to small data sets. In this paper, we present a novel method for GPs modeling in one dimension where the computational requirements scale linearly with the size of the data set. We demonstrate the method by applying it to simulated and real astronomical time series data sets. These demonstrations are examples of probabilistic inference of stellar rotation periods, asteroseismic oscillation spectra, and transiting planet parameters. The method exploits structure in the problem when the covariance function is expressed as a mixture of complex exponentials, without requiring evenly spaced observations or uniform noise. This form of covariance arises naturally when the process is a mixture of stochastically driven damped harmonic oscillators—providing a physical motivation for and interpretation of this choice—but we also demonstrate that it can be a useful effective model in some other cases. We present a mathematical description of the method and compare it to existing scalable GP methods. The method is fast and interpretable, with a range of potential applications within astronomical data analysis and beyond. We provide well-tested and documented open-source implementations of this method in C++, Python, and Julia.

Nanoscale Capillary Flows in Alumina: Testing the Limits of Classical Theory.

Science.gov (United States)

Lei, Wenwen; McKenzie, David R

2016-07-21

Anodic aluminum oxide (AAO) membranes have well-formed cylindrical channels, as small as 10 nm in diameter, in a close packed hexagonal array. The channels in AAO membranes simulate very small leaks that may be present for example in an aluminum oxide device encapsulation. The 10 nm alumina channel is the smallest that has been studied to date for its moisture flow properties and provides a stringent test of classical capillary theory. We measure the rate at which moisture penetrates channels with diameters in the range of 10 to 120 nm with moist air present at 1 atm on one side and dry air at the same total pressure on the other. We extend classical theory for water leak rates at high humidities by allowing for variable meniscus curvature at the entrance and show that the extended theory explains why the flow increases greatly when capillary filling occurs and enables the contact angle to be determined. At low humidities our measurements for air-filled channels agree well with theory for the interdiffusive flow of water vapor in air. The flow rate of water-filled channels is one order of magnitude less than expected from classical capillary filling theory and is coincidentally equal to the helium flow rate, validating the use of helium leak testing for evaluating moisture flows in aluminum oxide leaks.

The Moon in Close-up A Next Generation Astronomer's Guide

CERN Document Server

Wilkinson, John

2010-01-01

Information collected by recent space probes sent to explore the Moon by the USA, the European Space Agency, Japan, China and India has changed our knowledge and understanding of the Moon, particularly its geology, since the Apollo missions. This book presents those findings in a way that will be welcomed by amateur astronomers, students, educators and anyone interested in the Moon. Enhanced by many colour photos, it combines newly acquired scientific understanding with detailed descriptions and labelled photographic maps of the lunar surface. Guided by observation methods explained in the book and 17 Study Areas presented and carefully explained in the last chapter, amateur astronomers can observe these features from Earth using telescopes and binoculars. Readers who consult the photographic maps will gain a better understanding about the Moon’s topography and geology. The book is rounded out by a helpful glossary.

Gender, general theory of crime and computer crime: an empirical test.

Science.gov (United States)

Moon, Byongook; McCluskey, John D; McCluskey, Cynthia P; Lee, Sangwon

2013-04-01

Regarding the gender gap in computer crime, studies consistently indicate that boys are more likely than girls to engage in various types of computer crime; however, few studies have examined the extent to which traditional criminology theories account for gender differences in computer crime and the applicability of these theories in explaining computer crime across gender. Using a panel of 2,751 Korean youths, the current study tests the applicability of the general theory of crime in explaining the gender gap in computer crime and assesses the theory's utility in explaining computer crime across gender. Analyses show that self-control theory performs well in predicting illegal use of others' resident registration number (RRN) online for both boys and girls, as predicted by the theory. However, low self-control, a dominant criminogenic factor in the theory, fails to mediate the relationship between gender and computer crime and is inadequate in explaining illegal downloading of software in both boy and girl models. Theoretical implication of the findings and the directions for future research are discussed.

Astronomical Theory of Early Human Migration (Milutin Milankovic Medal Lecture)

Science.gov (United States)

Timmermann, Axel; Friedrich, Tobias

2017-04-01

Our climate system varies on a wide range of timescales, from seasons to several millions of years. A large part of this variability is internally generated as a result of instabilities of the coupled atmosphere-ocean-ice-carbon cycle system. Other modes of variability, such as glacial cycles, are caused by astronomical forcings with periods of 20, 40, 100 thousand years. These so-called Milankovitch Cycles are associated with earth's axis wobble, axis obliquity and shifts in the eccentricity of earth's orbit around the sun, respectively. When these cycles conspire, they can cause the climate system to plunge into an ice-age. This happened last time 110,000 years ago, when Northern Hemisphere summer radiation decreased substantially and ice-sheets started to form as a result. Around 100,000 years ago northern Hemisphere summer moved again closer to the sun and Homo sapiens started to leave Africa across vegetated corridors in Northeastern Africa and the Arabian Peninsula. This first migration wave must have been relatively weak, but it left unequivocal traces in the fossil and archaeological record. Why Homo sapiens embarked on its grand journey across our planet during glacial climate conditions has been subject of an intense debate in various scientific communities. Moreover, the archaeological records of an early exodus around 100 thousand years ago seem to be at odds with paleo-genetic evidences, that place the first dispersal out of Africa around 70-60 thousand years ago. To elucidate what role climate and environmental conditions played in the dispersal of Anatomically Modern Humans out of Africa, we have developed and applied one of the first integrated climate/human migration computer models. The model simulates ice-ages, abrupt climate change, the "peopling" of our planet and captures the arrival time of Homo sapiens in the Levant, Arabian Peninsula, Southern China and Australia in close agreement with paleo climate reconstructions, fossil and

Towards a robust and consistent middle Eocene astronomical timescale

Science.gov (United States)

Boulila, Slah; Vahlenkamp, Maximilian; De Vleeschouwer, David; Laskar, Jacques; Yamamoto, Yuhji; Pälike, Heiko; Kirtland Turner, Sandra; Sexton, Philip F.; Westerhold, Thomas; Röhl, Ursula

2018-03-01

Until now, the middle Eocene has remained a poorly constrained interval of efforts to produce an astrochronological timescale for the entire Cenozoic. This has given rise to a so-called "Eocene astronomical timescale gap" (Vandenberghe et al., 2012). A high-resolution astrochronological calibration for this interval has proven to be difficult to realize, mainly because carbonate-rich deep-marine sequences of this age are scarce. In this paper, we present records from middle Eocene carbonate-rich sequences from the North Atlantic Southeast Newfoundland Ridge (IODP Exp. 342, Sites U1408 and U1410), of which the cyclical sedimentary patterns allow for an orbital calibration of the geologic timescale between ∼38 and ∼48 Ma. These carbonate-rich cyclic sediments at Sites U1408 and U1410 were deposited as drift deposits and exhibit prominent lithological alternations (couplets) between greenish nannofossil-rich clay and white nannofossil ooze. The principal lithological couplet is driven by the obliquity of Earth's axial tilt, and the intensity of their expression is modulated by a cyclicity of about 173 kyr. This cyclicity corresponds to the interference of secular frequencies s3 and s6 (related to the precession of nodes of the Earth and Saturn, respectively). This 173-kyr obliquity amplitude modulation cycle is exceptionally well recorded in the XRF (X-ray fluorescence)-derived Ca/Fe ratio. In this work, we first demonstrate the stability of the (s3-s6) cycles using the latest astronomical solutions. Results show that this orbital component is stable back to at least 50 Ma, and can thus serve as a powerful geochronometer in the mid-Eocene portion of the Cenozoic timescale. We then exploit this potential by calibrating the geochronology of the recovered middle Eocene timescale between magnetic polarity Chrons C18n.1n and C21n. Comparison with previous timescales shows similarities, but also notable differences in durations of certain magnetic polarity chrons. We

Astronomical Plate Archives and Binary Blazars Studies

Czech Academy of Sciences Publication Activity Database

Hudec, René

2011-01-01

Roč. 32, 1-2 (2011), s. 91-95 ISSN 0250-6335. [Conference on Multiwavelength Variability of Blazars. Guangzhou, 22,09,2010-24,09,2010] R&D Projects: GA ČR GA205/08/1207 Grant - others:GA ČR(CZ) GA102/09/0997; MŠMT(CZ) ME09027 Institutional research plan: CEZ:AV0Z10030501 Keywords : astronomical plates * plate archives archives * binary blazars Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 0.400, year: 2011

The cross-national pattern of happiness. Test of predictions implied in three theories of happiness

NARCIS (Netherlands)

R. Veenhoven (Ruut); J.J. Ehrhardt (Joop)

1995-01-01

textabstractABSTRACT. Predictions about level and dispersion of happiness in nations are derived from three theories of happiness: comparison-theory, folklore-theory and livability-theory. The predictions are tested on two cross national data-sets: a comparative survey among university students in

Old Star's "Rebirth" Gives Astronomers Surprises

Science.gov (United States)

2005-04-01

Astronomers using the National Science Foundation's Very Large Array (VLA) radio telescope are taking advantage of a once-in-a-lifetime opportunity to watch an old star suddenly stir back into new activity after coming to the end of its normal life. Their surprising results have forced them to change their ideas of how such an old, white dwarf star can re-ignite its nuclear furnace for one final blast of energy. Sakurai's Object Radio/Optical Images of Sakurai's Object: Color image shows nebula ejected thousands of years ago. Contours indicate radio emission. Inset is Hubble Space Telescope image, with contours indicating radio emission; this inset shows just the central part of the region. CREDIT: Hajduk et al., NRAO/AUI/NSF, ESO, StSci, NASA Computer simulations had predicted a series of events that would follow such a re-ignition of fusion reactions, but the star didn't follow the script -- events moved 100 times more quickly than the simulations predicted. "We've now produced a new theoretical model of how this process works, and the VLA observations have provided the first evidence supporting our new model," said Albert Zijlstra, of the University of Manchester in the United Kingdom. Zijlstra and his colleagues presented their findings in the April 8 issue of the journal Science. The astronomers studied a star known as V4334 Sgr, in the constellation Sagittarius. It is better known as "Sakurai's Object," after Japanese amateur astronomer Yukio Sakurai, who discovered it on February 20, 1996, when it suddenly burst into new brightness. At first, astronomers thought the outburst was a common nova explosion, but further study showed that Sakurai's Object was anything but common. The star is an old white dwarf that had run out of hydrogen fuel for nuclear fusion reactions in its core. Astronomers believe that some such stars can undergo a final burst of fusion in a shell of helium that surrounds a core of heavier nuclei such as carbon and oxygen. However, the

Astronomical Heritage and Aboriginal People: Conflicts and Possibilities

Science.gov (United States)

López, Alejandro Martín

2016-10-01

In this presentation we address issues relating to the astronomical heritage of contemporary aboriginal groups and other minorities. We deal specially with intangible astronomical heritage and its particularities. Also, we study (from ethnographic experience with Aboriginal groups, Creoles and Europeans in the Argentine Chaco) the conflicts referring to the different ways in which the natives' knowledge and practice are categorized by the natives themselves, by scientists, state politicians, professional artists and NGOs. Furthermore, we address several cases that illustrate these kinds of conflicts. We aim to analyze the complexities of patrimonial policies when they are applied to practices and representations of contemporary communities involved in power relations with national states and the global system. The essentialization of identities, the folklorization of representations and practices, and the fossilization of aboriginal peoples are some of the risks of applying the label ``cultural heritage'' without a careful consideration of each specific case. In particular we suggest possible ways in which the international scientific community could collaborate to improve the agenda of national states instead of reproducing colonial prejudices. In this way, we aim to contribute to the promotion of respect for ethnic and religious minorities.

Databases of Publications and Observations as a Part of the Crimean Astronomical Virtual Observatory

Directory of Open Access Journals (Sweden)

Shlyapnikov A.

2015-12-01

Full Text Available We describe the main principles of formation of databases (DBs with information about astronomical objects and their physical characteristics derived from observations obtained at the Crimean Astrophysical Observatory (CrAO and published in the “Izvestiya of the CrAO” and elsewhere. Emphasis is placed on the DBs missing from the most complete global library of catalogs and data tables, VizieR (supported by the Center of Astronomical Data, Strasbourg. We specially consider the problem of forming a digital archive of observational data obtained at the CrAO as an interactive DB related to database objects and publications. We present examples of all our DBs as elements integrated into the Crimean Astronomical Virtual Observatory. We illustrate the work with the CrAO DBs using tools of the International Virtual Observatory: Aladin, VOPlot, VOSpec, in conjunction with the VizieR and Simbad DBs.

Testing Self-Determination Theory via Nigerian and Indian Adolescents

Science.gov (United States)

Sheldon, Kennon M.; Abad, Neetu; Omoile, Jessica

2009-01-01

We tested the generalizability of five propositions derived from Self-Determination Theory (SDT; Deci & Ryan, 2000) using school-aged adolescents living in India (N = 926) and Nigeria (N = 363). Consistent with past U.S. research, perceived teacher autonomy-support predicted students' basic need-satisfaction in the classroom and also predicted…

Item Response Theory Modeling of the Philadelphia Naming Test

Science.gov (United States)

Fergadiotis, Gerasimos; Kellough, Stacey; Hula, William D.

2015-01-01

Purpose: In this study, we investigated the fit of the Philadelphia Naming Test (PNT; Roach, Schwartz, Martin, Grewal, & Brecher, 1996) to an item-response-theory measurement model, estimated the precision of the resulting scores and item parameters, and provided a theoretical rationale for the interpretation of PNT overall scores by relating…

Astronomers Travel in Time and Space with Light

Science.gov (United States)

Mather, John C.

2016-01-01

This is an excerpt of John Mather's in a book titled: INSPIRED BY LIGHT, Reflections from the International Year of Light 2015. It was produced in January 2016 by SPIE, the European Physical Society (EPS), and The Abdus Salam International Centre for Theoretical Physics (ICTP) to commemorate the International Year of Light and Light-based Technologies 2015. The excerpt discusses how astronomers use light.

A comment on a proposed ''crucial experiment'' to test Einstein's special theory of relativity

International Nuclear Information System (INIS)

Rodrigues Jr, W.A.; Buonamano, V.

1976-01-01

A proposed ''crucial experiment'' to test Einstein's special theory of relativity is analysed and it is shown that it falls into the set of unsatisfactory proposals that attempt to make an experimental distinction between Einstein's special theory of relativity and a ''Lorentzian type'' special theory of relativity

Memory for performance feedback :a test of three self- motivation theories

OpenAIRE

Donlin, Joanne Mac

1990-01-01

The current study tests the adequacy of three self-motive theories to predict recall of performance feedback, memory sensitivity, and ratings of perceived accuracy. Self-enhancement (Jones, 1973) predicts individuals are motivated to maintain their self-esteem. Individuals will therefore recall positive relative to negative feedback and will rate positive feedback as more accurate. Self-consistency theory (Swann, 1985) predicts individuals are motivated to maintain their self-conceptions. The...

A modified Lorentz theory as a test theory of special relativity

Science.gov (United States)

Chang, T.; Torr, D. G.; Gagnon, D. R.

1988-01-01

Attention has been given recently to a modified Lorentz theory (MLT) that is based on the generalized Galilean transformation. Some explicit formulas within the framework of MLT, dealing with the one-way velocity of light, slow-clock transport, and the Doppler effect are derived. A number of typical experiments are analyzed on this basis. Results indicate that the empirical equivalence between MLT and special relativity is still maintained to second order terms. The results of previous works that predict that the MLT might be distinguished from special relativity at the third order by Doppler centrifuge tests capable of a fractional frequency detection threshold of 10 to the -15th are confirmed.

Progress on the New York State Observatory: a new 12-meter astronomical telescope

Science.gov (United States)

Sebring, T.; O'Dea, C.; Baum, S.; Teran, J.; Loewen, N.; Stutzki, C.; Egerman, R.; Bonomi, G.

2014-07-01

Over the past two years, the New York Astronomical Corporation (NYAC), the business arm of the Astronomical Society of New York (ASNY), has continued planning and technical studies toward construction of a 12-meter class optical telescope for the use of all New York universities and research institutions. Four significant technical studies have been performed investigating design opportunities for the facility, the dome, the telescope optics, and the telescope mount. The studies were funded by NYAC and performed by companies who have provided these subsystems for large astronomical telescopes in the past. In each case, innovative and cost effective approaches were identified, developed, analyzed, and initial cost estimates developed. As a group, the studies show promise that this telescope could be built at historically low prices. As the project continues forward, NYAC intends to broaden the collaboration, pursue funding, to continue to develop the telescope and instrument designs, and to further define the scientific mission. The vision of a historically large telescope dedicated to all New York institutions continues to grow and find new adherents.

Numerical Test of Different Approximations Used in the Transport Theory of Energetic Particles

Science.gov (United States)

Qin, G.; Shalchi, A.

2016-05-01

Recently developed theories for perpendicular diffusion work remarkably well. The diffusion coefficients they provide agree with test-particle simulations performed for different turbulence setups ranging from slab and slab-like models to two-dimensional and noisy reduced MHD turbulence. However, such theories are still based on different analytical approximations. In the current paper we use a test-particle code to explore the different approximations used in diffusion theory. We benchmark different guiding center approximations, simplifications of higher-order correlations, and the Taylor-Green-Kubo formula. We demonstrate that guiding center approximations work very well as long as the particle's unperturbed Larmor radius is smaller than the perpendicular correlation length of the turbulence. Furthermore, the Taylor-Green-Kubo formula and the definition of perpendicular diffusion coefficients via mean square displacements provide the same results. The only approximation that was used in the past in nonlinear diffusion theory that fails is to replace fourth-order correlations by a product of two second-order correlation functions. In more advanced nonlinear theories, however, this type of approximation is no longer used. Therefore, we confirm the validity of modern diffusion theories as a result of the work presented in the current paper.

International astronomical remote present observation on IRC.

Science.gov (United States)

Ji, Kaifan; Cao, Wenda; Song, Qian

On March 6 - 7, 1997, an international astronomical remote present observation (RPO) was made on Internet Relay Chat (IRC) for the first time. Seven groups in four countries, China, United States, Canada and Great Britain, used the 1 meter telescope of Yunnan observatory together by the way of remote present observation. Within minutes, images were "On-line" by FTP, and every one was able to get them by anonymous ftp and discuss them on IRC from different widely separated sites.

Astronomically speaking a dictionary of quotations on astronomy and physics

CERN Document Server

Gaither, CC

2003-01-01

To understand the history, accomplishments, failures, and meanings of astronomy requires a knowledge of what has been said about astronomy by philosophers, novelists, playwrights, poets, scientists, and laymen. With this in mind, Astronomically Speaking: A Dictionary of Quotations on Astronomy and Physics serves as a guide to what has been said about astronomy through the ages. Containing approximately 1,550 quotations and numerous illustrations, this resource is the largest compilation of astronomy and astrophysics quotations published to date.Devoted to astronomy and the closely related areas of mathematics and physics, this resource helps form an accurate picture of these interconnected disciplines. It is designed as an aid for general readers with little knowledge of astronomy who are interested in astronomical topics. Students can use the book to increase their understanding of the complexity and richness that exists in scientific disciplines. In addition, experienced scientists will find it as a handy s...

The Red Rectangle: An Astronomical Example of Mach Bands?

Science.gov (United States)

Brecher, K.

2005-12-01

Recently, the Hubble Space Telescope (HST) produced spectacular images of the "Red Rectangle". This appears to be a binary star system undergoing recurrent mass loss episodes. The image-processed HST photographs display distinctive diagonal lightness enhancements. Some of the visual appearance undoubtedly arises from actual variations in the luminosity distribution of the light of the nebula itself, i.e., due to limb brightening. Psychophysical enhancement similar to the Vasarely or pyramid effect also seems to be involved in the visual impression conveyed by the HST images. This effect is related to Mach bands (as well as to the Chevreul and Craik-O'Brien-Cornsweet effects). The effect can be produced by stacking concentric squares (or other geometrical figures such as rectangles or hexagons) of linearly increasing or decreasing size and lightness, one on top of another. We have constructed controllable Flash applets of this effect as part of the NSF supported "Project LITE: Light Inquiry Through Experiments". They can be found in the vision section of the LITE web site at http://lite.bu.edu. Mach band effects have previously been seen in medical x-ray images. Here we report for the first time the possibility that such effects play a role in the interpretation of astronomical images. Specifically, we examine to what extent the visual impressions of the Red Rectangle and other extended astronomical objects are purely physical (photometric) in origin and to what degree they are enhanced by psychophysical processes. To help assess the relative physical and psychophysical contributions to the perceived lightness effects, we have made use of a center-surround (Difference of Gaussians) filter we developed for MatLab. We conclude that local (lateral inhibition) and longer range human visual perception effects probably do contribute to the lightness features seen in astronomical objects like the Red Rectangle. Project LITE is supported by NSF Grant # DUE-0125992.

Constructing Concept Schemes From Astronomical Telegrams Via Natural Language Clustering

Science.gov (United States)

Graham, Matthew; Zhang, M.; Djorgovski, S. G.; Donalek, C.; Drake, A. J.; Mahabal, A.

2012-01-01

The rapidly emerging field of time domain astronomy is one of the most exciting and vibrant new research frontiers, ranging in scientific scope from studies of the Solar System to extreme relativistic astrophysics and cosmology. It is being enabled by a new generation of large synoptic digital sky surveys - LSST, PanStarrs, CRTS - that cover large areas of sky repeatedly, looking for transient objects and phenomena. One of the biggest challenges facing these is the automated classification of transient events, a process that needs machine-processible astronomical knowledge. Semantic technologies enable the formal representation of concepts and relations within a particular domain. ATELs (http://www.astronomerstelegram.org) are a commonly-used means for reporting and commenting upon new astronomical observations of transient sources (supernovae, stellar outbursts, blazar flares, etc). However, they are loose and unstructured and employ scientific natural language for description: this makes automated processing of them - a necessity within the next decade with petascale data rates - a challenge. Nevertheless they represent a potentially rich corpus of information that could lead to new and valuable insights into transient phenomena. This project lies in the cutting-edge field of astrosemantics, a branch of astroinformatics, which applies semantic technologies to astronomy. The ATELs have been used to develop an appropriate concept scheme - a representation of the information they contain - for transient astronomy using hierarchical clustering of processed natural language. This allows us to automatically organize ATELs based on the vocabulary used. We conclude that we can use simple algorithms to process and extract meaning from astronomical textual data.

"Zhizneopisanie" astronomia N. N. Pavlova, im samim napisannoe %t Astronomer N. N. Pavlov's autobiography

Science.gov (United States)

Zhukov, V. Yu.

This document called by the author "the life story" is written for the human resources department. It is a document intended for the official departmental purposes. At the same time there is something facinating about this documentary testimony about the epoch and the man. This short autobiography describes the early years of the Pulkovo astronomer N. N. Pavlov that fell on hard times of the Civil War. In the years between the World War I and the World War II he was awarded Mendeleyev Prize. He defended his doctorate dissertation after the evacuation from Leningrad. He was one fo the first Pulkovo astronomers to return to Leningrad in order to start reconstruction of the observatory that had been completely ruined during the war. Astronomer N. N. Pavlov renewed the Time Service in the city. N. N. Pavlov was a successful scientist and an outstanding person, all his life was devoted to science.

Authentic Astronomical Discovery in Planetariums: Bringing Data to Domes

Science.gov (United States)

Wyatt, Ryan Jason; Subbarao, Mark; Christensen, Lars; Emmons, Ben; Hurt, Robert

2018-01-01

Planetariums offer a unique opportunity to disseminate astronomical discoveries using data visualization at all levels of complexity: the technical infrastructure to display data and a sizeable cohort of enthusiastic educators to interpret results. “Data to Dome” is an initiative the International Planetarium Society to develop our community’s capacity to integrate data in fulldome planetarium systems—including via open source software platforms such as WorldWide Telescope and OpenSpace. We are cultivating a network of planetarium professionals who integrate data into their presentations and share their content with others. Furthermore, we propose to shorten the delay between discovery and dissemination in planetariums. Currently, the “latest science” is often presented days or weeks after discoveries are announced, and we can shorten this to hours or even minutes. The Data2Dome (D2D) initiative, led by the European Southern Observatory, proposes technical infrastructure and data standards that will streamline content flow from research institutions to planetariums, offering audiences a unique opportunity to access to the latest astronomical data in near real time.

Far infrared extinction coefficients of minerals of interest for astronomical observations

International Nuclear Information System (INIS)

Hasegawa, H.

1984-01-01

Far infrared extinction coefficients of mineral grains of interest for astronomical observations have been measured. The measured mineral species are: amorphous carbon, high temperature magnesium silicates, hydrous silicates, iron oxides, and amorphous silicates. (author)

Astronomers Discover Six-Image Gravitational Lens

Science.gov (United States)

2001-08-01

An international team of astronomers has used the National Science Foundation's Very Long Baseline Array (VLBA) radio telescope and NASA's Hubble Space Telescope (HST) to discover the first gravitational lens in which the single image of a very distant galaxy has been split into six different images. The unique configuration is produced by the gravitational effect of three galaxies along the line of sight between the more-distant galaxy and Earth. Optical and Radio Images of Gravitational Lens "This is the first gravitational lens with more than four images of the background object that is produced by a small group of galaxies rather than a large cluster of galaxies," said David Rusin, who just received his Ph.D. from the University of Pennsylvania. "Such systems are expected to be extremely rare, so this discovery is an important stepping stone. Because this is an intermediate case between gravitational lenses produced by single galaxies and lenses produced by large clusters of galaxies, it will give us insights we can't get from other types of lenses," Rusin added. The gravitational lens, called CLASS B1359+154, consists of a galaxy more than 11 billion light-years away in the constellation Bootes, with a trio of galaxies more than 7 billion light-years away along the same line of sight. The more-distant galaxy shows signs that it contains a massive black hole at its core and also has regions in which new stars are forming. The gravitational effect of the intervening galaxies has caused the light and radio waves from the single, more-distant galaxy to be "bent" to form six images as seen from Earth. Four of these images appear outside the triangle formed by the three intermediate galaxies and two appear inside that triangle. "This lens system is a very interesting case to study because it is more complicated than lenses produced by single galaxies, and yet simpler than lenses produced by clusters of numerous galaxies," said Chris Kochanek of the Harvard

Brightness Variations of Sun-like Stars: The Mystery Deepens - Astronomers facing Socratic "ignorance"

Science.gov (United States)

2009-12-01

An extensive study made with ESO's Very Large Telescope deepens a long-standing mystery in the study of stars similar to the Sun. Unusual year-long variations in the brightness of about one third of all Sun-like stars during the latter stages of their lives still remain unexplained. Over the past few decades, astronomers have offered many possible explanations, but the new, painstaking observations contradict them all and only deepen the mystery. The search for a suitable interpretation is on. "Astronomers are left in the dark, and for once, we do not enjoy it," says Christine Nicholls from Mount Stromlo Observatory, Australia, lead author of a paper reporting the study. "We have obtained the most comprehensive set of observations to date for this class of Sun-like stars, and they clearly show that all the possible explanations for their unusual behaviour just fail." The mystery investigated by the team dates back to the 1930s and affects about a third of Sun-like stars in our Milky Way and other galaxies. All stars with masses similar to our Sun become, towards the end of their lives, red, cool and extremely large, just before retiring as white dwarfs. Also known as red giants, these elderly stars exhibit very strong periodic variations in their luminosity over timescales up to a couple of years. "Such variations are thought to be caused by what we call 'stellar pulsations'," says Nicholls. "Roughly speaking, the giant star swells and shrinks, becoming brighter and dimmer in a regular pattern. However, one third of these stars show an unexplained additional periodic variation, on even longer timescales - up to five years." In order to find out the origin of this secondary feature, the astronomers monitored 58 stars in our galactic neighbour, the Large Magellanic Cloud, over two and a half years. They acquired spectra using the high resolution FLAMES/GIRAFFE spectrograph on ESO's Very Large Telescope and combined them with images from other telescopes [1

Testing Error Management Theory: Exploring the Commitment Skepticism Bias and the Sexual Overperception Bias

Science.gov (United States)

Henningsen, David Dryden; Henningsen, Mary Lynn Miller

2010-01-01

Research on error management theory indicates that men tend to overestimate women's sexual interest and women underestimate men's interest in committed relationships (Haselton & Buss, 2000). We test the assumptions of the theory in face-to-face, stranger interactions with 111 man-woman dyads. Support for the theory emerges, but potential boundary…

IAU Public Astronomical Organisations Network

Science.gov (United States)

Canas, Lina; Cheung, Sze Leung

2015-08-01

The Office for Astronomy Outreach has devoted intensive means to create and support a global network of public astronomical organisations around the world. Focused on bringing established and newly formed amateur astronomy organizations together, providing communications channels and platforms for disseminating news to the global community and the sharing of best practices and resources among these associations around the world. In establishing the importance that these organizations have for the dissemination of activities globally and acting as key participants in IAU various campaigns social media has played a key role in keeping this network engaged and connected. Here we discuss the implementation process of maintaining this extensive network, the processing and gathering of information and the interactions between local active members at a national and international level.

An experimental test of the linear no-threshold theory of radiation carcinogenesis

International Nuclear Information System (INIS)

Cohen, B.L.

1990-01-01

There is a substantial body of quantitative information on radiation-induced cancer at high dose, but there are no data at low dose. The usual method for estimating effects of low-level radiation is to assume a linear no-threshold dependence. if this linear no-threshold assumption were not used, essentially all fears about radiation would disappear. Since these fears are costing tens of billions of dollars, it is most important that the linear no-threshold theory be tested at low dose. An opportunity for possibly testing the linear no-threshold concept is now available at low dose due to radon in homes. The purpose of this paper is to attempt to use this data to test the linear no-threshold theory

How to Make the Dream Come True: The Astronomers' Data Manifesto

Directory of Open Access Journals (Sweden)

Ray P Norris

2007-03-01

Full Text Available Astronomy is one of the most data-intensive of the sciences. Data technology is accelerating the quality and effectiveness of its research, and the rate of astronomical discovery is higher than ever. As a result, many view astronomy as being in a "Golden Age," and projects such as the Virtual Observatory are amongst the most ambitious data projects in any field of science. But these powerful tools will be impotent unless the data on which they operate are of matching quality. Astronomy, like other fields of science, therefore needs to establish and agree on a set of guiding principles for the management of astronomical data. To focus this process, we are constructing a "data manifesto," which proposes guidelines to maximise the rate and cost-effectiveness of scientific discovery.

An online study combining the constructs from the theory of planned behaviour and protection motivation theory in predicting intention to test for chlamydia in two testing contexts.

Science.gov (United States)

Powell, Rachael; Pattison, Helen M; Francis, Jill J

2016-01-01

Chlamydia is a common sexually transmitted infection that has potentially serious consequences unless detected and treated early. The health service in the UK offers clinic-based testing for chlamydia but uptake is low. Identifying the predictors of testing behaviours may inform interventions to increase uptake. Self-tests for chlamydia may facilitate testing and treatment in people who avoid clinic-based testing. Self-testing and being tested by a health care professional (HCP) involve two contrasting contexts that may influence testing behaviour. However, little is known about how predictors of behaviour differ as a function of context. In this study, theoretical models of behaviour were used to assess factors that may predict intention to test in two different contexts: self-testing and being tested by a HCP. Individuals searching for or reading about chlamydia testing online were recruited using Google Adwords. Participants completed an online questionnaire that addressed previous testing behaviour and measured constructs of the Theory of Planned Behaviour and Protection Motivation Theory, which propose a total of eight possible predictors of intention. The questionnaire was completed by 310 participants. Sufficient data for multiple regression were provided by 102 and 118 respondents for self-testing and testing by a HCP respectively. Intention to self-test was predicted by vulnerability and self-efficacy, with a trend-level effect for response efficacy. Intention to be tested by a HCP was predicted by vulnerability, attitude and subjective norm. Thus, intentions to carry out two testing behaviours with very similar goals can have different predictors depending on test context. We conclude that interventions to increase self-testing should be based on evidence specifically related to test context.

Comparison of model propeller tests with airfoil theory

Science.gov (United States)

Durand, William F; Lesley, E P

1925-01-01

The purpose of the investigation covered by this report was the examination of the degree of approach which may be anticipated between laboratory tests on model airplane propellers and results computed by the airfoil theory, based on tests of airfoils representative of successive blade sections. It is known that the corrections of angles of attack and for aspect ratio, speed, and interference rest either on experimental data or on somewhat uncertain theoretical assumptions. The general situation as regards these four sets of corrections is far from satisfactory, and while it is recognized that occasion exists for the consideration of such corrections, their determination in any given case is a matter of considerable uncertainty. There exists at the present time no theory generally accepted and sufficiently comprehensive to indicate the amount of such corrections, and the application to individual cases of the experimental data available is, at best, uncertain. While the results of this first phase of the investigation are less positive than had been hoped might be the case, the establishment of the general degree of approach between the two sets of results which might be anticipated on the basis of this simpler mode of application seems to have been desirable.

An astronomical age for the Bishop Tuff and concordance with radioisotopic dates

DEFF Research Database (Denmark)

Rivera, Tiffany; Zeeden, Christian; Storey, Michael

2014-01-01

The Bishop Tuff forms a key stratigraphic horizon for synchronization of Quaternary sedimentary records in North America. The unit stratigraphically overlies the Matuyama-Brunhes geomagnetic polarity reversal by several thousand years; high-precision dating of this tuff may be valuable for regional...... and global correlation of records. The Quaternary time scale is anchored by 40Ar/39Ar ages on lava flows and ash layers where available, with stage boundaries and geomagnetic reversals including astronomically tuned records. However, astronomical dating has not yet validated the high-precision 238U/206Pb...... ages, including new single crystal 40Ar/39Ar sanidine fusion analyses presented here, which demonstrates that concordance through multiple dating techniques is achievable within the Quaternary...

Categorization of alternative astronomical and scientifical conceptions of the teachers from the north coast of São Paulo

Science.gov (United States)

Gonzaga, E. P.

2016-05-01

This work deals with the analysis of scientific and alternative astronomical concepts found in the responses of teachers who teach classes Science, Geography and Physic in Basic Education (BE) of the state of the North Coast of São Paulo and how to address the alternative astronomical concepts with students from students Fundamental Education (FE) and Medium Education (ME). Bringing the legal documents regarding the Astronomy in BE, within the national and the São Paulo regions curriculum level, also with rationed researches to the teacher's formation, conceptual errors in books, knowledge non-formal spaces, alternative concepts, Astronomical studies and content analysis for fundamental theoretical. The task executed with the teachers was done via Technical Orientations (TO), promoted by the Director of Education (DE) from Caraguatatuba and region, with the premise to threat the continuous formation giving moments of discussion, practical activities and using the Digital Mobile Planetarium (DMP) with non-formal spaces of knowledge to the Astronomical studies gathering data via questions. Within the analysis of the answers analysis by the teachers, tables were created with the categories that highlight actual situations on the astronomical studies in the North Coast of São Paulo, and demarked the possible paths where the continuous formation will be followed in the future. Aspects checked in the survey were highlighted; such as teachers understand that they need continuing education; teachers have scientific astronomical views on various aspects know to teach concepts of Astronomy at BE; TO is a viable option as continued training and the use of DMP as no formal teaching and learning.

Psychodynamic theory and counseling in predictive testing for Huntington's disease.

Science.gov (United States)

Tassicker, Roslyn J

2005-04-01

This paper revisits psychodynamic theory, which can be applied in predictive testing counseling for Huntington's Disease (HD). Psychodynamic theory has developed from the work of Freud and places importance on early parent-child experiences. The nature of these relationships, or attachments are reflected in adult expectations and relationships. Two significant concepts, identification and fear of abandonment, have been developed and expounded by the psychodynamic theorist, Melanie Klein. The processes of identification and fear of abandonment can become evident in predictive testing counseling and are colored by the client's experience of growing up with a parent affected by Huntington's Disease. In reflecting on family-of-origin experiences, clients can also express implied expectations of the future, and future relationships. Case examples are given to illustrate the dynamic processes of identification and fear of abandonment which may present in the clinical setting. Counselor recognition of these processes can illuminate and inform counseling practice.

A buyer's and user's guide to astronomical telescopes and binoculars

CERN Document Server

Mullaney, James

2014-01-01

Amateur astronomers of all skill levels are always contemplating their next telescope, and this book points the way to the most suitable instruments. Similarly, those who are buying their first telescopes – and these days not necessarily a low-cost one – will be able to compare and contrast different types and manufacturers. This revised new guide provides an extensive overview of binoculars and telescopes. It includes detailed up-to-date information on sources, selection and use of virtually every major type, brand, and model on today’s market, a truly invaluable treasure-trove of information and helpful advice for all amateur astronomers. Originally written in 2006, much of the first edition is inevitably now out of date, as equipment advances and manufacturers come and go. This second edition not only updates all the existing sections but adds two new ones: Astro-imaging and Professional-Amateur collaboration. Thanks to the rapid and amazing developments that have been made in digital cameras it is...

The unforgotten sisters female astronomers and scientists before Caroline Herschel

CERN Document Server

Bernardi, Gabriella

2016-01-01

Taking inspiration from Siv Cedering’s poem in the form of a fictional letter from Caroline Herschel that refers to “my long, lost sisters, forgotten in the books that record our science”, this book tells the lives of twenty-five female scientists, with specific attention to astronomers and mathematicians. Each of the presented biographies is organized as a kind of "personal file" which sets the biographee’s life in its historical context, documents her main works, highlights some curious facts, and records citations about her. The selected figures are among the most representative of this neglected world, including such luminaries as Hypatia of Alexandra, Hildegard of Bingen, Elisabetha Hevelius, and Maria Gaetana Agnesi. They span a period of about 4000 years, from En HeduAnna, the Akkadian princess, who was one of the first recognized female astronomers, to the dawn of the era of modern astronomy with Caroline Herschel and Mary Somerville. The book will be of interest to all who wish to learn more ...

Young Star May Be Belching Spheres of Gas, Astronomers Say

Science.gov (United States)

2001-05-01

A young star more than 2,000 light-years away in the constellation Cepheus may be belching out spheres of gas, say astronomers who observed it with the National Science Foundation's Very Long Baseline Array (VLBA) radio telescope. Not only is the star ejecting spheres of gas, the researchers say, but it also may be ejecting them repeatedly, phenomena not predicted by current theories of how young stars shed matter. Cepheus A star-forming region with blowups of detail In order to remain stable while accumulating matter, young stars have to throw off some of the infalling material to avoid "spinning up" so fast they would break apart, according to current theories. Infalling matter forms a thin spinning disk around the core of the new star, and material is ejected in twin "jets" perpendicular to the plane of the disk. "Twin jets have been seen emerging from many young stars, so we are quite surprised to see evidence that this object may be ejecting not jets, but spheres of gas," said Paul T.P. Ho, an astronomer at the Harvard-Smithsonian Center for Astrophysics. The research is reported in the May 17 edition of the scientific journal Nature. The astronomers observed a complex star-forming region in Cepheus and found an arc of water molecules that act like giant celestial amplifiers to boost the strength of radio signals at a frequency of 22 GHz. Such radio-wave amplifiers, called masers, show up as bright spots readily observed with radio telescopes. "With the great ability of the VLBA to show fine detail, we could track the motions of these maser spots over a period of weeks, and saw that this arc of water molecules is expanding at nearly 20,000 miles per hour," said Ho. "This was possible because we could detect detail equivalent to seeing Lincoln's nose on a penny in Los Angeles from the distance of New York," Ho added. "These observations pushed the tremendous capabilities of the VLBA and of modern computing power to their limits. This is an extremely complex

An infrared upconverter for astronomical imaging

Science.gov (United States)

Boyd, R. W.; Townes, C. H.

1977-01-01

An imaging upconverter has been constructed which is suitable for use in the study of the thermal 10-micron radiation from astronomical sources. The infrared radiation is converted to visible radiation by mixing in a 1-cm-long proustite crystal. The phase-matched 2-kayser bandpass is tunable from 9 to 11 microns. The conversion efficiency is 2 by 10 to the -7th power and the field of view of 40 arc seconds on the sky contains several hundred picture elements, approximately diffraction-limited resolution in a large telescope. The instrument has been used in studies of the sun, moon, Mercury, and VY Canis Majoris.

A dual memory theory of the testing effect.

Science.gov (United States)

Rickard, Timothy C; Pan, Steven C

2017-06-05

A new theoretical framework for the testing effect-the finding that retrieval practice is usually more effective for learning than are other strategies-is proposed, the empirically supported tenet of which is that separate memories form as a consequence of study and test events. A simplest case quantitative model is derived from that framework for the case of cued recall. With no free parameters, that model predicts both proportion correct in the test condition and the magnitude of the testing effect across 10 experiments conducted in our laboratory, experiments that varied with respect to material type, retention interval, and performance in the restudy condition. The model also provides the first quantitative accounts of (a) the testing effect as a function of performance in the restudy condition, (b) the upper bound magnitude of the testing effect, (c) the effect of correct answer feedback, (d) the testing effect as a function of retention interval for the cases of feedback and no feedback, and (e) the effect of prior learning method on subsequent learning through testing. Candidate accounts of several other core phenomena in the literature, including test-potentiated learning, recognition versus cued recall training effects, cued versus free recall final test effects, and other select transfer effects, are also proposed. Future prospects and relations to other theories are discussed.

The Role in the Virtual Astronomical Observatory in the Era of Massive Data Sets

Science.gov (United States)

Berriman, G. Bruce; Hanisch, Robert J.; Lazio, T. Joseph W.

2012-01-01

The Virtual Observatory (VO) is realizing global electronic integration of astronomy data. One of the long-term goals of the U.S. VO project, the Virtual Astronomical Observatory (VAO), is development of services and protocols that respond to the growing size and complexity of astronomy data sets. This paper describes how VAO staff are active in such development efforts, especially in innovative strategies and techniques that recognize the limited operating budgets likely available to astronomers even as demand increases. The project has a program of professional outreach whereby new services and protocols are evaluated.

Test of atomic theory by photoelectron spectrometry with synchrotron radiation

International Nuclear Information System (INIS)

Krause, M.O.

1984-01-01

The successful combination of synchrotron radiation with electron spectrometry, accomplished at Daresbury, England and Orsay, France, made it possible to investigate sigma/sub x/ and β/sub x/ continuously over the very soft x-ray or the uv range of photon energies. The detailed and highly differentiated data resulting from this advanced experimentation put theory to a stringent test. In the interplay between theory and experiment, sophisticated Hartree Fock (HF) based models were developed which included both relativistic and many-electron effects. These theoretical models have provided us with a better insight than previously possible into the physics of the photon-atom interaction and the electronic structure and dynamics of atoms. However, critical experiments continue to be important for further improvements of theory. A number of such experiments are discussed in this presentation. The dynamic properties determined in these studies include in addition to sigma/sub x/ and β/sub x/ the spin polarization parameters. As a result the comparison between theory and experiment becomes rigorous, detailed and comprehensive. 46 references, 6 figures

Creating and enhancing digital astro images a guide for practical astronomers

CERN Document Server

Privett, Grant

2007-01-01

This book clearly examines how to create the best astronomical images possible with a digital camera. It reveals the astonishing images that can be obtained with simple equipment, the right software, and knowledge of how to use it.

The Astro-WISE approach to quality control for astronomical data

NARCIS (Netherlands)

Mc Farland, John; Helmich, Ewout M.; Valentijn, Edwin A.

We present a novel approach to quality control during the processing of astronomical data. Quality control in the Astro-WISE Information System is integral to all aspects of data handing and provides transparent access to quality estimators for all stages of data reduction from the raw image to the

Astronomy and Computing: A New Journal for the Astronomical Computing Community

Science.gov (United States)

Mann, R. G.; Accomazzi, A.; Budavári, T.; Fluke, C.; Gray, N.; O'Mullane, W.; Wicenec, A.; Wise, M.

2013-10-01

We introduce Astronomy and Computing (A&C), a new, peer-reviewed journal for the expanding community of people whose work focuses on the application of computer science and information technology within astronomy, rather than on astronomical research per se. A&C arose from a BoF discussion at the ADASS XX conference in Boston, and from the ADASS community will come many of the people who will write, referee and read the papers published in A&C. In this paper, we outline the aims and scope of A&C, together with a summary of the types of paper we envisage it publishing and the criteria that will be used to referee them, and we invite the ADASS community to help us develop these in more detail and to shape a journal that serves the astronomical computing community well.

Testing the applicability of Nernst-Planck theory in ion channels: comparisons with Brownian dynamics simulations.

Directory of Open Access Journals (Sweden)

Chen Song

Full Text Available The macroscopic Nernst-Planck (NP theory has often been used for predicting ion channel currents in recent years, but the validity of this theory at the microscopic scale has not been tested. In this study we systematically tested the ability of the NP theory to accurately predict channel currents by combining and comparing the results with those of Brownian dynamics (BD simulations. To thoroughly test the theory in a range of situations, calculations were made in a series of simplified cylindrical channels with radii ranging from 3 to 15 Å, in a more complex 'catenary' channel, and in a realistic model of the mechanosensitive channel MscS. The extensive tests indicate that the NP equation is applicable in narrow ion channels provided that accurate concentrations and potentials can be input as the currents obtained from the combination of BD and NP match well with those obtained directly from BD simulations, although some discrepancies are seen when the ion concentrations are not radially uniform. This finding opens a door to utilising the results of microscopic simulations in continuum theory, something that is likely to be useful in the investigation of a range of biophysical and nano-scale applications and should stimulate further studies in this direction.

Testing the applicability of Nernst-Planck theory in ion channels: comparisons with Brownian dynamics simulations.

Science.gov (United States)

Song, Chen; Corry, Ben

2011-01-01

The macroscopic Nernst-Planck (NP) theory has often been used for predicting ion channel currents in recent years, but the validity of this theory at the microscopic scale has not been tested. In this study we systematically tested the ability of the NP theory to accurately predict channel currents by combining and comparing the results with those of Brownian dynamics (BD) simulations. To thoroughly test the theory in a range of situations, calculations were made in a series of simplified cylindrical channels with radii ranging from 3 to 15 Å, in a more complex 'catenary' channel, and in a realistic model of the mechanosensitive channel MscS. The extensive tests indicate that the NP equation is applicable in narrow ion channels provided that accurate concentrations and potentials can be input as the currents obtained from the combination of BD and NP match well with those obtained directly from BD simulations, although some discrepancies are seen when the ion concentrations are not radially uniform. This finding opens a door to utilising the results of microscopic simulations in continuum theory, something that is likely to be useful in the investigation of a range of biophysical and nano-scale applications and should stimulate further studies in this direction.

Preparing Colorful Astronomical Images II

Science.gov (United States)

Levay, Z. G.; Frattare, L. M.

2002-12-01

We present additional techniques for using mainstream graphics software (Adobe Photoshop and Illustrator) to produce composite color images and illustrations from astronomical data. These techniques have been used on numerous images from the Hubble Space Telescope to produce photographic, print and web-based products for news, education and public presentation as well as illustrations for technical publication. We expand on a previous paper to present more detail and additional techniques, taking advantage of new or improved features available in the latest software versions. While Photoshop is not intended for quantitative analysis of full dynamic range data (as are IRAF or IDL, for example), we have had much success applying Photoshop's numerous, versatile tools to work with scaled images, masks, text and graphics in multiple semi-transparent layers and channels.

Accuracy of lunar eclipse observations made by Jesuit astronomers in China.

Science.gov (United States)

Fatoohi, L. J.; Stephenson, F. R.

1996-02-01

The Jesuit astronomers observed numerous lunar eclipses at Beijing and summaries of their observations - made between 1644 and 1785 - are preserved. The various lunar eclipse measurements that the Jesuits made are compared with the results of present-day computation.

A survey of European astronomical tables in the late middle ages

CERN Document Server

Chabás, José

2012-01-01

This is a survey of the numerous astronomical tables compiled in the late Middle Ages, which represent a major intellectual enterprise. Such tables were often the best way available at the time for transmitting precise information to the reader.

Twenty-five astronomical observations that changed the world and how to make them yourself

CERN Document Server

Marett-Crosby, Michael

2013-01-01

Human history is also the record of our fascination with the sky, and to look upwards is to follow in the steps of such greats as Galileo and Newton. What they and others once saw in the heavens for the first time, amateur astronomers can discover anew using this guide to twenty-five of the greatest journeys through space.   Starting with our most visible companion the Moon, each chapter offers a step-by-step walk-through of famous astronomical observations from the history of science. Beginning with the easiest targets, sometimes even accessible with the naked eye, the challenges become progressively more difficult. Beginner astronomers and more experienced hobbyists alike can reacquaint themselves with the wonders of our fellow planets and even reach far beyond our own solar system to touch on such incredible phenomena as the birth of new stars in nebula systems and the deceptive nothingness of black holes. The would-be astronaut can spy the International Space Station in orbit with binoculars or the dooms...

Paired and Interacting Galaxies: International Astronomical Union Colloquium No. 124

Science.gov (United States)

Sulentic, Jack W. (Editor); Keel, William C. (Editor); Telesco, C. M. (Editor)

1990-01-01

The proceedings of the International Astronomical Union Colloquium No. 124, held at the University of Alabama at Tuscaloosa, on December 4 to 7, are given. The purpose of the conference was to describe the current state of theoretical and observational knowledge of interacting galaxies, with particular emphasis on galaxies in pairs.

Explanation of the anomalous secular increase of the moon orbit eccentricity by the new theory of gravitation (NTG)

Science.gov (United States)

Ziefle, Reiner Georg

2013-03-01

Present day gravitational physics experiences a huge success in obtaining better and better experimental results. In some cases, the observations do not fit with the present knowledge of established physics. Phenomena, like the increase of the Astronomical Unit by 7 m per century or the so-called anomalous secular increase of the eccentricity of the lunar orbit by about 9 × 10^-12 per year, which can neither be explained by Einstein's Theory of General Relativity, nor by the Newtonian Theory of Gravitation, can be explained by the New Theory of Gravitation

Astronomical calibration of Gauss to Matuyama sapropels in the Mediterranean and implication for the Geomagnetic Polarity Time Scale

Science.gov (United States)

Hilgen, F. J.

1991-06-01

The astronomically calibrated age of the Olduvai Subchron is established by correlating the cyclic sapropel patterns in the Vrica section and in the sections of Semaforo (Italy), Singa (Italy), Punta Piccola (Sicily), and Francocastello (Crete) to the new astronomical solutions for the precession of the equinox and eccentricity of the earth's orbit, using inferred phase relationships between the sapropel cycles and orbital cycles. The resultant ages for the Olduvai and for older boundaries are then compared with conventional, as well as other orbitally tuned ages, for these polarity transitions. It is shown that this astronomically calibrated time scale can be extended back to the Miocene/Pliocene boundary.

Testing Moral Foundation Theory: Are Specific Moral Emotions Elicited by Specific Moral Transgressions?

Science.gov (United States)

Landmann, Helen; Hess, Ursula

2018-01-01

Moral foundation theory posits that specific moral transgressions elicit specific moral emotions. To test this claim, participants (N = 195) were asked to rate their emotions in response to moral violation vignettes. We found that compassion and disgust were associated with care and purity respectively as predicted by moral foundation theory.…

The Panchasiddhhantika : The Astronomical Work of Varaha Mihira

Science.gov (United States)

Thibaut, G.; Dvivedi, Mahamahopadhyaya Sudhakara

The lamentable state of the text as appearing in the two original manuscripts (of Varah Mihira) at the disposal of the authors, was a lesser problem then the greater disadvantage under which they laboured with the absence of a commentary. Commentaries can be hardly done without in the case of any Sanskrit astronomical work; much less so, when the text, as that of the Panchasiddhantika, describes many mathematical processes more or less diverging from those commonly employed.

Tests of two convection theories for red giant and red supergiant envelopes

Science.gov (United States)

Stothers, Richard B.; Chin, Chao-Wen

1995-01-01

Two theories of stellar envelope convection are considered here in the context of red giants and red supergiants of intermediate to high mass: Boehm-Vitense's standard mixing-length theory (MLT) and Canuto & Mazzitelli's new theory incorporating the full spectrum of turbulence (FST). Both theories assume incompressible convection. Two formulations of the convective mixing length are also evaluated: l proportional to the local pressure scale height (H(sub P)) and l proportional to the distance from the upper boundary of the convection zone (z). Applications to test both theories are made by calculating stellar evolutionary sequences into the red zone (z). Applications to test both theories are made by calculating stellar evolutionary sequences into the red phase of core helium burning. Since the theoretically predicted effective temperatures for cool stars are known to be sensitive to the assigned value of the mixing length, this quantity has been individually calibrated for each evolutionary sequence. The calibration is done in a composite Hertzsprung-Russell diagram for the red giant and red supergiant members of well-observed Galactic open clusters. The MLT model requires the constant of proportionality for the convective mixing length to vary by a small but statistically significant amount with stellar mass, whereas the FST model succeeds in all cases with the mixing lenghth simply set equal to z. The structure of the deep stellar interior, however, remains very nearly unaffected by the choices of convection theory and mixing lenghth. Inside the convective envelope itself, a density inversion always occurs, but is somewhat smaller for the convectively more efficient MLT model. On physical grounds the FST model is preferable, and seems to alleviate the problem of finding the proper mixing length.

Design and control of the precise tracking bed based on complex electromechanical design theory

Science.gov (United States)

Ren, Changzhi; Liu, Zhao; Wu, Liao; Chen, Ken

2010-05-01

The precise tracking technology is wide used in astronomical instruments, satellite tracking and aeronautic test bed. However, the precise ultra low speed tracking drive system is one high integrated electromechanical system, which one complexly electromechanical design method is adopted to improve the efficiency, reliability and quality of the system during the design and manufacture circle. The precise Tracking Bed is one ultra-exact, ultra-low speed, high precision and huge inertial instrument, which some kind of mechanism and environment of the ultra low speed is different from general technology. This paper explores the design process based on complex electromechanical optimizing design theory, one non-PID with a CMAC forward feedback control method is used in the servo system of the precise tracking bed and some simulation results are discussed.

Detection and Implications of Laser-Induced Raman Scattering at Astronomical Observatories

Directory of Open Access Journals (Sweden)

Frédéric P. A. Vogt

2017-06-01

Full Text Available Laser guide stars employed at astronomical observatories provide artificial wavefront reference sources to help correct (in part the impact of atmospheric turbulence on astrophysical observations. Following the recent commissioning of the 4 Laser Guide Star Facility (4LGSF on Unit Telescope 4 (UT4 of the Very Large Telescope (VLT, we characterize the spectral signature of the uplink beams from the 22-W lasers to assess the impact of laser scattering from the 4LGSF on science observations. We use the Multi-Unit Spectroscopic Explorer (MUSE optical integral field spectrograph mounted on the Nasmyth B focus of UT4 to acquire spectra at a resolution of R≅3000 of the uplink laser beams over the wavelength range of 4750 Å–9350 Å. We report the first detection of laser-induced Raman scattering by N_{2}, O_{2}, CO_{2}, H_{2}O, and (tentatively CH_{4} molecules in the atmosphere above the astronomical observatory of Cerro Paranal. In particular, our observations reveal the characteristic spectral signature of laser photons—but 480 Å to 2210 Å redder than the original laser wavelength of 5889.959 Å—landing on the 8.2-m primary mirror of UT4 after being Raman-scattered on their way up to the sodium layer. Laser-induced Raman scattering, a phenomenon not usually discussed in the astronomical context, is not unique to the observatory of Cerro Paranal, but it is common to any astronomical telescope employing a laser guide star (LGS system. It is thus essential for any optical spectrograph coupled to a LGS system to thoroughly handle the possibility of a Raman spectral contamination via a proper baffling of the instrument and suitable calibrations procedures. These considerations are particularly applicable for the HARMONI optical spectrograph on the upcoming Extremely Large Telescope (ELT. At sites hosting multiple telescopes, laser-collision-prediction tools should also account for the presence of Raman emission from the uplink laser beam

Fundamental constants and tests of theory in Rydberg states of hydrogenlike ions.

Science.gov (United States)

Jentschura, Ulrich D; Mohr, Peter J; Tan, Joseph N; Wundt, Benedikt J

2008-04-25

A comparison of precision frequency measurements to quantum electrodynamics (QED) predictions for Rydberg states of hydrogenlike ions can yield information on values of fundamental constants and test theory. With the results of a calculation of a key QED contribution reported here, the uncertainty in the theory of the energy levels is reduced to a level where such a comparison can yield an improved value of the Rydberg constant.

Fundamental Constants and Tests of Theory in Rydberg States of Hydrogenlike Ions

International Nuclear Information System (INIS)

Jentschura, Ulrich D.; Mohr, Peter J.; Tan, Joseph N.; Wundt, Benedikt J.

2008-01-01

A comparison of precision frequency measurements to quantum electrodynamics (QED) predictions for Rydberg states of hydrogenlike ions can yield information on values of fundamental constants and test theory. With the results of a calculation of a key QED contribution reported here, the uncertainty in the theory of the energy levels is reduced to a level where such a comparison can yield an improved value of the Rydberg constant

The astronomer and the witch Johannes Kepler's fight for his mother

CERN Document Server

Rublack, Ulinka

2015-01-01

The extraordinary tale of Johannes Kepler, one of the most admired astronomers of all time, and the six long years spent defending his mother from her neighbours' accusations of witchcraft. A story which takes us to the heart of Kepler's changing world.

Astronomers' Do-It-Yourself Project Opening A New Window on the Universe

Science.gov (United States)

1999-05-01

that we can see only by observing at these longer wavelengths," Kassim said. The results of their first observations with the new VLA system have proven their point. Aiming the VLA at the supernova remnant Cassiopeia A, the shell of debris from a giant stellar explosion, they found evidence for cool gas inside the shell that has not yet been shocked by the "reverse shock" that propagates backwards through the "ejecta" towards the explosion's center "We know how old this supernova remnant is -- about 300 years -- and whether or not the reverse shock would have passed through all the ejecta yet depends on the nature of the star that exploded and the characteristics of its winds and surroundings before its death," Kassim said. "Finding unshocked gas inside this remnant, the first direct case for such material detected in the radio part of the spectrum, confirms the predictions of supernova evolution theory and thereby advances them." Other observations showed giant, radio-emitting "bubbles" in the galaxy M87 in the constellation Virgo. These objects, also seen with the VLA at the somewhat higher frequency of 330 MHz, raised questions about how old they were and how they were powered, as well as how they are linked to the even larger halo of X-ray emission generated around this galaxy. "The shape and extent of these huge, radio-emitting regions suggests that they are relatively young, expanding, and are being powered by particles shot out of the galaxy's nucleus by the gravitational energy of a supermassive black hole," said Kassim. "Comparison of the higher frequency images with our new one made at 74 MHz show exactly the correspondence we would expect if the black hole is powering these regions," he added. The researchers, together with astronomer Phillip Kronberg and his collaborators from the University of Toronto, also looked at the Coma Cluster of galaxies, some 450 million light-years distant. "There is a radio-emitting halo around this cluster, and our image made

Supporting Evidence for the Astronomically Calibrated Age of Fish Canyon Sanidine

DEFF Research Database (Denmark)

Rivera, Tiffany; Storey, Michael; Zeeden, Christian

The relative nature of the 40Ar/39Ar radio-isotopic dating technique requires that the age and error of the monitor mineral be accurately known. The most widely accepted monitor for Cenozoic geochronology is the Fish Canyon sanidine (FCs), whose recommended published ages have varied by up to 2...... tuned stratigraphic sections. The increasingly robust quality of the astronomical timescale, with precision better than 0.1% for the last 10 million years, suggests this method of intercalibration as the best way to proceed with addressing the true age of FCs. Recently, Kuiper, et al. (2008) determined...... Noblesse multi-collector noble gas mass spectrometer for the 40Ar/39Ar experiments, analyzing single crystals of FCs relative to sanidines from the astronomically dated tephra. The use of the multi-collector instrument allowed us to obtain high precision analyses with a level of precision for fully...

Radio Astronomers Lift "Fog" on Milky Way's Dark Heart: Black Hole Fits Inside Earth's Orbit

Science.gov (United States)

2004-04-01

-emitting object would fit neatly just inside the path of the Earth's orbit around the Sun, the astronomers said. The black hole itself, they calculate, is about 14 million miles across, and would fit easily inside the orbit of Mercury. Black holes are concentrations of matter so dense that not even light can escape their powerful gravity. The new VLBA observations provided astronomers their best look yet at a black hole system. "We are much closer to seeing the effects of a black hole on its environment here than anywhere else," Bower said. The Milky Way's central black hole, like its more-massive cousins in more-active galactic nuclei, is believed to be drawing in material from its surroundings, and in the process powering the emission of the radio waves. While the new VLBA observations have not provided a final answer on the nature of this process, they have helped rule out some theories, Bower said. Based on the latest work, he explained, the top remaining theories for the nature of the radio- emitting object are jets of subatomic particles, similar to those seen in radio galaxies; and some theories involving matter being accelerated near the edge of the black hole. As the astronomers studied Sagittarius A* at higher and higher radio frequencies, the apparent size of the object became smaller. This fact, too, Bower said, helped rule out some ideas of the object's nature. The decrease in observed size with increasing frequency, or shorter wavelength, also gives the astronomers a tantalizing target. "We think we can eventually observe at short enough wavelengths that we will see a cutoff when we reach the size of the black hole itself," Bower said. In addition, he said, "in future observations, we hope to see a 'shadow' cast by a gravitational lensing effect of the very strong gravity of the black hole." In 2000, Falcke and his colleagues proposed such an observation on theoretical grounds, and it now seems feasible. "Imaging the shadow of the black hole's event horizon is now

An Explanatory Item Response Theory Approach for a Computer-Based Case Simulation Test

Science.gov (United States)

Kahraman, Nilüfer

2014-01-01

Problem: Practitioners working with multiple-choice tests have long utilized Item Response Theory (IRT) models to evaluate the performance of test items for quality assurance. The use of similar applications for performance tests, however, is often encumbered due to the challenges encountered in working with complicated data sets in which local…

Classical testing particles and (4 + N)-dimensional theories of space-time

International Nuclear Information System (INIS)

Nieto-Garcia, J.A.

1986-01-01

The Lagrangian theory of a classical relativistic spinning test particle (top) developed by Hanson and Regge and by Hojman is briefly reviewed. Special attention is devoted to the constraints imposed on the dynamical variables associated with the system of this theory. The equations for a relativistic top are formulated in a way suitable for use in the study of geometrical properties of the 4 + N-dimensional Kaluza-Klein background. It is shown that the equations of motion of a top in five dimensions reduce to the Hanson-Regge generalization of the Bargmann-Michel-Telegdi equations of motion in four dimensions when suitable conditions on the spin tensor are imposed. The classical bosonic relativistic string theory is discussed and the connection of this theory with the top theory is examined. It is found that the relation between the string and the top leads naturally to the consideration of a 3-dimensional extended system (called terron) which sweeps out a 4-dimensional surface as it evolves in a space-time. By using a square root procedure based on ideas by Teitelboim a theory of a supersymmetric top is developed. The quantization of the new supersymmetric system is discussed. Conclusions and suggestions for further research are given

Brazilian Participations in the International Astronomical Search Collaboration

Science.gov (United States)

Rojas, G. A.; Dalla-Costa, L. J.; Kalmus, A. T.; Kroth, E. C.; Matos, M. F.; Silva, A. L.; Silva, G. G.

2014-10-01

International Astronomical Search Collaboration (IASC) is an international educational project between universities, schools, observatories and research institutions. Its main objective is to enroll high school and college students in the monitoring and discovery of asteroids and Near Earth Objects (NEOs), especially Potentially Hazardous Asteroids. The methodology consists in the analysis of astronomical images obtained in several observatories in North America and Hawaii. The images are distributed throughout the school network and the results must be delivered in a 72-hour timeframe. Since 2010 Brazilian universities and schools have joined IASC, resulting in over a dozen new asteroids found (3 of them NEOs), and hundreds of measurements for already known asteroids. A major event in this collaboration was the All-Brazil Asteroid Search Campaign, which was conducted in September 2012. 2013 marks the fourth year of Brazilian participations in IASC, with one important milestone: the third straight appearance of a Brazilian institution in the Pan-STARRS campaign, which uses the PS1 telescope in Haleakala, Hawaii. We will present a summary of the overall results, as well as the latest news from 2013 campaigns. We will discuss the impact promoted by the past events, such as how the interest in astronomy changed before and after the campaigns, and it has helped the students to choose their future careers.

An astronomical observatory for Peru

Science.gov (United States)

del Mar, Juan Quintanilla; Sicardy, Bruno; Giraldo, Víctor Ayma; Callo, Víctor Raúl Aguilar

2011-06-01

Peru and France are to conclude an agreement to provide Peru with an astronomical observatory equipped with a 60-cm diameter telescope. The principal aims of this project are to establish and develop research and teaching in astronomy. Since 2004, a team of researchers from Paris Observatory has been working with the University of Cusco (UNSAAC) on the educational, technical and financial aspects of implementing this venture. During an international astronomy conference in Cusco in July 2009, the foundation stone of the future Peruvian Observatory was laid at the top of Pachatusan Mountain. UNSAAC, represented by its Rector, together with the town of Oropesa and the Cusco regional authority, undertook to make the sum of 300,000€ available to the project. An agreement between Paris Observatory and UNSAAC now enables Peruvian students to study astronomy through online teaching.

Star Ware: The Amateur Astronomer's Guide to Choosing, Buying, and Using Telescopes and Accessories, 3rd Edition

Science.gov (United States)

Harrington, Philip S.

2002-05-01

Praise for the Second Edition of Star Ware "Star Ware is still a tour de force that any experienced amateur will find invaluable, and which hardware-minded beginners will thoroughly enjoy." -Robert Burnham, Sky & Telescope magazine "Star Ware condenses between two covers what would normally take a telescope buyer many months to accumulate." -John Shibley, Astronomy magazine Now more than ever, the backyard astronomer has a dazzling array of choices when it comes to telescope shopping-which can make choosing just the right sky-watching equipment a formidable challenge. In this revised and updated edition of Star Ware, the essential guide to buying astronomical equipment, award-winning astronomy writer Philip Harrington does the work for you, analyzing and exploring today's astronomy market and offering point-by-point comparisons of everything you need. Whether you're an experienced amateur astronomer or just getting started, Star Ware, Third Edition will prepare you to explore the farthest reaches of space with: Extensive, expanded reviews of leading models and accessories, including dozens of new products, to help you buy smart A clear, step-by-step guide to all aspects of purchasing everything from telescopes and binoculars to filters, mounts, lenses, cameras, film, star charts, guides and references, and much more Eleven new do-it-yourself projects for making unique astronomical equipment at home Easy tips on maintenance, photography, and star-mapping to help you get the most out of your telescope Lists of where to find everything astronomical, including Internet sites and Web resources; distributors, dealers, and conventions; and corporate listings for products and services

Optimizing hydroxyl airglow retrievals from long-slit astronomical spectroscopic observations

Directory of Open Access Journals (Sweden)

C. Franzen

2017-08-01

Full Text Available Astronomical spectroscopic observations from ground-based telescopes contain background emission lines from the terrestrial atmosphere's airglow. In the near infrared, this background is composed mainly of emission from Meinel bands of hydroxyl (OH, which is produced in highly excited vibrational states by reduction of ozone near 90 km. This emission contains a wealth of information on the chemical and dynamical state of the Earth's atmosphere. However, observation strategies and data reduction processes are usually optimized to minimize the influence of these features on the astronomical spectrum. Here we discuss a measurement technique to optimize the extraction of the OH airglow signal itself from routine J-, H-, and K-band long-slit astronomical spectroscopic observations. As an example, we use data recorded from a point-source observation by the Nordic Optical Telescope's intermediate-resolution spectrograph, which has a spatial resolution of approximately 100 m at the airglow layer. Emission spectra from the OH vibrational manifold from v′  =  9 down to v′  =  3, with signal-to-noise ratios up to 280, have been extracted from 10.8 s integrations. Rotational temperatures representative of the background atmospheric temperature near 90 km, the mesosphere and lower thermosphere region, can be fitted to the OH rotational lines with an accuracy of around 0.7 K. Using this measurement and analysis technique, we derive a rotational temperature distribution with v′ that agrees with atmospheric model conditions and the preponderance of previous work. We discuss the derived rotational temperatures from the different vibrational bands and highlight the potential for both the archived and future observations, which are at unprecedented spatial and temporal resolutions, to contribute toward the resolution of long-standing problems in atmospheric physics.

Factors Contributing to Lifelong Science Learning: Amateur Astronomers and Birders

Science.gov (United States)

Jones, M. Gail; Corin, Elysa Nicole; Andre, Thomas; Childers, Gina M.; Stevens, Vanessa

2017-01-01

This research examined lifelong science learning reported by amateur astronomers and birders. One hundred seven adults who reported engaging in an informal (out-of-school) science interest were interviewed as part of an ongoing series of studies of lifelong science learners. The goal of the study was to gain insight into how and why amateur…

Astronomers Discover Fastest-Spinning Pulsar

Science.gov (United States)

2006-01-01

Astronomers using the National Science Foundation's Robert C. Byrd Green Bank Telescope have discovered the fastest-spinning neutron star ever found, a 20-mile-diameter superdense pulsar whirling faster than the blades of a kitchen blender. Their work yields important new information about the nature of one of the most exotic forms of matter known in the Universe. Pulsar Graphic Pulsars Are Spinning Neutron Stars CREDIT: Bill Saxton, NRAO/AUI/NSF (Click on image for larger version) "We believe that the matter in neutron stars is denser than an atomic nucleus, but it is unclear by how much. Our observations of such a rapidly rotating star set a hard upper limit on its size, and hence on how dense the star can be.," said Jason Hessels, a graduate student at McGill University in Montreal. Hessels and his colleagues presented their findings to the American Astronomical Society's meeting in Washington, DC. Pulsars are spinning neutron stars that sling "lighthouse beams" of radio waves or light around as they spin. A neutron star is what is left after a massive star explodes at the end of its "normal" life. With no nuclear fuel left to produce energy to offset the stellar remnant's weight, its material is compressed to extreme densities. The pressure squeezes together most of its protons and electrons to form neutrons; hence, the name "neutron star." "Neutron stars are incredible laboratories for learning about the physics of the fundamental particles of nature, and this pulsar has given us an important new limit," explained Scott Ransom, an astronomer at the National Radio Astronomy Observatory and one of Hessels' collaborators on this work. The scientists discovered the pulsar, named PSR J1748-2446ad, in a globular cluster of stars called Terzan 5, located some 28,000 light-years from Earth in the constellation Sagittarius. The newly-discovered pulsar is spinning 716 times per second, or at 716 Hertz (Hz), readily beating the previous record of 642 Hz from a pulsar

Evaluation of Northwest University, Kano Post-UTME Test Items Using Item Response Theory

Science.gov (United States)

Bichi, Ado Abdu; Hafiz, Hadiza; Bello, Samira Abdullahi

2016-01-01

High-stakes testing is used for the purposes of providing results that have important consequences. Validity is the cornerstone upon which all measurement systems are built. This study applied the Item Response Theory principles to analyse Northwest University Kano Post-UTME Economics test items. The developed fifty (50) economics test items was…

Linear feature detection algorithm for astronomical surveys - I. Algorithm description

Science.gov (United States)

Bektešević, Dino; Vinković, Dejan

2017-11-01

Computer vision algorithms are powerful tools in astronomical image analyses, especially when automation of object detection and extraction is required. Modern object detection algorithms in astronomy are oriented towards detection of stars and galaxies, ignoring completely the detection of existing linear features. With the emergence of wide-field sky surveys, linear features attract scientific interest as possible trails of fast flybys of near-Earth asteroids and meteors. In this work, we describe a new linear feature detection algorithm designed specifically for implementation in big data astronomy. The algorithm combines a series of algorithmic steps that first remove other objects (stars and galaxies) from the image and then enhance the line to enable more efficient line detection with the Hough algorithm. The rate of false positives is greatly reduced thanks to a step that replaces possible line segments with rectangles and then compares lines fitted to the rectangles with the lines obtained directly from the image. The speed of the algorithm and its applicability in astronomical surveys are also discussed.

Astro-imaging projects for amateur astronomers a maker’s guide

CERN Document Server

Chung, Jim

2015-01-01

This is the must-have guide for all amateur astronomers who double as makers, doers, tinkerers, problem-solvers, and inventors. In a world where an amateur astronomy habit can easily run into the many thousands of dollars, it is still possible for practitioners to get high-quality results and equipment on a budget by utilizing DIY techniques. Surprisingly, it's not that hard to modify existing equipment to get new and improved usability from older or outdated technology, creating an end result that can outshine the pricey higher-end tools. All it takes is some elbow grease, a creative and open mind and the help of Chung's hard-won knowledge on building and modifying telescopes and cameras. With this book, it is possible for readers to improve their craft, making their equipment more user friendly. The tools are at hand, and the advice on how to do it is here. Readers will discover a comprehensive presentation of astronomical projects that any amateur on any budget can replicate – projects that utilize lead...

Orbiting Water Molecules Dance to Tune Of Galaxy's "Central Engine," Astronomers Say

Science.gov (United States)

2000-01-01

A disk of water molecules orbiting a supermassive black hole at the core of a galaxy 60 million light-years away is "reverberating" in response to variations in the energy output from the galaxy's powerful "central engine" close to the black hole, astronomers say. The team of astronomers used the National Science Foundation's (NSF) Very Large Array (VLA) radio telescope in New Mexico and the 100-meter-diameter radio telescope of the Max Planck Institute for Radio Astronomy at Effelsberg, Germany, to observe the galaxy NGC 1068 in the constellation Cetus. They announced their findings today at the American Astronomical Society's meeting in Atlanta. The water molecules, in a disk some 5 light-years in diameter, are acting as a set of giant cosmic radio-wave amplifiers, called masers. Using energy radiated by the galaxy's "central engine," the molecules strengthen, or brighten, radio emission at a particular frequency as seen from Earth. "We have seen variations in the radio 'brightness' of these cosmic amplifiers that we believe were caused by variations in the energy output of the central engine," said Jack Gallimore, an astronomer at the National Radio Astronomy Observatory (NRAO) in Charlottesville, VA. "This could provide us with a valuable new tool for learning about the central engine itself," he added. Gallimore worked with Stefi Baum of the Space Telescope Science Institute in Baltimore, MD; Christian Henkel of the Max Planck Institute for Radio Astronomy in Bonn, Germany; Ian Glass of the South African Astronomical Observatory; Mark Claussen of the NRAO in Socorro, NM; and Almudena Prieto of the European Southern Observatory in Munich, Germany. "Our observations show that NGC 1068 is the second-known case of a giant disk of water molecules orbiting a supermassive black hole at a galaxy's core," Gallimore said. The first case was the galaxy NGC 4258 (Messier 106), whose disk of radio-amplifying water molecules was measured by the NSF's Very Long Baseline

Einstein's Jury: The Race to Test Relativity

International Nuclear Information System (INIS)

Ehlers, Juergen

2007-01-01

'I know very well that my theory rests on a shaky foundation. What attracts me to it is that it leads to consequences that seem to be accessible to experiment, and it provides a starting point for the theoretical understanding of gravitation', wrote Einstein in 1911. Einstein's Jury by Jeffrey Crelinsten-well documented, well written, and fascinating to read-describes how, from 1909 on, Einstein's two theories of relativity became known to astronomers, and how the predictions made between 1907 and 1915 were received as challenges to observers. The author gives a non-technical account of the efforts made until 1930 to test these predictions; he focuses on two of the three classical tests, namely gravitational redshift and bending of light; the 'jury' consists mainly of American observers-Adams, Campbell, Curtis, Hale, Perrin, St John, Trumpler and others-working with newly built large telescopes, and the Britons Eddington and Evershed. The major steps which, after a long struggle, convinced the majority of astronomers that Einstein was right, are narrated chronologically in rather great detail, especially the work at Lick Observatory, before and after the famous British observation of 1919, on solar eclipses, and the work at Mount Wilson and the Indian Kodaikanal Observatories to extract the gravitational redshift from the complicated spectrum of the sun. The account of the eclipse work which was carried out between 1918 and 1923 by Lick astronomers corrects the impression suggested by many historical accounts that the British expedition alone settled the light-bending question. Apart from these main topics, the anomalous perihelion advance of Mercury and the ether problem are covered. By concentrating on astronomy rather than on physics this book complements the rich but repetitive literature on Einstein and relativity which appeared in connection with the commemoration of Einstein's annus mirabilis, 2005. The well told stories include curiosities such as the

Recent experiments testing an opponent-process theory of acquired motivation.

Science.gov (United States)

Solomon, R L

1980-01-01

There are acquired motives of the addiction type which seem to be non-associative in nature. They all seem to involve affective phenomena caused by reinforcers, unconditioned stimuli or innate releasers. When such stimuli are repeatedly presented, at least three affective phenomena occur: (1) affective contrast effects, (2) affective habituation (tolerance), and (3) affective withdrawal syndromes. These phenomena can be precipitated either by pleasant or unpleasant events (positive or negative reinforcers). Whenever we see these three phenomena, we also see the development of an addictive cycle, a new motivational system. These phenomena are explained by an opponent-process theory of motivation which holds that there are affect control systems which oppose large departures from affective equilibrium. The control systems are strengthened by use and weakened by disuse. Current observations and experiments testing the theory are described for: (1) the growth of social attachment (imprinting) in ducklings; and (2) the growth of adjunctive behaviors. The findings so far support the theory.

Algorithms for classification of astronomical object spectra

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Wasiewicz, P.; Szuppe, J.; Hryniewicz, K.

2015-09-01

Obtaining interesting celestial objects from tens of thousands or even millions of recorded optical-ultraviolet spectra depends not only on the data quality but also on the accuracy of spectra decomposition. Additionally rapidly growing data volumes demands higher computing power and/or more efficient algorithms implementations. In this paper we speed up the process of substracting iron transitions and fitting Gaussian functions to emission peaks utilising C++ and OpenCL methods together with the NOSQL database. In this paper we implemented typical astronomical methods of detecting peaks in comparison to our previous hybrid methods implemented with CUDA.

What Astronomers and the AAS Need to be Doing to Curb Light Pollution

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Green, D. W. E.

2001-12-01

Astronomers and especially the AAS are doing apalling little in the war on light pollution. This is quite surprising, considering that optical groundbased astronomy may become nearly extinct in the 21st century if we don't get more serious about the loss of our night skies to artificial lighting. Part of the blame must be placed on astronomers throughout the 20th century (particularly before 1980), as very few of them seem to have set an example by starting an early crusade against bad outdoor night lighting (save for a handful of important individuals near large U.S. observatories, and a few connected with smaller observatories); this apathy of earlier generations of astronomers fueled the current general apathy within the AAS and aided the opening of the floodgates in terms of the disastrous lighting situation now upon us in terms of drowning out the night sky. There are possible solutions, and they need to be discussed and acted upon quickly. For example, the AAS should require that all members include a useful amount (say, \\$30) in annual membership fees to be directly transmitted to the International Dark Sky Association, and the AAS should make constant visible strides to educate the public and government officials of the absolute need to reduce outdoor lighting levels and to fully shield all outdoor lighting. There are many other areas of research into outdoor lighting that the AAS should fund or officially/strongly support, so that the astronomical community can better be educated (and can better educate the public) on the evils of bad and thoughtless outdoor-lighting practices; such research includes developing a comprehensive database of national statistics on numbers and types of different outdoor lamps, as a function of time (thus, historical), and also a comprehensive database including all local, state, and federal lighting laws and ordinances together with legal court cases (and their outcomes) involving outdoor night lighting. And professional

Help-Seeking Decisions of Battered Women: A Test of Learned Helplessness and Two Stress Theories.

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Wauchope, Barbara A.

This study tested the learned helplessness theory, stress theory, and a modified stress theory to determine the best model for predicting the probability that a woman would seek help when she experienced severe violence from a male partner. The probability was hypothesized to increase as the stress of the violence experienced increased. Data were…

SIRU utilization. Volume 1: Theory, development and test evaluation

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Musoff, H.

1974-01-01

The theory, development, and test evaluations of the Strapdown Inertial Reference Unit (SIRU) are discussed. The statistical failure detection and isolation, single position calibration, and self alignment techniques are emphasized. Circuit diagrams of the system components are provided. Mathematical models are developed to show the performance characteristics of the subsystems. Specific areas of the utilization program are identified as: (1) error source propagation characteristics and (2) local level navigation performance demonstrations.

Karl Julius Lohnert - an unknown astronomer, experimental psychologist and teacher (German Title: Karl Julius Lohnert - ein unbekannter Astronom, experimenteller Psychologe und Lehrer)

Science.gov (United States)

Schmadel, Lutz D.; Guski-Leinwand, Susanne

2011-08-01

Karl Julius Lohnert (1885-1944) with his double biography as astronomer and psychologist is hardly known in both fields. As a student of astronomy in Heidelberg, Lohnert discovered a couple of minor planets and he dedicated one to his PhD supervisor, the famous Leipzig professor for philosophy, Wilhelm Wundt. This connection is discussed for the first time almost one century after the naming of (635) Vundtia. The paper elucidates some biographical stations of Lohnert.

General theory of light propagation and imaging through the atmosphere

CERN Document Server

McKechnie, T Stewart

2016-01-01

This book lays out a new, general theory of light propagation and imaging through Earth’s turbulent atmosphere. Current theory is based on the – now widely doubted – assumption of Kolmogorov turbulence. The new theory is based on a generalized atmosphere, the turbulence characteristics of which can be established, as needed, from readily measurable properties of point-object, or star, images. The pessimistic resolution predictions of Kolmogorov theory led to lax optical tolerance prescriptions for large ground-based astronomical telescopes which were widely adhered to in the 1970s and 1980s. Around 1990, however, it became clear that much better resolution was actually possible, and Kolmogorov tolerance prescriptions were promptly abandoned. Most large telescopes built before 1990 have had their optics upgraded (e.g., the UKIRT instrument) and now achieve, without adaptive optics (AO), almost an order of magnitude better resolution than before. As well as providing a more comprehensive and precise under...

Astronomy for Astronomical Numbers: A Worldwide Massive Open Online Class

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Impey, Chris D.; Wenger, Matthew C.; Austin, Carmen L.

2015-01-01

Astronomy: State of the Art is a massive, open, online class (MOOC) offered through Udemy by an instructional team at the University of Arizona. With nearly 24,000 enrolled as of early 2015, it is the largest astronomy MOOC available. The astronomical numbers enrolled do not translate into a similar level of engagement. The content consists of 14…

Astronomical cycle origin of bedded chert: A middle Triassic bedded chert sequence, Inuyama, Japan

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Ikeda, Masayuki; Tada, Ryuji; Sakuma, Hironobu

2010-09-01

Astronomical forcing is one of the main drivers of climate change, and astronomical cyclicity recorded in sediments provides a clue to understand the dynamics of the global climate system. Bedded cherts consist of rhythmic alternations of chert and shale beds. Although previous studies have hypothesized that the origin of bedded chert is related to astronomical cycles (e.g. Fischer, 1976; Hori et al., 1993), conclusive proof remains elusive. To explore this possibility, we established a continuous, high-resolution lithostratigraphy of middle Triassic bedded chert in Central Japan. The average duration of each chert-shale couplet is 20 kyr, similar to that of the precession cycle. Spectral analysis of a bed number series of thickness variations in chert beds was performed assuming that each chert-shale couplet represents a 20-kyr precession cycle. The results reveal cycles involving approximately 200, 20, 5, and 2-3 beds, corresponding to periodicities of approximately 4000, 400, 100, and 40-60 kyr, respectively. By further assuming that the 20-bed cycle represents a 405-kyr eccentricity cycle of constant and stable periodicity, we converted the bed number series to a time series. Spectral analysis of the time series revealed distinct periodicities of 3600, 117, 97, and 38 kyr, in addition to 405 kyr. Besides 3600 kyr, these periodicities agree well with the 120, 95, and 37 kyr periodicities for eccentricity cycles and the obliquity cycle during the Triassic. Moreover, we detected amplitude modulation of the approximately 100-kyr cycle of thickness variations in chert beds with a 405-kyr periodicity, which may correspond to amplitude modulation of 100-kyr climatic precession cycle with the 405-kyr periodicity. The approximately 3600-kyr periodicity described above and 1800-kyr periodicity manifested as the amplitude modulation of the 405-kyr cycle are correlated to present-day long-term eccentricity cycles of 2400 and 4800 kyr evolved by chaotic behavior of solar

Overview of Classical Test Theory and Item Response Theory for Quantitative Assessment of Items in Developing Patient-Reported Outcome Measures

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Cappelleri, Joseph C.; Lundy, J. Jason; Hays, Ron D.

2014-01-01

Introduction The U.S. Food and Drug Administration’s patient-reported outcome (PRO) guidance document defines content validity as “the extent to which the instrument measures the concept of interest” (FDA, 2009, p. 12). “Construct validity is now generally viewed as a unifying form of validity for psychological measurements, subsuming both content and criterion validity” (Strauss & Smith, 2009, p. 7). Hence both qualitative and quantitative information are essential in evaluating the validity of measures. Methods We review classical test theory and item response theory approaches to evaluating PRO measures including frequency of responses to each category of the items in a multi-item scale, the distribution of scale scores, floor and ceiling effects, the relationship between item response options and the total score, and the extent to which hypothesized “difficulty” (severity) order of items is represented by observed responses. Conclusion Classical test theory and item response theory can be useful in providing a quantitative assessment of items and scales during the content validity phase of patient-reported outcome measures. Depending on the particular type of measure and the specific circumstances, either one or both approaches should be considered to help maximize the content validity of PRO measures. PMID:24811753

Visualization of Astronomical Nebulae via Distributed Multi-GPU Compressed Sensing Tomography.

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Wenger, S; Ament, M; Guthe, S; Lorenz, D; Tillmann, A; Weiskopf, D; Magnor, M

2012-12-01

The 3D visualization of astronomical nebulae is a challenging problem since only a single 2D projection is observable from our fixed vantage point on Earth. We attempt to generate plausible and realistic looking volumetric visualizations via a tomographic approach that exploits the spherical or axial symmetry prevalent in some relevant types of nebulae. Different types of symmetry can be implemented by using different randomized distributions of virtual cameras. Our approach is based on an iterative compressed sensing reconstruction algorithm that we extend with support for position-dependent volumetric regularization and linear equality constraints. We present a distributed multi-GPU implementation that is capable of reconstructing high-resolution datasets from arbitrary projections. Its robustness and scalability are demonstrated for astronomical imagery from the Hubble Space Telescope. The resulting volumetric data is visualized using direct volume rendering. Compared to previous approaches, our method preserves a much higher amount of detail and visual variety in the 3D visualization, especially for objects with only approximate symmetry.

Astronomical calibration of the middle Eocene Contessa Highway section (Gubbio, Italy)

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Jovane, Luigi; Sprovieri, Mario; Coccioni, Rodolfo; Florindo, Fabio; Marsili, Andrea; Laskar, Jacques

2010-09-01

The Eocene climatic system experienced an important transition from warm Paleocene greenhouse to icehouse Oligocene conditions. This transition could first appear as a long-term cooling trend but, at an up-close look, this period is a complex combination of climatic events and, for most of them, causes and consequences are still not fully characterized. In this context, a study has been carried out on the middle Eocene sedimentary succession of the Contessa Highway section, central Italy, which is proposed as the Global Stratotype Section and Point (GSSP) for the Lutetian/Bartonian boundary at the top of the Chron 19n, with an astronomically calibrated age of 41.23 Ma. Through a cyclostratigraphic analysis of the rhythmic sedimentary alternations and combination with the results of time series analysis of the proxy record, we provide an orbital tuning of the middle Eocene and astronomical calibration of the bio-magnetostratigraphic events (particularly for the C19n/C18r Chron boundary) recognized at the Contessa Highway section.

Property and instrumental heritage of the Bordeaux Astronomical Observatory; What future?

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de La Noë, J.; Charlot, P.; Grousset, F.

2009-11-01

In the years 1870, the Government of the Third Republic decided to develop scientific and technical research. Such an effort contributed to supporting and creating universities and other institutes such as astronomical observatories. The dual wish of the Bordeaux council and professors at the Faculté des Sciences de Bordeaux led to the foundation of the astronomical Observatory of Bordeaux. It was set up by Georges Rayet in the years 1880's. The observatory owns a property of 12 hectares with a dozen of buildings, five domes housing an instrument, a Würzburg radiotelescope, a 2.5 meter radiotelescope, and a large collection of about 250 instruments, 4 500 photographic plates, drawings, slides for teaching astronomy, maps of the Carte du Ciel and 200 files of archives. In addition, the library contains about a thousand books for the period 1600-1950. The future of the observatory is not clear at the present time, when the Laboratoire d'Astrophysique will leave to the campus in a few years.

Testing gravity with EG: mapping theory onto observations

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Leonard, C. Danielle; Ferreira, Pedro G.; Heymans, Catherine

2015-12-01

We present a complete derivation of the observationally motivated definition of the modified gravity statistic EG. Using this expression, we investigate how variations to theory and survey parameters may introduce uncertainty in the general relativistic prediction of EG. We forecast errors on EG for measurements using two combinations of upcoming surveys, and find that theoretical uncertainties may dominate for a futuristic measurement. Finally, we compute predictions of EG under modifications to general relativity in the quasistatic regime, and comment on the pros and cons of using EG to test gravity with future surveys.

An empirical comparison of Item Response Theory and Classical Test Theory

Directory of Open Access Journals (Sweden)

Špela Progar

2008-11-01

Full Text Available Based on nonlinear models between the measured latent variable and the item response, item response theory (IRT enables independent estimation of item and person parameters and local estimation of measurement error. These properties of IRT are also the main theoretical advantages of IRT over classical test theory (CTT. Empirical evidence, however, often failed to discover consistent differences between IRT and CTT parameters and between invariance measures of CTT and IRT parameter estimates. In this empirical study a real data set from the Third International Mathematics and Science Study (TIMSS 1995 was used to address the following questions: (1 How comparable are CTT and IRT based item and person parameters? (2 How invariant are CTT and IRT based item parameters across different participant groups? (3 How invariant are CTT and IRT based item and person parameters across different item sets? The findings indicate that the CTT and the IRT item/person parameters are very comparable, that the CTT and the IRT item parameters show similar invariance property when estimated across different groups of participants, that the IRT person parameters are more invariant across different item sets, and that the CTT item parameters are at least as much invariant in different item sets as the IRT item parameters. The results furthermore demonstrate that, with regards to the invariance property, IRT item/person parameters are in general empirically superior to CTT parameters, but only if the appropriate IRT model is used for modelling the data.