These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

Radio Astronomy Radio astronomy  

E-print Network

Effelsberg 100m telescope (Germany) Green Bank 100m telescope (National Radio Astronomy ObservatoryExperiment -10m (Chile, Europe) #12;Submillimeter radio astronomy #12;Size of telescope Snow sweep at Nobeyama 45;#12;Arecibo 300m telescope #12;Radio interferometer #12;Radio interferometer Very Large Array (VLA) (New

Metchev, Stanimir

2

Radio Astronomy  

NSDL National Science Digital Library

This article is a Why Files short piece on how astronomers use information from radio astronomy. Contrary to popular belief, large radio telescopes are not looking for signs of life outside our solar system, but are making images of black holes, centers of galaxies, and gamma ray bursts. These phenomena cannot be seen in visible light, but emit radio waves which can be translated into images. The article discusses how this process works, and the information gathered from radio waves.

Tenenbaum, David

3

Torun Radio Astronomy Observatory  

NASA Astrophysics Data System (ADS)

Torun Center for Astronomy is located at Piwnice, 15 km north of Torun, Poland. A part of the Faculty of Physics and Astronomy of the Nicolaus Copernicus University, it was created by the union of Torun Radio Astronomy Observatory (TRAO) and the Institute of Astronomy on 1 January 1997....

Murdin, P.

2000-11-01

4

CRAF Handbook for Radio Astronomy  

E-print Network

CRAF Handbook for Radio Astronomy EUROPEAN SCIENCE FOUNDATION Committee on Radio Astronomy forum for science. The ESF Expert Committee on Radio Astronomy Frequencies, CRAF, was established Astronomy Service and other passive applications. Cover: The 76-m diameter Lovell Telescope at Jodrell Bank

Rodriguez, Luis F.

5

Radio astronomy receivers  

Microsoft Academic Search

A general survey of the principles of radio astronomy receivers is presented. System noise temperature, the sensitivity of different receiver types, and the calibration of receivers are studied. A total-power receiver is analyzed as a basic radio telescope receiver and the results are used to obtain the performance of other receiver types such as the Dicke receiver, Graham's receiver, correlation

M. Tiuri

1964-01-01

6

Hartebeesthoek Radio Astronomy Observatory  

NASA Astrophysics Data System (ADS)

The Hartebeesthoek Radio Astronomy Observatory (HartRAO) is located in the Gauteng Province of South Africa, 60 km NW of Johannesburg. It is one of four national research facilities operated by the National Research Foundation. The Observatory was established in 1975 at the former NASA Deep Space Station 51, which was founded in 1961 to support unmanned US space probes to the Moon and planets, a...

Murdin, P.

2000-11-01

7

The Radio JOVE Project - Shoestring Radio Astronomy  

NASA Technical Reports Server (NTRS)

Radio JOVE is an education and outreach project intended to give students and other interested individuals hands-on experience in learning radio astronomy. They can do this through building a radio telescope from a relatively inexpensive kit that includes the parts for a receiver and an antenna as well as software for a computer chart recorder emulator (Radio Skypipe) and other reference materials

Thieman, J.; Flagg, R.; Greenman, W.; Higgins, C.; Reyes, F.; Sky, J.

2010-01-01

8

Radio Astronomy Fundamentals I John Simonetti  

E-print Network

Radio Astronomy Fundamentals I John Simonetti Spring 2012 Radio astronomy provides a very different view of the universe than optical astronomy. Radio astronomers and optical astronomers use astronomy. Radio astronomers talk about sources of radio emission. Cas A is a strong source, for example

Ellingson, Steven W.

9

Physics 343 Observational Radio Astronomy  

E-print Network

Physics 343 Observational Radio Astronomy course number = 01:750:343 web page = http will be on reserve in SERC, and an online "Essential Radio Astronomy" course taught at the University of Virginia, or programs that you write yourself. #12; Course meetings Lectures: Serin 401, once a week, M 10

Baker, Andrew J.

10

Physics 343 Observational Radio Astronomy  

E-print Network

Physics 343 Observational Radio Astronomy course number = 01:750:343 web page = http Radio Astronomy" course taught at the University of Virginia is linked from our main web page. Pre do numbercrunching with Excel or programs that you write. #12; Course meetings Lectures: Serin

Baker, Andrew J.

11

Synthesis imaging in radio astronomy  

Microsoft Academic Search

Recent advances in techniques and instrumentation for radio synthesis imaging in astronomy are discussed in a collection of review essays. Topics addressed include coherence in radio astronomy, the interferometer in practice, primary antenna elements, cross correlators, calibration and editing, sensitivity, deconvolution, self-calibration, error recognition, and image analysis. Consideration is given to wide-field imaging (bandwidth and time-average smearing, noncoplanar arrays, and

Richard A. Perley; Frederic R. Schwab; Alan H. Bridle

1989-01-01

12

National Radio Astronomy Observatory Dark Energy  

E-print Network

National Radio Astronomy Observatory Dark Energy: Constraints from Astronomy, Answers from Physics? Jim Condon #12;National Radio Astronomy Observatory UVa/NRAO DE Lunch Talk 2005 Nov. 30 Constraining expected for a quantum vacuum (Weinberg 1989, Rev Mod Phys, 61, 1) #12;National Radio Astronomy Observatory

Groppi, Christopher

13

An Introduction to Radio Astronomy  

NASA Astrophysics Data System (ADS)

Preface; 1. Introduction; 2. The nature of the radio signal; 3. Signals, noise, radiometers and spectrometers; 4. Single-aperture radio telescopes; 5. The two-element interferometer; 6. Aperture synthesis; 7. Radiation, propagation and absorption of radio waves; 8. The local universe; 9. The interstellar medium; 10. Galactic dynamics; 11. Stars; 12. Pulsars; 13. Radio galaxies and quasars; 14. Cosmology fundamentals; 15. The angular structure of the CMB; 16. Cosmology: discrete radio sources and gravitational lensing; 17. The future of radio astronomy; Appendixes; References; Index.

Burke, Bernard F.; Graham-Smith, Francis

2014-02-01

14

Radio Frequency Interference and the National Radio Astronomy Observatory  

NASA Astrophysics Data System (ADS)

Radio frequency interference (RFI) and radio astronomy have been closely linked since the emergence of radio astronomy as a scientific discipline in the 1930s. Even before the official establishment of the National Radio Astronomy Observatory, protection against contemporary and future radio noise levels was seen as crucial to ensure success of any new observatory. My talk will examine the various local, regional, national, and international efforts enacted to protect NRAO and other American radio astronomy sites from RFI.

Smith, Sierra

2014-01-01

15

The future for radio astronomy  

NASA Astrophysics Data System (ADS)

THE TRANSIENT UNIVERSE Rene P Breton and Tom Hassall argue that, while radio astronomy has always involved transient phenomena, exploration of this part of the electromagnetic spectrum has been falling behind because of the lack of data. But the advent of a new generation of radio telescopes such as LOFAR, could change that.

Breton, Rene P.; Hassall, Tom

2013-12-01

16

National Radio Astronomy Observatory Electronics Division Technical Note No. 219  

E-print Network

1 National Radio Astronomy Observatory Electronics Division Technical Note No. 219 Measurements of Automotive Radar Emissions received by a Radio Astronomy Observatory Darrel Emerson (National Radio Astronomy upon radio astronomy observations, measurements sponsored by the National Science Foundation were

Groppi, Christopher

17

National Radio Astronomy Observatory The radio emission (orange) detected  

E-print Network

NRAO National Radio Astronomy Observatory #12;The radio emission (orange) detected by the NRAO Very located in New Mexico. The National Radio Astronomy Observatory (NRAO) enables cutting-edge research in the study of the Universe using radio astronomy techniques, attracts and trains future scientists

Groppi, Christopher

18

(Astro)Physics 343 Observational Radio Astronomy  

E-print Network

. Last year: "Current and Future Radio Astronomy Projects" This year: the search for extraterrestrial intelligence? the New Jersey roots of radio astronomy? why the Iridium telecommunications satellites are evil

Baker, Andrew J.

19

Planetary radio astronomy from Voyager  

NASA Technical Reports Server (NTRS)

The technique of radio astronomy makes it possible for a remote observer to detect the presence of magnetic fields and plasmas in planetary environments. Prior to the flights of the Voyager spacecraft, radio astronomical studies of Jupiter from earth and from earth orbit had correctly predicted the strength and orientation of Jupiter's magnetic field and trapped radiation belts. The Voyager Planetary Radio Astronomy investigations have now provided measurements of the complete spectrum of low frequency radio emissions from both planets. Each Voyager instrument consists of a pair of orthogonal, 10-m, electric monopole antennas which are connected to a step-tuned, superheterodyne receiver operating over the frequency range from 1.2 kHz to 40.5 MHz. The Voyager trajectory provided observations from above both the sunlit and nightside hemispheres of Jupiter. Saturn's nonthermal radio emission has been observed at frequencies as low as 3 kHz and as high as 1.2 MHz.

Alexander, J. K.

1983-01-01

20

National Radio Astronomy Observatory Dark Energy  

E-print Network

National Radio Astronomy Observatory Dark Energy: Constraints from the Hubble Constant Jim Condon, 43, 625 #12;National Radio Astronomy Observatory UVa/NRAO DE Lunch Talk 2006 Jan. 25 What.086·1019 km H0 1.36 · 1010 years #12;National Radio Astronomy Observatory UVa/NRAO DE Lunch Talk 2006 Jan. 25

Groppi, Christopher

21

National Radio Astronomy Observatory Associated Universities, Inc.  

E-print Network

National Radio Astronomy Observatory Associated Universities, Inc. OUTSIDE OBSERVER TRAVEL: ________________________________________ Travel office East: Travel office West: Fiscal Office Fiscal Office National Radio Astronomy Observatory National Radio Astronomy Observatory P.O. Box 2 P.O. Box O 1 Green Bank, WV 24944-0002 Socorro, NM 87801

Groppi, Christopher

22

Weather Forecasting for Radio Astronomy  

E-print Network

Weather Forecasting for Radio Astronomy Part I: The Mechanics and Physics Ronald J Maddalena August 1, 2008 #12;Outline Part I Background -- research inspirations and aspirations Vertical weather, .... Part II Results on refraction & air mass (with Jeff Paradis) Part III Results on opacity, weather

Groppi, Christopher

23

Interference problems in radio astronomy  

NASA Astrophysics Data System (ADS)

The problem of vulnerability of radio astronomy as a passive service where no signal is transmitted by man are discussed; since a passive service cannot interfere with an active service, the conflict is due to active usage of bands allocated to passive services. The problem is divided into global, regional, and local problems, indicating the scale on which they have an impact on radio astronomy. It is noted that on a local scale as well as on regional and global scales, there is a pressure to allocate additional frequencies to new forms of TV and other types of services. Active solutions investigated at a number of radio observatories are presented, including frequency monitoring, receiver modifications, and software methods for cleaning the data from interfering signals.

Spoelstra, T. A. Th.

24

47 CFR 2.107 - Radio astronomy station notification.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Radio astronomy station notification. 2.107 Section...Radio Frequencies 2.107 Radio astronomy station notification. (a) Pursuant...Geneva, 1982), operators of radio astronomy stations desiring international...

2013-10-01

25

47 CFR 2.107 - Radio astronomy station notification.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Radio astronomy station notification. 2.107 Section...Radio Frequencies 2.107 Radio astronomy station notification. (a) Pursuant...Geneva, 1982), operators of radio astronomy stations desiring international...

2014-10-01

26

47 CFR 2.107 - Radio astronomy station notification.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Radio astronomy station notification. 2.107 Section...Radio Frequencies 2.107 Radio astronomy station notification. (a) Pursuant...Geneva, 1982), operators of radio astronomy stations desiring international...

2011-10-01

27

47 CFR 2.107 - Radio astronomy station notification.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Radio astronomy station notification. 2.107 Section...Radio Frequencies 2.107 Radio astronomy station notification. (a) Pursuant...Geneva, 1982), operators of radio astronomy stations desiring international...

2012-10-01

28

47 CFR 2.107 - Radio astronomy station notification.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Radio astronomy station notification. 2.107 Section...Radio Frequencies 2.107 Radio astronomy station notification. (a) Pursuant...Geneva, 1982), operators of radio astronomy stations desiring international...

2010-10-01

29

Radio Frequency Interference: Radio Astronomy's Biggest Enemy  

NASA Astrophysics Data System (ADS)

As technology progresses, the demand for the usage of the electromagnetic spectrum increases with it. The development is so fast and prolific that clean band space for passive users such as Radio Astronomy is becoming ever so scarce. Even though, several spectral bands have been protected for Radio Astronomy by Federal Communication Commission (in the USA) under the recommendations of the International Telecommunication Union (ITU), pressure for making more spectral space commercially usable is extreme. Although these commercial usages make our modern living at all possible, often the extreme vulnerability of passive users are are not fully appreciated, resulting in unwanted emissions (RFI) in the Radio Astronomy Bands. Another source of RFI is the fact that many of the electronic devices used in the observatories themselves generate radio waves. If proper precautions are not taken, these can be received back through the Radio Telescope itself. This problem is referred to as internal RFI. The focus of this paper is the search and diminution of internal RFI in the Arecibo Observatory in Arecibo, Puerto Rico. Using a simple setup of a log-periodic antenna and a Spectrum Analyzer, spectra spanning a frequency range of 100 - 1800 MHZ were recorded in some areas of the Observatory and the new Visitor Center (AOVEF). The measurements disclosed sources of radio emission among some of the digital electronic equipment in the Equipment room and a few displays in the AOVEF. Most prominent of these was a 2.5 MHz comb spanning the entire range of the measurements emitted from the SRENDIP and AOFTM machines. The respective groups were informed and corrective shielding & isolations were implemented immediately. In AOVEF, three displays, some audio-visual equipment, and video/digital cameras used by the visitors were found to be "leaky". In future, the use of such cameras will be prohibited and the exhibits will be screened appropriately.

Acevedo, F.; Ghosh, Tapasi

1997-12-01

30

Basics of Radio Astronomy  

NSDL National Science Digital Library

This online workbook is used for training teachers and volunteers who wish to operate the Goldstone-Apple Valley Radio Telescope. The students in this district operate the telescope from the Apple Valley location. Also, students and teachers across the country can register to operate the telescope from their own classrooms. This workbook can also be used as a resource for information on how radio telescopes work, the fundamentals of the electromagnetic spectrum, thermal and non-thermal radiation, 21-cm hydrogen line, Kirchhoff's laws of spectral analysis, the Doppler effect, coordinate systems, and the SETI project.

Fisher, Diane

2004-07-16

31

Utrecht and Galactic Radio Astronomy  

NASA Astrophysics Data System (ADS)

Important roles in early Dutch Galactic radio astronomy were played by several Utrecht astronomers: Van de Hulst, Minnaert and Houtgast. The poster announcing the conference contained a number of pictures referring to scientific achievements of the Astronomical Institute Utrecht. One of these (Figure 1) appears to show the spiral structure of our Galaxy. Detailed comparison with the famous H I map (Figure 2), published by Oort, Kerr, and Westerhout (1958) in their paper The Galactic System as a Spiral Nebula, indicates that both are based on the same data. However, the OKW map resulted from work done at Kootwijk, Leiden and Sydney. What claim does Utrecht have to this pinnacle of early Galactic Radio Astronomy? Let us trace the history behind this H I map, as sketched in more detail by Van Woerden & Strom (2006).

van Woerden, H.

2013-01-01

32

Submillimeter receivers for radio astronomy  

Microsoft Academic Search

The state of development of receivers for submillimeter-wave radio astronomy is reviewed. Bolometers for continuum observation, hot-electron mixer receivers for narrowband spectral line observation, and heterodyne receivers, both Schottky diode and superconducting tunnel junction, are presented. At the lower frequency end of the submillimeter band, standard waveguide techniques, scaled from millimeter wavelengths, prevail. At wavelengths shorter than about 0.5 mm,

Raymond Blundell; CHEUK-YU EDWARD TONG

1992-01-01

33

The National Radio Astronomy Observatory  

Microsoft Academic Search

The history and facilities of the National Radio Astronomy Observatory (NRAO) are surveyed. The interferometer (near Green Bank, West Virginia) consists of three 85-foot antennas movable along a 2700-meter baseline, integrated with a 45-foot telescope 35 km distant. Simultaneous observations at 3.7 and 11.1 cm are possible. The 300-foot meridian-transit telescope, operating at 11 cm and longer wavelengths, has been

J. W. Findlay

1974-01-01

34

EVLA Memo 57 A Time Standard for Radio Astronomy  

E-print Network

George Henckel Adam Moritz Aaron Prager #12;Abstract The National Radio Astronomy Observatory?................................................................................3 3.2. The National Radio Astronomy ObservatoryEVLA Memo 57 A Time Standard for Radio Astronomy The New Mexico Array Final Report New Mexico

Groppi, Christopher

35

(Astro)Physics 343 Observational Radio Astronomy  

E-print Network

(Astro)Physics 343 Observational Radio Astronomy astrophysics course number = 01 will be on reserve in the physics library, and an online "Essential Radio Astronomy" course taught at the University. Other: a scientific calculator; access to a computer that can do numbercrunching with Excel or programs

Baker, Andrew J.

36

Radio Astronomy in Serbia: A Short Review  

NASA Astrophysics Data System (ADS)

In this lecture, I presented a short review of: 1. the brief history of development of radio astronomy in Serbia, and 2. the present state of research and university teaching in Serbia on this interesting and modern field of astronomy. Since 1970's, the continuum observations at the lowest radio frequencies (e.g. 38 MHz) and the Galactic radio loops have been represented the topics of main research interest for the first radio astronomer in Serbia, prof. dr Jelena Milogradov-Turin. In 1983, she introduced Radio astronomy as two semester course at 4th year of studies at Department of astronomy, Faculty of Mathematics, University of Belgrade. In this moment we have radio astronomy group with 5 (mainly younger) researchers from Department of Astronomy and Belgrade Astronomical Observatory. The main fields of research interest are, as a part of tradition, the Galactic radio loops and additionally, the hydrodynamic and radio evolution of supernova remnants. Our future projects will be connected with radio evolution of nova remnants and planetary nebulae.

Urosevic, D.

37

Voyager planetary radio astronomy studies  

NASA Technical Reports Server (NTRS)

Analysis of nonthermal radio emission data obtained by the Planetary Radio Astronomy (PRA) spectrometers on the Voyager 1 and 2 spacecraft was performed. This PRA data provided unique insights into the radio emission characteristics of the outer planets because of PRA's unique spectral response below the terrestrial ionospheric plasma frequency and its unprecedented proximity to the source. Of those results which were documented or published, this final report surveys only the highlights and cites references for more complete discussions. Unpublished results for Uranus, Neptune, and theoretical Ionian current distributions are presented at greater length. The most important conclusion to be drawn from these observations is that banded spectral emission is common to the radio emission below 1-2 MHz observed from all four Jovian planets. In every case multiple spectral features evolve on time scales of seconds to minutes. To the extent these features drift in frequency, they appear never to cross one another. The Neptunian spectral features appear to drift little or not at all, their evolution consisting principally of waxing and waning. Since other evidence strongly suggests that most or all of this radio emission is occurring near the local magnetospheric electron cyclotron frequency, this implies that this emission preferentially occurs at certain continually changing planetary radii. It remains unknown why certain radii might be favored, unless radial electric field components or other means serve to differentiate radially the magnetospheric plasma density, particle energy vectors, or particle coherence. Calculation of the spatial distribution and intensity of the Io-generated magnetospheric currents are also presented; these currents may be limited principally by wave impedance and local field strengths.

Staelin, David H.; Eikenberry, Stephen S.

1993-01-01

38

Expanding radio astronomy in Africa  

NASA Astrophysics Data System (ADS)

The Square Kilometre Array (SKA) Organisation announced in May 2012 that its members had agreed on a dual site solution for the SKA [1]. South Africa's bid for hosting the SKA has caused a ramp up of radio astronomy in Africa. To develop technology towards the SKA, the South African SKA Project (SKA SA) built a protoype radio telescope in 2007, followed in 2010 the seven antenna Karoo Array Telescope (KAT-7). Next is the 64 antenna MeerKAT, which will merge into SKA Phase 1 in Africa. As SKA Phase 2 is intended to add a high resolution capability with baselines out to 3000 km, the SKA SA brought in partner countries in Africa to host outstations. South Africa has been working with the partners to build capacity to operate the SKA and to benefit from it. The SA Department of Science and Technology (DST) developed a proposal to establish radio telescopes in the partner countries to provide hands-on learning and a capability for Very Long Baseline Interferometry (VLBI) research. Redundant 30 m class satellite antennas are being incorporated in this project.

Gaylard, M. J.

2013-04-01

39

Python Ephemeris Module for Radio Astronomy  

NASA Astrophysics Data System (ADS)

An extension of the Python pyephem module was developed for Deep Space Network (DSN) radio astronomy. The class DSS( ) provides the geodetic coordinates of the DSN stations as well as other properties such as antenna diameter. The class Quasar( ) provides positional data for the sources in the National Radio Astronomy Observatory Very Large Array (NRAO VLA) Calibrator Handbook and flux estimates based the University of Michigan Radio Astronomy Observatory (UMRAO) Database or the VLA Calibrator Handbook. Flux calibration data are also available for the bright planets. Class Pulsar( ) provides the data from the Australia Telescope National Facility (ATNF) Pulsar Catalogue in Python format.

Kuiper, T. B.

2013-05-01

40

Multichannel Interference Mitigation Techniques in Radio Astronomy  

Microsoft Academic Search

Radio-astronomical observations are increasingly corrupted by radio frequency interference, and on-line detection and filtering algorithms are becoming essential. To facilitate the introduction of such techniques into radio astronomy, we formulate the astronomical problem in an array signal processing language and give an introduction to some elementary algorithms from that field. We consider two topics in detail: interference detection by rank

Amir Leshem; Alle-Jan van der Veen; Albert-Jan Boonstra

2000-01-01

41

Planetary radio astronomy experiment for Voyager missions  

Microsoft Academic Search

The planetary radio astronomy experiment will measure radio spectra of planetary emissions in the range 1.2 kHz to 40.5 MHz. These emissions result from wave-particle-plasma interactions in the magnetospheres and ionospheres of the planets. At Jupiter, they are strongly modulated by the Galilean satellite Io.

J. W. Warwick; J. B. Pearce; R. G. Peltzer; A. C. Riddle

1977-01-01

42

The National Radio Astronomy Observatory \\/NRAO  

Microsoft Academic Search

The paper gives a brief discussion of the organization, operations, and physical facilities of the National Radio Astronomy Observatory (NRAO) in Deer Creek Valley, West Virginia. The telescopes at NRAO include an 85-ft equatorial telescope, a 300-foot transit telescope (the largest movable radio telescope in the world), a 140-foot equatorial telescope (also the largest of its kind), a calibration horn

W. R. Oref

1979-01-01

43

A Teaching Lab in Radio Astronomy  

ERIC Educational Resources Information Center

Describes a study in which participants in a summer institute for secondary science teachers performed a series of experiments with a radio telescope. Concludes that a radio astronomy teaching facility would encourage students to use their own initiative and strategy in working with the scientific concepts involved. (MLH)

Smith, Kirk R.; Cudaback, David D.

1976-01-01

44

Grote Reber, Radio Astronomy Pioneer, Dies  

NASA Astrophysics Data System (ADS)

Grote Reber, one of the earliest pioneers of radio astronomy, died in Tasmania on December 20, just two days shy of his 91st birthday. Reber was the first person to build a radio telescope dedicated to astronomy, opening up a whole new "window" on the Universe that eventually produced such landmark discoveries as quasars, pulsars and the remnant "afterglow" of the Big Bang. His self- financed experiments laid the foundation for today's advanced radio-astronomy facilities. Grote Reber Grote Reber NRAO/AUI photo "Radio astronomy has changed profoundly our understanding of the Universe and has earned the Nobel Prize for several major contributions. All radio astronomers who have followed him owe Grote Reber a deep debt for his pioneering work," said Dr. Fred Lo, director of the National Radio Astronomy Observatory (NRAO). "Reber was the first to systematically study the sky by observing something other than visible light. This gave astronomy a whole new view of the Universe. The continuing importance of new ways of looking at the Universe is emphasized by this year's Nobel Prizes in physics, which recognized scientists who pioneered X-ray and neutrino observations," Lo added. Reber was a radio engineer and avid amateur "ham" radio operator in Wheaton, Illinois, in the 1930s when he read about Karl Jansky's 1932 discovery of natural radio emissions coming from outer space. As an amateur operator, Reber had won awards and communicated with other amateurs around the world, and later wrote that he had concluded "there were no more worlds to conquer" in radio. Learning of Jansky's discovery gave Reber a whole new challenge that he attacked with vigor. Analyzing the problem as an engineer, Reber concluded that what he needed was a parabolic-dish antenna, something quite uncommon in the 1930s. In 1937, using his own funds, he constructed a 31.4-foot-diameter dish antenna in his back yard. The strange contraption attracted curious attention from his neighbors and became something of a minor tourist attraction, he later recalled. Using electronics he designed and built that pushed the technical capabilities of the era, Reber succeeded in detecting "cosmic static" in 1939. In 1941, Reber produced the first radio map of the sky, based on a series of systematic observations. His radio-astronomy work continued over the next several years. Though not a professional scientist, his research results were published in a number of prestigious technical journals, including Nature, the Astrophysical Journal, the Proceedings of the Institute of Radio Engineers and the Journal of Geophysical Research. Reber also received a number of honors normally reserved for scientists professionally trained in astronomy, including the American Astronomical Society's Henry Norris Russell Lectureship and the Astronomical Society of the Pacific's Bruce Medal in 1962, the National Radio Astronomy Observatory's Jansky Lectureship in 1975, and the Royal Astronomical Society's Jackson-Gwilt Medal in 1983. Reber's original dish antenna now is on display at the National Radio Astronomy Observatory's site in Green Bank, West Virginia, where Reber worked in the late 1950s. All of his scientific papers and records as well as his personal and scientific correspondence are held by the NRAO, and will be exhibited in the observatory's planned new library in Charlottesville, Virginia. Reber's amateur-radio callsign, W9GFZ, is held by the NRAO Amateur Radio Club. This callsign was used on the air for the first time since the 1930s on August 25, 2000, to mark the dedication of the Robert C. Byrd Green Bank Telescope. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

2002-12-01

45

"Radio Astronomy, Whatever That May Be." The Marginalization of Early Radio Astronomy  

NASA Astrophysics Data System (ADS)

Today we see radio astronomy as a fully-integrated part of astronomy; it is now just one of several available wavelength regimes and many astrophysicists who use radio data are not radio astronomers themselves. At the beginning, it was very different. Between 1946 and 1960, radio astronomy emerged as an important speciality but it was an area little understood by mainstream astronomers. Radio astronomers rarely published in astronomical journals, gave papers at astronomical conferences or were accorded much notice. The pioneers in the field were not astronomers themselves and had little in common with astronomers. In this paper I note the various ways in which radio astronomy was alienated from the mainstream in its first decade and some of the reasons this alienation occurred. I will also speculate on when and how the integration began to occur.

Jarrell, Richard

2005-01-01

46

Teaching radio astronomy with Affordable Small Radio Telescope (ASRT)  

NASA Astrophysics Data System (ADS)

A simple, easy to build and portable radio telescope, called Affordable Small Radio Telescope (ASRT), has been developed by the Radio Physics Laboratory (RPL), a radio astronomy teaching unit associated with the National Centre for Radio Astrophysics (TIFR) and Inter-University Centre for Astronomy and Astrophysics (IUCAA), which are two premier astronomy institutes in India. ASRT consists of off-the-shelf available Direct to Home television dishes and is easy to assemble. Our design is scalable from simple very low cost telescope to more complex yet moderately costing instrument. ASRT provides a platform for demonstrating radio physics concepts through simple hands-on experiment as well as for carrying out solar monitoring by college/University students. The presentation will highlight the concept of ASRT and the different experiments that can be carried out using it. The solar monitoring observations will be discussed along-with details of methods for calibrating these measurements. The pedagogical usefulness of ASRT in introducing undergraduatephysics students to astrophysics, measurements and analysis methods used in radio astronomy will also be discussed. Use of ASRT in the last three years in the programs of RPL, namely the annual Radio Astronomy Winter School for College students (RAWSC) and Pulsar Observing for Students (POS) is also presented. This year a new program was initiated to form a virtual group of an ASRT community, which will not only share their measurements, but also think of improving the pedagogical usefulness of ASRT by innovative experiments. This initiative is presented with the best practices drawn from our experience in using ASRT as a tool for student training in space sciences. The talk will also point out future ideas in involving a larger body of students in simple radio astronomy experiments with the ASRT, which RPL is likely to nucleate as part of its mandate.

Joshi, Bhal Chandra

47

A KALMANTRACKERBASED BAYESIAN DETECTOR FOR RADAR INTERFERENCE IN RADIO ASTRONOMY  

E-print Network

. Richard Fisher National Radio Astronomy Observatory P.O. Box 2, Green Bank, WV 24944 rfisher observatories . However, the induced pollution is impulsive and transient, so for radio astronomy observationA KALMAN­TRACKER­BASED BAYESIAN DETECTOR FOR RADAR INTERFERENCE IN RADIO ASTRONOMY Weizhen Dong

Wirthlin, Michael J.

48

The Radio JOVE Project: Inexpensive Radio Astronomy for the Classroom  

NASA Astrophysics Data System (ADS)

Radio JOVE is an interactive, hands-on educational activity for learning the scientific method through the medium of radio astronomy observations of Jupiter and the sun. Students build a radio telescope from a relatively inexpensive non-profit kit (about \\$125) and use it to record data, analyze the data, and share the results with others. Alternatively, for no cost, the students can record and analyze data from remote radio telescopes connected to the Web. The project is a useful adjunct to activities in optical astronomy since students should recognize that we learn about the Universe through more than just the optical spectrum. In addition to supplementing knowledge of Jupiter and the sun, the project teaches about charged particles and magnetic fields. Building of the kit is also a mini-course in electronics. The Radio JOVE website (http://radiojove.gsfc.nasa.gov) contains science information, instruction manuals, observing guides, software, and education resources for students and teachers.

Thieman, J. R.; Higgins, C. A.; Pine, W.

2000-12-01

49

Very Large Array, National Radio Astronomy Observatory  

Microsoft Academic Search

The Very Large Array (VLA), 80 km west of Socorro, NM, is one of the world's premier radio-astronomy facilities, offering researchers a unique combination of resolving power, sensitivity and observational flexibility. Dedicated in 1980, the VLA includes 27 25 m diameter dish antennas, arranged in a `Y' pattern, that work together as a single aperture-synthesis interferometric imaging system....

P. Murdin

2000-01-01

50

Meeting of the Radio Astronomy group, Cambridge, 2001 May 19  

NASA Astrophysics Data System (ADS)

A meeting of the Radio Astronomy group was held at the Institute of Astronomy, Cambridge on Saturday 2001 May 19. The meeting was to have been held at the Mullard Radio Astronomy Observatory, Cambridge, but due to foot and mouth restrictions the venue had to be changed. The last meeting of the Radio Astronomy Section had been held at MRAO in 1968. After informal conversations as the astronomers assembled lectures were given by university research staff on the latest developments in professional radio astronomy.

Brown, G.

2001-10-01

51

Curriculum Vitae Casey J. Law Radio Astronomy Lab  

E-print Network

Curriculum Vitae ­ Casey J. Law Radio Astronomy Lab University of California Hearst Field Annex ­ B://astro.berkeley.edu/claw 1 Education Northwestern University, Ph.D., Astrophysics (2007) Boston University, M.A., Astronomy: Radio Astronomy Lab Postdoctoral Fellow at UC Berkeley. Worked with Geoff Bower, Don Backer, and Carl

Militzer, Burkhard

52

Scott M. Ransom National Radio Astronomy Observatory / Univ. of Virginia  

E-print Network

Scott M. Ransom Astronomer National Radio Astronomy Observatory / Univ. of Virginia Scott is a tenured astronomer with the National Radio Astronomy Observatory (NRAO) in Charlottesville, VA where he studies all things "pulsar". He is also a Research Professor with the Astronomy Department

Groppi, Christopher

53

The interferometer in radio astronomy  

Microsoft Academic Search

A theory is developed for the response of a two-element radio interferometer to a partially coherent field, without restriction as to bandwidth or antenna properties. It is shown that for a completely incoherent source the narrow-band interferometer output is a component of the Fourier transform of the source brightness, which can therefore be mapped by repeated interferometer observations. A partially

N. C. Mathur

1968-01-01

54

Radio Science, Volume ???, Number , Pages 1?? , Radar Interference Blanking in Radio Astronomy using  

E-print Network

University, Provo, UT, USA J. R. Fisher National Radio Astronomy Observatory, Green Bank Observatory, WV, USARadio Science, Volume ???, Number , Pages 1?? , Radar Interference Blanking in Radio Astronomy and transient, so for radio astronomy observation, one solution is to "time-blank" by simply not includ- ing

Wirthlin, Michael J.

55

RadioNet: Advanced Radio Astronomy in Europe  

NSDL National Science Digital Library

RadioNet, an Integrated Infrastructure Initiative (I3), has brought together 20 of "Europe's leading astronomy facilities to produce a focused, coherent and integrated project that will significantly enhance the quality and quantity of science performed by European astronomers." After learning about the Initiative's many objectives, users can find brief summaries of the program's integration of astronomy pursuits in the areas of transnational access, joint research activities, and networking activities. The website presents press releases, upcoming and past events, and information on engineering, software, and Atacama Large (sub)-Millimeter Array (ALMA) forums. Users can also find out about the individual collaborators research activities through the external links.

56

Bayesian Detection of Radar Interference in Radio Astronomy  

E-print Network

@ee.byu.edu, wzhdong@hotmail.com) and J. Richard Fisher National Radio Astronomy Observatory, 520 Edgemont Road1 Bayesian Detection of Radar Interference in Radio Astronomy Brian D. Jeffs, Weizhen Lazarte (GBT) and other radio observatories are often made in frequency bands allocated to aviation pulsed

Wirthlin, Michael J.

57

Planetary radio astronomy observations from Voyager 1 near Saturn  

Microsoft Academic Search

The Voyager 1 planetary radio astronomy experiment detected two distinct kinds of radio emissions from Saturn. The first, Saturn kilometric radiation, is strongly polarized, bursty, tightly correlated with Saturn's rotation, and exhibits complex dynamic spectral features somewhat reminiscent of those in Jupiter's radio emission. It appears in radio frequencies below about 1.2 megahertz. The second kind of radio emission, Saturn

J. W. Warwick; J. B. Pearce; D. R. Evans; T. D. Carr; J. J. Schauble; J. K. Alexander; M. L. Kaiser; M. D. Desch; M. Pedersen; A. Lecacheux; G. Daigne; A. Boischot; C. H. Barrow

1981-01-01

58

The beginnings of Australian radio astronomy  

NASA Astrophysics Data System (ADS)

The early stages of Australian radio astronomy, especially the first decade after World War II, are described in detail. These include the transition of the CSIRO Radiophysics Laboratory, under the leadership of Joseph Pawsey and Taffy Bowen, from a wartime laboratory in 1945 to, by 1950, the largest and one of the two most important radio astronomy groups in the world (with the Cavendish Laboratory at Cambridge University). The initial solar investigations are described, including discovery of the hot corona and development of the sea-cliff interferometer. During this same period painstaking `radio star' observations by John Bolton and colleagues led to the first suggested optical identifications of Taurus-A (the Crab Nebula), Centaurus-A (NGC 5128), and Virgo-A (M87). The factors that led to the extraordinary early success of the Radiophysics Laboratory are analyzed in detail, followed by discussion of how the situation changed significantly in the second decade of 1955-1965. Finally, the development of major Australian instruments, from the Parkes Radio Telescope (1961) to the Australia Telescope (1988), is briefly presented.

Sullivan, Woodruff T.

2005-06-01

59

47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.  

Code of Federal Regulations, 2010 CFR

... Notification of the National Radio Astronomy Observatory. 5.91 Section 5... Notification of the National Radio Astronomy Observatory. In order to minimize...harmful interference at the National Radio Astronomy Observatory site located at...

2010-10-01

60

47 CFR 73.1030 - Notifications concerning interference to radio astronomy, research and receiving installations.  

Code of Federal Regulations, 2014 CFR

...interference at the National Radio Astronomy Observatory site located at Green...Interference Office, National Radio Astronomy Observatory, P.O...20-day period from the National Radio Astronomy Observatory for itself, or...

2014-10-01

61

47 CFR 5.91 - Notification to the National Radio Astronomy Observatory.  

Code of Federal Regulations, 2014 CFR

...Notification to the National Radio Astronomy Observatory. 5.91 Section...Notification to the National Radio Astronomy Observatory. In order to...interference at the National Radio Astronomy Observatory site located at...

2014-10-01

62

47 CFR 5.91 - Notification to the National Radio Astronomy Observatory.  

Code of Federal Regulations, 2013 CFR

...Notification to the National Radio Astronomy Observatory. 5.91 Section...Notification to the National Radio Astronomy Observatory. In order to...interference at the National Radio Astronomy Observatory site located at...

2013-10-01

63

47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.  

Code of Federal Regulations, 2011 CFR

...Notification of the National Radio Astronomy Observatory. 5.91 Section...Notification of the National Radio Astronomy Observatory. In order to...interference at the National Radio Astronomy Observatory site located at...

2011-10-01

64

47 CFR 5.91 - Notification of the National Radio Astronomy Observatory.  

Code of Federal Regulations, 2012 CFR

...Notification of the National Radio Astronomy Observatory. 5.91 Section...Notification of the National Radio Astronomy Observatory. In order to...interference at the National Radio Astronomy Observatory site located at...

2012-10-01

65

Project CLEA: Radio Astronomy of Pulsars  

NSDL National Science Digital Library

This software for Windows, from Project CLEA -- Contemporary Laboratory Experiences In Astronomy, presents students with a radio telescope. The default operating characteristics (beam width, receiver noise, steerability) can be set by the instructor. Students can point the telescope at a source in the sky, viewing the output of the radio receiver on a graphic display that resembles a digital oscilloscope. The student manual describes exercises in which students acquaint themselves with the operation of the radio telescope, measure the signals from several pulsars at various frequencies, learn about pulsar signals, and then estimate the distance to the pulsar. The site includes student and instructor manuals as well as a pre- and posttest. The software is available for Windows only.

66

The Importance of Site Selection for Radio Astronomy  

NASA Astrophysics Data System (ADS)

Radio sources are very weak since this object travel very far from outer space. Radio astronomy studies are limited due to radio frequency interference (RFI) that is made by man. If the harassment is not stopped, it will provide critical problems in their radio astronomy scientists research. The purpose of this study is to provide RFI map Peninsular Malaysia with a minimum mapping techniques RFI interference. RFI mapping technique using GIS is proposed as a tool in mapping techniques. Decision-making process for the selection requires gathering information from a variety of parameters. These factors affecting the selection process are also taken account. In this study, various factors or parameters involved such as availability of telecommunications transmission (including radio and television), rainfall, water line and human activity. This study will benefit radio astronomy research especially in the RFI profile in Malaysia. Keywords: Radio Astronomy, Radio Frequency Interference (RFI), RFI mapping technique : GIS.

Umar, Roslan; Zainal Abidin, Zamri; Abidin Ibrahim, Zainol

2014-10-01

67

The History of Radio Astronomy and the National Radio Astronomy Observatory: Evolution Toward Big Science  

Microsoft Academic Search

The purpose of this study is to examine the sequence of events that led to the establishment of the NRAO, the construction and development of instrumentation and the contributions and discovery events and to relate the significance of these events to the evolution of the sciences of radio astronomy and cosmology. After an overview of the resources, a brief discussion

Benjamin Kevin Malphrus

1990-01-01

68

Astronomy 4194 Group Studies Essential Radio Astronomy Syllabus for May Term 2014 Prof. Martini Page 1 of 2  

E-print Network

Astronomy 4194 ­ Group Studies ­ Essential Radio Astronomy ­ Syllabus for May Term 2014 ­ Prof. Martini Page 1 of 2 Astronomy 4194 ­ Group Studies ­ Essential Radio Astronomy Syllabus for May Term 2014. Paul Martini, Dept. of Astronomy Office: 4021 McPherson Lab (4th floor), mailbox in 4055 McPherson Lab

Martini, Paul

69

A new signal processing platform for radio astronomy  

Microsoft Academic Search

Context: We describe the concept, construction, and testing of TasPGA, a new, versatile digital signal processing device designed for radio astronomy applications. Aims: A minimalist design philosophy was used to develop a general-purpose radio astronomy instrument based on field programmable gate array (FPGA) technology. The design emphasises reliability and flexibility, facilitating the rapid development of new FPGA firmware for a

A. W. Hotan

2008-01-01

70

Highlighting the History of Japanese Radio Astronomy: 1: An Introduction  

NASA Astrophysics Data System (ADS)

Japan was one of a number of nations that made important contributions in the fledgling field of radio astronomy in the years immediately following WWII. In this paper we discuss the invention of the Yagi-Uda antenna and the detection of solar radio emission in 1938, before reviewing radio astronomical developments that occurred between 1948 and 1961 in Osaka, Nagoya, Tokyo and Hiraiso. In order to place these early Japanese experiments in a national and international context we briefly review the world-wide development of radio astronomy in the immediate post-War years before discussing the growth of optical astronomy in Japan at this time.

Ishiguro, Masato; Orchiston, Wayne; Akabane, Kenji; Kaifu, Norio; Hayashi, Masa; Nakamura, Tsuko; Stewart, Ronald; Yokoo, Hiromitsu

2012-11-01

71

Radio Astronomy Software Defined Receiver Project  

SciTech Connect

The paper describes a Radio Astronomy Software Defined Receiver (RASDR) that is currently under development. RASDR is targeted for use by amateurs and small institutions where cost is a primary consideration. The receiver will operate from HF thru 2.8 GHz. Front-end components such as preamps, block down-converters and pre-select bandpass filters are outside the scope of this development and will be provided by the user. The receiver includes RF amplifiers and attenuators, synthesized LOs, quadrature down converters, dual 8 bit ADCs and a Signal Processor that provides firmware processing of the digital bit stream. RASDR will interface to a user s PC via a USB or higher speed Ethernet LAN connection. The PC will run software that provides processing of the bit stream, a graphical user interface, as well as data analysis and storage. Software should support MAC OS, Windows and Linux platforms and will focus on such radio astronomy applications as total power measurements, pulsar detection, and spectral line studies.

Vacaliuc, Bogdan [ORNL] [ORNL; Leech, Marcus [Shirleys Bay Radio Astronomy Consortium] [Shirleys Bay Radio Astronomy Consortium; Oxley, Paul [Retired] [Retired; Flagg, Richard [Retired] [Retired; Fields, David [ORNL] [ORNL

2011-01-01

72

JPL Big Data Technologies for Radio Astronomy  

NASA Astrophysics Data System (ADS)

During the past three years the Jet Propulsion Laboratory has been working on several technologies to deal with big data challenges facing next-generation radio arrays, among other applications. This program has focused on the following four areas: 1) We are investigating high-level ASIC architectures that reduce power consumption for cross-correlation of data from large interferometer arrays by one to two orders of magnitude. The cost of operations for the Square Kilometre Array (SKA), which may be dominated by the cost of power for data processing, is a serious concern. A large improvement in correlator power efficiency could have a major positive impact. 2) Data-adaptive algorithms (machine learning) for real-time detection and classification of fast transient signals in high volume data streams are being developed and demonstrated. Studies of the dynamic universe, particularly searches for fast (<< 1 second) transient events, require that data be analyzed rapidly and with robust RFI rejection. JPL, in collaboration with the International Center for Radio Astronomy Research in Australia, has developed a fast transient search system for eventual deployment on ASKAP. In addition, a real-time transient detection experiment is now running continuously and commensally on NRAO's Very Long Baseline Array. 3) Scalable frameworks for data archiving, mining, and distribution are being applied to radio astronomy. A set of powerful open-source Object Oriented Data Technology (OODT) tools is now available through Apache. OODT was developed at JPL for Earth science data archives, but it is proving to be useful for radio astronomy, planetary science, health care, Earth climate, and other large-scale archives. 4) We are creating automated, event-driven data visualization tools that can be used to extract information from a wide range of complex data sets. Visualization of complex data can be improved through algorithms that detect events or features of interest and autonomously generate images or video to display those features. This work has been carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

Jones, Dayton L.; D'Addario, L. R.; De Jong, E. M.; Mattmann, C. A.; Rebbapragada, U. D.; Thompson, D. R.; Wagstaff, K.

2014-04-01

73

IAU DIVISION X, XII / COMMISSION 40, 41 / WORKING GROUP on HISTORICAL RADIO ASTRONOMY  

E-print Network

Radio Astronomy Observatory initiated the first Archives de voted exclusively to radio astronomy- institutional collaborations. As the national facility for radio astronomy, the Archives also includesIAU DIVISION X, XII / COMMISSION 40, 41 / WORKING GROUP on HISTORICAL RADIO ASTRONOMY CHAIR Kenneth

Groppi, Christopher

74

The Deep Space Network: An instrument for radio astronomy research  

NASA Technical Reports Server (NTRS)

The NASA Deep Space Network operates and maintains the Earth-based two-way communications link for unmanned spacecraft exploring the solar system. It is NASA's policy to also make the Network's facilities available for radio astronomy observations. The Network's microwave communication systems and facilities are being continually upgraded. This revised document, first published in 1982, describes the Network's current radio astronomy capabilities and future capabilities that will be made available by the ongoing Network upgrade. The Bibliography, which includes published papers and articles resulting from radio astronomy observations conducted with Network facilities, has been updated to include papers to May 1987.

Renzetti, N. A.; Levy, G. S.; Kuiper, T. B. H.; Walken, P. R.; Chandlee, R. C.

1988-01-01

75

Noise Levels at the National Radio Astronomy Observatory  

Microsoft Academic Search

The measurements which have been made of the field strengths of radio signals received at the Green Bank site of the National Radio Astronomy Observatory are described. The site is relatively free from interference and the measures which are being adopted to preserve its radio quietness are discussed.

J. W. Findlay

1958-01-01

76

Radio Astronomy Imagery for Education and Public Outreach  

Microsoft Academic Search

The National Radio Astronomy Observatory (NRAO) has initiated an Education and Public Outreach (EPO) program to improve its capability to process radio-wavelength astronomical data into compelling visual imagery and to make such imagery readily accessible and widely available to scientists, students, teachers, the general public, the media, and EPO professionals. This imagery initiative is exploring radio data visualization techniques and

M. T. Adams; D. G. Finley; A. Gianopoulos; P. Smiley; W. Saxton; J. M. Uson

2005-01-01

77

Spectrum control procedures for the national radio astronomy observatory  

Microsoft Academic Search

The Green Bank site for the National Radio Astronomy Observatory (NRAO) and the Sugar Grove site for the Naval Radio Research Laboratory (NRRL) were located fairly close together with the hope that both could share in the locally relatively low radio noise environment that existed when the installations were first built. The procederes which have been followed to maintain, as

JAMES L. DOLAN

1973-01-01

78

Low Frequency Radio Astronomy with the existing and future radio telescopes  

E-print Network

Low Frequency Radio Astronomy with the existing and future radio telescopes A.A. Konovalenko radio telescope and also the creation of new large telescope of 10 ­ 70 MHz frequency range, Emmen, "Astrophisycs in the LOFAR era") #12;#12;#12;The low-frequency radio telescopes in Europe LOFAR

Demoulin, Pascal

79

Sixty Years in radio astronomy: A tribute to Bruce Slee  

NASA Astrophysics Data System (ADS)

Bruce Slee is one of the pioneers of radio astronomy. After recording solar emission during World War II, he joined what was then the Council of Scientific and Industrial Research's Division of Radiophysics in Sydney, Australia, and went on to make important contributions to Solar System, Galactic and extra-galactic astronomy. Since his retirement, in 1989, he has continued his research as an Honorary Fellow of the Australia Telescope National Facility. Now in his early 80s, Bruce Slee is one of the few radio astronomy pioneers of the 1940s who is still actively contributing to astrophysics. This issue of the Journal of Astronomical History and Heritage (JAH2), and the two that will follow it, are a tribute to this quietly-spoken scientist and his remarkable 60-year involvement in radio astronomy.

Orchiston, Wayne

2005-06-01

80

Communicating radio astronomy with the public: Another point of view  

NASA Astrophysics Data System (ADS)

Radio waves cannot be sensed directly, but they are used in daily life by almost everybody. Even so, the majority of the general public do not even know that celestial bodies emit radio waves. Presenting invisible radiation to a general audience with little or no background knowledge in physics is a difficult task. In addition, much important technology now commonplace in many other scientific fields was pioneered by radio observatories in their efforts to detect and process radio signals from the Universe. Radio astronomy outreach does not have such a well-established background as optical astronomy outreach. In order to make radio astronomy accessible to the public, it is necessary either to add more scientific detail or to find a different way of communicating. In this paper we present examples from our work at the Visitor Centre "Marcello Ceccarelli", which is part of the Medicina Radio Observatory, operated by the Institute of Radio Astronomy (IRA) in Bologna, which in turn is part of the National Institute for Astrophysics (INAF).

Varano, S.

2008-06-01

81

47 CFR 73.6027 - Class A TV notifications concerning interference to radio astronomy, research and receiving...  

Code of Federal Regulations, 2011 CFR

...notifications concerning interference to radio astronomy, research and receiving installations...notifications concerning interference to radio astronomy, research and receiving installations...Notifications concerning interference to radio astronomy, research and receiving...

2011-10-01

82

47 CFR 73.6027 - Class A TV notifications concerning interference to radio astronomy, research and receiving...  

Code of Federal Regulations, 2014 CFR

...notifications concerning interference to radio astronomy, research and receiving installations...notifications concerning interference to radio astronomy, research and receiving installations...Notifications concerning interference to radio astronomy, research and receiving...

2014-10-01

83

47 CFR 73.6027 - Class A TV notifications concerning interference to radio astronomy, research and receiving...  

Code of Federal Regulations, 2013 CFR

...notifications concerning interference to radio astronomy, research and receiving installations...notifications concerning interference to radio astronomy, research and receiving installations...Notifications concerning interference to radio astronomy, research and receiving...

2013-10-01

84

47 CFR 73.6027 - Class A TV notifications concerning interference to radio astronomy, research and receiving...  

Code of Federal Regulations, 2012 CFR

...notifications concerning interference to radio astronomy, research and receiving installations...notifications concerning interference to radio astronomy, research and receiving installations...Notifications concerning interference to radio astronomy, research and receiving...

2012-10-01

85

47 CFR 73.6027 - Class A TV notifications concerning interference to radio astronomy, research and receiving...  

Code of Federal Regulations, 2010 CFR

...notifications concerning interference to radio astronomy, research and receiving installations...notifications concerning interference to radio astronomy, research and receiving installations...Notifications concerning interference to radio astronomy, research and receiving...

2010-10-01

86

International Agreement Will Advance Radio Astronomy  

NASA Astrophysics Data System (ADS)

Two of the world's leading astronomical institutions have formalized an agreement to cooperate on joint efforts for the technical and scientific advancement of radio astronomy. The National Radio Astronomy Observatory (NRAO) in the United States and the Max-Planck Institute for Radioastronomy (MPIfR) in Germany concluded a Memorandum of Understanding outlining planned collaborative efforts to enhance the capabilities of each other's telescopes and to expand their cooperation in scientific research. The VLBA The VLBA CREDIT: NRAO/AUI/NSF In the first project pursued under this agreement, the MPIfR will contribute $299,000 to upgrade the continent-wide Very Long Baseline Array's (VLBA) capability to receive radio emissions at a frequency of 22 GHz. This improvement will enhance the VLBA's scientific productivity and will be particularly important for cutting-edge research in cosmology and enigmatic cosmic objects such as gamma-ray blazars. "This agreement follows many years of cooperation between our institutions and recognizes the importance of international collaboration for the future of astronomical research," said Fred K.Y. Lo, NRAO Director. "Our two institutions have many common research goals, and joining forces to keep all our telescopes at the forefront of technology will be highly beneficial for the science," said Anton Zensus, Director at MPIfR. In addition to the VLBA, the NRAO operates the Very Large Array (VLA) in New Mexico and the Robert C. Byrd Green Bank Telescope (GBT) in West Virginia. The MPIfR operates the 100-meter Effelsberg Radio Telescope in Germany and the 12-meter APEX submillimeter telescope in 5100 m altitude in the Cilean Atacama desert (together with the European Southern Observatory and the Swedish Onsala Space Observatory). With the 100-meter telescope, it is part of the VLBA network in providing transatlantic baselines. Both institutions are members of a global network of telescopes (the Global VLBI Network) that uses simultaneous observations to produce extremely high-resolution images, and another network (the High Sensitivity Array) that uses the same technique with large telescopes to observe particularly faint celestial objects. With this technique, NRAO telescopes work with MPIfR's Effelsberg telescope to produce images hundreds of times more detailed than those from the Hubble Space Telescope. Both institutions also are part of the international collaboration building the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile and of the international planning effort to build a Square Kilometer Array. The VLBA is a system of ten antennas, each with a dish 25 meters in diameter. From Mauna Kea on the Big Island of Hawaii to St. Croix in the U.S. Virgin Islands, the VLBA spans more than 8000 kilometers. Under the new agreement, the two institutions will continue their previous observational collaborations, and in addition will share resources to improve the technical capabilities of each other's telescopes, particularly at short wavelengths, They also will collaborate in the peer-reviewed process each uses to allocate observing time, and agree to mutually maintain an "open skies" policy allowing open access to each other's telescopes on a peer-reviewed basis. The agreement notes the report of the U.S. National Science Foundation's (NSF) Senior Review committee, which called upon the NRAO to seek partners to contribute to the operation of the VLBA. The MPIfR affirms its strong interest in maintaining the VLBA's unique scientific capabilities, and its monetary contribution toward the 22 GHz upgrade of the VLBA is a solid sign of that commitment. "The VLBA provides the greatest resolving power of any instrument in astronomy, and the MPIfR's contribution to enhancing its capabilities is an important validation of the VLBA's importance to frontier astrophysics," Lo said. The joint VLBA project calls for the MPIfR to fund the receiving-system upgrades and the NRAO to perform the work. The project is scheduled to be complete, with all 10 VLBA an

2007-12-01

87

An automatic radio interference monitor for the National Radio Astronomy Observatory Very Large Array  

Microsoft Academic Search

The National Radio Astronomy Observatory (NRAO) operates the Very Large Array (VLA) Radio Observatory on the Plains of San Augustin in New Mexico, and the Very Long Baseline Array (VLBA) with 10 antenna locations from Hawaii to St. Croix. Harmful radio frequency interference (RFI) is a growing problem for the VLA and the VLBA, and for that matter, all Earth-based

C. C. Janes; R. A. Jones; W. D. Brundage

1995-01-01

88

Sub-arcsecond radio astronomy. Proceedings.  

NASA Astrophysics Data System (ADS)

Contents: I. Galactic astronomy. 1. Stars. 2. The Galactic Center. 3. Masers and molecules. 4. Plasma effects. II. Extragalactic astronomy. 1. Gravitational lenses. 2. Compact structure in AGN. 3. Intermediate scale structure. 4. AGN at other wavelengths. 5. Mildly active galaxies. 6. Theory and jet simulation. III. Cosmology. IV. Astrometry. V. Instruments and techniques.

Davis, R. J.; Booth, R. S.

89

Sub-arcsecond radio astronomy. Proceedings  

Microsoft Academic Search

Contents: I. Galactic astronomy. 1. Stars. 2. The Galactic Center. 3. Masers and molecules. 4. Plasma effects. II. Extragalactic astronomy. 1. Gravitational lenses. 2. Compact structure in AGN. 3. Intermediate scale structure. 4. AGN at other wavelengths. 5. Mildly active galaxies. 6. Theory and jet simulation. III. Cosmology. IV. Astrometry. V. Instruments and techniques.

R. J. Davis; R. S. Booth

1993-01-01

90

Interference Mitigation In Radio Astronomy and  

E-print Network

radio telescope (in his backyard!) and makes the first sky maps #12;First Sky Maps at Radio Frequencies? A typical major radio telescope costs on the order of US$20,000 per day to operate Post-observation editing radio telescopes, so telescope time has value that transcends simple dollar estimates In summary: Real

Ellingson, Steven W.

91

National Radio Astronomy Observatory P.O. Box O, 1003 Lopezville Rd, Socorro, NM 87801, USA  

E-print Network

National Radio Astronomy Observatory P.O. Box O, 1003 Lopezville Rd, Socorro, NM 87801, USA Astro., Astro 2010 position paper, The Impact of the National Radio Astronomy Observatory) for scientific for radio astronomy. This is one of five papers outlining for the Program Prioritization Panel a series

Ellingson, Steven W.

92

National Radio Astronomy Observatory 22 May 2008 US SKA Consortium Meeting, DC  

E-print Network

National Radio Astronomy Observatory 22 May 2008 ­ US SKA Consortium Meeting, DC The Role of NRAO in SKA Fred Lo #12;National Radio Astronomy Observatory 22 May 2008 ­ US SKA Consortium Role of NRAO;National Radio Astronomy Observatory 22 May 2008 ­ US SKA Consortium Relationship with community

Groppi, Christopher

93

AMANDA ANN KEPLEY MAIL: National Radio Astronomy Observatory OFFICE: +1-304-456-2808  

E-print Network

AMANDA ANN KEPLEY MAIL: National Radio Astronomy Observatory OFFICE: +1-304-456-2808 P Grant 2012 National Radio Astronomy Observatory Foreign Telescope Fund Grant 2009, 2010 Green Bank Knapp Jansky Award 2006 RESEARCH EMPLOYMENT National Radio Astronomy Observatory Postdoctoral Fellow 9

Groppi, Christopher

94

To: Fred Lo, Director, National Radio Astronomy Observatory From: NRAO Users Committee 2004,  

E-print Network

To: Fred Lo, Director, National Radio Astronomy Observatory From: NRAO Users Committee 2004, John The Users Committee of the National Radio Astronomy Observatory met on May 24-25, 2004, in Charlottesville facilities and support of the highest quality to the US radio astronomy community. The committee commends

Groppi, Christopher

95

RADIO ASTRONOMY OBSERVATORYNAT IONA TI TLE: VANE TYPE POLARIZATION CONVERTER  

E-print Network

RADIO ASTRONOMY OBSERVATORYNAT IONA TI TLE: VANE TYPE POLARIZATION CONVERTER AUTHOR (S) C1 BROCKWAY perpendicular to vanes Propagation direction #12;= c= 1)(2. 2 2. Phase Shift (1)1_ = d = (w/vc) d (radians) (1 spacing so v > v c ). = radian frequency. = propagation constant (Pi- (P11 E Acp = wd (l/vc - 1/v). Acp

Groppi, Christopher

96

Planetary radio astronomy observations from Voyager 2 near Jupiter  

Microsoft Academic Search

The Voyager 2 Planetary Radio Astronomy experiment to Jupiter has confirmed and extended to higher zenomagnetic latitudes results from the identical experiment carried by Voyager 1. The kilometric emissions discovered by Voyager 1 often extended to 1 megahertz or higher on Voyager 2 and often consisted of negatively, or less frequently, positively drifting narrowband bursts. On the basis of tentative

J. W. Warwick; J. B. Pearce; A. C. Riddle; J. K. Alexander; M. D. Desch; M. L. Kaiser; J. R. Thieman; T. D. Carr; S. Gulkis; A. Boischot; Y. LEBLANC; B. M. PEDERSEN; D. H. STAELIN

1979-01-01

97

NATIONAL RADIO ASTRONOMY OBSERVATORY GREEN BANK, WEST VIRGINIA  

E-print Network

on the outside of the vertex cabin (see Figure 2). The air handler houses the cooling coil, the 15 kW heaterNATIONAL RADIO ASTRONOMY OBSERVATORY GREEN BANK, WEST VIRGINIA ELECTRONICS DIVISION INTERNAL REPORT. COOLING COIL SCR PROPORTIONAL CONTROLER ) --110-40- CONDITIONED AIR THERMISTOR SENSORS 15 K W IN VERTEX

Groppi, Christopher

98

A Radio Astronomy Curriculum for the Middle School Classroom  

Microsoft Academic Search

In the summer of 2000, two teachers working on a Masters of Science Teaching program at New Mexico Institute of Mining and Technology, spent eight weeks as interns at the Array Operations Center for the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico, under the auspices of the National Science Foundation's (NSF) Research Experience for Teachers (RET) program. The

J. Davis; D. G. Finley

2000-01-01

99

The IAU Early Japanese Radio Astronomy Project: A Progress Report  

NASA Astrophysics Data System (ADS)

Japan was one of those nations that make an early start in radio astronomy, when solar observations began at both the Tokyo Astronomical Observatory (TAO) and at Osaka University in 1949. The research at the TAO accelerated during the 1950s and 1960s under the capable direction of Professor Hatanaka, while an equally-vibrant program was developed independently at Toyokawa by Professor Tanaka from Nagoya University. In this paper, after briefly describing the Osaka University initiative we will outline the instruments developed at Toyokawa and Mitaka, review the research programs carried out with them and introduce the scientific staff who played so important a role in the early development of Japanese radio astronomy. Following the success of the WG's Early French Radio Astronomy Project (seven papers were published), an ambitious IAU project to systematically document early developments in Japanese radio astronomy and publish the results in a series of research papers in the Journal of Astronomical History and Heritage was launched in December 2010. Further research visits to Tokyo were made by the second author in 2011 and 2012, and two papers have now been completed and a start made on a third.

Ishiguro, Masato; Orchiston, Wayne; Akabane, Kenji; Stewart, Ron

2012-09-01

100

Starting with Nothing: Archives at National Radio Astronomy Observatory  

Microsoft Academic Search

Founded in 1956, National Radio Astronomy Observatory had no Archivist or Archives program until mid-2003, when the new Archivist, working less than half time, began building the collection. Our institutional records were scattered between multiple storage areas at NRAO sites in four different states, and no one knew what we had. Personal papers of pioneers and participants in the development

E. N. Bouton

2007-01-01

101

Using many-core hardware to correlate radio astronomy signals  

Microsoft Academic Search

A recent development in radio astronomy is to replace traditional dishes withmany small antennas. The signals are combined toform one large, virtual telescope. The enormous data streams are cross- correlated to filter out noise. This is especially challenging, since the computational demands grow quadratically with the number of data streams. Moreover, the correlator is not only computationally intensive, but also

Rob V. Van Nieuwpoort; John W. Romein

2009-01-01

102

The Effelsberg 100-m Radio Telescope: Construction and Forty Years of Radio Astronomy  

NASA Astrophysics Data System (ADS)

The Effelsberg 100-m dish represents a major breakthrough in the technology of radio telescope construction. Using new methods of computation a big step in the direction of improved surface accuracy for large structures was achieved. In conjunction with the decision to build the 100-m radio telescope the Max-Planck-Gesellschaft (MPG) founded the Max-Planck-Institute for Radio Astronomy (MPIfR) in Bonn. The MPIfR grew out of the Bonn University Astronomy Department to become one of the leading institutes for radio astronomy in the world. This new institute received strong support from the MPG in the form of new positions and operating funds. As a result, the 100-m radio telescope could be quickly opened up for astronomical observations. The technical divisions provided state-of-the-art receivers and astronomical software. Teams of astronomical researchers made inroads in several important directions of astronomical research. Over the years virtually all the observing methods of radio astronomy were implemented at Effelsberg. In later years the MPIfR became involved in mm, sub-mm and infrared astronomy research. However, the 100-m radio telescope remained the `work horse' of the Institute. The Effelsberg Radio Telescope will celebrate its 40th anniversary of operations in May 2011 and is still going strong. The observations with the 100-m radio telescope have resulted in thousands of publications. It has served several generations of radio astronomers and has given hundreds of students the opportunity to complete doctoral degrees. The 100-m radio telescope has been upgraded continuously, is in excellent condition and can look to a further period as an important research instrument.

Wielebinski, Richard; Junkes, Norbert; Grahl, Berndt H.

2011-03-01

103

Ionospheric wave and irregularity measurements using passive radio astronomy techniques  

NASA Technical Reports Server (NTRS)

The observation of midlatitude structures using passive radio astronomy techniques is discussed, with particular attention being given to the low-frequency radio telescope at the Clark Lake Radio Observatory. The present telescope operates in the 10-125-MHz frequency range. Observations of the ionosphere at separations of a few kilometers to a few hundreds of kilometers by the lines of sight to sources are possible, allowing the determination of the amplitude, wavelength, direction of propagation, and propagation speed of ionospheric waves. Data are considered on large-scale ionospheric gradients and the two-dimensional shapes and sizes of ionospheric irregularities.

Erickson, W. C.; Mahoney, M. J.; Jacobson, A. R.; Knowles, S. H.

1988-01-01

104

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLE, VIRGINIA  

E-print Network

astronomy receivers are constructed using a cryogenically cooled mixer as the first stage, followed by a low of the mixers constructed at NRAO is the L-band cooled FET amplifier reported by Weinreb, Fenstermacher to quadrature 3 dB hybrids, as shown in Figure 1. In this configuration, reflections from the input (output

Groppi, Christopher

105

A Virtual Tour of the Radio Astronomy Process  

NASA Astrophysics Data System (ADS)

In the summer of 2000, two teachers working on a Masters of Science Teaching Degree at New Mexico Tech and participating in the Research Experience for Teachers (RET) program sponsored by the National Science Foundation, spent eight weeks as interns researching and working on projects at the National Radio Astronomy Observatory (NRAO) which will directly benefit students in their classrooms and also impact other science educators. One of the products of the interships is a set of web pages for NRAO's web page educational section. The purpose of these web pages is to familiarize students, teachers, and other people with the process that a radio astronomer goes through to do radio astronomy science. A virtual web tour was created of this process. This required interviewing radio astronomers and other professionals involved with this process at the NRAO (e.g. engineers, data analysts, and operations people), and synthesizing the interviews into a descriptive, visual-based set of web pages. These pages do meet the National as well as New Mexico Standards and Benchmarks for Science Education. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc. The NSF's RET program is gratefully acknowledged.

Conrad, S. B.; Finley, D. G.; Claussen, M. J.; Ulvestad, J. S.

2000-12-01

106

A new signal processing platform for radio astronomy  

NASA Astrophysics Data System (ADS)

Context: We describe the concept, construction, and testing of TasPGA, a new, versatile digital signal processing device designed for radio astronomy applications. Aims: A minimalist design philosophy was used to develop a general-purpose radio astronomy instrument based on field programmable gate array (FPGA) technology. The design emphasises reliability and flexibility, facilitating the rapid development of new FPGA firmware for a wide range of experiments. Methods: Hardware and firmware for TasPGA were designed using software provided by Altium Ltd. and Xilinx Inc. We tested the instrument by implementing a Fourier transform spectrometer capable of dividing 100 MHz of bandwidth into 16 384 channels. Results: We present data taken with a TasPGA spectrometer at the Mt. Pleasant radio observatory, including the spectra of two astronomical methanol masers.

Hotan, A. W.

2008-07-01

107

Bernard Mills and Australian radio astronomy  

NASA Astrophysics Data System (ADS)

Bernard Mills, in conversation with Ragbir Bhathal, recalls how he became an astronomer by accident after the second world war, devised the Mills Cross radio telescope as a way to get a good instrument on the cheap, and what happened when he questioned the methods of Cambridge radio astronomers at the time of Martin Ryle's 2C catalogue.

Bhathal, Ragbir

2012-04-01

108

The importance of Radio Quiet Zone (RQZ) for radio astronomy  

NASA Astrophysics Data System (ADS)

Most of radio observatories are located in isolated areas. Since radio sources from the universe is very weak, astronomer need to avoid radio frequency interference (RFI) from active spectrum users and radio noise produced by human made (telecommunication, mobile phone, microwave user and many more. There are many observatories around the world are surrounded by a Radio Quiet Zone (RQZ), which is it was set up using public or state laws. A Radio Quiet Zone normally consists of two areas: an exclusive area in which totally radio emissions are forbidden, with restrictions for residents and business developments, and a larger (radius up to 100 km above) coordination area where the power of radio transmission limits to threshold levels. Geographical Information System (GIS) can be used as a powerful tool in mapping large areas with varying RQZ profiles. In this paper, we report the initial testing of the usage of this system in order to identify the areas were suitable for Radio Quiet Zone. Among the important parameters used to develop the database for our GIS are population density, information on TV and telecommunication (mobile phones) transmitters, road networks (highway), and contour shielding. We will also use other information gathered from on-site RFI level measurements on selected 'best' areas generated by the GIS. The intention is to find the best site for the purpose of establishing first radio quiet zones for radio telescope in Malaysia.

Umar, Roslan; Abidin, Zamri Zainal; Ibrahim, Zainol Abidin

2013-05-01

109

An outside view of Radio Astronomy  

NASA Astrophysics Data System (ADS)

Astronomy is in a golden age of discovery of the new, with a growing appreciation from astrophysics that physics has studied so far an almost insignificant fraction of reality. This golden age is enabled by technology, with next generation technologies approaching the Giga-euro/dollar investment level. This forces a strategic view of relative strengths in the past, and strategies for future developments. Some of these may transcend traditional wavelength classifications.

Gilmore, G.

110

SparseRI: A Compressed Sensing Framework for Aperture Synthesis Imaging in Radio Astronomy  

E-print Network

Department of Physics and Astronomy, University of New Mexico, Albuquerque, NM 87131, USA 4 National RadioSparseRI: A Compressed Sensing Framework for Aperture Synthesis Imaging in Radio Astronomy S Astronomy Observatory, Socorro, NM 87801, USA #12;­ 2 ­ itself to be reconstructed. Since the size

Magnor, Marcus

111

Journal of Astronomical History and Heritage, 12(3), 249-253 (2009). THE IAU HISTORIC RADIO ASTRONOMY WORKING GROUP.  

E-print Network

astronomers who are active in the history of radio astronomy field or sympathetic to it. 2 National initiative of Commissions 40 (Radio Astronomy) and 41 (History of Astronomy), in order to: · assemble of these instruments; · maintain an on-going bibliography of public- cations on the history of radio astronomy

Groppi, Christopher

112

Multielement system design in astronomy and radio science  

NASA Astrophysics Data System (ADS)

This book deals with multielement systems representing a set of interdependent identical elements of a comparatively small size. Such systems are widely used in various fields of astronomy and radio science, their classical examples being radio telescopes, optical and radio interferometers, orbital X-ray and gamma-ray telescopes, and phased antenna arrays for radio communication and radar facilities. Here the problems of the optimal arrangement of elements of such systems are investigated to provide their high-performance characteristics such as resolution, sensitivity, and robustness to the statistically inhomogeneous propagation medium. The distinctive feature of the book is the use of the combinatorial approach to system optimization that proves especially useful for systems with a very large number of elements. The book is addressed to research physicists and engineers who are concerned with the development of astronomical instruments and large antenna arrays, and to graduate students learning about these subjects.

Kopilovich, Lazarus E.; Sodin, Leonid G.

113

Voyager planetary radio astronomy at Neptune  

Microsoft Academic Search

Detection of very intense short radio bursts from Neptune was possible as early as 30 days before closest approach and at least 22 days after closest approach. The bursts lay at frequencies in the range 100 to 1300 kilohertz, were narrowband and strongly polarized, and presumably originated in southern polar regions of the planet. Episodes of smooth emissions in the

James W. Warwick; David R. Evans; Gerard R. Peltzer; Robert G. Peltzer; Joseph H. Romig; Constance B. Sawyer; Anthony C. Riddle; Andrea E. Schweitzer; Michael D. Desch; Michael L. Kaiser; W. M. Farrell; T. D. Carr; I. de Pater; D. H. Staelin; S. Gulkis; R. L. Poynter; A. Boischot; F. Genova; Y. Leblanc; A. Lecacheux; B. M. Pedersen; P. Zarka

1989-01-01

114

Radio broadcasting: an attractive way of broadcasting astronomy  

NASA Astrophysics Data System (ADS)

Astronomy is full of beautiful skyscapes, shining stars and huge planets. The vast majority of them can be transformed into tactile images and complemented by audio descriptions. These translations of visual information into raised lines, shapes and textures can be felt with the fingertips instead of viewed with the eyes. In this way, the beauties of the Universe enter the universe of blind and visually impaired people. Happily, we all have radio broadcasting as an important source of information and entertainment. Science radio programmes can bring the real music of the spheres (as Pythagoras once suggested) to the audience.

Mosoia, C.

2008-06-01

115

Correlating Radio Astronomy Signals with Many-Core Hardware  

Microsoft Academic Search

A recent development in radio astronomy is to replace traditional dishes with many small antennas. The signals are combined\\u000a to form one large, virtual telescope. The enormous data streams are cross-correlated to filter out noise. This is especially\\u000a challenging, since the computational demands grow quadratically with the number of data streams. Moreover, the correlator\\u000a is not only computationally intensive, but

Rob V. van Nieuwpoort; John W. Romein

2011-01-01

116

A New Approach to Interference Excision in Radio Astronomy: Real-Time Adaptive Cancellation  

Microsoft Academic Search

Every year, an increasing amount of radio-frequency (RF) spectrum in the VHF, UHF, and microwave bands is being utilized to support new commercial and military ventures, and all have the potential to interfere with radio astronomy observations. Such services already cause problems for radio astronomy even in very remote observing sites, and the potential for this form of light pollution

Cecilia Barnbaum; Richard F. Bradley

1998-01-01

117

Phenomenology of Neptune's radio emissions observed by the Voyager planetary radio astronomy experiment  

NASA Technical Reports Server (NTRS)

The Neptune flyby in 1989 added a new planet to the known number of magnetized planets generating nonthermal radio emissions. We review the Neptunian radio emission morphology as observed by the planetary radio astronomy experiment on board Voyager 2 during a few weeks before and after closest approach. We present the characteristics of the two observed recurrent main components of the Neptunian kilometric radiation, i.e., the 'smooth' and the 'bursty' emissions, and we describe the many specific features of the radio spectrum during closest approach.

Pedersen, B. M.; Lecacheux, A.; Zarka, P.; Aubier, M. G.; Kaiser, M. L.; Desch, M. D.

1992-01-01

118

Teaching Astronomy at Columbus State University using Small Radio Telescopes  

NASA Astrophysics Data System (ADS)

Astronomy is inherently fascinating to students but dark skies and good weather are not often scheduled during the school day. Radio telescopes provide an all-weather, all-day opportunity for astronomical observations. Columbus State University (CSU) has installed two Small Radio Telescopes for use by undergraduate students to pursue extra-curricular research in introductory astronomy. These telescopes are relatively affordable and are designed to be remotely operated through a Windows, Linux, or Macintosh environment. They are capable of diffraction-limited observations of the Sun and galactic Hydrogen in the L-band. A comprehensive website of projects suitable for high-school students and undergraduates is maintained by a group at MIT. This website ensures users are not left to explore the telescopes abilities blindly. Students with varied interests learn about the nature of science by using an instrument that doesnt lend itself to pretty pictures. Radio telescopes also provide a slight engineering flavor drawing in students who might not otherwise be interested in astronomy. This poster will provide a summary of installation, calibration, and future plans, and will share some observations by undergraduates at CSU.

Webster, Zodiac T.

2006-12-01

119

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under a cooperative agreement by Associated Universities, Inc. Astronomy: The Visible and Invisible Universe  

E-print Network

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated Universe #12;The National Radio Astronomy Observatory is a facility of the National Science Foundation, no matter how long... #12;The National Radio Astronomy Observatory is a facility of the National Science

Groppi, Christopher

120

Planetary radio astronomy: Earth, giant planets, and beyond  

NASA Astrophysics Data System (ADS)

The magnetospheric phenomenon of non-thermal radio emission is known since the serendipitous discovery of Jupiter as radio planet in 1955, opening the new field of "Planetary Radio Astronomy". Continuous ground-based observations and, in particular, space-borne measurements have meanwhile produced a comprehensive picture of a fascinating research area. Space missions as the Voyagers to the Giant Planets, specifically Voyager 2 further to Uranus and Neptune, Galileo orbiting Jupiter, and now Cassini in orbit around Saturn since July 2004, provide a huge amount of radio data, well embedded in other experiments monitoring space plasmas and magnetic fields. The present paper as a condensation of a presentation at the Kleinheubacher Tagung 2013 in honour of the 100th anniversary of Prof. Karl Rawer, provides an introduction into the generation mechanism of non-thermal planetary radio waves and highlights some new features of planetary radio emission detected in the recent past. As one of the most sophisticated spacecraft, Cassini, now in space for more than 16 years and still in excellent health, enabled for the first time a seasonal overview of the magnetospheric variations and their implications for the generation of radio emission. Presently most puzzling is the seasonally variable rotational modulation of Saturn kilometric radio emission (SKR) as seen by Cassini, compared with early Voyager observations. The cyclotron maser instability is the fundamental mechanism under which generation and sufficient amplification of non-thermal radio emission is most likely. Considering these physical processes, further theoretical investigations have been started to investigate the conditions and possibilities of non-thermal radio emission from exoplanets, from potential radio planets in extrasolar systems.

Rucker, H. O.; Panchenko, M.; Weber, C.

2014-11-01

121

Reflections on the Radio Astronomy Explorer program of the 1960s and 70s  

NASA Technical Reports Server (NTRS)

The Radio Astronomy Explorer (RAE) program of the late 1960s and early 1970s is, to date, the only totally dedicated radio astronomy mission to have flown. However, only some of the prelaunch goals were achieved due to the unexpectedly high levels of interference from the earth in the form of both naturally occurring and man-made noise. Some important lessons in receiver design were learned which could and should be applied to any future radio astronomy missions.

Kaiser, M. L.

1990-01-01

122

The large synthesis radio telescopes of the National Radio Astronomy Observatory  

Microsoft Academic Search

It is noted that large radio telescope arrays such as the Very Large Array and Very Long Baseline Array at the National Radio Astronomy Observatory challenge the state of the art of microwave technology in many areas. Examples include the design of optimized sparse arrays and the design and the economic construction of high-performance, frequency-flexible antennas, reliable low-noise receivers, and

P. J. Napier

1992-01-01

123

Radio Astronomy in Malaysia: Current Status and Outreach Activities  

NASA Astrophysics Data System (ADS)

In this paper, we will present the current status of radio astronomical research and outreach in Malaysia. We will also present a short history of our research group, which is currently the only radio astronomical facility in Malaysia. Our group is called the Radio Cosmology Research Lab and was established in 2005 by Dr Zamri Zainal Abidin and Prof Dr Zainol Abidin Ibrahim. We will discuss the future plans for this group including our keen interest in being part of a more global network of radio astronomers. We are already an active member of the South-East Asia Astronomy Network (SEAAN) and aims to have a radio astronomical facility in order to join the Global Very Long Baseline Interferometer (VLBI) as well becoming a research hub for the future Square Kilometer Array (SKA) project. We will also present some of the scientific goals of our group including providing a platform for radio astronomers to be able to do observations of weak and high red-shifted radio objects such as galaxy clusters and supernovae.

Hashim, N.; Abidin, Z. Z.; Ibrahim, U. F. S. U.; Umar, R.; Hassan, M. S. R.; Rosli, Z.; Hamidi, Z. S.; Ibrahim, Z. A.

2011-12-01

124

Journal of Astronomical History and Heritage, 15(3), 255-257 (2012). IAU HISTORIC RADIO ASTRONOMY WORKING GROUP  

E-print Network

site. In 2003, the National Radio Astronomy Observa- tory initiated the first Archives devoted of publications on the history of radio astronomy; and d) monitor other develop- ments relating to the history of radio astronomy (in- cluding the deaths of pioneering radio astronomers). The HRA WG is now an Inter

Groppi, Christopher

125

Acousto-optic spectrometer for radio astronomy  

NASA Technical Reports Server (NTRS)

Recent developments in acousto-optic techniques and in photodetector arrays have made feasible a new type of RF spectrometer, offering the advantages of wide bandwidth, high resolution, large number of channels in compact, lightweight, energy efficient, and relatively low cost systems. Such a system employs an acousto-optic diffraction cell which serves the key role of converting RF signals to ultrasonic traveling-waves modulating the optical index of the cell. The cell is illuminated across its aperture by a monochromatic laser beam. A fraction of the light is diffracted by the acoustic waves. A focusing lens follows the cell and essentially performs a Fourier transform of the RF signal into a far-field intensity pattern. CSIRO in Australia and the Tokyo Astronomical Observatory in Japan have taken the lead in using acousto-optic techniques in astronomical applications. The first practical device was successfully made at CSIRO for obtaining dynamical spectrographs of solar radio emission.

Chin, G.; Buhl, D.; Florez, J. M.

1980-01-01

126

RASDR: Benchtop Demonstration of SDR for Radio Astronomy  

SciTech Connect

The Society of Amateur Radio Astronomers (SARA) members present the benchtop version of RASDR, a Software Defined Radio (SDR) that is optimized for Radio Astronomy. RASDR has the potential to be a common digital receiver interface useful to many SARA members. This document describes the RASDR 0.0 , which provides digitized radio data to a backend computer through a USB 2.0 interface. A primary component of RASDR is the Lime Microsystems Femtocell chip which tunes from a 0.4-4 GHz center frequency with several selectable bandwidths from 0.75 MHz to 14 MHz. A second component is a board with a Complex Programmable Logic Device (CPLD) chip that connects to the Femtocell and provides two USB connections to the backend computer. A third component is an analog balanced mixer up conversion section. Together these three components enable RASDR to tune from 0.015 MHz thru 3.8GHz of the radio frequency (RF) spectrum. We will demonstrate and discuss capabilities of the breadboard system and SARA members will be able to operate the unit hands-on throughout the workshop.

Vacaliuc, Bogdan [ORNL] [ORNL; Oxley, Paul [Retired] [Retired; Fields, David [ORNL] [ORNL; Kurtz, Dr. Stan [Universidad Nacional Autonoma de Mexico (UNAM)] [Universidad Nacional Autonoma de Mexico (UNAM); Leech, Marcus [Shirleys Bay Radio Astronomy Consortium] [Shirleys Bay Radio Astronomy Consortium

2012-01-01

127

NATIONAL RADIO ASTRONOMY OBSERVATORY P.O. BOX 2, GREEN BANK, WV 24944  

E-print Network

NATIONAL RADIO ASTRONOMY OBSERVATORY P.O. BOX 2, GREEN BANK, WV 24944 PHONE: 304-456-2209 FAX: 304-456-2200 EMAIL: sheather@nrao.edu The National Radio Astronomy Observatory is a facility of the National Science, Observatory staff have developed an easy way for you to tell your community about your visit to the NRAO . It

Groppi, Christopher

128

Journal of Astronomical History and Heritage, 8(1), 65-69 (2005). THE IAU HISTORIC RADIO ASTRONOMY WORKING GROUP.  

E-print Network

. Recollections of "Tucson Oper- ations". The Millimeter-Wave Observatory of the National Radio Astronomy was formed at the 2003 General Assembly of the IAU as a joint initiative of Commissions 40 (Radio Astronomy of publications on the history of radio astronomy; and · monitor other developments relating to the history

Groppi, Christopher

129

Journal of Astronomical History and Heritage, 7: 53-56 (2004) The IAU Historic Radio Astronomy Working Group.  

E-print Network

Kellermann National Radio Astronomy Observatory, 520 Edgemont Rd., Charlotteville, VA 22903-2475, U.S.A. EJournal of Astronomical History and Heritage, 7: 53-56 (2004) The IAU Historic Radio Astronomy of publications on the history of radio astronomy; (4) monitoring other developments relating to the history

Groppi, Christopher

130

Federal Communications Commission US311 Radio astronomy observations may be made in the bands 13501400 MHz and 49504990 MHz  

E-print Network

and between longitudes 65° 10' W and 68° 00' W. National Radio Astronomy Observatory, Socorro, New Mexico. National Radio Astronomy Observatory, Green Bank, West Virginia Rectangle between latitudes 37° 30' N: National Radio Astronomy Observatory, Very Long Baseline Array Stations Latitude (North) Longitude (West

Bower, Geoffrey

131

Stellar Radio Astronomy. Probing Stellar Atmospheres from Protostars to Giants  

E-print Network

Radio astronomy has provided evidence for the presence of ionized atmospheres around almost all classes of non-degenerate stars. Magnetically confined coronae dominate in the cool half of the Hertzsprung-Russell diagram. Their radio emission is predominantly of non-thermal origin and has been identified as gyrosynchrotron radiation from mildly relativistic electrons, apart from some coherent emission mechanisms. Ionized winds are found in hot stars and in red giants. They are detected through their thermal, optically thick radiation, but synchrotron emission has been found in many systems as well. The latter is emitted presumably by shock-accelerated electrons in weak magnetic fields in the outer wind regions. Radio emission is also frequently detected in pre-main sequence stars and protostars, and has recently been discovered in brown dwarfs. This review summarizes the radio view of the atmospheres of non-degenerate stars, focusing on energy release physics in cool coronal stars, wind phenomenology in hot stars and cool giants, and emission observed from young and forming stars.

Manuel Guedel

2002-07-03

132

Molecules in Space: A Chemistry lab using Radio Astronomy  

NASA Astrophysics Data System (ADS)

We present the results of a laboratory exercise developed with the support of the NSF Research Experiences for Teachers program at MIT Haystack Observatory. The exercise takes the students beyond the traditional test tubes of a chemistry laboratory into the interstellar medium, where the same principles that they study about in the classroom are found to hold. It also utilizes the true multi-disciplinary nature of radio astronomy and allows the students to realize how much can be learnt by studying the universe at various wavelengths. The astronomical chemistry laboratory is presented wherein students from Chelmsford High School in Massachusetts operate the 37-m telescope at Haystack Observatory via the internet to observe radio signals from galactic chemicals. The laboratory is designed to be the means by which students witness physical evidence for molecular and orbital shapes by observing the radio emission from rotating dipoles. The laboratory described is a lynch pin activity for an integrated unit that moves from the valance shell electron configurations through molecular and orbital geometry to an understanding that many physical and chemical properties of chemicals are ultimately dependent upon the shape/geometry and consequently, dipole of the molecule. Students are expected to interpret and evaluate the nature of molecular dipoles and account for the diversity of rotational spectra using their conceptual knowledge of bonding orbital theory and their knowledge of the electronic atom. Flexibility in the lab allows students to identify individual chemicals by cross referencing radio emission from the galactic sources they have chosen against a prepared catalogue listing or by choosing to "listen" for specific chemicals at exact frequencies. A teacher resource manual containing information and data on a variety of daytime galactic source and individual chemical flux densities of molecular candidates has been prepared. Collaborative exercises and activities, and associated unit topics have also been developed.

Lekberg, M. J.; Pratap, P.

2000-12-01

133

Gordon James Stanley and the Early Development of Radio Astronomy in Australia and the United States  

NASA Astrophysics Data System (ADS)

Following the end of the Second World War, the CSIRO Radiophysics Laboratory applied the expertise and surplus radar equipment acquired during the war to problems of astronomy. Gordon Stanley was among the first group of scientists and engineers to work in the exciting new field of radio astronomy. Like many of his contemporaries, he had a strong background in radio and electronics but none in astronomy. At the Radiophysics Laboratory, and later at Caltech, Stanley developed innovative new radio telescopes and sophisticated instrumentation which resulted in important new discoveries that changed, in a fundamental way, our understanding of the Universe. He was one of those who played a key role in the early development of radio astronomy both in Australia and the United States.

Kellermann, Ken I.; Orchiston, Wayne; Slee, Bruce

134

South African SKA Project Postgraduate Scholarship Programme Postgraduate Projects for 2013 1. Radio Astronomy Science  

E-print Network

or equivalent. Knowledge and interest in theoretical astrophysics, cosmology, electrodynamics and radiation of radio halos in galaxy clusters is still unknown and is one of the hot topics in radio astronomy today with the MSc or equivalent. Knowledge and interest in theoretical astrophysics, cosmology, electrodynamics

Jarrett, Thomas H.

135

The Telescope Program for the National Radio Astronomy Observatory at Green Bank, West Virginia  

Microsoft Academic Search

A brief account is given of the initiation of the feasibility study on the establishment and operation of the National Radio Astronomy Observatory at Green Bank, West Virginia. The principal research facilities will be the radio telescopes, and a series of such telescopes have been proposed. The desired performance characteristics are reviewed. A 140-foot steerable paraboloid on an equatorial mount

R. M. Emberson; N. L. Ashton

1958-01-01

136

Radio astronomy image enhancement in the presence of phase errors using genetic algorithms  

Microsoft Academic Search

Modern radio astronomy interferometric telescopes use Earth rotation aperture synthesis imaging techniques. New projects for radio telescopes include hundreds and thousands of elements and presume multibeam and snapshot imaging. Each element, or base station, in its turn is a phase-array antenna. Phase instabilities due to instrumentation and atmospheric phase variations can ruin the synthesized image. There is a need to

Peter Fridman

2001-01-01

137

Adventures in Radio Astronomy Instrumentation and Signal Processing  

E-print Network

using radio telescopes. Modern radio telescopes have significant digital signal processing demands of spectrometers for enabling improved pulsar2 sci- ence on the Allen Telescope Array, the Hartebeesthoek Radio Observatory telescope, the Nan¸cay Radio Telescope, and the Parkes Radio Telescope. We also present work

Masci, Frank

138

Adventures in Radio Astronomy Instrumentation and Signal Processing  

E-print Network

- tizing and processing analogue astronomical signals collected using radio telescopes. Modern radio pulsar2 sci- ence on the Allen Telescope Array, the Hartebeesthoek Radio Observatory telescope, the Nan¸cay Radio Telescope, and the Parkes Radio Telescope. We also present work that we conducted

California at Berkeley, University of

139

Infrared Submillimeter and Radio Astronomy Research and Analysis Program  

NASA Technical Reports Server (NTRS)

This program entitled "Infrared Submillimeter and Radio Astronomy Research and Analysis Program" with NASA-Ames Research Center (ARC) was proposed by the Smithsonian Astrophysical Observatory (SAO) to cover three years. Due to funding constraints only the first year installment of $18,436 was funded, but this funding was spread out over two years to try to maximize the benefit to the program. During the tenure of this contact, the investigators at the SAO, Drs. Wesley A. Traub and Nathaniel P. Carleton, worked with the investigators at ARC, Drs. Jesse Bregman and Fred Wittebom, on the following three main areas: 1. Rapid scanning SAO and ARC collaborated on purchasing and constructing a Rapid Scan Platform for the delay arm of the Infrared-Optical Telescope Array (IOTA) interferometer on Mt. Hopkins, Arizona. The Rapid Scan Platform was tested and improved by the addition of stiffening plates which eliminated a very small but noticeable bending of the metal platform at the micro-meter level. 2. Star tracking Bregman and Wittebom conducted a study of the IOTA CCD-based star tracker system, by constructing a device to simulate star motion having a specified frequency and amplitude of motion, and by examining the response of the tracker to this simulated star input. 3. Fringe tracking. ARC, and in particular Dr. Robert Mah, developed a fringe-packet tracking algorithm, based on data that Bregman and Witteborn obtained on IOTA. The algorithm was tested in the laboratory at ARC, and found to work well for both strong and weak fringes.

Traub, Wesley A.

2000-01-01

140

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. January 1, 2010  

E-print Network

The National Radio Astronomy Observatory is a facility of the National Science Foundation Opportunity Non-Discrimination and Harassment Statement The National Radio Astronomy Observatory is committed discriminatory practices, including sexual harassment. The Observatory will take affirmative action to ensure

Groppi, Christopher

141

Surfing Long Waves of the Universe... ...The National Radio Astronomy Observatory in the 21st Century  

Microsoft Academic Search

IN 2006, the National Radio Astronomy Observatory (NRAO) passed the 50-year point in its service to the astronomical community\\u000a and now looks forward to an exciting future as one of the worlds premier resources for answering the key questions that challenge\\u000a 21st-century astronomy and physics. Todays world-class suite of NRAO telescopes provides unique and powerful capabilities\\u000a for frontier research. Combined

David Finley

142

Investigation on the Frequency Allocation for Radio Astronomy at the L Band  

NASA Astrophysics Data System (ADS)

In this paper, the frequency allocation reserved for radio astronomy in the L band set by the International Telecommunication Union (ITU), which is between 1400 and 1427 MHz, is reviewed. We argue that the nearby frequencies are still very important for radio astronomers on the ground by investigating radio objects (H i sources) around 1300-1500 MHz. The L-band window is separated into a group of four windows, namely 1400-1427 MHz (window A), 1380-1400 MHz (window B), 1350-1380 MHz (window C), and 1300-1350 MHz (window D). These windows are selected according to their redshifts from a rest frequency for hydrogen spectral line at 1420.4057 MHz. Radio objects up to z ? 0.1 or frequency down to 1300 MHz are examined. We argue that since window B has important radio objects within the four windows, this window should also be given to radio astronomy. They are galaxies, spiral galaxies, and galaxy clusters. This underlines the significance of window B for radio astronomers on the ground. By investigating the severeness of radio frequency interference (RFI) within these windows, we have determined that window B still has significant, consistent RFI. The main RFI sources in the four windows have also been identified. We also found that the Department of Civil Aviation of Malaysia is assigned a frequency range of 1215-1427 MHz, which is transmitted within the four windows and inside the protected frequency for radio astronomy. We also investigated the RFI in the four windows on proposed sites of future radio astronomy observatories in Malaysia and Thailand and found the two best sites as Universiti Pendidikan Sultan Idris (UPSI) and Ubon Ratchathani, respectively. It has also been determined that RFI in window B increases with population density.

Abidin, Z. Z.; Umar, R.; Ibrahim, Z. A.; Rosli, Z.; Asanok, K.; Gasiprong, N.

2013-09-01

143

A Sustainable approach to large ICT Science based infrastructures; the case for Radio Astronomy  

E-print Network

Large sensor-based infrastructures for radio astronomy will be among the most intensive data-driven projects in the world, facing very high power demands. The geographically wide distribution of these infrastructures and their associated processing High Performance Computing (HPC) facilities require Green Information and Communications Technologies (ICT). A combination is needed of low power computing, efficient data storage, local data services, Smart Grid power management, and inclusion of Renewable Energies. Here we outline the major characteristics and innovation approaches to address power efficiency and long-term power sustainability for radio astronomy projects, focusing on Green ICT for science.

Barbosa, Domingos; Boonstra, Albert-Jan; Aguiar, Rui; van Ardenne, Arnold; de Santander-Vela, Juande; Verdes-Montenegro, Lourdes

2014-01-01

144

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. January 1, 2010  

E-print Network

The National Radio Astronomy Observatory is a facility of the National Science Foundation Plan Veteran Non-Discrimination Statement It is the policy of the National Radio Astronomy Observatory. Furthermore, the National Radio Astronomy Observatory will solicit the cooperation and support of all

Groppi, Christopher

145

The NRAO Green Bank Site is a unique resource for Radio Astronomy. We are located in the National Radio Quiet Zone (NRQZ) which provides protection from permanent, fixed, licensed transmitter services. Our location,  

E-print Network

· National Radio Astronomy Observatory Continuted on back #12;In Zone 1, the "ground zero" of our instrumentsThe NRAO Green Bank Site is a unique resource for Radio Astronomy. We are located in the National to protect observations. Additionally, the West Virginia Radio Astronomy Zoning Act allows us to prohibit

Groppi, Christopher

146

Voyager 1 planetary radio astronomy observations near Jupiter  

Microsoft Academic Search

Results are reported from the first low frequency radio receiver to be transported into the Jupiter magnetosphere. Dramatic new information was obtained both because Voyager was near or in Jupiter's radio emission sources and also because it was outside the relatively dense solar wind plasma of the inner solar system. Extensive radio arcs, from above 30 MHz to about 1

J. W. Warwick; J. B. Pearce; A. C. Riddle; J. K. Alexander; M. D. Desch; M. L. Kaiser; J. R. Thieman; T. B. Carr; S. Gulkis; A. Boischot; C. C. Harvey; B. M. Pedersen

1979-01-01

147

A Low-Frequency Distributed Aperture Array for Radio Astronomy in Space  

Microsoft Academic Search

The frequency band below 30 MHz is one of the last unexplored bands in radio astronomy. This band is well suited for studying the early cosmos at high hydrogen redshifts, the so-called dark ages, extragalactic surveys, (extra) solar planetary bursts, and high energy particle physics. In addition, space research such as space weather tomography, are also areas of scientific interest.

Albert-Jan Boonstra; Noah Saks; Heino Falcke; Marc Klein-Wolt; Ark Bentum; Raj Thilak Rajan; Ir. Stefan J. Wijnholds; Michel Arts; Kees van-T Klooster; Frederik Belien

2010-01-01

148

Tectonic motion site survey of the National Radio Astronomy Observatory, Green Bank, West Virginia  

Microsoft Academic Search

A geological and geophysical site survey was made of the area around the National Radio Astronomy Observatory (NRAO) to determine whether there are at present local tectonic movements that could introduce significant errors to Very Long Baseline Interferometry (VLBI) geodetic measurements. The site survey consisted of a literature search, photogeologic mapping with Landsat and Skylab photographs, a field reconnaissance, and

W. J. Webster Jr.; R. J. Allenby; L. K. Hutton; P. D. Lowman Jr.; H. A. Tiedemann

1979-01-01

149

Outer planets grand tours: Planetary radio astronomy team report  

NASA Technical Reports Server (NTRS)

Requirements related to scientific observations of planetary radio emissions during outer planets grand tours are discussed. Observations at low frequencies where non-thermal cooperative plasma phenomena play a major role are considered for determining dynamical processes and magnetic fields near a planet. Magnetic field measurements by spacecraft magnetometers, and by radio receivers in their harmonic modes are proposed for interpretation of planetary radio emission.

Warwick, J. W.

1972-01-01

150

The birthplace of planetary radio astronomy: The Seneca, Maryland observatory 50 years after Burke and Franklin's Jupiter radio emission discovery.  

NASA Astrophysics Data System (ADS)

Burke and Franklin's discovery of radio emissions from Jupiter in 1955 effectively marked the birth of the field of planetary radio astronomy. The discovery was made near Seneca, Maryland using the Department of Terrestrial Magnetism/Carnegie Institution of Washington's Mills Cross Array. Fifty years later there is very little evidence of this 96-acre X-shaped array of dipoles still in existence, nor evidence of any of the other antennas used at this site. The site, now known as the McKee Besher Wildlife Management Area, is owned by the State of Maryland Department of Natural Resources. Radio Jove, a NASA/GSFC education and public outreach project, will recognize the 50th anniversary of this discovery through an historic reenactment using their receiver and dual-dipole array system. Our search through the DTM/CIW archives, our visit to the site to look for evidence of this array, and other efforts at commemorating this anniversary will be described.

Garcia, L. N.; Thieman, J. R.; Higgins, C. A.

2004-12-01

151

Radio Astronomy at the Centre for High Performance Computing in South Africa  

NASA Astrophysics Data System (ADS)

I will present results on galaxy evolution and cosmology which we obtained using the supercomputing facilities at the CHPC. These include cosmological-scale N-body simulations modelling neutral hydrogen as well as the study of the clustering of radio galaxies to probe the relationship between dark and luminous matter in the universe. I will also discuss the various roles that the CHPC is playing in Astronomy in SA, including the provision of HPC for a variety of Astronomical applications, the provision of storage for radio data, our educational programs and our participation in planning for the SKA.

Catherine Cress; UWC Simulation Team

2014-04-01

152

The Evolution of the National Radio Astronomy Observatory into a User Based Observatory  

Microsoft Academic Search

The NRAO was conceived in the mid 1950s as a state-of-the-art facility to allow the United States to compete in the exciting radio astronomy discoveries then taking place in the U.K., the Netherlands and Australia. Otto Struve, the first NRAO director in Green Bank, was chosen to lead the Observatory research program. During Struve's tenure as director, nearly all of

Kenneth I. Kellerman; E. Bouton

2006-01-01

153

Molecular Clouds in the Boston University--Five College Radio Astronomy Observatory Galactic Ring Survey  

Microsoft Academic Search

The Boston University--Five College Radio Astronomy Observatory (BU-FCRAO) Galactic Ring Survey (GRS) is a new survey of 13CO (1--0) emission covering Galactic longitudes 18 deg < l < 55.7 deg and Galactic latitudes |b| < 1 deg. Using the SEQUOIA array on the FCRAO 14m telescope, the GRS fully sampled the 13CO Galactic emission (46 arcsec angular resolution on a

A. M. Johnson; J. M. Rathborne; J. M. Jackson; R. Y. Shah; R. Simon

2005-01-01

154

Reference antenna-based subspace tracking for RFI mitigation in radio astronomy  

NASA Astrophysics Data System (ADS)

Interference mitigation is becoming necessary to make radio astronomy work in bands that are heavily used to support our modern lives. It is becoming particularly difficult to work at frequencies between 1100 MHz and 1300 MHz that are rapidly filling up with satellite navigation signals. Antenna array radio telescopes present the possibility of applying spatial Radio Frequency Interference (RFI) mitigation. Spatial filtering techniques for RFI mitigation have been introduced to radio astronomy in the last decades. The success of these techniques relies on accurately estimating the RFI spatial signature (or RFI subspace). The use of a reference antenna steering at the RFI sources provides a good estimation of the RFI subspace when correlated with an array radio telescope. However, predicting the evolution of this subspace with time is necessary in a multiple RFI scenario, when only a single RFI source can be monitored at a time with the reference antenna. This paper introduces a subspace tracking approach, based on the power method applied to covariance data. The RFI spatial signature estimates provided by the reference antenna are used to initialize the power method to support a faster convergence. Practical examples are shown, applying the method to real data from a single 188 element phased array feed designed for the Australian Square Kilometre Array Pathfinder (ASKAP) telescope.

Hellbourg, G.; Chippendale, A. P.; Kesteven, M. J.; Jeffs, B. D.

2014-12-01

155

Electronic Multi-beam Radio Astronomy Concept: Embrace a Demonstrator for the European SKA Program  

NASA Astrophysics Data System (ADS)

ASTRON has demonstrated the capabilities of a 4 m2, dense phased array antenna (Bij de Vaate et al., 2002) for radio astronomy, as part of the Thousand Element Array project (ThEA). Although it proved the principle, a definitive answer related to the viability of the dense phased array approach for the SKA could not be given, due to the limited collecting area of the array considered. A larger demonstrator has therefore been defined, known as Electronic Multi-Beam Radio Astronomy Concept, EMBRACE, which will have an area of 625 m2, operate in the band 0.4 1.550 GHz and have at least two independent and steerable beams. With this collecting area EMBRACE can function as a radio astronomy instrument whose sensitivity is comparable to that of a 25-m diameter dish. The collecting area also represents a significant percentage area (10%) of an individual SKA station. This paper presents the plans for the realisation of the EMBRACE demonstrator.

Ardenne, A.; Wilkinson, P. N.; Patel, P. D.; Vaate, J. G. Bij

2004-06-01

156

Astronomy  

NSDL National Science Digital Library

This page contains links to one pagers on historical instruments of astronomy with photos of the following : Astronomy Slides, Celestial Globe, Cometarium, Globe, Gregorian Telescope, Kepler's Laws Demonstration, Orrery, Planetarium, Planisphere, Stereoscopic Pictures of the Moon, Tellurian, and Transit.

2000-01-01

157

Applications of Microwave Photonics in Radio Astronomy and Space Communication  

NASA Technical Reports Server (NTRS)

An overview of narrow band vs wide band signals is given. Topics discussed included signal transmission, reference distribution and photonic antenna metrology. Examples of VLA, ALMA, ATA and DSN arrays are given. . Arrays of small antennas have become more cost-effective than large antennas for achieving large total aperture or gain, both for astronomy and for communication. It is concluded that emerging applications involving arrays of many antennas require low-cost optical communication of both wide bandwidth and narrow bandwidth; development of round-trip correction schemes enables timing precision; and free-space laser beams with microwave modulation allow structural metrology with approx 100 micrometer precision over distances of 200 meters.

D'Addario, Larry R.; Shillue, William P.

2006-01-01

158

A very low frequency radio astronomy observatory on the Moon  

NASA Technical Reports Server (NTRS)

Because of terrestrial ionospheric absorption, very little is known of the radio sky beyond 10 m wavelength. An extremely simple, low cost very low frequency radio telescope is proposed, consisting of a large array of short wires laid on the lunar surface, each wire equipped with an amplifier and a digitizer, and connected to a common computer. The telescope could do simultaneous multifrequency observations of much of the visible sky with high resolution in the 10 to 100 m wavelength range, and with lower resolution in the 100 to 1000 m range. It would explore structure and spectra of galactic and extragalactic point sources, objects, and clouds, and would produce detailed quasi-three-dimensional mapping of interstellar matter within several thousand parsecs of the Sun.

Douglas, James N.; Smith, Harlan J.

1988-01-01

159

Scalable desktop visualisation of very large radio astronomy data cubes  

NASA Astrophysics Data System (ADS)

Observation data from radio telescopes is typically stored in three (or higher) dimensional data cubes, the resolution, coverage and size of which continues to grow as ever larger radio telescopes come online. The Square Kilometre Array, tabled to be the largest radio telescope in the world, will generate multi-terabyte data cubes - several orders of magnitude larger than the current norm. Despite this imminent data deluge, scalable approaches to file access in Astronomical visualisation software are rare: most current software packages cannot read astronomical data cubes that do not fit into computer system memory, or else provide access only at a serious performance cost. In addition, there is little support for interactive exploration of 3D data. We describe a scalable, hierarchical approach to 3D visualisation of very large spectral data cubes to enable rapid visualisation of large data files on standard desktop hardware. Our hierarchical approach, embodied in the AstroVis prototype, aims to provide a means of viewing large datasets that do not fit into system memory. The focus is on rapid initial response: our system initially rapidly presents a reduced, coarse-grained 3D view of the data cube selected, which is gradually refined. The user may select sub-regions of the cube to be explored in more detail, or extracted for use in applications that do not support large files. We thus shift the focus from data analysis informed by narrow slices of detailed information, to analysis informed by overview information, with details on demand. Our hierarchical solution to the rendering of large data cubes reduces the overall time to complete file reading, provides user feedback during file processing and is memory efficient. This solution does not require high performance computing hardware and can be implemented on any platform supporting the OpenGL rendering library.

Perkins, Simon; Questiaux, Jacques; Finniss, Stephen; Tyler, Robin; Blyth, Sarah; Kuttel, Michelle M.

2014-07-01

160

Fast pulsars, strange stars: An opportunity in radio astronomy  

SciTech Connect

The world's data on radio pulsars is not expected to represent the underlying pulsar population because of a search bias against detection of short periods, especially below 1 ms. Yet pulsars in increasing numbers with periods right down to this limit have been discovered suggesting that there may be even shorter ones. If pulsars with periods below 1/2 ms were found, the conclusion that the confined hadronic phase of nucleons and nuclei is only metastable would be almost inescapable. The plausible ground state in that event is the deconfined phase of (3-flavor) strange-quark-matter. From the QCD energy scale this is as likely a ground state as the confined phase. We show that strange matter as the ground state is not ruled out by any known fact, and most especially not by the fact that the universe is in the confined phase. 136 refs.

Glendenning, N.K.

1990-07-15

161

Pulsars in a Box: A Radio Astronomy Exercise for Windows from PROJECT CLEA  

NASA Astrophysics Data System (ADS)

The latest astronomy laboratory exercise from PROJECT CLEA, "Radio Astronomy of Pulsars", is designed for use in introductory astronomy classes, but contains options and features that make it usable by upperclass astronomy students as well. The heart of the exercise is a simulated radio telescope, whose aperture, location, and beamwidth can be set by the instructor. It is steered by pushing buttons, but instead of seeing a star field on the field monitor,students see a projection of the sky showing, with a colored dot,where the beam is pointing. Large LED-like readouts display time and telescope coordinates. The telescope can be operated in either a tracking or transit mode. Using the telescope, students point to several pulsars suggested by the write-up (from an on-line catalog of over 500). Students can then use a multi-channel tunable receiver, with multiple oscilloscope displays, to view the incoming signal vs. time. The signal received is a combination of random receiver and background noise plus the pulsar signal (if it is in the beam) Receivers are tunable from 400 to 1400 MHz, and both the time and frequency behavior of signals can be studied. By measuring the dispersion delay at a number of different frequencies, students can determine the pulsar's distance. Data can be stored, displayed, and printed using a versatile measuring window. Though we provide a manual for a 2-3 hour lab exercise involving dispersion measures, the database and receivers can be used for a wide variety of other exercises, for instance the measurement of pulsar spin-down rates. We welcome suggestions for improvements and applications.

Marschall, L. A.; Snyder, G. A.; Good, R. F.; Hayden, M. B.; Cooper, P. R.

1996-12-01

162

NASA IDEAS EPO Support of the School of Galactic Radio Astronomy  

NASA Astrophysics Data System (ADS)

The Pisgah Astronomical Research Institute (PARI) was awarded a STScI IDEAS Program grant to develop the School of Galactic Radio Astronomy (SGRA). SGRA enhances education of science, mathematics, and technology of students in grades 8-12. The purpose of SGRA is to teach the basics of scientific inquiry, which includes methodology, critical thinking, and communication of the results. To facilitate the excitement of science and discovery, teachers and students use the PARI 4.6m ``Smiley" radio telescope via the Internet. The IDEAS grant supported the development of the science curriculum and labs that use the 4.6m radio telescope, teacher workshops, and high speed internet service necessary for remote access to the radio telescope. Partnerships with Brevard High School , Furman University, and the University of North Carolina-Asheville have proven important to the success of the program. In addition, the IDEAS grant was important in our success in acquiring grants from the foundations at Z. Smith Reynolds and Progress Energy, a AAS Small Grant, and a STScI HST/EPO award to further enhance and continue the SGRA Program. More than 100 teachers are now involved in SGRA. To increase awareness of SGRA, we have presented the program at meetings of the AAS, North Carolina Science Teachers Association, the North Carolina Science Museum, and Pisgah Forest Institute summer workshops. Our experience in writing and carrying out the program, along with the NASA components in the program, teachers' comments, and lessons learned, will be presented. We are extremely grateful to the IDEAS Grant Program for helping PARI initiate and develop an exciting program of hands-on Internet radio astronomy from high school classrooms.

Castelaz, M.; Daugherty, J.; Moffett, D.; Case, J.

2005-05-01

163

Astronomy.  

ERIC Educational Resources Information Center

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics

Greenstone, Sid; Smith, Murray

164

Tectonic motion site survey of the National Radio Astronomy Observatory, Green Bank, West Virginia  

NASA Technical Reports Server (NTRS)

A geological and geophysical site survey was made of the area around the National Radio Astronomy Observatory (NRAO) to determine whether there are at present local tectonic movements that could introduce significant errors to Very Long Baseline Interferometry (VLBI) geodetic measurements. The site survey consisted of a literature search, photogeologic mapping with Landsat and Skylab photographs, a field reconnaissance, and installation of a seismometer at the NRAO. It is concluded that local tectonic movement will not contribute significantly to VLBI errors. It is recommended that similar site surveys be made of all locations used for VLBI or laser ranging.

Webster, W. J., Jr.; Allenby, R. J.; Hutton, L. K.; Lowman, P. D., Jr.; Tiedemann, H. A.

1979-01-01

165

The impact of JPEG2000 lossy compression on the scientific quality of radio astronomy imagery  

E-print Network

The sheer volume of data anticipated to be captured by future radio telescopes, such as, The Square Kilometer Array (SKA) and its precursors present new data challenges, including the cost and technical feasibility of data transport and storage. Image and data compression are going to be important techniques to reduce the data size. We provide a quantitative analysis of the effects of JPEG2000's lossy wavelet image compression algorithm on the quality of the radio astronomy imagery data. This analysis is completed by evaluating the completeness, soundness and source parameterisation of the Duchamp source finder using compressed data. Here we found the JPEG2000 image compression has the potential to denoise image cubes, however this effect is only significant at high compression rates where the accuracy of source parameterisation is decreased.

Peters, Sean M

2014-01-01

166

Moon-based Very Long-Wavelength Radio Astronomy Facility: science drives and technological challenges  

NASA Astrophysics Data System (ADS)

Scientific laboratories at manned and un-manned Moon bases are top priorities for the next wave of exploratory missions. Environmental conditions on the Moon are beneficial for various types of experimental research. Very Long Wavelength radio Astronomy (VLWA) is among the most attractive scientific disciplines for the suit of Moon-based laboratories. Space science has revolutionised astronomy by opening up several hitherto inaccessible windows in the spectrum. The opening of each new spectral window has resulted in unexpected discoveries and made it possible to obtain a comprehensive picture of physical processes in celestial sources. One of the last remaining unexplored regions of the spectrum is at the lowest radio frequencies. Radio emission below 15 MHz (wavelengths longer than 20 m) is inaccessible from the Earth surface due to absorption and scattering in the ionosphere. Unique new science areas for VLWA studies include: (i)Investigation of radio sky at so far inaccessible regime of electromagnetic radiation; (ii) Cosmological "experiments" with "fossil" relativistic electrons; (iii) Investigation of ultra-high-energy cosmic rays via VLWA emission from particle interactions with the Moon; (iv) Solar system "weather", including coronal mass ejections, (v) Searches for Jupiter-like exoplanets. In addition to the astrophysical tasks mentioned above, the VLWA facility on the Moon can be implemented as a Wide Area Network, as pioneered by the Earth-based Low Frequency Array (LOFAR). This allows the inclusion of other sensors, such as seismic detectors to conduct selenological studies. The LOFAR is being constructed in the Netherlands. It will operate in the frequency range 20 - 220 MHz. Several other projects will aim at addressing cosmological problems by studying the Universe at the range of frequencies below 100 MHz. These and other new radio astronomy facilities will lay the scientific and technological ground for VLWA in space. We will present a multi-step approach toward creating a permanent VLWA observatory on the Moon. Its first phase would include a demonstrator to be deployed as a small-scale scientific payload onboard one of the lunar missions of the next decade. A concept of an affordable fullscale observatory will be presented in the context of a long-term Moon exploration programme.

Gurvits, Leonid

167

Research on Haystack radiometer, 20-24 GHz maser, and radio astronomy programs  

NASA Technical Reports Server (NTRS)

During the first half of 1973, the Haystack antenna was utilized 76% of the time. Of this useful time, 72% was devoted to radio astronomy observing, 5% was spent on radar-related research and 23% went into maintenance and system improvements. Twenty-eight new radio astronomy programs were accepted, eight of which were completed during the period. One new radar program, topographic observations of Mars, was started in June and will be completed early in 1974. Fourteen programs continued from the previous period were also defined as complete. As of 1 July, 28 ratio observing programs were in a continuing status on the Haystack books. Four radar projects were also continuing. The 20-24 GHz maser development described in the preceding report progressed very well during an on-antenna test phase which began early in the year, but which terminated unfortunately in June with the complete loss of gain in the maser. Investigation of this problem is in progress. During this on-antenna test phase, the most sensitive water vapor observing capability which has yet become available was demonstrated.

1973-01-01

168

DEPARTMENT OF ASTRONOMY & ASTROPHYSICS Special Astronomy Seminar  

E-print Network

DEPARTMENT OF ASTRONOMY & ASTROPHYSICS Special Astronomy Seminar October 13, 2011 Speaker : Mayukh) Abstract Black hole X-ray binaries (BHXBs) are widely observed sources in the X-ray and radio astronomy

Udgaonkar, Jayant B.

169

Background radio-frequency radiation and its impact on radio astronomy Michelle C. Storey, Bruce MacA Thomas and John M. Sarkissian  

E-print Network

. Inland Australia possesses areas that are still relatively radio-quiet compared to the rest of the world-quiet reserve exist in inland Australia. 1. Spectrum use and astronomy Recent satellite pictures have for example http://www.darksky.org/ida/images.html). This light obscures the night sky for many urban dwellers

Sarkissian, John M.

170

Terrestrial Interference Effects on Space-Based Low Frequency Radio Astronomy  

NASA Astrophysics Data System (ADS)

Radio astronomy observations in the HF (1-30 MHz) portion of the electromagnetic spectrum could result in new insights into astrophysical processes. However, this particular part of the spectrum is mostly inaccessible from the ground due to the effects of the Earth's ionosphere. One solution is to observe from Earth orbit, thereby avoiding most of the absorption and phase distortions from the ionosphere. However, in the 1-30 MHz band of interest, the ionosphere is neither a perfect reflector nor is it a perfect transmission medium. Terrestrial signals leak through and increase the background radio noise or introduce spurious signals into the measurements, making the detection of faint sources difficult. All terrestrial HF communications signals, especially over-the-horizon radar, are potential interferers to low frequency radio astronomy. Ideally, radio telescopes on the moon's far side would provide a perfectly shielded environment, but at much greater cost and difficulty than a similar system in Earth orbit. We are investigating methods of predicting signal strengths at the top of the ionosphere with respect to time, frequency, and solar behavior. Existing ionospheric models provide a description of the general, global state of the ionosphere. This information is used as an input to our ray-tracing software to predict the likelihood of leakage through the ionosphere. Sources are distributed in frequency, ray launch angles, and geographic location. Because of the ionosphere, rays can be focussed (increasing the interference intensity) or defocussed (decreasing the interference intensity). Plots of the ray paths from potential interferers, showing the focussing or defocussing effects will be presented. The collective effect of a number of widely separated interferers is to potentially increase the noise at the satellite location. The ultimate goal of this research is to determine if there exist temporal and frequency windows, where the radio leakage is on the order of the cosmic background noise, that permit high-resolution low-sensitivity radio astronomical measurements from Earth orbit. The final model should to be able to predict those times using solar and geophysical parameters.

Basart, J. P.; McCoy, M.

1994-05-01

171

Radio astronomy  

NASA Technical Reports Server (NTRS)

A K-band reflected-wave ruby maser was used on the 64-meter (DSS-43) antenna at the Tidbinbilla Tracking Station, near Canberra, Australia. Spectral line observations were carried out near 22 GHz for water vapor sources and near 24 GHz for ammonia sources. The water vapor observations were made in the direction of known southern OH and H2O maser sources. All of the previously detected water line sources examined were detected. In addition, two new water vapor maser sources were discovered, G301.1+1.1and G308.9+0.1. The spectrum of G301.0+1.1 is presented six ammonia sources were found: G291.3-0.7, G305.4+0.2, G322.2+0.6, G327.3-0.5, G333.6-0.2, and G268.4-0.8. Spectra of two of these sources, G291.3-0.7 (RCW 57) and G305.4+0.2, are presented. Both show clearly the presence of the quadrupole splitting satellite lines that will allow the determination of NH3 optical depths in these clouds.

Shaffer, R. D.; Mccluskey, J. T.; Gulkis, S.; Klein, M.; Kuiper, T.

1981-01-01

172

Matched wideband low-noise amplifiers for radio astronomy S. Weinreb, J. Bardin, H. Mani, and G. Jones  

E-print Network

Matched wideband low-noise amplifiers for radio astronomy S. Weinreb, J. Bardin, H. Mani, and G low noise amplifiers for the 0.3­4 GHz frequency range are described. The amplifiers can be operated temperature. One amplifier utilizes commercially available, plastic-packaged SiGe transistors for first

Weinreb, Sander

173

Observations of noise bands associated with the upper hybrid resonance by the Imp 6 radio astronomy experiment  

Microsoft Academic Search

The intense noise bands occurring near the upper hybrid resonanace ; frequency have been observed with the Imp 6 GSFC radio astronomy experiment in ; the plasmasphere. The identification of the upper hybrid resonance provides an ; accurate measure of the local electron density and allows the observed noise data ; to be fit to the scale of characteristic frequencies

Stephen R. Mosier; Michael L. Kaiser; L. W. Brown

1973-01-01

174

Estimate of Interference from the Aeronautical Mobile Services of the Cities of Glendale and Pasadena to Goldstone Radio Astronomy Stations at 4.9 Gigahertz  

NASA Astrophysics Data System (ADS)

The Federal Communications Commission (FCC) recently allocated the 4.9-GHz band to public safety telecommunications services. Radio Astronomy Services (RAS) also has been using this frequency. NASA will primarily use Deep Space Station 28 (DSS 28) at Goldstone, California, for radio astronomy services that are sensitive to radio-frequency interference (RFI). This study is to determine the RFI potential of airborne transmission from two cities to radio astronomy sites in Goldstone. Propagation losses over the terrain between both cities and Goldstone are estimated using the Trans-Horizon Interference Propagation Loss (THIPL) software recently developed at JPL and high-resolution terrain data. The necessary coordination area for protecting the Goldstone radio astronomy station has been defined based on the minimum propagation loss required. Study results and suggestions for modification to the airborne areas proposed by both cities' police departments are presented.

Ho, C.; Sue, M.; Manshadi, F.

2006-05-01

175

ASTRONOMY.  

ERIC Educational Resources Information Center

THIS TEACHER'S GUIDE FOR A UNIT ON ASTRONOMY ESTABLISHES (1) UNDERSTANDINGS AND ATTITUDES, (2) SKILLS, AND (3) CONCEPTS TO BE GAINED IN THE STUDY. THE OVERVIEW EXPLAINS THE ORGANIZATION AND OBJECTIVES OF THE UNIT. TOPICAL DIVISIONS ARE (1) THE EARTH, (2) THE MOON, (3) THE SUN, (4) THE SOLAR SYSTEM, (5) THE STARS, (6) THE UNIVERSE, AND (7) SPACE

Louisiana Arts and Science Center, Baton Rouge.

176

A Low-Frequency Distributed Aperture Array for Radio Astronomy in Space  

NASA Astrophysics Data System (ADS)

The frequency band below 30 MHz is one of the last unexplored bands in radio astronomy. This band is well suited for studying the early cosmos at high hydrogen redshifts, the so-called dark ages, extragalactic surveys, (extra) solar planetary bursts, and high energy particle physics. In addition, space research such as space weather tomography, are also areas of scientific interest. Due to ionospheric scintillation (below 30MHz) and its opaqueness (below 15MHz), earth-bound radio astronomy observations in these bands are either severely limited in sensitivity and spatial resolution or entirely impossible. A radio telescope in space obviously would not be hampered by the Earth's ionosphere. In the past, several (limited) studies have been conducted to explore possibilities for such an array in space. These studies considered aperture synthesis arrays in space, at the back-side of the Moon, or a satellite constellation operating in a coherent mode. In 2009 an ESA project, Distributed Aperture Array for Radio Astronomy in Space (DARIS), set out to investigate the space-based radio telescope concept. The focus of this feasibility study is on a moderate size three-dimensional satellite constellation operating as a coherent large aperture synthesis array. This aperture synthesis array would consist of 5 to 50 antennas (satellites) having a maximum separation of 100 km. This study considers the main aspects of such a distributed system in more detail than previous studies. This conference contribution aims at presenting an overview of the DARIS project and at discussing the main results. The project selected extra-galactic surveys and the search for transient radio sources as the best suited science cases within the DARIS concept, and it investigated the scientific and technical requirements for such an array. Several antenna concepts were considered and simulated. An active antenna dipole array concept would be well suited, and a moderate 5 m tip-tip antenna system would lead to a sky noise limited system. Multiple digital signal processing scenarios were considered. Ultimately, although a distributed signal processing approach would be fa-vorable in terms of reliability and scalability, for complexity reasons the project has chosen to have several (5 to 50) identical receiving nodes, and one centralized processing node i.e. the correlator. Analysis has shown that with current technologies, one MHz bandwidth can be processed with full duty cycle. The limiting factor is the inter-satellite link bandwidth. Several deployment locations, such as Moon orbit, Earth-Moon L2, and dynamic Solar orbits were investigated. Each of those locations has its pro's and con's such as interference levels from the Earth (which drive the number of sampling bits), relative speed-vectors of the satellite nodes (influencing maximum correlator integration times, and the need for orbit maintenance), and achievable down-link bandwidth to Earth. Two preferred deployment location were selected: Moon orbit and dynamic Solar orbit. The main advantage of the Moon orbit is that the syn-thetic aperture is filled more rapidly, making it more suitable for transient science than the dynamic Solar orbit. The project also studied the relation between the three-dimensional satellite configuration, the deployment location and the quality of the sky maps. The conclusion is that for the science cases under consideration, sufficient independent aperture sampling points can be obtained in a 1 MHz limited band (with 1 kHz channels) by using bandwidth synthesis. It is expected that, as a result, up to about one million astronomical sources can be detected in a five year duration mission.

Boonstra, Albert-Jan; Saks, Noah; Falcke, Heino; Klein-Wolt, Marc; Bentum, Ark; Thilak Rajan, Raj; Wijnholds, Ir. Stefan J.; Arts, Michel; van-T Klooster, Kees; Belien, Frederik

177

National Radio Astronomy Observatory: The early history and development of the observatory at Green Bank, West Virginia, are reviewed.  

PubMed

The existence of the National Radio Astronomy Observatory and the researches already accomplished there are the result of the foresight and wisdom of United States scientists, the National Science Board, and the Congress, who joined forces to make possible this new national asset. Continued effort will be needed td insure that the observatory will always have the finest possible research instruments and that the site will be a haven of radio quiet. Visiting scientists in some instances may wish to bring equipment with them for studying special problems. Within its means, the observatory will provide supporting facilities, including receivers and other electronic devices, computers, laboratories and shops, and housing. Scientists interested in more details concerning arrangements for visitors should direct their inquiries to the National Radio Astronomy Observatory, P. O. Box 2, Green Bank, West Virginia. PMID:17753091

Emberson, R M

1959-11-13

178

Development of an Experimental Phased Array Feed System and Algorithms for Radio Astronomy  

NASA Astrophysics Data System (ADS)

Phased array feeds (PAFs) are a promising new technology for astronomical radio telescopes. While PAFs have been used in other fields, the demanding sensitivity and calibration requirements in astronomy present unique new challenges. This dissertation presents some of the first astronomical PAF results demonstrating the lowest noise temperature and highest sensitivity at the time (66 Kelvin and 3.3 m^2/K, respectively), obtained using a narrowband (425 kHz bandwidth)prototype array of 19 linear co-polarized L-band dipoles mounted at the focus of the Green Bank 20 Meter Telescope at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. Results include spectral line detection of hydroxyl (OH) sources W49N and W3OH, and some of the first radio camera images made using a PAF, including an image of the Cygnus X region. A novel array Y-factor technique for measuring the isotropic noise response of the array is shown along with experimental measurements for this PAF. Statistically optimal beamformers (Maximum SNR and MVDR) are used throughout the work. Radio-frequency interference (RFI) mitigation is demonstrated experimentally using spatial cancelation with the PAF. Improved RFI mitigation is achieved in the challenging cases of low interference-to-noise ratio (INR) and moving interference by combining subspace projection (SP) beamforming with a polynomial model to track a rank 1 subspace. Limiting factors in SP are investigated including sample estimation error, subspace smearing, noise bias, and spectral scooping; each of these factors is overcome with the polynomial model and prewhitening. Numerical optimization leads to the polynomial subspace projection (PSP) method, and least-squares fitting to the series of dominant eigenvectors over a series of short term integrations (STIs) leads to the eigenvector polynomial subspace projection (EPSP) method. Expressions for the gradient, Hessian, and Jacobian are given for use in numerical optimization. Results are given for simulated and experimental data, demonstrating deeper beampattern nulls by 6 to 30dB. To increase the system bandwidth toward the hundreds of MHz bandwidth required by astronomers for a fully science-ready instrument, an FPGA digital backend is introduced using a 64-input analog-to-digital converter running at 50 Msamp/sec and the ROACH processing board developed at the University of California, Berkeley. International efforts to develop digital back ends for large antenna arrays are considered, and a road map is proposed for development of a hardware correlator/beamformer at BYU using three ROACH boards communicating over 10 gigabit Ethernet.

Landon, Jonathan C.

179

New Mexico Fiber-Optic Link Marks Giant Leap Toward Future of Radio Astronomy  

NASA Astrophysics Data System (ADS)

SOCORRO, NM -- Scientists and engineers at the National Radio Astronomy Observatory (NRAO) have made a giant leap toward the future of radio astronomy by successfully utilizing the Very Large Array (VLA) radio telescope in conjunction with an antenna of the continent-wide Very Long Baseline Array (VLBA) using the longest fiber-optic data link ever demonstrated in radio astronomy. The 65-mile fiber link will allow scientists to use the two National Science Foundation (NSF) facilities together in real time, and is the first step toward expanding the VLA to include eight proposed new radio-telescope antennas throughout New Mexico. LEFT: Miller Goss, NRAO's director of VLA/VLBA Operations, unveils graphic showing success of the Pie Town-VLA fiber link. The project, funded by the NSF and Associated Universities, Inc. (AUI), which operates NRAO for the NSF, links the VLA and the VLBA antenna in Pie Town, NM, using a Western New Mexico Telephone Co. fiber-optic cable. The successful hookup was announced at a ceremony that also marked the 10th anniversary of NRAO's Operations Center in Socorro. "Linking the Pie Town antenna to the VLA quadruples the VLA's ability to make detailed images of astronomical objects," said Paul Vanden Bout, NRAO's Director. "This alone makes the link an advance for science, but its greater importance is that it clearly demonstrates the technology for improving the VLA's capabilities even more in the future." "Clearly, the big skies and wide open spaces in New Mexico create near perfect conditions for the incredible astronomical assets located in our state. This new fiber-optic link paves the way for multiplying the already breathtaking scientific capabilities of the VLA," Senator Pete Domenici (R-NM) said. The VLA is a system of 27 radio-telescope antennas distributed over the high desert west of Socorro, NM, in the shape of a giant "Y." Made famous in movies, commercials and numerous published photos, the VLA has been one of the most productive and versatile astronomical observatories in the world since its dedication in 1980. The VLBA is a continent-wide system of 10 radio telescopes distributed across the continental United States, Hawaii and St. Croix in the Caribbean. In both the VLA and VLBA, the cosmic radio waves received by each antenna are combined with those received from every other antenna in the system to produce images with extremely great resolving power, or ability to see fine detail. The more widely separated the antennas, the greater the resolving power. The greatest separation between antennas of the VLA is 20 miles; in the VLBA, 5,000 miles. If your eyes could see the same level of detail as the VLA, you could, at the distance from New York to Los Angeles, make out an object the size of a small car. With the resolving power of the VLBA, you could read the owner's manual. The VLBA can make images hundreds of times more detailed than those available from the Hubble Space Telescope. However, because of the way in which such multi-antenna radio telescopes, called interferometers, work, there is a gap between the levels of detail obtainable with the VLA and the VLBA. Linking the VLA to the VLBA Pie Town antenna is the first step toward filling in that gap and allowing astronomers to see all scales of structure -- small, medium-sized, and large -- in objects such as stars, galaxies and quasars. Additional antennas, distributed throughout New Mexico, would fully fill that gap. Adding the new antennas to the VLA "would provide the capability to image astronomical objects on all spatial scales, from the very largest to the very smallest. The combination of the VLA and VLBA then would be the only single instrument in astronomy covering such a range of spatial scales, and thus a tool of great and unique value to science," said Vanden Bout. LEFT: NRAO Director Paul Vanden Bout, left, speaks with U.S. Senator Pete Domenici, right, following the ceremony at the Array Operations Center in Socorro Dec. 15. Nobel Laureate Robert Wilson is in the ba

1998-12-01

180

Instrumental and Observational Studies in Radio Astronomy, Low Noise Amplifier Design and Methanol Maser Research  

NASA Astrophysics Data System (ADS)

``Radio astronomy is the study of the universe by observing electromagnetic radiation after it has been amplified. The use of amplifiers that preserve the oscillatory character of radiation - the phase information - is the mark of Radio astronomy.'' Thus, the development of low noise amplifiers for microwave and millimeter wavelengths is a major part of Radio astronomy as important as the observations themselves. This technical report involves those two aspects of Radio astronomy, the observational and technical aspects. In the first part, observations of methanol masers in massive star forming regions using Very Long Baseline Interferometry (VLBI) are presented. The second part concerns the realization of low noise amplifiers using in a radio camera. Recent observations have confirmed that the methanol masers are powerful tools for probing the regions of massive star formation. The methanol masers fall in two distinct classes related to their location in the star forming regions. Class I methanol masers are observed offset far away from the UC HII region emission peak. They are certainly collisionally pumped and may occur in the interface between high velocity gas outflows and the ambient molecular material. Class II methanol masers coincide with the UC HII region emission. They may be radiatively pumped by FIR radiation from the dust grains and reside either in spherical layers surrounding the UC HII regions or in circumstellar discs. The maser spots are usually compact (~1-10 AU) and lie in region of physical conditions n(H)~104-108 cm-3 and T=100-1000 K. CH3OH may be produced by hydrogenation of CO on the surface of the icy mantles of the dust grains . The methanol is then injected in the molecular gas by evaporation of the ice (n(H)=106 cm-3, T=100-300 K). In this report we present VLBI observations of 6.7 and 12.2 GHz methanol masers in the star forming regions NGC7538, W75N and S252. Our results show the existence of two groups of masers in NGC7538. The first group exhibits a linear velocity gradient and forms a line in our VLBI map which is consistent with a rotating disc of masers seen edge-on around a massive star. The second group of masers are blueshifted with respect to the first group and lie in a conical region south of the inferred disc. We argue that these masers probably arise in an outflow emerging approximately perpendicularly to the disc. We find that the maser positions at 6.7 and 12.2 GHz are coincident and those of the second group correspond approximately to the absolute positions of NH3, H2CO and OH masers associated with the radio-continuum and infrared source NGC7538-IRS1. In addition we find similar evidence for circumstellar discs of masers in W75N and S252. For these three sources associated with ultra compact HII regions, from the linear velocity gradients and assuming that the central protostars are massive, we derive that the radii of the circumstellar discs are in the range 300-1200 AU which is typical of protoplanetary discs. In the second part, we present the design and realization of 4 GHz cryogenic low noise amplifiers used as IF amplifiers in a radio-camera receiver (SISYFOS project) which will be installed in the Onsala 20m millimeter wave telescope. The requirements of the SISYFOS project at cryogenic temperature are a minimum gain of 25 dB and noise equivalent temperature less than 10 K over the frequency range 3.4-4.6 GHz. Because of its low noise and high gain properties, the MGF4310E series super low noise HEMT from Mitsubishi have been selected to satisfy these requirements. We show that a very simple input design using a high impedance series line viewed as a series inductor provides good matching over a broad bandwidth while ensuring the stability of the amplifier. The minimum noise equivalent temperature and gain of the amplifier measured at cryogenic ambient temperature over the specified bandwidth are 7 K and 28 dB respectively.

Minier, V.

1998-10-01

181

New Book Recounts Exciting, Colorful History Of Radio Astronomy in Green Bank, West Virginia  

NASA Astrophysics Data System (ADS)

A new book published by the National Radio Astronomy Observatory (NRAO) tells the story of the founding and early years of the Observatory at Green Bank, West Virginia. But it was Fun: the first forty years of radio astronomy at Green Bank, is not a formal history, but rather a scrapbook of early memos, recollections, anecdotes and reports. But it was Fun... is liberally illustrated with archival photographs. It includes historical and scientific papers from symposia held in 1987 and 1995 to celebrate the birthdays of two of the radio telescopes at the Observatory. Book cover The National Radio Astronomy Observatory was formed in 1956 after the National Science Foundation decided to establish an observatory in the eastern United States for the study of faint radio signals from distant objects in the Universe. But it was Fun... reprints early memos from the group of scientists who searched the mountains for a suitable site -- an area free from radio transmitters and other sources of radio interference -- "in a valley surrounded by as many ranges of high mountains in as many directions as possible," which was "at least 50 miles distant from any city or other concentration of people." The committee settled on Green Bank, a small village in West Virginia, and the book documents the struggles that followed to create a world-class scientific facility in an isolated area more accustomed to cows than computers. Groundbreaking at the Observatory, then a patchwork of farms and fields, took place in October 1957, only a few days after the launch of Sputnik by the Soviet Union. A year later, Green Bank's first telescope was dedicated, and the book contains a transcription of speeches given at that ceremony, when the Cold War, the space race and America's scientific stature were issues of the hour. The centerpiece of the new Observatory was to be a highly-precise radio telescope 140 feet in diameter, but it was expected that it would soon be surpassed by dishes of much greater size. The book reprints internal memos, reports, and recollections of astronomers who were there, as the initial elation turned to frustration when the 140 Foot Telescope project became mired in technical difficulties, plans for larger dishes were put on hold, and the scientific staff of the fledgling Observatory struggled to create a National Observatory with inadequate equipment in a very remote location. Articles by David Heeschen and John Findlay tell the story of the creation of the 300 Foot Telescope, at that time the largest in the world, which went from initial concept to full operation in only 23 months, and began a rich life of research that put the NRAO on the world scientific map. The 300 Foot Telescope was originally intended to be an interim instrument, but as documented in the book, demand for its use was so high that it was kept in operation long after its initial planned retirement, with regular upgrades and new generations of electronics. The sudden collapse of the 300 Foot Telescope on a calm evening after 26 years of operation shocked the astronomical community. But it was Fun... features dramatic first-hand accounts by the people who were there that night: the telescope operator who found himself under a falling structure; the Observatory staff who at first could not believe what happened, and those who worked during the night and into the next day to secure the area, preserve information on what happened, and deal with the rush of publicity. The book includes extensive photographs and the Executive Summary Report of the panel which was commissioned to investigate the collapse and its implication for the design of other large radio telescopes. But it was Fun... will appeal to a variety of audiences. Historians of science will be interested in the articles by David Heeschen, Gerald Tape, and Hugh van Horn, on the evolution of the concept of a National Observatory, and the difficulties of putting the concepts into practice in Green Bank. Those interested in astronomical discovery will find fascinating and highly personal a

2007-07-01

182

The radio astronomy experiment on Helios A and B /E 5c/. [using dipole antenna-preamplifier-radiometer system  

NASA Technical Reports Server (NTRS)

The NASA Goddard Space Flight Center radio astronomy experiment on Helios, identified as Experiment 5c, has sixteen observing frequencies over the range of 26.5 to 3000 kHz. The antenna consists of two extendible 15-m booms, forming an electric dipole, two high-impedance preamplifiers located at the root of the booms, and the 16-channel radiometer. Important information about propagation conditions, such as absorption, scattering and refraction, are expected from observations of radio emission regions at distances between 1 and 0,3 AU.

Weber, R. R.

1975-01-01

183

A Collision of Interests - Protecting Radio Astronomy from Interference in a Free-Market Environment  

NASA Astrophysics Data System (ADS)

The protection of radio astronomy (RA) from radio frequency interference (RFI) is becoming increasingly difficult. Established mechanisms for the management of spectrum in the United States and throughout the world have provided a degree of protection from RFI by assigning certain bands to RA on an exclusive or shared use basis. Explosive growth in commercial spectrum use has created spectrum crowding outside the RA bands, especially at lower frequencies below 3 GHz. Constellations of low-earth-orbit satellites are a particular problem to RA in that they always have transmitters above the horizon and these transmitters can spill unwanted emissions into the RA bands from their adjacent operating bands. The desire to study the early Universe presents a new challenge for RA with respect to RFI. The RA protected bands were selected for frequencies of important spectral lines. For objects in the distant, redshifted Universe, these lines can appear at all frequencies below the rest frequency and observations may be needed where the RA bands offer no protection. The growing needs of RA occur at the same time that commercial demand for spectrum is driving the Federal Communications Commission and the International Telecommuncations Union to consider entirely new approaches to spectrum management. These approaches would favor intensive commercial use of spectrum over scientific use in that decisions would be largely based on economic and efficient use considerations. It has even been proposed by some proponents of change in spectrum management policy that the entire spectrum be sold to the highest bidders in one global auction. While this is unlikely to happen, it is indicative of the climate in which RA spectrum managers currently work.

Vanden Bout, P. A.

2004-05-01

184

Detection of dust impacts by the Voyager planetary radio astronomy experiment  

NASA Technical Reports Server (NTRS)

The Planetary Radio Astronomy (PRA) instrument detected large numbers of dust particles during the Voyager 2 encounter with Neptune. The signatures of these impacts are analyzed in some detail. The major conclusions are described. PRA detects impacts from all over the spacecraft body, not just the PRA antennas. The signatures of individual impacts last substantially longer than was expected from complementary Plasma Wave Subsystem (PWS) data acquired by another Voyager experiment. The signatures of individual impacts demonstrate very rapid fluctuations in signal strength, so fast that the data are limited by the speed of response of the instrument. The PRA detects events at a rate consistently lower than does the Plasma Wave subsystem. Even so, the impact rate is so great near the inbound crossing of the ring plane that no reliable estimate of impact rate can be made for this period. The data are consistent with the presence of electrons accelerated by ions within an expanding plasma cloud from the point of impact. An ancillary conclusion is that the anomalous appearance of data acquired at 900 kHz appears to be due to an error in processing the PRA data prior to their delivery rather than due to overload of the PRA instrument.

Evans, David R.

1993-01-01

185

Radio Telescopes Extend Astronomy's Best "Yardstick," Provide Vital Tool for Unraveling Dark Energy Mystery  

NASA Astrophysics Data System (ADS)

Radio astronomers have directly measured the distance to a faraway galaxy, providing a valuable "yardstick" for calibrating large astronomical distances and demonstrating a vital method that could help determine the elusive nature of the mysterious Dark Energy that pervades the Universe. Galaxy UGC 3789 Visible-light image of UGC 3789 CREDIT: STScI "We measured a direct, geometric distance to the galaxy, independent of the complications and assumptions inherent in other techniques. The measurement highlights a valuable method that can be used to determine the local expansion rate of the Universe, which is essential in our quest to find the nature of Dark Energy," said James Braatz, of the National Radio Astronomy Observatory (NRAO), who presented the work to the American Astronomical Society's meeting in Pasadena, California. Braatz and his colleagues used the National Science Foundation's Very Long Baseline Array (VLBA) and Robert C. Byrd Green Bank Telescope (GBT), and the Effelsberg Radio Telescope of the Max Planck Institute for Radioastronomy (MPIfR) in Germany to determine that a galaxy dubbed UGC 3789 is 160 million light-years from Earth. To do this, they precisely measured both the linear and angular size of a disk of material orbiting the galaxy's central black hole. Water molecules in the disk act as masers to amplify, or strengthen, radio waves the way lasers amplify light waves. The observation is a key element of a major effort to measure the expansion rate of the Universe, known as the Hubble Constant, with greatly improved precision. That effort, cosmologists say, is the best way to narrow down possible explanations for the nature of Dark Energy. "The new measurement is important because it demonstrates a one-step, geometric technique for measuring distances to galaxies far enough to infer the expansion rate of the Universe," said Braatz. The GBT Robert C. Byrd Green Bank Telescope CREDIT: NRAO/AUI/NSF The VLBA Very Long Baseline Array CREDIT: NRAO/AUI/NSF Dark Energy was discovered in 1998 with the observation that the expansion of the Universe is accelerating. It constitutes 70 percent of the matter and energy in the Universe, but its nature remains unknown. Determining its nature is one of the most important problems in astrophysics. "Measuring precise distances is one of the oldest problems in astronomy, and applying a relatively new radio-astronomy technique to this old problem is vital to solving one of the greatest challenges of 21st Century astrophysics," said team member Mark Reid of the Harvard-Smithsonian Center for Astrophysics (CfA). The work on UGC 3789 follows a landmark measurement done with the VLBA in 1999, in which the distance to the galaxy NGC 4258 -- 23 million light-years -- was directly measured by observing water masers in a disk of material orbiting its central black hole. That measurement allowed refinement of other, indirect distance-measuring techniques using variable stars as "standard candles." The measurement to UGC 3789 adds a new milepost seven times more distant than NGC 4258, which itself is too close to measure the Hubble Constant directly. The speed at which NGC 4258 is receding from the Milky Way can be influenced by local effects. "UGC 3789 is far enough that the speed at which it is moving away from the Milky Way is more indicative of the expansion of the Universe," said team member Elizabeth Humphreys of the CfA. Following the achievement with NGC 4258, astronomers used the highly-sensitive GBT to search for other galaxies with similar water-molecule masers in disks orbiting their central black holes. Once candidates were found, astronomers then used the VLBA and the GBT together with the Effelsberg telescope to make images of the disks and measure their detailed rotational structure, needed for the distance measurements. This effort requires multi-year observations of each galaxy. UGC 3789 is the first galaxy in the program to yield such a precise distance. Team member Cheng-Yu Kuo of the University of V

2009-06-01

186

Radar astronomy  

Microsoft Academic Search

Radar Astronomy is a new and growing branch of Astronomy. Although it seems that radio echo studies must be confined to the solar system, they can play an important part in developing our understanding of the Sun and the planets. At the present time these objects are barely detectable by radar techniques and much of the work has been concerned

J. V. Evans

1960-01-01

187

Ambient and Cryogenic, Decade Bandwidth, Low Noise Receiving System for Radio Astronomy Using Sinuous Antenna  

NASA Astrophysics Data System (ADS)

Traditionally, radio astronomy receivers have been limited to bandwidths less than an octave, and as a result multiple feeds and receivers are necessary to observe over a wide bandwidth. Next generation of instruments for radio astronomy will benefit greatly from reflector antenna feeds that demonstrate very wide instantaneous bandwidth, and exhibit low noise behavior. There is an increasing interest in wideband systems from both the cost and science point of view. A wideband feed will allow simultaneous observations or sweeps over a decade or more bandwidth. Instantaneous wide bandwidth is necessary for detection of short duration pulses. Future telescopes like square kilometer array (SKA), consisting of 2000 to 3000 coherently connected antennas and covering a frequency range of 70 MHz to 30 GHz, will need decade bandwidth single pixel feeds (SPFs) along with integrated LNAs to achieve the scientific objectives in a cost effective way. This dissertation focuses on the design and measurement of a novel decade bandwidth sinuous-type, dual linear polarized, fixed phase center, low loss feed with an integrated LNA. A decade bandwidth, low noise amplifier is specially designed for noise match to the higher terminal impedance encountered by this antenna yielding an improved sensitivity over what is possible with conventional 50 O amplifiers. The self-complementary, frequency independent nature of the planar sinuous geometry results in a nearly constant beam pattern and fixed phase center over more than a 10:1 operating frequency range. In order to eliminate the back-lobe response over such a wide frequency range, we have projected the sinuous pattern onto a cone, and a ground plane is placed directly behind the cone's apex. This inverted, conical geometry assures wide bandwidth operation by locating each sinuous resonator a quarter wavelength above the ground plane. The presence of a ground plane near a self complementary antenna destroys the self complementary nature of the composite structure resulting in frequency dependent impedance variations. We demonstrate, using simulations and measurements, how the return loss can be improved by modifying the sinuous geometry. The feed-LNA combination is characterized for important properties such as return loss, system noise, far field beam patterns including cross-polarization over a wide frequency range. The system is developed as a feed for a parabolic reflector. The overall system performance is calculated in terms of the A/Tsys ratio. A cryogenic version would have a direct impact on specialized observing applications requiring large instantaneous bandwidths with high sensitivity. A novel cryogenic implementation of this system is demonstrated using a Stirling cycle, one-stage refrigerator. The cryocooler offers advantages like low cost, light weight, small size, low power consumption, and does not require routine maintenance. The higher antenna input impedance and a balanced feeding method for the sinuous antenna offers a unique set of challenges when developing a cryogenic system.

Gawande, Rohit Sudhir

188

CONFERENCES AND SYMPOSIA: The Pushchino Radio Astronomy Observatory of the P N Lebedev Physical Institute Astro Space Center: yesterday, today, and tomorrow  

NASA Astrophysics Data System (ADS)

The development of Russian (formerly Soviet) radio astronomy is indissolubly linked with the P N Lebedev Physical Institute (LPI), Russian Academy of Sciences. From the late 1940s, the institute conducted most of its radio astronomy research in the Crimea, at stations or on field trips; in the late 1950s, the center of gravity of research moved to the southern Moscow region, where one of the largest radio astronomy observatories in the country and in the world was developed within less than twenty years. The observatory unique instrumentation system is briefly reviewed in a historical perspective. Key research areas and some major achievements are outlined, and the prospects of the observatory as (currently) part of the LPI Astro Space Center are examined.

Dagkesamanskii, Rustam D.

2009-11-01

189

8 LINCOLN LABORATORY JOURNAL n VOLUME 21, NUMBER 1, 2014 InsIghts Into the UnIverse: Astronomy wIth hAystAck's rAdIo telescope  

E-print Network

wIth hAystAck's rAdIo telescope Insights into the Universe: Astronomy with Haystack's Radio Telescope game-changing tech- nology for radio science, and to apply it to the study of our planet, its space projects. The observatory is operated under an agreement with the Northeast Radio Observatory Corporation

Williams, Brian C.

190

The Eclipsing Radio Emission of the Precataclysmic Binary Institute of Astronomy & Astrophysics, Academia Sinica,  

E-print Network

The Eclipsing Radio Emission of the Precataclysmic Binary V471 Tau Jeremy Lim Institute confirming the presence of eclipses in the centime­ ter radio emission of the eclipsing binary V471 Tau eclipse per orbit: in all we observed one near--complete radio eclipse, the ingress phase of two other

White, Stephen

191

The Contribution of the Division of Radiophysics Murraybank Field Station to International Radio Astronomy  

NASA Astrophysics Data System (ADS)

During the 1950s Australia was one of the world's foremost astronomical nations owing primarily to the work of the dynamic radio astronomy group within the Commonwealth Scientific and Industrial Research Organisation's Division of Radiophysics. Most of the observations were made at the network of field stations maintained by the Division in or near Sydney, and one of these field stations was Murraybank in the north-western suburbs of Sydney. GVaucouleursDe1954The Magellanic Clouds and the GalaxyThe Observatory7423311954Obs....74...23DDe Vaucouleurs, G., 1954a. The Magellanic Clouds and the Galaxy. The Observatory, 74, 23-31. GVaucouleursDe1954The Magellanic Clouds and the Galaxy, IIThe Observatory741581641954Obs....74..158DDe Vaucouleurs, G., 1954b. The Magellanic Clouds and the Galaxy, II. The Observatory, 74, 158-164. GVaucouleursDe1961Classification and radial velocities of bright southern galaxiesMemoirs of the Royal Astronomical Society6869871961MmRAS..68...69DDe Vaucouleurs, G., 1961. Classification and radial velocities of bright southern galaxies. Memoirs of the Royal Astronomical Society, 68, 69-87. JDeane2006Vacuum Tube SupercomputerSydneyScience Foundation for Physics and the Australian Computer Museum SocietyDeane, J., 2006. Vacuum Tube Supercomputer. Sydney, Science Foundation for Physics and the Australian Computer Museum Society. NHDeiter1965Neutral

Wendt, Harry; Orchiston, Wayne; Slee, Bruce

192

Discovering astronomy  

NASA Technical Reports Server (NTRS)

An overview of basic astronomical knowledge is presented with attention to the structure and dynamics of the stars and planets. Also dealt with are techniques of astronomical measurement, e.g., stellar spectrometry, radio astronomy, star catalogs, etc. Basic physical principles as they pertain to astronomy are reviewed, including the nature of light, gravitation, and electromagnetism. Finally, stellar evolution and cosmology are discussed with reference to the possibility of life elsewhere in the universe.

Chapman, R. D.

1978-01-01

193

The SKA Mid-frequency All-sky Continuum Survey: Discovering the unexpected and transforming radio-astronomy  

E-print Network

We show that, in addition to specific science goals, there is a strong case for conducting an all-sky (i.e. the visible 3-pi steradians) SKA continuum survey which does not fit neatly into conventional science cases. History shows that the greatest scientific impact of most major telescopes (e.g., HST, VLA) lies beyond the original goals used to justify the telescope. The design of the telescope therefore needs to maximise the ultimate scientific productivity, in addition to achieving the specific science goals. In this chapter, we show that an all-sky continuum survey is likely to achieve transformational science in two specific respects: (1) Discovering the unexpected (2) Transforming radio-astronomy from niche to mainstream

Norris, Ray P; Brown, Michael; Carretti, Ettore; Kapinska, Anna D; Prandoni, Isabella; Rudnick, Lawrence; Seymour, Nick

2014-01-01

194

A 5 Giga Samples Per Second 8-Bit Analog to Digital Printed Circuit Board for Radio Astronomy  

NASA Astrophysics Data System (ADS)

We have designed, manufactured, and characterized an 8-bit 5 Giga samples per second (Gsps) ADC printed circuit board assembly (PCBA). An e2v EV8AQ160 ADC chip was used in the design and the board is plug compatible with the field programmable gate array (FPGA) board developed by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER) community. Astronomical interference fringes were demonstrated across a single baseline pair of antennas using two ADC boards on the Yuan Tseh Lee Array for Microwave Background Anisotropy (AMiBA) telescope. Several radio interferometers are using this board for bandwidth expansion, such as Submillimeter Array; also, several experimental telescopes are building new spectrometers using the same board. The ADC boards were attached directly to the Reconfigurable Open Architecture Computing Hardware (ROACH-2) FPGA board for processing of the digital output signals. This ADC board provides the capability of digitizing radio frequency signals from DC to 2 GHz (3 dB bandwidth), and to an extended bandwidth of 2.5 GHz (5 dB) with derated performance. The following worst-case performance parameters were obtained over 2 GHz: spur free dynamic range (SFDR) of 44 dB, signal-to-noise and distortion (SINAD) of 35 dB, and effective number of bits (ENOB) of 5.5.

Jiang, Homin; Liu, Howard; Guzzino, Kim; Kubo, Derek; Li, Chao-Te; Chang, Ray; Chen, Ming-Tang

2014-09-01

195

International Symposium on Millimeter and Submillimeter Wave Radio Astronomy, Granada, Spain, September 11-14, 1984, Proceedings  

NASA Astrophysics Data System (ADS)

Various papers on millimeter and submillimeter wave radio astronomy are presented. The topics discussed include: the Nobeyama 45 m telescope, analysis of the time constants in the thermal model for the UK-NL millimeter wave telescope, new generation CFRP sub-mm telescope, the UA/MPIfR submillimeter telescope, telescope testing by radio holography, millimeter and submillimeter interferometry, the Caltech millimeter wave interferometer, the Nobeyama millimeter-wave interferometer, the IRAM interferometer, the SAO submillimeter telescope array project, at VLBI at 90 GHz. Also addressed are: superconducting and Schottky mixers, Caltech SIS receivers, IRAM SIS receivers, SIS mixer development at NRAO, a 2K closed cycle cryogenerator, phase-locked 65-115 GHz Gunn oscillator, bolometer systems developed at MPIfR, current far-infrared spectrometers, acoustooptical spectrometers, far-infrared heterodyne spectroscopy, spiral arm structure of molecular gas in M51, millimeter-wavelength interferometry of Orion-KL, density structure of molecular cloud cores, star formation in dense cores in nearby dark clouds, and extragalactic hot spots at mm wavelengths.

196

Characterizing Interference in Radio Astronomy Observations through Active and Unsupervised Learning  

NASA Technical Reports Server (NTRS)

In the process of observing signals from astronomical sources, radio astronomers must mitigate the effects of manmade radio sources such as cell phones, satellites, aircraft, and observatory equipment. Radio frequency interference (RFI) often occurs as short bursts (< 1 ms) across a broad range of frequencies, and can be confused with signals from sources of interest such as pulsars. With ever-increasing volumes of data being produced by observatories, automated strategies are required to detect, classify, and characterize these short "transient" RFI events. We investigate an active learning approach in which an astronomer labels events that are most confusing to a classifier, minimizing the human effort required for classification. We also explore the use of unsupervised clustering techniques, which automatically group events into classes without user input. We apply these techniques to data from the Parkes Multibeam Pulsar Survey to characterize several million detected RFI events from over a thousand hours of observation.

Doran, G.

2013-01-01

197

Analysis of the Capability and Limitations of Relativistic Gravity Measurements Using Radio Astronomy Methods  

NASA Technical Reports Server (NTRS)

The uses of radar observations of planets and very-long-baseline radio interferometric observations of extragalactic objects to test theories of gravitation are described in detail with special emphasis on sources of error. The accuracy achievable in these tests with data already obtained, can be summarized in terms of: retardation of signal propagation (radar), deflection of radio waves (interferometry), advance of planetary perihelia (radar), gravitational quadrupole moment of sun (radar), and time variation of gravitational constant (radar). The analyses completed to date have yielded no significant disagreement with the predictions of general relativity.

Shapiro, I. I.; Counselman, C. C., III

1975-01-01

198

Recent solar radio astronomy at centimeter wavelengths: the temporal variability of the 10. 7-cm flux  

Microsoft Academic Search

Studies made by means of high-resolution radio telescopes indicate that solar centrimetric emission contains contributions from many different sources and involves more than one radiation mechanism. Two emission components have been identified: bright, compact sources and weaker, diffuse emission which is distributed over the plage and surrounding areas of enhanced magnetic field. There is evidence for the occurrence of weaker

K. F. Tapping

1987-01-01

199

NAIC/NRAO School on Single Dish Radio Astronomy ASP Conference Series, Vol. , 2001  

E-print Network

the telescope observe a point source (i.e. a source which is considerably smaller than the beam size) which has, Arecibo, PR 00612; koneil@naic.edu Abstract. Calibrating telescope data is one of the most important is to calibrate radio telescope data in the centimeter wavelength regime. This includes a discussion of the var

O'Neil, Karen

200

Broadband beamforming of dense aperture array (DAA) and focal plane array (FPA) signals using 3D spatio-temporal filters for applications in aperture synthesis radio astronomy  

Microsoft Academic Search

It is shown that 3D spatio-temporal filters have potential applications in aperture synthesis radio astronomy for the broadband-beamforming\\u000a of the array of signals that is received from dense aperture arrays (DAAs) and also from focal plane arrays (FPAs). In particular,\\u000a we consider possible applications for the planned Square Kilometer Array (SKA) project where broadband beamforming is required\\u000a at the front-end

Thushara K. Gunaratne; Len T. Bruton

2011-01-01

201

Radio telescopes  

Microsoft Academic Search

A radio telescope is used in radio astronomy to measure the intensity of the radiation received from various parts of the sky. Such a telescope must be able both to detect and to locate faint radio sources of small angular size, and also to measure the brightness distribution across extended radio sources or over large sky areas. Ideally the telescope

J. Findlay

1964-01-01

202

The application of compressive sampling to radio astronomy II: Faraday rotation measure synthesis  

E-print Network

Faraday rotation measure (RM) synthesis is an important tool to study and analyze galactic and extra-galactic magnetic fields. Since there is a Fourier relation between the Faraday dispersion function and the polarized radio emission, full reconstruction of the dispersion function requires knowledge of the polarized radio emission at both positive and negative square wavelengths $\\lambda^2$. However, one can only make observations for $\\lambda^2 > 0$. Furthermore observations are possible only for a limited range of wavelengths. Thus reconstructing the Faraday dispersion function from these limited measurements is ill-conditioned. In this paper, we propose three new reconstruction algorithms for RM synthesis based upon compressive sensing/sampling (CS). These algorithms are designed to be appropriate for Faraday thin sources only, thick sources only, and mixed sources respectively. Both visual and numerical results show that the new RM synthesis methods provide superior reconstructions of both magnitude and p...

Li, Feng; Cornwell, Tim J; de Hoog, Frank

2011-01-01

203

Low noise, 0.4-3 GHz cryogenic receiver for radio astronomy.  

PubMed

We present the design and measurement of a radio telescope receiver front end cooled to 100 K physical temperature, and working over 400 MHz to 3 GHz frequency band. The system uses a frequency independent feed developed for operation as a feed for parabola using sinuous elements and integrated with an ultra-wideband low noise amplifier. The ambient temperature system is tested on the 43 m radio telescope in Green Bank, WV and the system verification results on the sky are presented. The cryogenic receiver is developed using a Stirling cycle, one stage cryocooler. The measured far field patterns and the system noise less than 80 K over a 5:1 bandwidth are presented. PMID:25362437

Gawande, R; Bradley, R; Langston, G

2014-10-01

204

The application of compressive sampling to radio astronomy. II. Faraday rotation measure synthesis  

NASA Astrophysics Data System (ADS)

Faraday rotation measure (RM) synthesis is an important tool to study and analyze galactic and extra-galactic magnetic fields. Since there is a Fourier relation between the Faraday dispersion function and the polarized radio emission, full reconstruction of the dispersion function requires knowledge of the polarized radio emission at both positive and negative square wavelengths ?2. However, one can only make observations for ?2 > 0. Furthermore observations are possible only for a limited range of wavelengths. Thus reconstructing the Faraday dispersion function from these limited measurements is ill-conditioned. In this paper, we propose three new reconstruction algorithms for RM synthesis based upon compressive sensing/sampling (CS). These algorithms are designed to be appropriate for Faraday thin sources only, thick sources only, and mixed sources respectively. Both visual and numerical results show that the new RM synthesis methods provide superior reconstructions of both magnitude and phase information than RM-CLEAN.

Li, F.; Brown, S.; Cornwell, T. J.; de Hoog, F.

2011-07-01

205

Low noise, 0.4-3 GHz cryogenic receiver for radio astronomy  

NASA Astrophysics Data System (ADS)

We present the design and measurement of a radio telescope receiver front end cooled to 100 K physical temperature, and working over 400 MHz to 3 GHz frequency band. The system uses a frequency independent feed developed for operation as a feed for parabola using sinuous elements and integrated with an ultra-wideband low noise amplifier. The ambient temperature system is tested on the 43 m radio telescope in Green Bank, WV and the system verification results on the sky are presented. The cryogenic receiver is developed using a Stirling cycle, one stage cryocooler. The measured far field patterns and the system noise less than 80 K over a 5:1 bandwidth are presented.

Gawande, R.; Bradley, R.; Langston, G.

2014-10-01

206

*** TITLE *** Reports on Astronomy 2009-2012  

E-print Network

be transformed into a parking lot in support of the ATST. In 2003, the National Radio Astronomy Observatory on HISTORICAL RADIO ASTRONOMY CHAIR Kenneth Kellermann VICE-CHAIR Wayne Orchiston BOARD Rod Davies Leonid TRIENNIAL REPORT 2009-2012 1. Introduction The IAU Working Group on Historical Radio Astronomy (WGHRA

Groppi, Christopher

207

Application of Field System-FS9 and a PC to Antenna Control Unit interface in Radio Astronomy in Peru  

NASA Astrophysics Data System (ADS)

We are in the process to transform a 32m antenna in Peru, used for telecommunications, into a Radio Telescope to perform Radio Astronomy in Peru. The 32m antenna of Peru constructed by NEC was used for telecommunications with communications satellites at 6 GHz for transmission, and 4 GHz for reception. In collaboration of National Institute of Information and Communications Technology (NICT) Japan, and National Observatory of Japan we developed an Antenna Control System for the 32m antenna in Peru. It is based on the Field System FS9, software released by NASA for VLBI station, and an interface to link PC within FS9 software (PC-FS9) and Antenna Control Unit (ACU) of the 32 meters antenna. The PC-FS9 controls the antenna, commands are translated by interface into control signals compatibles with the ACU using: an I/O digital card with two 20bits ports to read azimuth and elevation angles, one 16bits port for reading status of ACU, one 24bits port to send pulses to start or stop operations of antenna, two channels are analogic outputs to drive the azimuth and elevation motors of the antenna, a LCD display to show the status of interface and error messages, and one serial port for communications with PC-FS9,. The first experiment of the control system was made with 11m parabolic antenna of Kashima Space Research Center (NICT), where we tested the right working of the routines implemented for de FS9 software, and simulations was made with looped data between output and input of the interface, both test were done successfully. With this scientific instrument we will be able to contribute with researching of astrophysics. We expect to into a near future to work at 6.7GHz to study Methanol masers, and higher frequencies with some improvements of the surface of the dish.

Vidal, E. V. S.; Ishitsuka, J. I. I.; Koyama, K. Y.

2006-08-01

208

Space-qualified wideband and ultrawideband acousto-optical spectrometers for millimeter and submillimeter radio astronomy  

NASA Astrophysics Data System (ADS)

Acousto-optical techniques are particularly well suited for wide band spectroscopy in astrophysical and geophysical applications using millimeter and sub-millimeter heterodyne radiometers aboard spacecraft. An illustration is given by the 1 GHz AOS built for the ODIN, sub-millimeter telescope in Earth's orbit. We describe the spectrometer, including the IF down converter, AO processor, data acquisition and pre- processing sub-systems. The used technology, space qualification of the critical components as well as relevant environmental and electrical results are presented. The acousto-optical technique can also be used for compact, ultra wide band spectrometers (2000 to 4000 channels over 4 GHz bandwidth or more). Scientific applications include sub- millimeter missions in Astronomy (FIRST) as well in Geophysics (Microwave Limb Sounding programs). Performances obtained on prototypes built in Meudon Observatory are presented and the characteristics achievable for near future systems are analyzed. They fit well with the presently retained design of the heterodyne (HET) instrument on FIRST, based on a font-end system made of a four band, dual polarization receiver, allowing for full frequency coverage from 480 to 1250 MHz.

Lecacheux, Alain; Rosolen, Carlo; Michet, Daniel; Clerc, V.

1998-07-01

209

Controller-area-network bus control and monitor system for a radio astronomy interferometer.  

PubMed

We describe the design and implementation of a controller-area-network bus (CANbus) monitor and control system for a millimeter wave interferometer. The Combined Array for Research in Millimeter-wave Astronomy (CARMA) is a 15-antenna connected-element interferometer for astronomical imaging, created by the merger of two university observatories. Its new control system relies on a central computer supervising a variety of subsystem computers, many of which control distributed intelligent nodes over CANbus. Subsystems are located in the control building and in individual antennas and communicate with the central computer via Ethernet. Each of the CAN modules has a very specific function, such as reading an antenna encoder or tuning an oscillator. Hardware for the modules was based on a core design including a commercial CANbus-enabled single-board computer and some standard circuitry for interfacing to peripherals. Hardware elements were added or changed as necessary for the specific module types. Similarly, a base set of embedded code was implemented for essential common functions such as CAN message handling and time keeping and extended to implement the required functionality for the different hardware. Using a standard CAN messaging protocol designed to fit the requirements of CARMA and a well-defined interface to the high-level software allowed separate development of high-level code and embedded code with minimal integration problems. Over 30 module types have been implemented and successfully deployed in CARMA, which is now delivering excellent new science data. PMID:17902962

Woody, David P; Wiitala, Bradley; Scott, Stephen L; Lamb, James W; Lawrence, Ronald P; Giovanine, Curt; Fredsti, Sancar J; Beard, Andrew; Pryke, Clem; Loh, Michael; Greer, Christopher H; Cartwright, John K; Gutierrez-Kraybill, Colby; Bolatto, Alberto D; Muchovej, Stephen J C

2007-09-01

210

Solar maximum mission: Ground support programs at the Harvard Radio Astronomy Station  

NASA Technical Reports Server (NTRS)

Observations of the spectral characteristics of solar radio bursts were made with new dynamic spectrum analyzers of high sensitivity and high reliability, over the frequency range 25-580 MHz. The observations also covered the maximum period of the current solar cycle and the period of international cooperative programs designated as the Solar Maximum Year. Radio data on shock waves generated by solar flares were combined with optical data on coronal transients, taken with equipment on the SMM and other satellites, and then incorporated into computer models for the outward passage of fast-mode MHD shocks through the solar corona. The MHD models are non-linear, time-dependent and for the most recent models, quasi-three-dimensional. They examine the global response of the corona for different types of input pulses (thermal, magnetic, etc.) and for different magnetic topologies (for example, open and closed fields). Data on coronal shocks and high-velocity material ejected from solar flares have been interpreted in terms of a model consisting of three main velocity regimes.

Maxwell, A.

1983-01-01

211

Observations of Cygnus X-3 at the Mullard Radio Astronomy Observatory  

NASA Astrophysics Data System (ADS)

THE radio outbursts1 of Cygnus X-3 have been observed at several frequencies since September 4, 1972. We have made measurements of the flux density variations at 5.0, 2.7 and 1.4 GHz, and the position and an upper limit to the angular size at 5 GHz; in addition the HI absorption spectrum has been determined and upper limits have been placed on the flux densities at 150 and 81.5 MHz. The instruments used were the Five-Kilometre (5 GHz), One-Mile (2.7 and 5 GHz) and Half-Mile (1.4 GHz) telescopes, the 4C antenna (150 MHz) and the 4 acre array (81.5 MHz).

Branson, N. J. B. A.; Martin, A. H. M.; Pooley, G. G.; Readhead, A. C. S.; Shakeshaft, J. R.; Slingo, A.; Warner, P. J.

1972-10-01

212

Radio Astronomy Data Model for Single-Dish Multiple-Feed Telescopes, and Robledo Archive Architecture  

E-print Network

All the effort that the astrophysical community has put into the development of the Virtual Observatory (VO) has surpassed the non-return point: the VO is a reality today, and an initiative that will self-sustain, and to which all archival projects must adhere. We have started the design of the scientific archive for the DSS-63 70-m antenna at NASA's DSN station in Robledo de Chavela (Madrid). Here we show how we can use all VO proposed data models to build a VO-compliant single-dish, multiple-feed, radio astronomical archive data model (RADAMS) suitable for the archival needs of the antenna. We also propose an exhaustive list of Universal Content Descriptors (UCDs) and FITS keywords for all relevant metadata. We will further refine this data model with the experience that we will gain from that implementation.

J. D. Santander-Vela; E. Garcia; J. F. Gomez; L. Verdes-Montenegro; S. Leon; R. Gutierrez; C. Rodrigo; O. Morata; E. Solano; O. Suarez

2008-10-02

213

VLA observations of stellar planetary nebulae. [using Very Large Array at National Radio Astronomy Observatory  

NASA Technical Reports Server (NTRS)

Coordinates, dimensions, 4885-MHz flux densities, and brightness temperatures of K3-2, NGC 6833, Ps 1, II 5117, Me 2-2, Hb 12, Vy 1-1, and M1-5 are reported. In two other cases, H3-29 and H3-75, confused extended structure was detected in which the nebula could not be identified with certainty. He 2-467, M1-2, and Peterson's H-alpha object in M15 were also included in the observations but not detected with an upper limit of less than 10 mJy. The observations are compared with some of the previous optical and radio data, such as log S(H-beta). Distances are computed from the present data with standard assumptions. Corresponding linear radii range below 0.1 pc, among the smallest in previous distributions of radius.

Johnson, H. M.; Balick, B.; Thompson, A. R.

1979-01-01

214

Peta-Flop Real Time Radio Astronomy Signal Processing Instrumentation and the CASPER Collaboration  

NASA Astrophysics Data System (ADS)

I will briefly describe next generation radio telescopes, such as HERA and the Square Kilometer Array (SKA), which will require 1E15 to 1E17 operations per second of real time processing. I'll present some of the new architectures we've used to develop a variety of heterogeneous FPGA-GPU-CPU based signal processing systems for such telescopes, including spectrometers, correlators, and beam formers. I will also describe the CASPER collaboration, which has developed architectures, open source programming tools, libraries and reference designs that make it relatively easy to develop a variety of scalable, upgradeable, fault tolerant, low power, real time digital signal processing instrumentation. CASPER utilizes commercial 10Gbit and 40 Gbit ethernet switches to interconnect open source general purpose field programmable gate array (FPGA) boards with GPUs and software modules. CASPER collaborators at hundreds of universities, government labs and observatories have used these techniques to rapidly develop and deploy a variety of correlators, beamformers, spectrometers, pulsar/transient machines, and VLBI instrumentation. CASPER instrumentation is also utilized in physics, medicine, genomics and engineering. Open source source hardware, software, libraries, tools, tutorials, reference designs, information about workshops, and how to join the collaboration are available at http://casper.berkeley.edu

Werthimer, Dan

2014-04-01

215

Absolute Calibration of the Radio Astronomy Flux Density Scale from 22 to 43 GHz using Planck  

NASA Astrophysics Data System (ADS)

The Planck mission detected hundreds of extragalactic radio sources at frequencies from 28 to 857 GHz. Since Planck's calibration is absolute, based on the satellite's annual motion around the Sun, and since its beams are well-characterized at the sub-percent levels, Planck's flux density measurements are absolute to percent-level accuracy. We have made coordinated Planck, VLA and ATCA observations of ~60 strong, unresolved sources in order to compare Planck's absolute calibration to that used by these two interferometers at 22, 28 and 43 GHz. The flux densities of the sources used to calibrate the VLA observations are taken from Perley and Butler (2013), which is fundamentally based on models of the planet Mars calibrated via WMAP observations. The flux densities of the sources used to calibrate the ATCA observations are based on models of the planet Uranus. Despite the scatter introduced by the variability of many of the sources, the three flux density scales are determined to agree to 1-2% accuracy.

Butler, Bryan J.; Partridge, R. Bruce; Perley, Richard A.; Stevens, Jamie B.; Lopez-Caniego, Marcos; Rocha, Graca; Walter, Ben Z.; Zacchei, Andrea

2015-01-01

216

ASTRONOMY AND ASTROPHYSICS Type III radio bursts observed by Ulysses pole to pole,  

E-print Network

Abstract. We consider 555 type III bursts observed by Ulysses and/or Wind while Ulysses traversed a large range of longitude and latitude. We find: 1) The percentage of bursts seen by both spacecraft was 59.5%. It was higher, about 80%, when Ulysses was to the south and east of the Sun as seen from Wind. It decreased to about 50 % when Ulysses was near the ecliptic behind the Sun, and it remained near 50 % as Ulysses moved to the north and west. 2) The distribution of low frequency cutoffs flo of type III radiation is very similar for bursts seen by Ulysses and those seen by Wind, whereas the distribution of the in-situ plasma frequency fp at the two spacecraft is very different. Many bursts descend to close to fp ? 30 kHz at Wind but few descend to the lower fp ? 10 kHz at Ulysses. We confirm earlier findings that flo is rarely lower than about 20 kHz. 3) Statistically, the low frequency limit depends strongly on the burst intensity, being about four times lower for strong bursts than for weak bursts. We consider three hypotheses for the close relation between intensity and flo: proximity of the burst source to one spacecraft or the other, directivity and propagation effects, and density and speed of the fast electron stream. We conclude that, while the first two may be important for some bursts, for many others the character of the electron stream is the dominant factor in establishing both the burst intensity and the lowest frequency attained. Key words: Sun: radio radiation activity corona 1.

Simultaneously Wind; Y. Leblanc; G. A. Dulk; S. Hoang; J. -l. Bougeret; P. A. Robinson

1996-01-01

217

Fast gain calibration in radio astronomy using alternating direction implicit methods: Analysis and applications  

NASA Astrophysics Data System (ADS)

Context. Modern radio astronomical arrays have (or will have) more than one order of magnitude more receivers than classical synthesis arrays, such as the VLA and the WSRT. This makes gain calibration a computationally demanding task. Several alternating direction implicit (ADI) approaches have therefore been proposed that reduce numerical complexity for this task from 𝒪(P3) to 𝒪(P2), where P is the number of receive paths to be calibrated Aims: We present an ADI method, show that it converges to the optimal solution, and assess its numerical, computational and statistical performance. We also discuss its suitability for application in self-calibration and report on its successful application in LOFAR standard pipelines. Methods: Convergence is proved by rigorous mathematical analysis using a contraction mapping. Its numerical, algorithmic, and statistical performance, as well as its suitability for application in self-calibration, are assessed using simulations. Results: Our simulations confirm the 𝒪(P2) complexity and excellent numerical and computational properties of the algorithm. They also confirm that the algorithm performs at or close to the Cramer-Rao bound (CRB, lower bound on the variance of estimated parameters). We find that the algorithm is suitable for application in self-calibration and discuss how it can be included. We demonstrate an order-of-magnitude speed improvement in calibration over traditional methods on actual LOFAR data. Conclusions: In this paper, we demonstrate that ADI methods are a valid and computationally more efficient alternative to traditional gain calibration methods and we report on its successful application in a number of actual data reduction pipelines.

Salvini, Stefano; Wijnholds, Stefan J.

2014-11-01

218

Society News: Monica Grady awarded CBE; Grubb Parsons Lecture 2012; Join the RAS; Astronomy on radio for kids; New Fellows; Peter D Hingley  

NASA Astrophysics Data System (ADS)

RAS Fellow Prof. Monica Grady has been made a Commander of the Most Excellent Order of the British Empire (CBE), in recognition of her services to space science. The RAS sponsors the annual Grubb Parsons Lecture, which this year took place on 6 June at the University of Durham. If you are a professional astronomer, geophysicist, or similar, a student studying these disciplines, or simply someone with a serious interest in them, we urge you to apply for membership of the RAS. Outreach is an important activity for the RAS. We recently supported an astronomy series called Deep Space High on the digital radio channel Fun Kids.

2012-08-01

219

Astronomy research at the Aerospace Corporation. [research projects - NASA programs  

NASA Technical Reports Server (NTRS)

This report reviews the astronomy research carried out at The Aerospace Corporation during 1974. The report describes the activities of the San Fernando Observatory, the research in millimeter wave radio astronomy as well as the space astronomy research.

Paulikas, G. A.

1974-01-01

220

The Green Bank Solar Radio Burst Spectrometer  

E-print Network

National Radio Astronomy Observatory Technology Center 1180 Boxwood Estate Rd, Charlottesville, VA 22903 S at the Green Bank Site of the National Radio Astronomy Observatory in the National Radio Quiet Zone, where Radio Astronomy Observatory 520 Edgemont Rd, Charlottesville, VA 22903 R. A. Bradley & E. Mastrantonio

White, Stephen

221

Recycling for radio astronomy  

NASA Astrophysics Data System (ADS)

Melvin Hoare, Steve Rawlings and the CUGA consortium look forward to the potential offered by recycling the 30 m class antennas at Goonhilly Earth Station in Cornwall, including a new deep-space tracking facility, research and training, and the possibility of enhancing the e-MERLIN array.

Hoare, Melvin

2012-02-01

222

Automated radio astronomy operations  

NASA Technical Reports Server (NTRS)

The improvements in using a computer to drive a DSN 64-meter antenna are described. The development is used to simplify operation, improve antenna safety, reduce antenna wear, present the abuse of antenna by misoperation, increase quantity and quality of data gathered, and give users a greater choice of automatic operations.

Livermore, R. W.

1978-01-01

223

NATIONAL RADIO ASTRONOMY OBSERVATORY  

E-print Network

which event the results could be hazardous). Radiation cooling of the mylar film by the cold innards electrical loss. To prevent this, the mylar can be dried by air from a small fan. This report describes to reduce radiative cooling of the plastic film and radiative warming of the cold contents of the dewar

Groppi, Christopher

224

MARTHA PATRICIA HAYNES Goldwin Smith Professor of Astronomy, Cornell University  

E-print Network

scientist, National Radio Astronomy Observatory responsible for daily operations at rural telescope site scientist, National Radio Astronomy Observatory 1997 visiting scientist, European Southern Observatory 1998 with National Science Foundation for operation of the National Radio Astronomy Observatory and for $29M design

Richardson Jr., James E.

225

Transactions IAU, Volume XXVIIIA Reports on Astronomy 2009-2012  

E-print Network

site on 11 May 2011. In 2003, the National Radio Astronomy Observatory initiated the first Archives de its participation in multi- institutional collaborations. As the national facility for radio astronomy GROUP ON HISTORICAL RADIO ASTRONOMY CHAIR Kenneth Kellermann VICE-CHAIR Wayne Orchiston BOARD Rod Davies

Groppi, Christopher

226

A Voyage through the Radio Universe  

ERIC Educational Resources Information Center

Each year, professionals and amateurs alike make significant contributions to the field of astronomy. High school students can also conduct astronomy research. Since 1992, the Radio Astronomy Research Team from Oil City Area Senior High School (OCHS) in Oil City, Pennsylvania, has traveled each year to the National Radio Astronomy Observatory

Spuck, Timothy

2004-01-01

227

A Cryogenic Ultra-Low-Noise MMIC-based LNA with a discrete First Stage Transistor Suitable for Radio Astronomy Applications  

E-print Network

In this paper a new design of MMIC based LNA is outlined. This design uses a discrete 100-nm InP HEMT placed in front of an existing InP MMIC LNA to lower the overall noise temperature of the LNA. This new approach known as the Transistor in front of MMIC (T+MMIC) LNA, possesses a gain in excess of 40dB and an average noise temperature of 9.4K compared to 14.5K for the equivalent MMIC-only LNA measured across a 27-33GHz bandwidth at a physical temperature of 8K. A simple ADS model offering further insights into the operation of the LNA is also presented and a potential radio astronomy application is discussed

McCulloch, Mark A; Piccirillo, Lucio

2013-01-01

228

Radio Observations of Rapidly Rotating F--M Dwarf Stars in the Institute of Astronomy & Astrophysics, Academia Sinica,  

E-print Network

Radio Observations of Rapidly Rotating F--M Dwarf Stars in the Pleiades Jeremy Lim Institute very rapidly rotating late­ type dwarf stars in the Pleiades open cluster, distributed in spectral: evolution ­ stars: flare ­ stars: late­ type 1. INTRODUCTION The radio emission of active late­type dwarf

White, Stephen

229

Multiwavelength Astronomy  

NSDL National Science Digital Library

This site from NASA's Infrared Astrophysics Data Center explains how the universe can be observed using the entire electromagnetic spectrum. There is an introduction to using light in astronomy; information on and images taken from different areas of the electromagnetic spectrum of objects in the solar system, the Milky Way galaxy and beyond; and a table of radiation types, their characteristic temperatures, and objects emitting this type of radiation. The tutorial explains how observations are made using X-rays, gamma rays, ultraviolet light, visible light, infrared wavelengths, and radio wavelengths. There is a section on why telescopes are sent to space and a multiwavelength gallery.

Linda Hermans-Killam

230

The role of the atmosphere in satellite geodesy, radio astronomy and other applications of trans-atmospheric propagation of radio waves  

Microsoft Academic Search

The influence of the atmosphere on radio waves relevant to technological applications is investigated theoretically, and the associated errors are classified and defined. Range errors are defined as the length of the phase path minus the geometric distance, and range errors are divided into those related to the troposphere and those related to the ionosphere. Ground-path error and group delay

R. Leitinger

1990-01-01

231

South Africa's new radio telescope reveals giant outbursts from binary star system May 16th, 2013 in Space & Earth / Astronomy  

E-print Network

(double) star system. Two stars orbit each other every 16.5 days in an elliptical orbit. The small white (double) star system. Two stars orbit each other every 16.5 days in an elliptical orbit. The small #12South Africa's new radio telescope reveals giant outbursts from binary star system May 16th, 2013

Jarrett, Thomas H.

232

A scientific program for infrared, submillimeter and radio astronomy from space: A report by the Management Operations Working Group  

NASA Technical Reports Server (NTRS)

Important and fundamental scientific progress can be attained through space observations in the wavelengths longward of 1 micron. The formation of galaxies, stars, and planets, the origin of quasars and the nature of active galactic nuclei, the large scale structure of the Universe, and the problem of the missing mass, are among the major scientific issues that can be addressed by these observations. Significant advances in many areas of astrophysics can be made over the next 20 years by implementing the outlined program. This program combines large observatories with smaller projects to create an overall scheme that emphasized complementarity and synergy, advanced technology, community support and development, and the training of the next generation of scientists. Key aspects of the program include: the Space Infrared Telescope Facility; the Stratospheric Observatory for Infrared Astronomy; a robust program of small missions; and the creation of the technology base for future major observatories.

1989-01-01

233

ASTRONOMY 104: UNDERGRADUATE ASTRONOMY SEMINAR  

E-print Network

1 ASTRONOMY 104: UNDERGRADUATE ASTRONOMY SEMINAR SYLLABUS Unique Number 47750 Class Meetings together with fellow astronomy majors, and those in other majors who are keen on astronomy. We hope to discuss present and future pathways to success in and around astronomy, and to share with you some

234

Elementary astronomy  

NASA Astrophysics Data System (ADS)

In developing nations such as Mexico, basic science education has scarcely improved. There are multiple reasons for this problem; they include poor teacher training and curricula that are not challenging for students. I shall suggest ways in which astronomy can be used to improve basic education, it is so attractive that it can be employed to teach how to read and write, learn a second language, mathematics, physics, as well as geography. If third world nations do not teach science in an adequate way, they will be in serious problems when they will try to achieve a better standard of living for their population. I shall also address informal education, it is by this means that most adults learn and keep up to date with subjects that are not their specialty. If we provide good outreach programs in developing nations we can aid adult training; astronomy is ideal since it is particularly multidisciplinary. In particular radio and television programs are useful for popularization since they reach such wide audiences.

Fierro, J.

2006-08-01

235

Experimental Astronomy (2004) 17: 261267 C Springer 2005 RFI MITIGATION AND THE SKA  

E-print Network

Experimental Astronomy (2004) 17: 261­267 C Springer 2005 RFI MITIGATION AND THE SKA STEVEN W radio astronomy from its inception. The Workshop on the Mitigation of Radio Frequency Interference in Radio Astronomy (RFI2004) was held in Penticton, BC, Canada in July 2004 in order to consider

Ellingson, Steven W.

236

A Radio Transient 0.1 pc from Sagittarius A* Geoffrey C. Bower1  

E-print Network

60208; doug- roberts,zadeh@northwestern.edu 4 National Radio Astronomy Observatory, Charlottesville, VA 22903; bcotton@nrao.edu 5 National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801; mgoss-rays: binaries 1 Astronomy Department & Radio Astronomy Laboratory, University of California, Berkeley, CA 94720

Bower, Geoffrey

237

A Group Sparsity Imaging Algorithm for Transient Radio Sources Stephan Wengera  

E-print Network

Braunschweig, Germany b National Radio Astronomy Observatory, Socorro, NM 87801, USA Abstract RadioA Group Sparsity Imaging Algorithm for Transient Radio Sources Stephan Wengera , Urvashi Raub. Keywords: radio interferometry, compressed sensing, sparse recovery 1. Introduction Radio interferometers

Magnor, Marcus

238

4918 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 51, NO. 10, OCTOBER 2013 Radio Frequencies: Policy and Management  

E-print Network

. I. Kellermann and A. R. Thompson are with the National Radio Astronomy Observatory is operated a summary of this framework for radio scientists and engineers. Index Terms--Radio astronomy, radioBoer is with the Radio Astronomy Laboratory, University of Cali- fornia at Berkeley, Berkeley, CA 94720 USA (e

Long, David G.

239

Astronomy Across Africa  

NASA Astrophysics Data System (ADS)

African astronomy is growing rapidly. The Southern African Large Telescope is the largest optical telescope in the southern hemisphere, MeerKat and the Square Kilometer Array will revolutionize radio astronomy in the coming decade, and Namibia hosts HESS II, the worlds largest gamma-ray telescope. A growing community of observational and theoretical astronomers utilizes these multi-wavelength observational facilities. The largest concentrations of researchers are in southern Africa, but the community is now expanding across the continent. Substantial resources are being invested in developing the next generation of African astronomers. The African Astronomical Society was formed in 2011 to foster and coordinate the growth of the science in Africa. The IAU has located its global Office of Astronomy for Development in South Africa, with the mandate to find innovative ways of using astronomy to promote social and educational development around the world. African astronomy offers abundant opportunities for collaborative research with colleagues from across the globe. This special session will introduce many of the aspects of African astronomy to the US community, with the aim of engendering new partnerships and strengthening existing ones.

Williams, Ted

2014-01-01

240

Multimessenger Astronomy  

E-print Network

Multimessenger astronomy incorporating gravitational radiation is a new and exciting field that will potentially provide significant results and exciting challenges in the near future. With advanced interferometric gravitational wave detectors (LCGT, LIGO, Virgo) we will have the opportunity to investigate sources of gravitational waves that are also expected to be observable through other messengers, such as electromagnetic (gamma-rays, x-rays, optical, radio) and/or neutrino emission. The LIGO-Virgo interferometer network has already been used for multimessenger searches for gravitational radiation that have produced insights on cosmic events. The simultaneous observation of electromagnetic and/or neutrino emission could be important evidence in the first direct detection of gravitational radiation. Knowledge of event time, source sky location, and the expected frequency range of the signal enhances our ability to search for the gravitational radiation signatures with an amplitude closer to the noise floor of the detector. Presented here is a summary of the status of LIGO-Virgo multimessenger detection efforts, along with a discussion of questions that might be resolved using the data from advanced or third generation gravitational wave detector networks.

N. L. Christensen; for the LIGO Scientific Collaboration; the Virgo Collaboration

2011-05-30

241

Astronomy 111 Introduction to Astronomy  

E-print Network

: 1. Tools of Astronomy: The Physics and History of Astronomy; Energy; Light; Spectra 2. Planets of the semester will be on conceptual understanding. (Astronomy 100, offered Spring 2013, is an alternative course, and Energy) and the processes that govern them; and · Understand how science works, and how we know what we

Lowenthal, James D.

242

Early Astronomy  

NASA Astrophysics Data System (ADS)

The earliest investigations that can be called scientific are concerned with the sky: they are the beginnings of astronomy. Many early civilizations produced astronomical texts, and several cultures that left no written records left monuments and artifacts-ranging from rock paintings to Stonehenge-that show a clear interest in astronomy. Civilizations in China, Mesopotamia, India and Greece had highly developed astronomies, and the astronomy of the Mayas was by no means negligible. Greek astronomy, as developed by the medieval Arab philosophers, evolved into the astronomy of Copernicus. This displaced the earth from the central stationary position that almost all earlier astronomies had assumed. Soon thereafter, in the first decades of the seventeenth century, Kepler found the true shape of the planetary orbits and Galileo introduced the telescope for astronomical observations.

Thurston, Hugh

243

IAC-02-IAA.2.3.01 Dishing up the Data: the role of Australian space tracking and radio astronomy facilities in the  

E-print Network

.Sarkissian@csiro.au Abstract The recent Australian film, The Dish, highlighted the role played by the Parkes Radio Telescope's major radio telescope facilities was being established at Parkes, in western New South Wales. This 64 Radio Telescope has been contracted by NASA on many occasions to support interplanetary spacecraft

Sarkissian, John M.

244

Astron. Astrophys. 357, L45--L48 (2000) ASTRONOMY ASTROPHYSICS  

E-print Network

­Planck­Institut f? ur Radioastronomie, Auf dem H? ugel 69, 53121 Bonn, Germany 2 National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801­0387, USA 3 University of Michigan, Astronomy Department, Ann Arbor, MI 48109­1090, USA 4 Mets? ahovi Radio Observatory, Metsahovintie, 02540 Kylm? al? a, Finland

Brunthaler, Andreas

245

National Radio Astronomy Observatory (1)  

Microsoft Academic Search

Just one hundred years ago, J.C. Bose described to the Royal Institution in London his research carried out in Calcutta at millimeter wavelengths. He used waveguides, horn antennas, dielectric lenses, various polarizers and even semiconductors at frequencies as high as 60 GHz; much of his original equipment is still in existence, now at the Bose Institute in Calcutta. Some concepts

Jagadis Chandra Bose; D. T. Emerson

2003-01-01

246

The Radio Transient Sky  

Microsoft Academic Search

Transient radio sources are necessarily compact and usually are the locations of explosive or dynamic events, therefore offering unique opportunities for probing fundamental physics and astrophysics. In addition, short-duration transients are powerful probes of intervening media owing to dispersion, scattering, and Faraday rotation that modify the signals. While radio astronomy has an impressive record obtaining high time resolution, usually it

J. Lazio; P. S. Ray; S. Ellingson; S. Close; P. Crane; S. D. Hyman; B. A. Jacoby; W. Junor; N. E. Kassim; S. R. Kulkarni; Y. M. Pihlstrom; G. B. Taylor; D. Werthimer

2006-01-01

247

Bad Astronomy  

NSDL National Science Digital Library

Philip Plait, a professor at the physics and astronomy department at Sonoma State University, explores many popular myths and misconceptions about astronomy at this amusing and educational website. Students and educators can learn which ideas promoted by television, news, movies, and the general public are false and, more importantly, why they are false. Amateur astronomers can talk with others about an array of bad astronomy topics on the Bulletin Board. The website offers information about Philip Plait's public talks and about astronomical events.

Plait, Philip

248

Astronomy Development in Nigeria: Challenges and Advances  

NASA Astrophysics Data System (ADS)

Nigeria evidently has huge potentials to develop a strong astronomy community. Much of the strength lies in the great number of intelligent students with the potential of becoming good astronomers. Sadly, astronomy development in Nigeria has stagnated in the past decades owing to poor funding and/or indifferent attitude of the funding bodies, research-unfriendly environment, and non-existence of facilities. Currently, efforts toward fuelling advancement in astronomy are focused on building critical mass, establishing collaborations with universities/astronomy institutes outside Nigeria, converting out-of-use communication antennas into radio telescopes, and acquiring out-of-use telescopes for educational and low-level research purposes.

Okwe Chibueze, James

2015-01-01

249

DATA REDUCTION OF HYPERSPECTRAL RADIO-ASTRONOMICAL IMAGES FOR GALAXY CLUSTER SEGMENTATION  

E-print Network

as in the infrared on wide and remote objects. Whereas good quality spectroscopic data cubes are a relatively new phenomenon in optical astronomy, they are commonly used for more than twenty years in radio astronomy- tant for whole astronomy. 1.1. Radio-lines observation Data cubes from radio line observations contain

250

Multiwavelength Observations of the Second Largest Known FRII Radio Galaxy, NVSS 2146+82  

E-print Network

H. Bridle National Radio Astronomy Observatory3 Steven R. Majewski4 & Craig L. Sarazin Department upper limits on 1NOAO WIYN Queue Investigator 2National Radio Astronomy Observatory Jansky Pre-Doctoral Fellow 3The National Radio Astronomy Observatory is a facility of the National Science Foundation

Bridle, Alan

251

National Radio Observatory  

NSDL National Science Digital Library

The National Radio Astronomy Observatory (NRAO) "operates powerful, advanced radio telescopes spanning the western hemisphere." The website is nicely divided into information for the general public, astronomers, and teachers and students. Users can learn all about NRAO's many telescopes located throughout the United States. Researchers can find out about meetings, conferences, software resources, and surveys. Amateur radio astronomers can find links describing how to build antennas and interferometers. Everyone will enjoy the numerous images of astronomical phenomena and NRAO's telescopes and facilities.

252

Astronomy Today  

NSDL National Science Digital Library

Astronomy Today has a great many articles on all subjects relevant to space and our Universe. The site touches on topics like amateur astronomy, telescope advice, string theory and quantum gravity. This site offers information about the planets, space exploration, constellations, meteors, comets, cosmology, and much more. The information is very clear cut and easy to understand.

Delehanty, Marc

2005-06-07

253

Primary Astronomy.  

ERIC Educational Resources Information Center

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics

Greenstone, Sid; Smith, Murray

254

Intermediate Astronomy.  

ERIC Educational Resources Information Center

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics

Greenstone, Sid; Smith, Murray

255

Richard Conn Henry is a Professor in the Henry A. Rowland Department of Physics & Astronomy, at The Johns Hopkins University in Baltimore, Maryland, USA,  

E-print Network

, observational astronomy, radio astronomy, ultraviolet astronomy, and X-ray astronomy; and one book, "AtlasRichard Conn Henry is a Professor in the Henry A. Rowland Department of Physics & Astronomy on investigation of the origin of the cosmic diffuse ultraviolet background radiation: is there a dark matter

256

HIGH SENSITIVITY SIDEBAND-SEPARATING RECEIVERS FOR MILLIMETER ASTRONOMY: ACHIEVING THE ULTIMATE IN ASTROPHYSICAL SPECTROSCOPY  

E-print Network

, AZ, 85721; and A. R. KERR, National Radio Astronomy Observatory, Charlottesville, VA. High resolution of the National Radio Astronomy Observatory (NRAO), new receiver architecture has been developed and put in use. RIELAND, R. W. FREUND, Arizona Radio Observatory, and Steward Observatory, University of Arizona, Tucson

Ziurys, Lucy M.

257

Astronomy in Iraq  

NASA Astrophysics Data System (ADS)

The history of modern Iraqi astronomy is reviewed. During the early 1970's Iraqi astronomy witnessed significant growth through the introduction of the subject at university level and extensively within the school curriculum. In addition, astronomy was popularised in the media, a large planetarium was built in Baghdad, plus a smaller one in Basra. Late 1970 witnessed the construction of the Iraqi National Observatory at Mount Korek in Iraqi Kurdistan. The core facilities of the Observatory included 3.5-meter and 1.25-meter optical telescopes, and a 30-meter radio telescope for millimetre wavelength astronomy. The Iraqi Astronomical Society was founded and Iraq joined the IAU in 1976. During the regime of Saddam Hussain in the 1980's, the Observatory was attacked by Iranian artillery during the Iraq-Iran war, and then again during the second Gulf war by the US air force. Years of sanctions during the 1990's left Iraq cut off from the rest of the international scientific community. Subscriptions to astronomical journals were halted and travel to conferences abroad was virtually non-existent. Most senior astronomers left the country for one reason or another. Support from expatriate Iraqi astronomers existed (and still exists) however, this is not sufficient. Recent changes in Iraq, and the fall of Saddam's regime, has meant that scientific communication with the outside world has resumed to a limited degree. The Ministry of Higher Education in Baghdad, Baghdad University and the Iraqi National Academy of Science, have all played active roles in re-establishing Iraqi astronomy and re-building the damaged Observatory at Mount Korek. More importantly the University of Sallahudin in Erbil, capital of Iraqi Kurdistan, has taken particular interest in astronomy and the Observatory. Organized visits to the universities, and also to the Observatory, have given us a first-hand assessment of the scale of the damage to the Observatory, as well as the needs of astronomy teaching and research. Joint supervision for postgraduate level research was organized between local and Iraqi expatriate astronomers. The IAU was among the first international organizations to offer assistance. Many observatories worldwide have also given support. Plans will be proposed for re-building the Observatory, supporting teaching and research, and establishing an institute for astronomy in Erbil, together with further suggestions on how the international astronomical community can assist Iraqi astronomers.

Alsabti, A. W.

2006-08-01

258

New horizons in astronomy.  

NASA Technical Reports Server (NTRS)

Besides the study of astronomy itself, other topics included cover the geological and biological developments on earth and basic physics of matter, heat, and light. Optical and radio telescopes are discussed, as well as photographic and photoelectric means of detection. The immediate solar system is described by topics on the properties and atmospheres of the inner and outer planets, the sun's energy, sunspots, and the solar spectrum. Stars both on and off the main sequence are discussed in terms of distances, intrinsic properties, lifetimes and evolution. The Milky Way is compared to other galaxies in size, star population and structure, and the different galaxy shapes are pictured. Topics of most recent interest are covered by results of the lunar explorations, new concepts of Mars, and problems of space travel. Problems of modern astronomy include pulsars, neutron stars, and quasars.

Brandt, J. C.; Maran, S. P.

1972-01-01

259

Signal Processing for Phased Array Feeds in Radio Astronomical Telescopes  

E-print Network

@ee.byu.edu), except : National Radio Astronomy Observatory (NRAO), Charlottesville, VA 22903-2475, rfisher the earliest days of radio astronomy (RA), detecting faint deep space sources has pushed available technologySignal Processing for Phased Array Feeds in Radio Astronomical Telescopes Brian D. Jeffs, Senior

Wirthlin, Michael J.

260

Infrared Astronomy  

NSDL National Science Digital Library

NASA's Infrared Processing and Analysis Center (IPAC) provides the Infrared Astronomy Website as one of its outreach programs. Infrared Astronomy, or "the detection and study of the infrared radiation (heat energy) emitted from objects in the Universe," is described and placed in context in the sections Discovery of Infrared, What is Infrared, Infrared Astronomy, Background, and the Infrared Universe. For current information, see the News & Discoveries, Active/ Future Projects, and Activities sections; past and current projects supported by IPAC are featured in the Infrared Gallery. The site targets a broad audience and is geared towards many learning levels.

261

Ultraviolet Astronomy  

Microsoft Academic Search

Ultraviolet (UV) astronomy is the study of the electromagnetic radiation emitted by celestial bodies in the UV wavelength range, a portion of the spectrum simultaneously shielded by our own atmosphere and beyond the sensory limits of our sight....

L. Buson

2003-01-01

262

Astronomy Communication  

NASA Astrophysics Data System (ADS)

Astronomers communicate all the time, with colleagues of course, but also with managers and administrators, with decision makers and takers, with social representatives, with the news media, and with the society at large. Education is naturally part of the process. Astronomy communication must take into account several specificities: the astronomy community is rather compact and well organized world-wide; astronomy has penetrated the general public remarkably well with an extensive network of associations and organizations of aficionados all over the world. Also, as a result of the huge amount of data accumulated and by necessity for their extensive international collaborations, astronomers have pioneered the development of distributed resources, electronic communications and networks coupled to advanced methodologies and technologies, often much before they become of common world-wide usage. This book is filling up a gap in the astronomy-related literature by providing a set of chapters not only of direct interest to astronomy communication, but also well beyond it. The experts contributing to this book have done their best to write in a way understandable to readers not necessarily hyperspecialized in astronomy nor in communication techniques while providing specific detailed information, as well as plenty of pointers and bibliographic elements. This book will be very useful for researchers, teachers, editors, publishers, librarians, computer scientists, sociologists of science, research planners and strategists, project managers, public-relations officers, plus those in charge of astronomy-related organizations, as well as for students aiming at a career in astronomy or related space science. Link: http://www.wkap.nl/prod/b/1-4020-1345-0

Heck, A.; Madsen, C.

2003-07-01

263

Astron. Astrophys. 357, 507--514 (2000) ASTRONOMY ASTROPHYSICS  

E-print Network

on multi­wavelength monitoring programs. Radio emission in REXRBs is normally highly variable and of non emission of radio loud X­ray binaries J.M. Paredes 1 , J. Mart?? � 2 , M. Peracaula 3,1 , G. Pooley 4, University of Calgary, Calgary, Alberta, T2N IN4, Canada 4 Mullard Radio Astronomy Observatory, Cavendish

Paredes, Josep M.

264

Welcome to the World of Multiwavelength Astronomy  

NSDL National Science Digital Library

Visitors can read and view imagery that explains how additional information can be revealed about celestial objects when they are imaged in multiple wavelengths or in wavelengths outside the visible range. Using the example of the Crab Nebula, this description shows that radio, ultraviolet, and X-ray astronomy reveal additional details of its structure and composition when compared with optical astronomy alone. Links to a glossary of terms are embedded in the text.

265

Minoan Astronomy  

NASA Astrophysics Data System (ADS)

Of the three great cultures of the ancient eastern Mediterranean the Babylonian, Egyptian, and Minoan we have considerable knowledge of the astronomy of the first two through their documents (see relevant sections of this Handbook). Very little written material, however, has survived from Minoan Crete, but the evidence of other impressive archaeological discoveries implies that the inhabitants were on a par with their neighbors and had made similar advances in astronomy. In lieu of written sources, we have used the methods of archaeoastronomy to recover as much as possible about Minoan astronomy. In short, these are measuring the orientations of walls and their opposite horizons at a representative selection of monuments, analyzing the measurements statistically, and comparing the results with digital reconstruction of the positions of significant celestial bodies for the time when the walls were built.

Blomberg, Mary; Henriksson, Gran

266

Conveying astronomy to the public  

NASA Astrophysics Data System (ADS)

The International Year of Astronomy offers us a unique chance to carry out outreach projects in great scale and, to think about new ways to improve our efforts. In this paper I present a few considerations on my activity as a popularisation person. I address its importance and I will emphasize on radio, television and public lectures. I also stress certain ingredients I believe popularisation must include; it must be interesting, diverse, simple, pertinent, and be peer reviewed.

Fierro, Julieta

2011-06-01

267

On gamma-ray astronomy  

Microsoft Academic Search

SummaryPhotons in the visible range form the basis of astronomy. They move in straight lines, which preserves source information,\\u000a but they arise only very indirectly from nuclear or high-energy processes. Cosmic-ray particles, on the other hand, arise\\u000a directly from high-energy processes in astronomical objects of various classes, but carry no information about source direction.\\u000a Radio emissions are still more complex

P. Morrison

1958-01-01

268

Quiz 3 review Astronomy 1161  

E-print Network

waves have a wavelength , a frequency f and a speed c. 2. f = c. In a vacuum, light always travels: 4000-7000 °A 5. Infrared: 7000 °A- 1 mm 6. Microwaves: 1 mm - 0.1 m 7. Radio waves: > 0.1 m · How doesQuiz 3 review Astronomy 1161 1 Light · Explain the properties of light using the wave model. 1. All

Pradhan, Anil

269

Astronomy 362: Observational Astronomy University of Montana  

E-print Network

Astronomy 362: Observational Astronomy University of Montana Fall 2010 T/Th 2:10 ­ 3:30 pm CHCB 227://www.physics.umt.edu/~nate/astr362/ Course Description Observational astronomy relies heavily on application of advanced technology astronomy is dominated by the CCD and related pixel array detectors: digital devices with unprecedented

Vonessen, Nikolaus

270

National Astronomy and Ionosphere Center: Arecibo Observatory  

NSDL National Science Digital Library

The 305m radio telescope at the Arecibo Observatory "is the largest single-dish radio telescope on our planet and is available to the global scientific community for astronomical observation at wavelengths between 6 m and 3 m." Researchers can search WAPP data and information about past, present, and future projects at the Observatory. The extensive website provides numerous data reduction packages and file formats. Users can find extensive materials on the planetary studies, space and atmospheric science, and astronomy occurring at the observatory. Students and educators can learn about Arecibo's summer program. The News link is filled with fascinating new accomplishments, employment opportunities, and upcoming astronomy talks and seminars.

271

The effects of a satellite power system on ground-based astronomy  

NASA Technical Reports Server (NTRS)

The effects of power transmission from the solar power satellite and of radiation from the ground based rectennas on radio astronomy, radar astronomy, and optical astronomy are discussed. Interference sources, acceptable signal and noise levels, and conflicting site requirements for observatories and rectennas are considered.

Thompson, A. R.

1980-01-01

272

Radio Science, Volume ???, Number , Pages 1?? , RFI Identi cation and Mitigation Using Simultaneous  

E-print Network

14853 S. Chatterjee National Radio Astronomy Observatory, 1003 Lopezville Road, Socorro, NM 87801 T. J Observatory, Westford, MA 01886 J. M. Cordes Astronomy Department and NAIC, Cornell University, Ithaca, NY mitigation is a critically important issue in radio astronomy using existing instruments as well

Ellingson, Steven W.

273

Astronomy Books  

NSDL National Science Digital Library

This reference list has 11 kid-friendly books on a wide range of astronomy topics. For each title, the publisher and publication date are included along with author name. The list includes engaging stories, field guides and other reference books.

274

Astronomy Activities.  

ERIC Educational Resources Information Center

This document consists of activities and references for teaching astronomy. The activities (which include objectives, list of materials needed, and procedures) focus on: observing the Big Dipper and locating the North Star; examining the Big Dipper's stars; making and using an astrolabe; examining retograde motion of Mars; measuring the Sun's

Greenstone, Sid

275

Civic Astronomy  

NASA Astrophysics Data System (ADS)

The founding of the Dudley Observatory at Albany, N.Y., in 1852 was a milestone in humanity's age-old quest to understand the heavens. As the best equipped astronomical observatory in the U.S. led by the first American to hold a Ph.D. in astronomy, Benjamin Apthorp Gould Jr., the observatory helped pioneer world-class astronomy in America. It also proclaimed Albany's status as a major national center of culture, knowledge and affluence. This book explores the story of the Dudley Observatory as a 150 year long episode in civic astronomy. The story ranges from a bitter civic controversy to a venture into space, from the banks of the Hudson River to the highlands of Argentina. It is a unique glimpse at a path not taken, a way of doing science once promising, now vanished. As discoveries by the Dudley Observatory's astronomers, especially its second director Lewis Boss, made significant contributions to the modern vision of our Milky Way galaxy as a rotating spiral of more than a million stars, the advance of astronomy left that little observatory behind.

Wise, George

2004-10-01

276

Infrared astronomy  

Microsoft Academic Search

This review paper is a survey of infrared astronomy up to early 1969. The techniques and photometric standards are mentioned briefly, and results cover solar, lunar, and planetary observations. Point sources and extended sources both within and beyond the Galaxy are included, ending with the problem of cosmic background radiation. It is concluded that great progress will be possible when

Ronald F. Webbink; William Q. Jeffers

1969-01-01

277

A Radio Sky Surveys Project with the Allen Telescope Array Contact Author: Geoffrey C. Bower, UC Berkeley, gbower@astro.berkeley.edu  

E-print Network

Space Flight Center), Paul Demorest (National Radio Astronomy Observatory), Rob Ferdman (CNRS, France (University of Virginia), David Nice (Bryn Mawr College), Scott Ransom (National Radio Astronomy Observatory Heiles, Casey Law, Jack Welch (UC Berkeley Radio Astronomy Laboratory), Peter Backus, Samantha Blair

Bower, Geoffrey

278

Astronomy & Astrophysics manuscript no. January 23, 2002 (DOI: will be inserted by hand later)  

E-print Network

National Radio Astronomy Observatory, P.O. Box 0, Socorro, NM 87801, U.S.A. e-mail: julvestaAstronomy & Astrophysics manuscript no. January 23, 2002 (DOI: will be inserted by hand later) Radio Sources in Low-Luminosity Active Galactic Nuclei. III. \\AGNs" in a Distance-Limited Sample

Falcke, Heino

279

Astronomy & Astrophysics manuscript no. freqn2hp.hyper7668 c ESO 2008 November 19, 2008  

E-print Network

by the National Radio Astronomy Observatory which is a facility of the National Science Foundation op- eratedAstronomy & Astrophysics manuscript no. freqn2hp.hyper7668 c ESO 2008 November 19, 2008 and bands ­ Radio lines : ISM 1. Introduction In the quest for star forming cores, kinematic studies play

280

[A chapter prepared for the book \\Information Handling in Astronomy", edited by Andre Heck, to be published by Kluwer. Completed 2000-03-08.  

E-print Network

Radio Astronomy Observatory 2 The history of the Flexible Image Transport System [FITS] is re- viewed for astronomy worldwide, the International Astronomical 1 dwells@nrao.edu 2 The National Radio Astronomy Observatory is a facility of the US National Science Foun- dation operated under cooperative agreement

Wells, Donald C.

281

A Spectral Line Survey of Selected 3 Millimeter Bands toward Sagittarius B2(N-LMH) Using the National Radio Astronomy Observatory 12 Meter Radio Telescope and the Berkeley-Illinois-Maryland Association Array. I. The Observational Data  

Microsoft Academic Search

We have initiated a spectral line survey, at a wavelength of 3 mm, toward the hot molecular core Sgr B2(N-LMH). This is the first spectral line survey of the Sgr B2(N) region utilizing data from both an interferometer (Berkeley-Illinois-Maryland Association [BIMA] array) and a single-element radio telescope (NRAO 12 m). In this survey, covering 3.6 GHz in bandwidth, we detected

D. N. Friedel; L. E. Snyder; B. E. Turner; A. Remijan

2004-01-01

282

Astronomy Magazine  

NSDL National Science Digital Library

Looking to get started as an amateur astronomer? Here are two sites which can help you do just that. The Astronomy Magazine site, provided by Kalmbach Publishing Company, offers a table of contents and a few articles from the print magazine as well as information regarding current sky events, latest news, getting stared as an amateur astronomer, press releases, links to other astronomical sites, and software.

283

Astronomy Workshop  

NSDL National Science Digital Library

The Astronomy Workshop from the University of Maryland features interactives, animations, calculators, and other online computer-assisted learning tools enabling middle-school and older students to investigate the solar system and the universe. Units allow students to investigate astronomical distances and the size of objects in the universe; examine what might happen if objects collide; investigate orbital mechanics; visualize the distribution and motions of objects in the solar system; and many other topics.

Dr. Douglas P. Hamilton

284

Astronomy Animations  

NSDL National Science Digital Library

This collection of animations introduces students to planetary motions, gravitational effects, and the scale of astronomical distances. Students can view visualizations of Earth's changing seasons, circumpolar motion, and the celestial equator and ecliptic plane. Animations on gravity explain how satellites orbit, the motions of comets and meteor storms, and gravitational 'warping'. Other animations explain how Earth's tides are produced, how astronomical distances are calculated, the use of spectra in astronomy, and the lifecycles of stars.

285

Astronomy Animations  

NSDL National Science Digital Library

This collection of animations introduces students to planetary motions, gravitational effects, and the scale of astronomical distances. Students can view visualizations of Earth's changing seasons, circumpolar motion, and the celestial equator and ecliptic plane. Animations on gravity explain how satellites orbit, the motions of comets and meteor storms, and gravitational 'warping'. Other animations explain how Earth's tides are produced, how astronomical distances are calculated, the use of spectra in astronomy, and the lifecycles of stars.

Barnbaum, Cecilia

2011-04-12

286

Astronomy Lessons  

NSDL National Science Digital Library

This collection of astronomy lesson plans and experiments from across the internet was developed by Reach Out, a center linking University of Michigan and community mentors with children and teens. Topics covered include comets, the Sun, sunspots, the aurora, craters, galaxies, moons, star properties, Moon phases, and meteors. Each lesson plan gives credit to the developer, and contains all the information necessary for applying the lesson in a classroom setting.

287

Inuit Astronomy  

NASA Astrophysics Data System (ADS)

Inuit live mainly in the treeless Arctic regions of North America, Greenland, and parts of northeastern Siberia. Their cosmology, based on shamanistic belief, constructed a view of the sky and its contents distinctively suited to their spiritual and pragmatic needs. Their astronomy, particularly for those groups living far above the Arctic Circle, reflects the unique appearance of the celestial sphere at high northerly latitudes, demonstrated most noticeably in the annual disappearance of the sun during midwinter months.

MacDonald, John

288

Humanising Astronomy  

NASA Astrophysics Data System (ADS)

Universe Awareness (UNAWE) is an international programme that aims to expose underprivileged children (in the age group 4-10) to the inspirational aspects of astronomy. We are currently at the stage of developing materials that will be utilised in a diverse range of environments. This paper explores UNAWE's particular approach to developing tools which includes not only indigenous and folkloric astronomical knowledge, but also the culture of transmission of such knowledge. A specific understanding and explanation of the Universe, the Sun, Moon and stars is present in every culture and can be found contained in its history, legends and belief systems. By consciously embracing different ways of knowing the Universe and not uniquely the rational model, UNAWE places the humanising potential of astronomy at the centre of its purpose. Whilst inspiring curiosity, pride and a sense of ownership in one's own cultural identity, such an approach also exposes children to the diversity of other peoples and their cultures as well as the unifying aspects of our common scientific heritage. The means of creating and delivering the astronomy programme are as relevant to the desired educational outcomes as the content. The challenge in the design of materials is to communicate this stimulating message to the very young. Respect for alternative values systems, the need for dialogue and community participation, and where possible the production of materials using local resources is emphasised. This paper touches recent experiences liaising with communities in India, South Africa, Tunisia, Venezuela and Colombia.

Levin, S.

2008-06-01

289

Big data challenges for large radio arrays  

Microsoft Academic Search

Future large radio astronomy arrays, particularly the Square Kilometre Array (SKA), will be able to generate data at rates far higher than can be analyzed or stored affordably with current practices. This is, by definition, a \\

Dayton L. Jones; Kiri Wagstaff; David R. Thompson; Larry D'Addario; Robert Navarro; Chris Mattmann; Walid Majid; Joseph Lazio; Robert Preston; Umaa Rebbapragada

2012-01-01

290

The Radio JOVE Project  

NASA Astrophysics Data System (ADS)

Radio JOVE is an interactive educational activity which brings the radio sounds of Jupiter and the Sun to students, teachers, and the general public. This is accomplished through the construction of a simple radio telescope kit and the use of a real-time radio observatory on the Internet. Our website (http://radiojove.gsfc.nasa.gov/) will contain science information, instruction manuals, observing guides, and education resources for students and teachers. Our target audience is high school science classes, but subjects can be tailored to college undergraduate physics and astronomy courses or even to middle school science classes. The goals of the project are: 1) Educate people about planetary and solar radio astronomy, space physics, and the scientific method 2) Provide teachers and students with a hands-on radio astronomy exercise as a science curriculum support activity by building and using a simple radio telescope receiver/antenna kit 3) Create the first ever online radio observatory which provides real-time data for those with internet access 4) Allow interactions among participating schools by facilitating exchanges of ideas, data, and observing experiences. Our current funding will allow us to impact 100 schools by partially subsidizing their participation in the program. We expect to expand well beyond this number as publicity and general interest increase. Additional schools are welcome to fully participate, but we will not be able to subsidize their kit purchases. We hope to make a wide impact among the schools by advertising through appropriate newsletters, space grant consortia, the INSPIRE project (http://image.gsfc.nasa.gov/poetry/inspire/), electronic links, and science and education meetings. We would like to acknoledge support from the NASA/GSFC Director's Discretionary Fund, the STScI IDEAS grant program and the NASA/GSFC Space Science Data Operations Office.

Garcia, L.; Thieman, J.; Higgins, C.

1999-09-01

291

No Evidence for Evolution in the Far-Infrared-Radio Correlation out to z 2 in the ECDFS  

E-print Network

National Radio Astronomy Observatory, PO Box 2, Green Bank, WV 24944, USA George Helou Infrared Processing Dickinson National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719, USA Dave Frayer Centre for Radio Astronomy Research, M468, University of Western Australia, Crawley, WA 6009, Australia

Norris, Ray

292

Infrared astronomy  

NASA Technical Reports Server (NTRS)

The decade of 1990's presents an opportunity to address fundamental astrophysical issues through observations at IR wavelengths made possible by technological and scientific advances during the last decade. The major elements of recommended program are: the Space Infrared Telescope Facility (SIRTF), the Stratospheric Observatory For Infrared Astronomy (SOFIA) and the IR Optimized 8-m Telescope (IRO), a detector and instrumentation program, the SubMilliMeter Mission (SMMM), the 2 Microns All Sky Survey (2MASS), a sound infrastructure, and technology development programs. Also presented are: perspective, science opportunities, technical overview, project recommendations, future directions, and infrastructure.

Gillett, Frederick; Houck, James; Bally, John; Becklin, Eric; Brown, Robert Hamilton; Draine, Bruce; Frogel, Jay; Gatley, Ian; Gehrz, Robert; Hildebrand, Roger

1991-01-01

293

Planetary astronomy  

NASA Technical Reports Server (NTRS)

The authors profile the field of astronomy, identify some of the key scientific questions that can be addressed during the decade of the 1990's, and recommend several facilities that are critically important for answering these questions. Scientific opportunities for the 1990' are discussed. Areas discussed include protoplanetary disks, an inventory of the solar system, primitive material in the solar system, the dynamics of planetary atmospheres, planetary rings and ring dynamics, the composition and structure of the atmospheres of giant planets, the volcanoes of IO, and the mineralogy of the Martian surface. Critical technology developments, proposed projects and facilities, and recommendations for research and facilities are discussed.

Morrison, David; Hunten, Donald; Ahearn, Michael F.; Belton, Michael J. S.; Black, David; Brown, Robert A.; Brown, Robert Hamilton; Cochran, Anita L.; Cruikshank, Dale P.; Depater, Imke

1991-01-01

294

Astronomy Looks Different When You Listen to It.  

ERIC Educational Resources Information Center

Describes the use of a radio telescope to arouse new interest among students. The article partitions into the following sections: (1) Radio Astronomy--Which Level; (2) First Steps: The Site--The Antenna; (3) The Electronics: Do It Yourself, or Store Bought; (4) Field Test: Music of the Spheres; (5) Getting Started: Entry Level Projects; and (6)

Jones, Richard C.

1994-01-01

295

Early infrared astronomy  

NASA Astrophysics Data System (ADS)

I present a short history of infrared astronomy, from the first scientific approaches of the radiant heat in the seventeenth century to the 1970's, the time when space infrared astronomy was developing very rapidly. The beginning of millimeter and submillimeter astronomy is also covered. As the progress of infrared astronomy was strongly dependent on detectors, some details are given on their development.

Lequeux, James

2009-07-01

296

Astronomy Books of 1985.  

ERIC Educational Resources Information Center

Provides annotated listing of books in 16 areas: (1) amateur astromony; (2) children's books; (3) comets; (4) cosmology; (5) education in astronomy; (6) general astronomy; (7) history of astronomy; (8) life in the universe; (9) miscellaneous; (10) physics and astronomy; (11) pseudo-science; (12) space exploration; (13) stars and stellar evolution;

Mercury, 1986

1986-01-01

297

High-Energy Neutrino Astronomy  

E-print Network

Kilometer-scale neutrino detectors such as IceCube are discovery instruments covering nuclear and particle physics, cosmology and astronomy. Examples of their multidisciplinary missions include the search for the particle nature of dark matter and for additional small dimensions of space. In the end, their conceptual design is very much anchored to the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. The cosmic ray connection sets the scale of cosmic neutrino fluxes. In this context, we discuss the first results of the completed AMANDA detector and the reach of its extension, IceCube. Similar experiments are under construction in the Mediterranean. Neutrino astronomy is also expanding in new directions with efforts to detect air showers, acoustic and radio signals initiated by neutrinos with energies similar to those of the highest energy cosmic rays.

F. Halzen

2005-01-26

298

Mon. Not. R. Astron. Soc. 366, 12651288 (2006) doi:10.1111/j.1365-2966.2005.09916.x CENSORS: A Combined EISNVSS Survey of Radio Sources II.  

E-print Network

- ple was selected from the National Radio Astronomy Obs. Best,2 R. Rengelink2 and H. J. A. R¨ottgering2 1Institute for Astronomy, Royal Observatory Edinburgh EIS­NVSS Survey of Radio Sources (CENSORS) is a 1.4-GHz radio survey selected from the National Radio

Best, Philip

299

Successful Innovative Methods in Introducing Astronomy Courses  

NASA Astrophysics Data System (ADS)

Innovating new informative methods to induce interest in students has permitted us to introduce astronomy in several universities and institutes in Mexico. As a prelude, we gave a popular course in the history of astronomy. This was very easy as astronomy seems to be the most ancient of sciences and relating the achievements of the ancient philosophers/scientists was very enlightening. Then we put up an amateur show of the sky every week (subject to climatic conditions for observability). We showed how to take photographs and make telescopic observations. We enlightened the students of the special missions of NASA and took them to museums for space exploration. We gave a popular seminar on "Astrodynamics," highlighting its importance. We gave a series of introductory talks in radio and T.V. Finally we exposed them to electronic circulars, like "Universe Today" and "World Science." The last mentioned strategy had the most electrifying effect. We may not have been successful without it, as the students began to take the matter seriously only after reading numerous electronic circulars. In this respect, these circulars are not only informative about the latest news in astronomy, but highlight the role of astronomy in the modern world. Without it, students seem to relate astronomy to astrology; it is due to this misconception that they are not attracted to astronomy. Students were hardly convinced of the need for an astronomy course, as they did not know about the scope and development of the subject. This awakened the interests of students and they themselves proposed the initiation of an elementary course in astronomy to have a feel of the subject. Later on they proposed a course on "Rocket Dynamics." We will discuss our methods and their impact in detail.

Chattejee, T. K. C.

2006-08-01

300

Australian Aboriginal Astronomy in the International Year of Astronomy  

E-print Network

1 Australian Aboriginal Astronomy in the International Year of Astronomy Ray P. Norris CSIRO Astronomy & Space Science, NSW, Australia Warawara Dept. The International year of Astronomy seemed an excellent opportunity to tell the wider

Norris, Ray

301

Optical and Radio Emission from the Galactic Supernova Remnant HB 3 (G132.6+1.5)  

E-print Network

Observer, Kitt Peak National Observatory, National Optical Astronomy Observatories, operated by the Association of Universities for Research in Astronomy, Inc., under cooperative agreement with the National, Case Western Reserve University. 2 Also the Dominion Radio Astrophysical Observatory, Herzberg

302

Teaching and Learning Astronomy  

NASA Astrophysics Data System (ADS)

Preface; Part I. Astronomy in the Curriculum Around the World: Preface; 1. Why astronomy is useful and should be included in the school curriculum John R. Percy; 2. Astronomy and mathematics education Rosa M. Ros; 3. Astronomy in the curriculum around the world; 4. Engaging gifted science students through astronomy Robert Hollow; 5. Poster highlights: astronomy in the curriculum around the world; Part II. Astronomy Education Research: Preface; 6. Astronomy education research down under John M. Broadfoot and Ian S. Ginns; 7. A contemporary review of K-16 astronomy education research Janelle M. Bailey and Timothy F. Slater; 8. Implementing astronomy education research Leonarda Fucili; 9. The Astronomy Education Review: report on a new journal Sidney C. Wolff and Andrew Fraknoi; 10. Poster highlights: astronomy education research; Part III. Educating Students: Preface; 11. Textbooks for K-12 astronomy Jay M. Pasachoff; 12. Distance/internet astronomy education David H. McKinnon; 13. Educating students with robotic telescopes - open discussion; 14. Poster highlights - educating students; Part IV. Educating teachers: Preface; 15. Pre-service astronomy education of teachers Mary Kay Hemenway; 16. In-service education of teachers Michle Gerbaldi; 17. Poster highlights: educating teachers; Part V. Astronomy and Pseudoscience: Preface; 18. Astronomy, pseudoscience and rational thinking Jayant V. Narlikar; 19. Astronomical pseudosciences in North America John R. Percy and Jay M. Pasachoff; Part VI. Astronomy and Culture: Preface; 20. Teaching astronomy in other cultures: archeoastronomy Julieta Fierro; 21. Poster highlights: astronomy and culture; Part VII. Astronomy in Developing Countries: Preface; 22. Astronomy Curriculum for developing countries Case Rijsdijk; 23. Science education resources for the developing countries James C. White II; Part VIII. Public Outreach in Astronomy: Preface; 24. What makes informal education programs successful? Nahide Craig and Isabel Hawkins; 25. The role of science centers and planetariums Nick Lomb; 26. Science education for the new century - a European perspective Claus Madsen; 27. Communicating astronomy to the public Charles Blue; 28. Poster highlights: public outreach in astronomy; Part IX. The Education Programs of the IAU: Preface; 29. A short overview of astronomical education carried out by the IAU Syuzo Isobe; Part X. Discussion; Index.

Pasachoff, Jay; Percy, John

2009-07-01

303

Teaching and Learning Astronomy  

NASA Astrophysics Data System (ADS)

Preface; Part I. Astronomy in the Curriculum Around the World: Preface; 1. Why astronomy is useful and should be included in the school curriculum John R. Percy; 2. Astronomy and mathematics education Rosa M. Ros; 3. Astronomy in the curriculum around the world; 4. Engaging gifted science students through astronomy Robert Hollow; 5. Poster highlights: astronomy in the curriculum around the world; Part II. Astronomy Education Research: Preface; 6. Astronomy education research down under John M. Broadfoot and Ian S. Ginns; 7. A contemporary review of K-16 astronomy education research Janelle M. Bailey and Timothy F. Slater; 8. Implementing astronomy education research Leonarda Fucili; 9. The Astronomy Education Review: report on a new journal Sidney C. Wolff and Andrew Fraknoi; 10. Poster highlights: astronomy education research; Part III. Educating Students: Preface; 11. Textbooks for K-12 astronomy Jay M. Pasachoff; 12. Distance/internet astronomy education David H. McKinnon; 13. Educating students with robotic telescopes - open discussion; 14. Poster highlights - educating students; Part IV. Educating teachers: Preface; 15. Pre-service astronomy education of teachers Mary Kay Hemenway; 16. In-service education of teachers Michle Gerbaldi; 17. Poster highlights: educating teachers; Part V. Astronomy and Pseudoscience: Preface; 18. Astronomy, pseudoscience and rational thinking Jayant V. Narlikar; 19. Astronomical pseudosciences in North America John R. Percy and Jay M. Pasachoff; Part VI. Astronomy and Culture: Preface; 20. Teaching astronomy in other cultures: archeoastronomy Julieta Fierro; 21. Poster highlights: astronomy and culture; Part VII. Astronomy in Developing Countries: Preface; 22. Astronomy Curriculum for developing countries Case Rijsdijk; 23. Science education resources for the developing countries James C. White II; Part VIII. Public Outreach in Astronomy: Preface; 24. What makes informal education programs successful? Nahide Craig and Isabel Hawkins; 25. The role of science centers and planetariums Nick Lomb; 26. Science education for the new century - a European perspective Claus Madsen; 27. Communicating astronomy to the public Charles Blue; 28. Poster highlights: public outreach in astronomy; Part IX. The Education Programs of the IAU: Preface; 29. A short overview of astronomical education carried out by the IAU Syuzo Isobe; Part X. Discussion; Index.

Pasachoff, Jay; Percy, John

2005-12-01

304

PROPOSED PORTHOLE FOR ASTRONOMY MAJORS Information for Astronomy Majors  

E-print Network

PROPOSED PORTHOLE FOR ASTRONOMY MAJORS Information for Astronomy Majors The Astronomy Major sciences such as Astronomy, Physics, or Engineering. (Link to details on Astrophysics Concentration) The General Astronomy Concentration is intended for students who do not plan on research careers in astronomy

Richardson Jr., James E.

305

Saturn's variable radio period  

NASA Astrophysics Data System (ADS)

Latest SKR measurements by Cassini/RPWS confirm the observed, slow and regular increase of its rotational modulation period ( 10.9 hr), at the scale of about 0.5 percent over the last three years. In the meantime, similar drifts could also be found in some other observed magnetospheric phenomena (e.g. magnetic field, UV auroras, etc. . . ), indicating that the inner magnetosphere of Saturn is globally changing at the 30-year scale of its revolution around the Sun. In order to better assess the possible causes of the observed variation, the whole Cassini radio astronomy data set is reexamined, and compared to the long lasting (1991-2007) Saturn's SKR monitoring by the Ulysses/URAP radio astronomy instrument.

Lecacheux, Alain

306

A Large-Scale Jet and FR I Radio Source in a Spiral Galaxy: The Host Properties and External Environment  

E-print Network

. Yun 2 National Radio Astronomy Observatory 3 , Socorro, NM 87801 and John M. Hill Steward Observatory Department, University of Massachusetts, Amherst, MA 01003 3 The National Radio Astronomy Observatory is operA Large-Scale Jet and FR I Radio Source in a Spiral Galaxy: The Host Properties and External

307

The Sardinia Radio Telescope  

NASA Astrophysics Data System (ADS)

We present the status of the Sardinia Radio Telescope (SRT) project, a new general purpose, fully steerable 64 m diameter parabolic radio telescope under construction in Sardinia. The instrument is funded by Italian Ministry of University and Research (MIUR), by the Sardinia Regional Government (RAS), and by the Italian Space Agency (ASI), and it is charge to three research structures of the National Institute for Astrophysics (INAF): the Institute of Radio Astronomy of Bologna, the Cagliari Astronomical Observatory (in Sardinia), and the Arcetri Astrophysical Observatory in Florence. The radio telescope has a shaped Gregorian optical configuration with a 8 m diameter secondary mirror and additional Beam-Wave Guide (BWG) mirrors. One of the most challenging feature of SRT is the active surface of the primary reflector which provides good efficiency up to about 100 GHz. This paper reports on the most recent advances of the construction.

D'Amico, Nichi

2011-08-01

308

Observatory Publishes Memoir of Pioneer Radio Astronomer  

NASA Astrophysics Data System (ADS)

One of the pioneers of radio astronomy tells her story of the formative years of that science in a memoir published by the National Radio Astronomy Observatory. Dr. Nan Dieter Conklin's book, Two Paths to Heaven's Gate, recounts her experiences making important scientific discoveries in an era when astronomy's "vision" was first extending beyond the light discernable to human eyes. Book Cover CREDIT: NRAO/AUI/NSF Conklin's story is remarkable not only because of her impressive scientific achievements, but also "because she was a woman who nevertheless pursued and succeeded in science -- the first U.S. woman whose Ph.D. thesis was based on her own radio astronomy research and the first U.S. woman to publish original radio astronomy research in a refereed journal -- and because she lived and worked with the degenerative disease multiple sclerosis," according to Claire Hooker of the University of Toronto. In the memoir, Conklin recounts her career and life from the awakening stirred by her first astronomy course at Goucher College in Baltimore, to junior research jobs in Washington, D.C., to graduate school at Harvard and ultimately to the faculty of the University of California at Berkeley. In addition to providing an insider's view of the process of scientific discovery, Conklin also gives the reader a fascinating look at a scientific community and social structure that, though only a half-century removed from the present, was vastly different from today's. Along the way, Conklin candidly reveals the person behind the science -- the person who dealt with the joys and tragedies of life while remaining dedicated to unlocking the secrets of the Universe. "Nan was and remains an inspiration to myself and hundreds of others in the field, both for her scientific acumen and for her ability to overcome extraordinary personal challenges," said Miller Goss of the National Radio Astronomy Observatory. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

2006-07-01

309

Radio Telescope Gets Star Treatment  

NASA Astrophysics Data System (ADS)

Actress Jodie Foster, who played a scientist in search of extraterrestrial life in the 1997 film Contact, narrates a new promotional film to reintroduce the public to the National Radio Astronomy Observatory's (NRAO) renovated Karl G. Jansky Very Large Array (VLA) radio telescope in New Mexico. The 24-minute film, Beyond the Visible, which will air in the VLA Visitor Center, focuses on the operation of the telescope and scientific achievements associated with it.

Showstack, Randy

2013-11-01

310

Nontechnical Astronomy Books of 1989.  

ERIC Educational Resources Information Center

Presented are 126 reviews. Categories include amateur astronomy, children's books, computers and astronomy, cosmic rays, cosmology, education in astronomy, galaxies, general astronomy, history of astronomy, life in the universe, physics and astronomy, pseudoscience, quasars and active galaxies, reference, solar system, space exploration, stars and

Mercury, 1990

1990-01-01

311

The Radio Jove Project  

NASA Technical Reports Server (NTRS)

The Radio love Project is a hands-on education and outreach project in which students, or any other interested individuals or groups build a radio telescope from a kit, operate the radio telescope, transmit the resulting signals through the internet if desired, analyze the results, and share the results with others through archives or general discussions among the observers. Radio love is intended to provide an introduction to radio astronomy for the observer. The equipment allows the user to observe radio signals from Jupiter, the Sun, the galaxy, and Earth-based radiation both natural and man-made. The project was started through a NASA Director's Discretionary Fund grant more than ten years ago. it has continued to be carried out through the dedicated efforts of a group of mainly volunteers. Dearly 1500 kits have been distributed throughout the world. Participation can also be done without building a kit. Pre-built kits are available. Users can also monitor remote radio telescopes through the internet using free downloadable software available through the radiosky.com website. There have been many stories of prize-winning projects, inspirational results, collaborative efforts, etc. We continue to build the community of observers and are always open to new thoughts about how to inspire the observers to still greater involvement in the science and technology associated with Radio Jove.

Thieman, J. R.

2010-01-01

312

Radio Galaxies.  

ERIC Educational Resources Information Center

Provides background information on radio galaxies. Topic areas addressed include: what produces the radio emission; radio telescopes; locating radio galaxies; how distances to radio galaxies are found; physics of radio galaxies; computer simulations of radio galaxies; and the evolution of radio galaxies with cosmic time. (JN)

Downes, Ann

1986-01-01

313

Neutrino astronomy  

SciTech Connect

Current knowledge and proposed experiments in the field of neutrino astronomy are reviewed, with particular emphasis on expected sources and existing and proposed detectors for intermediate-energy (10 to 50 MeV) and ultrahigh energy (greater than 10 GeV) neutrinos. Following a brief discussion of the counting rate obtained in the solar neutrino experiment of Davis (1978) and possible statistical sources for the discrepancy between the expected and observed rates, consideration is given to the physics of neutrino ejection in stellar gravitational collapse and sources of high-energy proton collisions giving rise to ultrahigh energy neutrinos. The capabilities of operating Cerenkov detectors at the Homestake Gold Mine, the Mt. Blanc Tunnel and in the Soviet Caucasus are considered in relation to the detection of gravitational collapse in the center of the galaxy, and it is pointed out that neutrino detectors offer a more reliable means of detecting collapses in the Galaxy than do gravitational wave detectors. The possibility of using Cerenkov detectors for ultrahigh energy neutrino detection is also indicated, and applications of large neutrino detectors such as the proposed DUMAND array to measure the lifetime of the proton are discussed.

Schramm, D.N.

1980-01-01

314

Astronomy Links  

NSDL National Science Digital Library

Here are some links to Astronomy applets, animations, and movies. Celestial and Terrestrial Motions Sky and telescope Interactive Sky Chart Rotating Sky Explorer Ecliptic (Zodiac) Simulator Seasonal Solar Motions Antarctica Time Lapse: A Year on Ice Aurora Australis: The Southern Lights [Daylight Hours Explorer Season as viewed from Space Animation Sun Position and Season animation Paths of the Sun Seasons and Ecliptic Simulator Sun s Rays Simulator Sun Motions Simulator Time-Lapse Seasons Simulator Kepler's Laws of Planetary Motion Kepler s 1st and 2nd laws Applet Orbit Applet Planetary Orbit Simulator Gravity Simulator Moon Phases and Satellite Motions Lunar and Solar Eclipse Information Moon Phase Animation What Causes Tides Lunar Phase Quizzer Eclipse Shadow Simulator Moon Phases and the Horizon Diagram Synodic Lag The Solar System Solar and Heliospheric Observatory (SOHO) Images Planetary Photo Journal Planetary Configuration Simulator Geocentric Retrograde Motion Animation Epicycle / Orbit Applet Gravity Simulator Ptolemaic Orbit of Mars The Universe Virtual Reality Milky Way Panorama Interactive H-R Diagram Element Absorption and Emision Lines Doppler Shift Demonstrator Lookback Time Simulator Other: SpaceWeather.com ...

Teitelbaum, Mr.

2010-11-18

315

IUCAF and spectrum management: working to keep our radio windows on the Universe clean  

Microsoft Academic Search

The brief of IUCAF (the Scientific Committee on Frequency Allocations for Radio Astronomy and Space Science - see www.iucaf.org) is to study and coordinate the requirements of radio frequency allocations for passive (i.e., non-emitting) radio sciences, such as radio astronomy, space research and remote sensing, in order to make these requirements known to the national and international bodies that allocate

Wim van Driel

2008-01-01

316

Interstellar Radio Communication and the Frequency Selection Problem  

Microsoft Academic Search

THE largest microwave radio telescope on Earth, at the Arecibo Observatory of the National Astronomy and Ionosphere Center, will soon have the capability of communicating with an identical radio telescope, if such exists, anywhere in the Galaxy. But such communication assumes some previous agreement between the transmitting and receiving civilizations, or mutual discovery of the chosen radio frequency, bandpass, information

F. D. Drake; Carl Sagan

1973-01-01

317

Radio detection of Uranian lightning by Voyager 2  

Microsoft Academic Search

Within distances of ?600,000 km from Uranus, the Planetary Radio Astronomy experiment aboard the Voyager 2 spacecraft detected impulsive (100 - 300 ms) bursts of broad-band (<=900 kHz to ?40 MHz) radio emission. This emission is very different from the uranian magnetospheric radio component, also discovered during the recent Voyager - Uranus encounter. By analogy with the Saturn electrostatic discharges

P. Zarka; B. M. Pedersen

1986-01-01

318

A Group Sparsity Imaging Algorithm for Transient Radio Sources  

E-print Network

://graphics.tu-bs.de/ Urvashi Rau National Radio Astronomy Observatory Socorro, NM 87801, USA httpA Group Sparsity Imaging Algorithm for Transient Radio Sources Stephan Wenger and Marcus Magnor://www.aoc.nrao.edu/rurvashi/ Abstract--Radio interferometers can achieve high spatial res- olution for temporally constant sources

Magnor, Marcus

319

Keeping our windows on the radio Universe clean  

Microsoft Academic Search

The radio spectrum is a finite and increasingly precious resource for astronomical research. Keep- ing the frequency bands used for radio astronomy as free as possible of unwanted Radio Fre- quency Interference (RFI) is crucial. The aim of spectrum management, one of the tools used towards achieving this goal, includes setting regulatory limits on RFI levels emitted by other spec-

Wim van Driel

320

Introductory Astronomy Clearinghouse Labs  

NSDL National Science Digital Library

This website from the University of Washington Department of Astronomy provides introductory astronomy activities on topics such as: fundamentals of astronomy, observing the sky, the sun, stars, stellar evolution, the H-R diagram, the Milky Way Galaxy, galaxies, and cosmology. Printable laboratory guides are available for download in Microsoft Word format.

2010-11-18

321

Radio jets in NGC 4151  

NASA Technical Reports Server (NTRS)

The relationship between the radio and optical emissions from the nucleus of the Seyfert galaxy NGC 4151 is investigated by mapping the radio radiation from this source at wavelengths of 20 and 6 cm using the Very Large Array of the National Radio Astronomy Observatory. Results show that the radio emission at wavelengths from 20 to 6 cm extend 10'' (950 pc) along a position angle of 72-84 degrees. This nonthermal emission is found to consist of at least six components and is similar to jets observed in other compact extragalactic radio sources. These radio jets appear to be coincident with the optical line emission region in NGC 4151 and are aligned with the position angle of the linearly polarized optical continuum emission.

Johnston, K. J.; Elvis, M.; Kjer, D.; Shen, B. S. P.

1982-01-01

322

November 20, 2012 A Volume Limited Radio Survey of Ultracool Dwarfs  

E-print Network

National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA 3 Department of Astronomy, University of California, Berkeley, CA 94720, USA 4 Armagh Observatory, College Hill, Armagh BT61 for Astronomy, National University of Ireland, Galway, Ireland 7 Price Center, Albert Einstein College

323

Tools of Radio Astronomy, 5th edition  

NASA Astrophysics Data System (ADS)

New 5th corrected edition of the book http://adsabs.harvard.edu/abs/2009tra..book.....W in Russian, translated by O. Verkhodanov and S. Trushkin, editing S.A. Trushkin from Special astrophysical observatory RAS. This edition contains the translation of the 5th Springer edition of 2009 and new additional chapter (wrote by authors) of Solutions of the problems.

Wilson, Thomas L.; Rohlfs, Kristian; Huttemeister, Susanne

2012-12-01

324

NATIONAL RADIO ASTRONOMY OBSERVATORY Charlottesville, Virginia  

E-print Network

= circuits using photo-etching methods developed by the Eastman Kodak Company 1 . Plating is performed in the baths listed below: Gold: (1) American Chemical and Refining Company, C-27 acid gold plate process manufactured by Ashland Chemical Corporation, Electropolish i6. 2.1 GOLD PLATING Gold is presently being

Groppi, Christopher

325

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLE, VIRGINIA  

E-print Network

temperatures, variations in the circuit can be made. For example, a resistor can be put in series OF COPIES: 150 #12;This report describes a circuit for the speed control of an electronic equipment cooling speed fans. The following sections briefly describe the circuit and include schematics and graphs

Groppi, Christopher

326

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLE VIRGINIA  

E-print Network

graphics and subroutine capabilities, a CRT display and paper printer, cassette storage, and a particularly;CONTENTS Page User's Manual for FARANT Introduction 1 Conventions 1 User's Commands 2 Frequency: Lumped Model of an PET 11 Detailed User Instructions The Reference Zo for S-Parameters 13 Creating

Groppi, Christopher

327

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLE VIRGINIA  

E-print Network

problems, graphics, and many other individual needs. For their guidance and continuing encouragement I must and instruction in microwave circuit design methods. #12;A COMPUTER-AIDED ANALYSIS ROUTINE INCLUDING OPTIMIZATION FOR MICROWAVE CIRCUITS AND THEIR NOISE Table of Contents Page I . User s Manual for FARANT

Groppi, Christopher

328

Meter wavelength radio astronomy in Chile  

Microsoft Academic Search

Current meter-wavelength research at Maipu consists largely of a galactic survey for the southern sky, a search for secondary calibration sources, pulsar studies, a search for atmospheric pulses from Saturn, and the continuing investigation of Jovian S bursts above 30 MHz.

J. May; F. Reyes; H. Alvarez; J. Aparici; T. Carr; J. Phillips; J. Levy; G. Lebo

1986-01-01

329

NP Stokes fields for radio astronomy  

E-print Network

The spin weighted spherical harmonic (SWSH) description of angular functions typically is associated with the Newman-Penrose (NP) null tetrad formalism. Recently the SWSH description, but not the NP formalism, has been used in the study of the polarization anisotropy of the cosmic microwave background. Here we relate this application of SWSHs to a description of electromagnetic radiation and polarization in the NP formalism. In particular we introduce NP Stokes fields that are the NP equivalent of the Stokes parameters. In addition to giving a more coherent foundation for the recent cosmological SWSH application, the NP formalism aids in the computation of the Lorentz transformation properties of polarization.

Ezra T. Newman; Richard H. Price

2010-07-25

330

Rapid Development of Radio Astronomy Instrumentation  

E-print Network

, PFBs, DDC) Implement Industry Standard Communication Protocols (10 Gb Ethernet, UDP) Platform of Custom Boards, Backplanes and Protocols Antiquated by the Time of Release Each Observatory Designs From

California at Berkeley, University of

331

National Radio Astronomy Observatory Socorro, NM 87801  

E-print Network

that these cables experience are lightning, flood damage, backhoe damage, and gopher damage. The lightning damage to replace cable due to gopher damage or armor corrosion. In a telephone conversation with a recently retired

Groppi, Christopher

332

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLEJ VIRGINIA  

E-print Network

Amplifier Without Coaxial Components · · · · · · · · . 8 Figure 5 Coaxial Components . · . · · · · · · · . 8), and a SMA to waveguide adaptor as shown in Figure 1. This configuration is designed to easily fit that better reliability would be achieved with packaged devices. 2) A coaxial geometry with a round center

Groppi, Christopher

333

Graphical Processing Units (GPUs) in Radio Astronomy  

E-print Network

-chip" memory Fast Small (~16 kB / thread block) "Off-chip" Slow Large (~GB) #12;Memory management Optimizing elements of FPGAs, GPUs, and CPUs, each with different strengths/uses: FPGA ­ High data rate; small memory

Groppi, Christopher

334

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLE VIRGINIA  

E-print Network

No. 248 ANALOG-FILTER, DIGITAL-CORRELATOR HYBRID SPECTROMETER SANDER WEINREB JUNE 1984 NUMBER of the hybrid system is shown to be much lower than the cost of spectrometers which utilize either a filter Selection · · · · · 0 · · · · · · · · · · · · · · · · . . · · · · · · · · · B. VHF Bandpass Filter-Mixer

Groppi, Christopher

335

NATIONAL RADIO ASTRONOMY OBSERVATORY Charlottesville, Virginia 22903  

E-print Network

amplifier applies also to balanced mixers based on quadrature hybrids. Introduction The balanced amplifier quadrature hybrids, and of a mismatched output load, but did not explore the effect of a mismatched source

Groppi, Christopher

336

NATIONAL RADIO ASTRONOMY OBSERVATORY CHARLOTTESVILLE, VIRGINIA  

E-print Network

- diode mixers, bandwidth will be limited by the ow-noise IF amplifier. At present, the amplifier utilized], [4] as 3dB hybrid is utilized. This choice is superior to a single-ended amplifier with an isolator identical, sirgle -- ended amplifiers in cascade with a 3dB hybrid was studied in detail by K. Kurokawa [2

Groppi, Christopher

337

National Radio Astronomy Observatory (NRAO), Tucson  

Microsoft Academic Search

One of the radioastronomy facilities funded by the US National Science Foundation, and operated under cooperative agreement by Associated Universities, Incorporated. Located in Tucson on the campus of the University of Arizona....

P. Murdin

2000-01-01

338

Conducting radio astronomy in the EMC environment  

NASA Astrophysics Data System (ADS)

The detection of electromagnetic interference (EMI) at microwave frequencies, examples of the widely varying sources of such EMI, and measures to counteract them are considered. Problems caused by computer equipment, power lines, digital clocks, automotive spark plugs, television antennas, arc welding equipment, phone systems, aircraft transmissions, and satellite equipment are described. Countermeasures include the use of braided mesh around cables, burying of incoming power lines, and replacement of defective equipment. Certain antenna radome structures are particularly helpful in countering EMI.

Waterman, P. J.

1984-02-01

339

Using large radio telescopes at decametre wavelengths  

Microsoft Academic Search

With the aim of evaluating the actual possibilities of doing, from the ground, sensitive radio astronomy at decametre wavelengths (particularly below ?50MHz), an extensive program of radio observations was carried out, in 19992002, by using digital spectral and waveform analysers (DSP) of new generation, connected to several of the largest, decametre radio telescopes in the world (i.e., the UTR-2 and

A. Lecacheux; A. A. Konovalenko; H. O. Rucker

2004-01-01

340

A Voyage through the Radio Universe  

NSDL National Science Digital Library

The Radio Astronomy Research Team from from Oil City Area Senior High School (OCHS) in Oil City, Pennsylvania, embarked on a special project titled "Mapping the Universe" at the start of the 2000 school year. For the project, students analyzed data from the Arecibo Radio Telescope, which is the world's largest single dish radio telescope, in an effort to learn more about distant galaxies. Students used the information they gathered to calculate the Hubble constant--an accomplishment usually achieved by professional astronomers.

Spuck, Timothy

2004-10-01

341

African Astronomy and the Square Kilometre Array  

NASA Astrophysics Data System (ADS)

We highlight the growth of astronomy across Africa and the effect of hosting the Square Kilometer Array (SKA) will have on this growth. From the construction of a new 25m radio telescope in Nigeria, to new university astronomy programmes in Kenya, the HESS in Namibia and the Mauritian Radio Telescope, to the world class projects being developed in South Africa (Southern African Large Telescope and Karoo Array Telescope) astronomy is re-emerging across the continent. The SKA will represent the pinnacle of technological advancement in astronomy when constructed; requiring ultra high speed data transmission lines over 3000 km baselines and the World's fastest computer for correlation purposes. The investment alone to build the SKA on African soil will be of great economic benefit to its people, but the required network connectivity will significantly drive commercial expansion far beyond the initial value of the SKA investment. The most important consequence of hosting the SKA in Africa would be the impact on Human Capital Development (HCD) on the continent. Major HCD projects already underway producing excellent results will be presented. )

MacLeod, Gordon

2010-02-01

342

Astronomy and Politics  

NASA Astrophysics Data System (ADS)

The relationship between astronomy and politics is a complex but important part of understanding the practice of astronomy throughout history. This chapter explores some of the ways that astronomy, astrology, and politics have interacted, placing particular focus on the way that astronomy and astrology have been used for political purposes by both people in power and people who wish to influence a ruler's policy. Also discussed are the effects that politics has had on the development of astronomy and, in particular, upon the recording and preservation of astronomical knowledge.

Steele, John M.

343

Deterministic RF ing in phased arrays for the next generation of radio telescopes  

Microsoft Academic Search

A requirement of the next generation of radio telescopes for astronomy is the ability to cope with the forever increasing problem of radio-frequency interference (RFI). Unlike conventional fixed parabolic receivers, currently used in astronomy, the application of phased-array beamforming techniques opens up the possibility to spatially RFI in the RF domain, prior to signal digitization. This paper presents results from

Bart Smolders; Grant Hampson

2002-01-01

344

David Tsiklauri, Astronomy Unit, School of Physics and Astronomy  

E-print Network

David Tsiklauri, Astronomy Unit, School of Physics and Astronomy astro.qmul.ac.uk/~tsiklauri 19 Sep oscillations, waves in magnetised plasmas, elements of plasma kinetics. David Tsiklauri Astronomy Unit Queen, Astronomy Unit, School of Physics and Astronomy astro.qmul.ac.uk/~tsiklauri 19 Sep 2012 STFC summer school

345

Ph.D. Astronomy Program Ph.D. in Astronomy  

E-print Network

Ph.D. Astronomy Program Ph.D. in Astronomy Department(s) Physics and Astronomy College Sciences 1 physics at the graduate level 4. understand observational astronomy techniques 5. understand astrophysics strong background of knowledge and expertise in physics and astronomy #12;2. Curriculum Alignment

Hemmers, Oliver

346

M.S. Astronomy Program M.S. in Astronomy  

E-print Network

M.S. Astronomy Program M.S. in Astronomy Department(s) Physics and Astronomy College Sciences 1 for later reference. 1. understanding of a variety of fields of physics and astronomy at the graduate level 2*. performance of an astronomy research project suitable for a masters thesis 3*. ability

Hemmers, Oliver

347

Investigation of radio astronomical windows between 1 MHz and 2060 MHz in Universiti Malaya, Malaysia  

Microsoft Academic Search

An indoor and an outdoor radio frequency survey was conducted in Universiti Malaya, Malaysia, as a test site, for the purpose of developing radio astronomy research in Malaysia. This is the first radio astronomical survey of any such done in Malaysia. Observation and analysis were done in the radio frequency spectrum between 1MHz and 2060MHz. In this paper, the experimental

Zamri Zainal Abidin; Zainol Abidin Ibrahim; Syed Bahari Ramadzan Syed Adnan; Norwati Khairul Anuar

2009-01-01

348

Investigation of radio astronomical windows between 1 MHz and 2060 MHz in Universiti Malaya, Malaysia  

Microsoft Academic Search

An indoor and an outdoor radio frequency survey was conducted in Universiti Malaya, Malaysia, as a test site, for the purpose of developing radio astronomy research in Malaysia. This is the first radio astronomical survey of any such done in Malaysia. Observation and analysis were done in the radio frequency spectrum between 1 MHz and 2060 MHz. In this paper,

Zamri Zainal Abidin; Zainol Abidin Ibrahim; Syed Bahari Ramadzan Syed Adnan; Norwati Khairul Anuar

2009-01-01

349

The road to the Radio Synoptic SKA (RSSKA) Steven T. Myers  

E-print Network

has been proposed for a Radio Synoptic Survey Telescope (RSST) 3 . A RSST would be designed to survey the next generation of radio astronomical telescopes and arrays. One of the original drivers for the SKAThe road to the Radio Synoptic SKA (RSSKA) Steven T. Myers National Radio Astronomy Observatory, P

Myers, Steven T.

350

ASTRONOMY AND ASTROLOGY IN THE  

E-print Network

ASTRONOMY AND ASTROLOGY IN THE WORKS OF CHAUCER Done By: Ameerah Bte Po'ad Mattar Chew Yoke Wah in astronomy albeit the astronomy incorporated in his works are concealed in a way that it is difficult to extract his full knowledge of astronomy. Astronomy was not the key topic in Chaucer's works although his

Aslaksen, Helmer

351

"Conference on communicating astronomy with the public":taking action  

NASA Astrophysics Data System (ADS)

In October 2003, The National Radio Astronomy Observatories (NRAO) and the National Research Council (NRC) held a three-day conference in Washington, D.C., on communicating with the public about astronomy. The goals of this conference, intended to be a working meeting, were 'to develop a program to share outreach and education resources among the astronomical community [and] to find ways of communicating with underdeveloped constituencies.' Scientists, communication specialists and others active in public outreach and education about astronomy and space science deliberated on the current state of astronomy communications, the needs of the mass media and the entertainment media, the conduct of public outreach and education as an element of research astronomy, and best practices in astronomy outreach and education. Two important products of the meeting were: 1) A 'Washington charter for communicating astronomy with the public,' a position paper articulating principles of action for funding agencies, professional astronomical societies, individual researchers and universities, laboratories, research organizations and other institutions interested in communicating with the public about astronomy; 2) The appointment of a task force to to organize an electronic archive of informational resources about astronomy. Two options under consideration by the task force are creation of a Web site providing links, categorized and searchable, to astronomy public outreach and education resources; and creation of a Web site that would be a searchable database of astronomy information and imagery (either representative or comprehensive). This paper will highlight the proceedings of the conference, report outcomes, and provide a status report on post-conference actions.

Billings, L.

352

Some innovative programmes in Astronomy education  

NASA Astrophysics Data System (ADS)

In order to inculcate a systematic scientific awareness of the subject of Astronomy among the students and to motivate them to pursue careers in Astronomy and Astrophysics, various innovative educational programmes have been designed at MPBIFR. Among them, the main programme is termed as the ``100-hour Certificate Course in Astronomy and Astrophysics'' which has been designed basically for the students of the undergraduate level of B.Sc. and B.E. streams. The time duration of the 100 hours in this course is partitioned as 36 hours of classroom lectures, 34 hours of practicals and field trips and the remaining 30 hours being dedicated to dissertation writing and seminar presentations by the students. In addition, after the 100-hour course, the students have the option to take up specialized advance courses in the topics of Astrobiology, Astrochemistry, Radio Astronomy, Solar Astronomy and Cosmology as week-end classes. These courses are at the post graduate level and are covered in a span of 18 to 20 hours spread over a period of 9 to 10 weeks. As a preparatory programme, short-term introductory courses in the same subject are conducted for the high school students during the summer vacation period. Along with this, a three-week programme in basic Astronomy is also designed as an educational package for the general public. The students of these courses have the opportunity of being taken on field trips to various astronomical centers as well as the Radio, Solar and the Optical Observatories as part of their curriculum. The guided trips to the ISROs Satellite Centre at Bangalore and the Satellite Launching Station at SHAR provide high degree of motivation apart from giving thrilling experiences to the students. Further, the motivated students are encouraged to involve themselves in regular research programmes in Astronomy at MPBIFR for publishing research papers in national and international journals. The teaching and mentoring faculty for all these programmes includes the visiting Scientists and Professors from various Research Organizations located in and around Bangalore as well as the in-house Scientific staff. It is gratifying to note that several students, after going through one or more of these courses, have indeed made commitments to pursue Astronomy as their career, some of them even obtaining admissions in to the institutes and universities in India and abroad for further studies in this field.

Babu, G. S. D.; Sujatha, S.

353

PHYSICS & ASTRONOMY GRADUATE STUDENT HANDBOOK DEPARTMENT OF PHYSICS & ASTRONOMY  

E-print Network

PHYSICS & ASTRONOMY GRADUATE STUDENT HANDBOOK DEPARTMENT OF PHYSICS & ASTRONOMY UNIVERSITY OF UTAH Fall 2012 Version 2012 .................................................................................... 11 3.1. Ph.D. in Physics 12 3.1.1. Astronomy & Astrophysics

Tipple, Brett

354

The Radio Sky in the STARLAB  

NASA Astrophysics Data System (ADS)

The STARLAB is a portable planetarium created, produced, and distributed by Learning Technologies, Ltd. Upon entering the STARLAB, images are projected onto the ceiling of the planetarium's dome using custom, interchangeable projection cylinders mounted on top of an ultrabright point light source. The STARLAB is ideal for teaching students about astronomy since it may be easily transported to schools across the nation. In order to take advantage of this powerful teaching tool, one of the foremost priorities of the Sensing the Radio Sky project was the development a projection cylinder that would visually interpret the quantitative data taken with radio telescopes and present that information in a form that students could understand and appreciate. The final version of the cylinder demonstrates a variety of topics relevant to an understanding of radio astronomy. When using the Radio Sky cylinder in the STARLAB, teachers may discuss the differences between optical and radio astronomy such as the structure of the Milky Way Galaxy, different sources of electromagnetic radiation, and important radio sources within and outside of the Galaxy. In addition, the flexibility of the cylinder's design allows for a variety of educational activities to be conducted within the STARLAB, all complemented by the Radio Sky cylinder's unique presentation of the Galaxy in radio wavelengths. We acknowledge support from the NSF Internship in Public Science Education Program grant number 0324729.

Fultz, C.; Smith, T.; Buck, S.; Harris, R.; Boltuch, D.; Hund, L.; Moffett, D.; Walsh, L.; LaFratta, M.; Castelaz, M. W.

2005-12-01

355

The Old Astronomy  

NSDL National Science Digital Library

This series of webpages is part of a course, called Astronomy 161: The Solar System, offered by the Department of Physics and Astronomy at the University of Tennessee. This section covers the view of the universe that astronomers held up to 500 years ago, including: the apparent motion of the planets (such as retrograde motion) on the celestial sphere; the universe of Ptolemy and Aristotle, involving epicycles; and medieval Aristotelian astronomy.

2007-01-17

356

Information Content in Radio Waves: Student Investigations in Radio Science  

NASA Astrophysics Data System (ADS)

We describe an inquiry-based instructional unit on information content in radio waves, created in the summer of 2013 as part of a MIT Haystack Observatory (Westford, MA) NSF Research Experiences for Teachers (RET) program. This topic is current and highly relevant, addressing science and technical aspects from radio astronomy, geodesy, and atmospheric research areas as well as Next Generation Science Standards (NGSS). Projects and activities range from simple classroom demonstrations and group investigations, to long term research projects incorporating data acquisition from both student-built instrumentation as well as online databases. Each of the core lessons is applied to one of the primary research centers at Haystack through an inquiry project that builds on previously developed units through the MIT Haystack RET program. In radio astronomy, students investigate the application of a simple and inexpensive software defined radio chip (RTL-SDR) for use in systems implementing a small and very small radio telescope (SRT and VSRT). Both of these systems allow students to explore fundamental principles of radio waves and interferometry as applied to radio astronomy. In ionospheric research, students track solar storms from the initial coronal mass ejection (using Solar Dynamics Observatory images) to the resulting variability in total electron density concentrations using data from the community standard Madrigal distributed database system maintained by MIT Haystack. Finally, students get to explore very long-baseline interferometry as it is used in geodetic studies by measuring crustal plate displacements over time. Alignment to NextGen standards is provided for each lesson and activity with emphasis on HS-PS4 'Waves and Their Applications in Technologies for Information Transfer'.

Jacobs, K.; Scaduto, T.

2013-12-01

357

Random time series in astronomy.  

PubMed

Progress in astronomy comes from interpreting the signals encoded in the light received from distant objects: the distribution of light over the sky (images), over photon wavelength (spectrum), over polarization angle and over time (usually called light curves by astronomers). In the time domain, we see transient events such as supernovae, gamma-ray bursts and other powerful explosions; we see periodic phenomena such as the orbits of planets around nearby stars, radio pulsars and pulsations of stars in nearby galaxies; and we see persistent aperiodic variations ('noise') from powerful systems such as accreting black holes. I review just a few of the recent and future challenges in the burgeoning area of time domain astrophysics, with particular attention to persistently variable sources, the recovery of reliable noise power spectra from sparsely sampled time series, higher order properties of accreting black holes, and time delays and correlations in multi-variate time series. PMID:23277606

Vaughan, Simon

2013-02-13

358

Multiversos: Rock'n'Astronomy  

NASA Astrophysics Data System (ADS)

Imagine that you can use your fingers only for typing target coordinates at thetelescope, reduce images and spectra with IRAF, or write papers for Astronomy &Astrophysics, but you would never be able to play an electric guitar.Imagine that you love music, work in front of the computer always withheadphones, and dream of playing with your favourite rock band in a tumultuousconcert.Imagine that you are an astronomer who, after a "cosmic fluke", share stagewith the band which themes you have always hummed since you were a teenager.Imagine that you were born for rock, played a main role in the best Spanishalbum of the 90s (Omega, with Enrique Morente), and your songs arerutinary played by Radio 3, but you would never be able to detect an exoplanetor a galaxy at a high redshift.Imagine that you love Astronomy, try to see the Moon craters and Andromeda withyour small telescope through the light pollution of your city, and explain yourdaughter that Pluto is not a planet any longer. Imagine that you are a musician who, after a "cosmic fluke", give a talk justafter a Nobel laureate that discovered the cosmic microwave backgroundradiation.Such "cosmic flukes" sometimes happen. If you were not at the dinner of the SEA meeting and do not believe us, visithttp://www.myspace.com/antonioariasmultiverso or open the proceedings DVD andlisten "El ordenador simula el nacimiento de las estrella...".

Caballero, J. A.; Arias, A.; Garca, N.

2011-11-01

359

Environmental Issues and Astronomy: An Introductory Resource Guide  

NSDL National Science Digital Library

This site provides an introduction to the topic of environmental issues in respect to astronomy. A number of related readings and links to web sites are provided. Content includes information on light pollution, observatory sites and their environmental impact, radio interference and preventing the contamination of Earth or other worlds.

Fraknoi, Andrew

360

Astronomy Books for Adults  

NSDL National Science Digital Library

This reference list has more than 20 recommended astronomy books for older students and adults. For each title, the publisher and publication date is included, along with author name. The list is divided into three subcategories: General Astronomy and Astrophysics, Light and Telescopes, and Digital Imaging and the 3-D Universe.

361

High Energy Astronomy Observatory  

NASA Technical Reports Server (NTRS)

An overview of the High Energy Astronomy Observatory 2 contributions to X-ray astronomy is presented along with a brief description of the satellite and onboard telescope. Observations relating to galaxies and galactic clusters, black holes, supernova remnants, quasars, and cosmology are discussed.

1980-01-01

362

Extreme Ultraviolet Astronomy  

Microsoft Academic Search

This book describes the development of astronomy in the Extreme Ultraviolet (EUV) wavelength range, from the first rocket-based experiments in the late 1960s through to the latest satellite missions. It provides detailed material on the tools of EUV astronomy, dealing with the instrumentation, observational techniques, and modelling tools for the interpretation of data. Prospects for future EUV missions are discussed,

Martin A. Barstow; Jay B. Holberg

2003-01-01

363

Astronomy and Culture  

NASA Astrophysics Data System (ADS)

Astronomy is, by definition, the sum of the material and spiritual values created by mankind and of the institutions necessary to communicate these values. Consequently, astronomy belongs to the culture of each society and its scientific progress does nothing but underline its role in culture. It is interesting that there is even a European society which bears this name "Astronomy for Culture" (SEAC). Its main goal is "the study of calendric and astronomical aspects of culture". Owning ancient evidence of astronomical knowledge, dating from the dawn of the first millennium, Romania is interested in this topic. But Astronomy has a much deeper role in culture and civilization. There are many aspects that deserve to be discussed. Examples? The progress of astronomy in a certain society, in connection with its evolution; the place held by the astronomy in literature and, generally, in art; the role of the SF in the epoch of super-mediatization; astronomy and belief; astronomy and astrology in the modern society, and so forth. These are problems that can be of interest for IAU, but the most important one could be her educational role, in the formation of the culture of the new generation, in the education of the population for the protection of our planet, in the ensuring of a high level of spiritual development of the society in the present epoch.

Stavinschi, M.

2006-08-01

364

Astronomy Without a Telescope  

NSDL National Science Digital Library

Astronomy notes is an educational resource for introductory astronomy classes for undergraduates. This section describes: the celestial sphere, coordinate systems, the motion of the stars. There are also sections describing: time, the seasons, time zones, the phases of the moon, solar eclipses, lunar eclipses, and the motions of the planets.

Strobel, Nick

2004-07-16

365

Junior High Astronomy.  

ERIC Educational Resources Information Center

Selected materials needed to teach an astronomy unit as well as suggested procedures, activities, ideas, and astronomy fact sheets published by the Manitoba Planetarium are provided. Subjects of the fact sheets include: publications and classroom picture sets available from the National Aeronautics and Space Administration and facts and statistics

Greenstone, Sid; Smith, Murray

366

High energy particle astronomy.  

NASA Technical Reports Server (NTRS)

Discussion of techniques currently used in high energy particle astronomy for measuring charged and neutral cosmic rays and their isotope and momentum distribution. Derived from methods developed for accelerator experiments in particle physics, these techniques help perform important particle astronomy experiments pertaining to nuclear cosmic ray and gamma ray research, electron and position probes, and antimatter searches.

Buffington, A.; Muller, R. A.; Smith, L. H.; Smoot, G. F.

1972-01-01

367

Astronomy Demonstrations and Models.  

ERIC Educational Resources Information Center

Demonstrations in astronomy classes seem to be more necessary than in physics classes for three reasons. First, many of the events are very large scale and impossibly remote from human senses. Secondly, while physics courses use discussions of one- and two-dimensional motion, three-dimensional motion is the normal situation in astronomy; thus,

Eckroth, Charles A.

368

A Basic Astronomy Library.  

ERIC Educational Resources Information Center

This bibliography lists the most useful and scientifically accurate astronomy books published in the 1980s for beginners and students. The books are categorized under the topics of: (1) astronomy in general; (2) solar system as a whole; (3) planets; (4) asteroids, comets, and meteorites; (5) the sun; (6) stars and their evolution; (7) mikly way

Fraknoi, Andrew

369

To See the Unseen: A History of Planetary Radar Astronomy  

NASA Technical Reports Server (NTRS)

This book relates the history of planetary radar astronomy from its origins in radar to the present day and secondarily to bring to light that history as a case of 'Big Equipment but not Big Science'. Chapter One sketches the emergence of radar astronomy as an ongoing scientific activity at Jodrell Bank, where radar research revealed that meteors were part of the solar system. The chief Big Science driving early radar astronomy experiments was ionospheric research. Chapter Two links the Cold War and the Space Race to the first radar experiments attempted on planetary targets, while recounting the initial achievements of planetary radar, namely, the refinement of the astronomical unit and the rotational rate and direction of Venus. Chapter Three discusses early attempts to organize radar astronomy and the efforts at MIT's Lincoln Laboratory, in conjunction with Harvard radio astronomers, to acquire antenna time unfettered by military priorities. Here, the chief Big Science influencing the development of planetary radar astronomy was radio astronomy. Chapter Four spotlights the evolution of planetary radar astronomy at the Jet Propulsion Laboratory, a NASA facility, at Cornell University's Arecibo Observatory, and at Jodrell Bank. A congeries of funding from the military, the National Science Foundation, and finally NASA marked that evolution, which culminated in planetary radar astronomy finding a single Big Science patron, NASA. Chapter Five analyzes planetary radar astronomy as a science using the theoretical framework provided by philosopher of science Thomas Kuhn. Chapter Six explores the shift in planetary radar astronomy beginning in the 1970s that resulted from its financial and institutional relationship with NASA Big Science. Chapter Seven addresses the Magellan mission and its relation to the evolution of planetary radar astronomy from a ground-based to a space-based activity. Chapters Eight and Nine discuss the research carried out at ground-based facilities by this transformed planetary radar astronomy, as well as the upgrading of the Arecibo and Goldstone radars. A technical essay appended to this book provides an overview of planetary radar techniques, especially range-Doppler mapping.

Butrica, Andrew J.

1996-01-01

370

Naming asteroids for the popularisation of astronomy  

NASA Astrophysics Data System (ADS)

We give a detailed description of how the naming of asteroids was used as a prize in competitions run by educational institutions and museums. There were two events, one in Venezuela and one in Brazil, which used this as an attractive alternative method for the popularisation of astronomy. The first competition, named Bautizo Espacial (Space Baptism), consisted of scientific stories written by high school students. The second, called Grande Desafio (Big Challenge), was a competition where teams of students were challenged to design and build prototype equipment to fight forest fires. Nationally, both events received wide publicity through newspapers, radio, TV and web pages, reaching many people in both countries. As part of both the events, several activities promoting the public knowledge of astronomy were held. The asteroids that were named in these competitions are just some of the many discovered in a search programme developed by the Group of Theoretical Astrophysics of University of Los Andes in Mrida, Venezuela (Grupo de Astrofisica Terica de la Universidad de Los Andes) as a mainstream research programme. Finally, Asteroids for the Popularisation of Astronomy has been formally proposed to the IAU as a worldwide programme during the celebration of the International Year of Astronomy in 2009 (IYA2009).

Naranjo, O. A.

2008-06-01

371

Kriti 2010 Astronomy Design Problems Equinox, The Astronomy Club  

E-print Network

Kriti 2010 Astronomy Design Problems Equinox, The Astronomy Club February 8, 2010 Introduction The Astronomy Design Problems constitute a new event introduced in Kriti this year. Below, you will nd two-trivial. While both certainly have solu- tions, to someone new to amateur astronomy, they would represent

Plotkin, Joshua B.

372

STATISTICAL ANALYSIS OF 5 YEAR CONTINUOUS RADIO FLARE DATA FROM PERSEI, V711 TAURI, LIBRAE, AND UX ARIETIS  

E-print Network

@rsd.nrl.navy.mil Frank D. Ghigo National Radio Astronomy Observatory, P.O. Box 2, Green Bank, WV 24944; fghigoSTATISTICAL ANALYSIS OF 5 YEAR CONTINUOUS RADIO FLARE DATA FROM #12; PERSEI, V711 TAURI, LIBRAE, AND UX ARIETIS Mercedes T. Richards1 Department of Astronomy and Astrophysics, Pennsylvania State

Richards, Donald St. P.

373

History of Oriental Astronomy  

NASA Astrophysics Data System (ADS)

This volume deals specifically with recent original research in the history of Chinese, Korean, Japanese, Islamic, and Indian astronomy. It strikes a balance between landmarks of history of Ancient and Medieval Astronomy in the Orient on one hand, and on the other the transmission of the European Astronomy into the countries of the Orient. Most contributions are based on research by the experts in this field. The book also indicates the status of astronomy research in non-European cultural areas of the world. The book is especially of interest to historians of astronomy and science, and students of cultural heritage. Link: http://www.wkap.nl/prod/b/1-4020-0657-8

Ansari, S. M. Razaullah

2002-12-01

374

Developing Astronomy in Cuba  

NASA Astrophysics Data System (ADS)

Introduction Beginning from a brief historical introduction the up to day situation is presented and the topics relevant to Astronomy development analyzed from the view point of a person actually working in Astrophysics. Arising from national needs, Astronomical Calculations is the only "native-born" branch of astronomy in Cuba. Cuba was an observational platform capable to provide the Soviet Union with the 24 hours solar patrol needed by its Space Agency System to protect the men in orbit. This was the beginning of a very fruitful development of solar research in Cuba. Russia installed the instruments, trained the people to operate them, and gives the academic environment to develop the scientific work in solar physics, space weather, and related topics. What about Stellar Astronomy? The Cuban astro-climate is not good to develop an observational base. We are trying to develop stellar astronomy in collaboration with institutions capable to provide both, the academic and technical environment; but to continue developing Stellar Astronomy we need to influence the public opinion and convince people they need groups working in Astronomy. How to do that? Publishing. Giving conferences talking about OUR work, not only like spectators of the science. Showing science is culture in modern times. Showing projects in Astronomy can be cheap. This is very important! Astronomy is not a luxury. Real possibilities I consider the Virtual Observatory concept the more appropriate in the near future, but it is necessary to have a connectivity level that is not commonly provided in Cuba, and to train the people. Concluding remarks From my experience "engagement" is the key word for Astronomy development in developing countries. Astronomy can not be developed without an appropriate academic environment, and we have not it. It is not "only" about financial resources, it is about "real collaboration" with a mature partner and common research goals.

Rodriguez Taboada, R. E.

2006-08-01

375

Yale University Department of Astronomy  

E-print Network

Yale University Department of Astronomy Astronomy 110: Planets and Stars Course will be using selections from the following workbook: Lecture- Tutorials for Introductory Astronomy.93. It is available at the following website: http:// www.mypearsonstore.com/bookstore/lecture-tutorials-for-introductory-astronomy

376

Overview of lunar-based astronomy  

NASA Technical Reports Server (NTRS)

The opportunities along with the advantages and disadvantages of the Moon for astronomical observatories are carefully and methodically considered. Taking a relatively unbiased approach, it was concluded that lunar observatories will clearly be a major factor in the future of astronomy in the next century. He concludes that ground based work will continue because of its accessibility and that Earth orbital work will remain useful, primarily for convenience of access in constructing and operating very large space systems. Deep space studies will feature not only probes but extensive systems for extremely long baseline studies at wavelengths from gamma rays through visible and IR out to radio is also a conclusion drawn, along with the consideration that lunar astronomy will have found important permanent applications along lines such as are discussed at the present symposium and others quite unsuspected today.

Smith, Harlan J.

1988-01-01

377

Gravitational Waves and Time Domain Astronomy  

NASA Technical Reports Server (NTRS)

The gravitational wave window onto the universe will open in roughly five years, when Advanced LIGO and Virgo achieve the first detections of high frequency gravitational waves, most likely coming from compact binary mergers. Electromagnetic follow-up of these triggers, using radio, optical, and high energy telescopes, promises exciting opportunities in multi-messenger time domain astronomy. In the decade, space-based observations of low frequency gravitational waves from massive black hole mergers, and their electromagnetic counterparts, will open up further vistas for discovery. This two-part workshop featured brief presentations and stimulating discussions on the challenges and opportunities presented by gravitational wave astronomy. Highlights from the workshop, with the emphasis on strategies for electromagnetic follow-up, are presented in this report.

Centrella, Joan; Nissanke, Samaya; Williams, Roy

2012-01-01

378

arXiv:0910.1517v2[astro-ph.IM]10Jun2010 Experimental Astronomy manuscript No.  

E-print Network

multiple single dishes. The first multi-element radio interferometer for astronomy was built by Sir Martin Ryle [12]. An interferometer measures the cross-correlation between the signals for a given pair

Udgaonkar, Jayant B.

379

Mon. Not. R. Astron. Soc. 362, 924 (2005) doi:10.1111/j.1365-2966.2005.09283.x A sample of radio-loud active galactic nuclei in the Sloan  

E-print Network

surveys: the National Radio Astronomy Observatories (NRAO) Very Large Array (VLA) Sky Survey (NVSS INTRODUCTION In recent years, new radio surveys such as the National Radio As- tronomy Observatory (NRAO) Very. Ivezi´c4 1Institute for Astronomy, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ 2Max

Bechtold, Jill

380

Big Computing in Astronomy: Perspectives and Challenges  

NASA Astrophysics Data System (ADS)

Hardware progress in recent years has led to astronomical instruments gathering large volumes of data. In radio astronomy for instance, the current generation of antenna arrays produces data at Tbits per second, and forthcoming instruments will expand these rates much further. As instruments are increasingly becoming software-based, astronomers will get more exposed to computer science. This talk therefore outlines key challenges that arise at the intersection of computer science and astronomy and presents perspectives on how both communities can collaborate to overcome these challenges.Major problems are emerging due to increases in data rates that are much larger than in storage and transmission capacity, as well as humans being cognitively overwhelmed when attempting to opportunistically scan through Big Data. As a consequence, the generation of scientific insight will become more dependent on automation and algorithmic instrument control. Intelligent data reduction will have to be considered across the entire acquisition pipeline. In this context, the presentation will outline the enabling role of machine learning and parallel computing.BioVictor Pankratius is a computer scientist who joined MIT Haystack Observatory following his passion for astronomy. He is currently leading efforts to advance astronomy through cutting-edge computer science and parallel computing. Victor is also involved in projects such as ALMA Phasing to enhance the ALMA Observatory with Very-Long Baseline Interferometry capabilities, the Event Horizon Telescope, as well as in the Radio Array of Portable Interferometric Detectors (RAPID) to create an analysis environment using parallel computing in the cloud. He has an extensive track record of research in parallel multicore systems and software engineering, with contributions to auto-tuning, debugging, and empirical experiments studying programmers. Victor has worked with major industry partners such as Intel, Sun Labs, and Oracle. He holds a distinguished doctorate and a Habilitation degree in Computer Science from the University of Karlsruhe. Contact him at pankrat@mit.edu, victorpankratius.com, or Twitter @vpankratius.

Pankratius, Victor

2014-06-01

381

The Long Wavelength Array and the Radio Transient Sky  

Microsoft Academic Search

Transient radio sources are necessarily compact and usually are the locations of explosive or dynamic events, therefore offering unique opportunities for probing fundamental physics and astrophysics. In addition, short-duration transients are powerful probes of intervening media owing to dispersion, scattering, and Faraday rotation that modify the signals. While radio astronomy has an impressive record obtaining high time resolution, usually it

P. S. Ray; T. J. Lazio; S. Ellingson; S. Close; S. D. Hyman; B. A. Jacoby; W. Junor; N. E. Kassim; S. R. Kulkarni; Y. Pihlstrm; G. B. Taylor; D. Werthimer; P. Crane

2006-01-01

382

The Long Wavelength Array and the Radio Transient Sky  

Microsoft Academic Search

Transient radio sources are necessarily compact and usually are the locations of explosive or dynamic events, therefore offering unique opportunities for probing fundamental physics and astrophysics. In addition, short-duration transients are powerful probes of intervening media owing to dispersion, scattering, and Faraday rotation that modify the signals. While radio astronomy has an impressive record obtaining high time resolution, usually it

P. S. Ray; T. J. W. Lazio; S. Ellingson; S. Close; P. Crane; S. D. Hyman; B. A. Jacoby; W. Junor; N. E. Kassim; S. R. Kulkarni; Y. M. Pihlstrom; G. B. Taylor; D. Werthimer

2005-01-01

383

Teaching Astronomy with Technology  

NASA Astrophysics Data System (ADS)

Students today are expected to have access to computers and the Internet. Students young and old, in school and out of school, are interested in learning about astronomy, and have computers to use for this. Teach Astronomy is a website with a comprehensive digital astronomy textbook freely available to students and educators. In addition to the textbook, there are astronomy Wikipedia articles, image archives from Astronomy Picture of the Day and AstroPix, and video lectures covering all topics of astronomy. Teach Astronomy has a unique search tool called the wikimap that can be used to search through all of the resources on the site. Astronomy: State of the Art (ASOTA) is a massive, open, online course (MOOC). Over 18,000 students have enrolled over the past year and half. This MOOC has been presented in various forms. First, only to students on the web, with content released weekly on host site Udemy. Then to university students who met formally in the classroom for educational activities, but were also expected to watch lectures online on their own time. Presently, it is available online for students to go at their own pace. In the future it will be available in an extended format on a new host site, Coursera. ASOTA instructors use social media to interact with students. Students ask questions via the course host site, Udemy. Live question and answer sessions are conducted using Google Hangouts on Air, and interesting and relevant astronomy news, or supplementary educational content is shared via the ASOTA Facebook page. Teaching on the Internet may seem impersonal and impractical, but by learning to use all of these tools, instructors have the ability to interact with students, and keep them engaged.

Austin, Carmen; Impey, Chris David; Wenger, Matthew

2015-01-01

384

Astronomy Landscape in Africa  

NASA Astrophysics Data System (ADS)

The vision for astronomy in Africa is embedded in the African Space Policy of the African Union in early 2014. The vision is about positioning Africa as an emerging hub for astronomy sciences and facilities. Africa recognized the need to take advantage of its natural resource, the geographical advantage of the clear southern skies and pristine sites for astronomy. The Pan African University (PAU) initiative also presents an opportunity as a post-graduate training and research network of university nodes in five regions of Africa and supported by the African Union. The Southern African node based in South Africa concentrates on space sciences which also includes astronomy. The PAU aims to provide the opportunity for advanced graduate training and postgraduate research to high-performing African students. Objectives also include promoting mobility of students and teachers and harmonizing programs and degrees.A number of astronomy initiatives have burgeoned in the Southern African region and these include the Southern Africa Largest Optical Telescope (SALT), HESS (High Energy Stereoscopic System), the SKA (Square Kilometre Array) and the AVN (African Very Long Baseline Interferometer Network). There is a growing appetite for astronomy sciences in Africa. In East Africa, the astronomy community is well organized and is growing the East African Astronomical society (EAAS) held its successful fourth annual conference since 2010 on 30 June to 04 July 2014 at the University of Rwanda. Centred around the Role of Astronomy in Socio-Economic Transformation, this conference aimed at strengthening capacity building in Astronomy, Astrophysics and Space Science in general, while providing a forum for astronomers from the region to train young and upcoming scientists.

Nemaungani, Takalani

2015-01-01

385

VizieR Online Data Catalog: Properties of 18286 SDSS radio galaxies (Best+, 2012)  

NASA Astrophysics Data System (ADS)

A sample of 18286 radio-loud active galactic nuclei (AGN) is presented, constructed by combining the seventh data release of the Sloan Digital Sky Survey with the NRAO (National Radio Astronomy Observatory) VLA (Very Large Array) Sky Survey (NVSS) and the Faint Images of the Radio Sky at Twenty centimetres (FIRST) survey. Using this sample, the differences between radio galaxies of "high-excitation" ("quasar-mode"; hereafter HERG) and "low-excitation" ("radio-mode"; LERG) are investigated. (1 data file).

Best, P. N.; Heckman, T. M.

2012-11-01

386

Astronomy in Ukraine  

E-print Network

The current and prospective status of astronomical research in Ukraine is discussed. A brief history of astronomical research in Ukraine is presented and the system organizing scientific activity is described, including astronomy education, institutions and staff, awarding higher degrees/titles, government involvement, budgetary investments and international cooperation. Individuals contributing significantly to the field of astronomy and their accomplishments are mentioned. Major astronomical facilities, their capabilities, and their instrumentation are described. In terms of the number of institutions and personnel engaged in astronomy, and of past accomplishments, Ukraine ranks among major nations of Europe. Current difficulties associated with political, economic and technological changes are addressed and goals for future research activities presented.

Ya. V. Pavlenko; I. B. Vavilova; T. Kostiuk

2005-12-16

387

The Unified Astronomy Thesaurus  

NASA Astrophysics Data System (ADS)

The Unified Astronomy Thesaurus (UAT) is an open, interoperable and community-supported thesaurus which unifies the existing divergent and isolated Astronomy & Astrophysics vocabularies into a single high-quality, freely-available open thesaurus formalizing astronomical concepts and their inter-relationships. The UAT builds upon the existing IAU Thesaurus with major contributions from the astronomy portions of the thesauri developed by the Institute of Physics Publishing, the American Institute of Physics, and SPIE. We describe the effort behind the creation of the UAT and the process through which we plan to maintain the document updated through broad community participation.

Accomazzi, A.; Gray, N.; Erdmann, C.; Biemesderfer, C.; Frey, K.; Soles, J.

2014-05-01

388

Mathematical Astronomy in India  

NASA Astrophysics Data System (ADS)

Astronomy in South Asia's Sanskrit tradition, apparently originating in simple calendric computations regulating the timing of ancient ritual practices, expanded over the course of two or three millennia to include detailed spherical models, an endless variety of astrological systems, and academic mathematics in general. Assimilating various technical models, methods, and genres from the astronomy of neighboring cultures, Indian astronomers created new forms that were in turn borrowed by their foreign counterparts. Always recognizably related to the main themes of Eurasian geocentric mathematical astronomy, Indian astral science nonetheless maintained its culturally distinct character until Keplerian heliocentrism and Newtonian mechanics replaced it in colonial South Asia's academic mainstream.

Plofker, Kim

389

Bakersfield College: Astronomy Notes  

NSDL National Science Digital Library

Nick Strobel, from Bakersfield College, created this website to provide educational materials for the introductory astronomy course he teaches. Users can find a seventeen chapter online textbook, equipped with fantastic astronomy images and numerous review questions. The site offers a description of angular momentum; a mathematics review; tables of astronomy constants, physical constants, planets, and stars; and a glossary. Students can benefit by reading the study guide, which addresses ways to improve study habits and exam scores. Be sure to read Mr. Strobel's Copyright Notice prior to utilizing the resources avaiable here.

390

Robert Gendler's Astronomy Pictures  

NSDL National Science Digital Library

Robert Gendler is an amateur astronomer with an extensive online gallery of his astronomy images. His pictures are available in high resolution on the web and for purchase in print form through his website. The author also provides links to additional resources which include: astronomical objects, an astronomy primer for beginners, an image gallery and external links. This is a nice resource for those interested in visual aspects of astronomy. Most of the resources are available free of charge, but the author does provide high resolution prints for sale.

Gendler, Robert

2009-05-18

391

Using multiple beams to identify radio frequency interference in the search for extraterrestrial intelligence  

Microsoft Academic Search

The Allen Telescope Array (ATA) is a multiuser instrument and will perform simultaneous radio astronomy and radio search for extraterrestrial intelligence (SETI) observations. It is a multibeam instrument, with 16 independently steerable dual-polarization beams at four different tunings. Here we describe a new method for identifying radio frequency interference (RFI) that leverages the unique attributes of the ATA. Given four

G. R. Harp

2005-01-01

392

Compact Radio Cores in the Galactic Center and Elsewhere 1 Heino Falcke  

E-print Network

observational programs have tackled compact radio nuclei in nearby galaxies and low­power AGN, there have beenCompact Radio Cores in the Galactic Center and Elsewhere 1 Heino Falcke Department of Astronomy, University of Maryland, College Park, MD 20742­2421, USA (hfalcke@astro.umd.edu) Abstract. Compact radio

Falcke, Heino

393

GAIN ESTIMATION METHODS FOR POLARIZED RADIO TELESCOPE ARRAYS A.J. Boonstra  

E-print Network

GAIN ESTIMATION METHODS FOR POLARIZED RADIO TELESCOPE ARRAYS A.J. Boonstra 1¡ and A.J. van der@cas.et.tudelft.nl In radio telescope arrays, the complex receiver gains and sensor noise powers are initially unknown phase. 1. INTRODUCTION In interferometric radio astronomy, the telescope array complex receiver gains

van der Veen, Alle-Jan

394

Signal Processing Tools for Radio Alle-Jan van der Veen and Stefan J. Wijnholds  

E-print Network

Radio astronomy is known for its very large telescope dishes, but is currently making a transition, the aperture of a radio telescope has to be 5 to 6 orders of magni- tude larger than that of an optical telescope to provide the same resolution. This implies that the aperture of a radio telescope should have

Langendoen, Koen

395

Astronomy, Astrology, and Medicine  

NASA Astrophysics Data System (ADS)

Astronomy and astrology were combined with medicine for thousands of years. Beginning in Mesopotamia in the second millennium BCE and continuing into the eighteenth century, medical practitioners used astronomy/astrology as an important part of diagnosis and prescription. Throughout this time frame, scientists cited the similarities between medicine and astrology, in addition to combining the two in practice. Hippocrates and Galen based medical theories on the relationship between heavenly bodies and human bodies. In an enduring cultural phenomenon, parts of the body as well as diseases were linked to zodiac signs and planets. In Renaissance universities, astronomy and astrology were studied by students of medicine. History records a long tradition of astrologer-physicians. This chapter covers the topic of astronomy, astrology, and medicine from the Old Babylonian period to the Enlightenment.

Greenbaum, Dorian Gieseler

396

Physics & Astronomy Degree options  

E-print Network

148 Physics & Astronomy Degree options BSc (Single Honours Degrees) Astrophysics Physics MPhys (Single Honours Degrees) Astrophysics Physics Theoretical Physics BSc (Joint Honours Degrees) Physics) Theoretical Physics and Mathematics MSci (Joint Honours Degree) Physics and Chemistry Entrance Requirements

Brierley, Andrew

397

Cultural Astronomy in Japan  

NASA Astrophysics Data System (ADS)

While Japan is known more for its contributions to modern astronomy than its archaeoastronomical sites, there is still much about the culture's heritage that is of interest in the study of cultural astronomy. This case study provides an overview of historical considerations necessary to understand the place of astronomy in Japanese society as well as methodological considerations that highlight traditional approaches that have at times been a barrier to interdisciplinary research. Some specific areas of study in the cultural astronomy of Japan are discussed including examples of contemporary research based on interdisciplinary approaches. Japan provides a fascinating background for scholars who are willing to go beyond their curiosity for sites of alignment and approach the culture with a desire to place astronomical iconography in social context.

Renshaw, Steven L.

398

People in Astronomy  

NSDL National Science Digital Library

This biographical index provides short descriptions of the lives and achievements of prominent astronomers, physicists, mathematicians, and other persons who have made contributions to astronomy. Links to related persons and topics are embedded in the text.

399

Center for Astronomy Education  

NSDL National Science Digital Library

The focus of the Jet Propulsion Laboratory's Center for Astronomy Education is simple, yet important: it is "dedicated to the professional development of introductory astronomy instructors." To that end, this website provides articles from guest bloggers, educational materials, and an array of high-quality resources. On the homepage, visitors can view sections that include Teaching Strategies, Publications, and Seeing the Universe. The Teaching Strategies area includes guest posts from college level astronomy instructors, while the archive includes posts focused on classroom assessment, curriculum, and goals. Moving on, the Seeing the Universe area includes an archive of images that can be used in the astronomy classroom. One of the best overall resources in the Teaching Strategies section is "You Don't Have to Do it from Scratch," which teaches instructors how to use conventional PowerPoint lectures more effectively. Finally, visitors can connect with the Center via Facebook and other social media sites.

2012-09-14

400

UCSB Infosurf: Astronomy  

NSDL National Science Digital Library

As part of the University of California Santa Barbara Library, the Astronomy subject webpage contains dozens of links on the subject. Sites are categorized in indexes and gateways, NASA pages, observatories, organizations and associations, current topics, interactive resources, and periodicals.

Anderson, Duane

2003-10-10

401

Applications of correlator chips in radio science  

NASA Technical Reports Server (NTRS)

Spectral line observations in radio astronomy require simultaneous power estimation in many (often hundreds to thousands) frequency bins. Digital autocorrelation spectrometers, which appeared thirty years ago, are now being implemented in VLSI. The same architecture can be used to implement transversal digital filters. This was done at the Arecibo Observatory for pulse compression in radar observations of Venus.

Hagen, John B.

1992-01-01

402

NASA thesaurus: Astronomy vocabulary  

NASA Technical Reports Server (NTRS)

A terminology of descriptors used by the NASA Scientific and Technical information effort to index documents in the area of astronomy is presented. The terms are listed in hierarchical format derived from the 1988 edition of the NASA Thesaurus Volume 1 -- Hierarchical Listing. Over 1600 terms are included. In addition to astronomy, space sciences covered include astrophysics, cosmology, lunar flight and exploration, meteors and meteorites, celestial mechanics, planetary flight and exploration, and planetary science.

1988-01-01

403

Astronomy in the Marketplace  

NSDL National Science Digital Library

This is an activity about cultural references to astronomy. Learners will create a list of products that have been named after astronomical objects, which the class discusses. As a homework project, they can search local stores or media for additional astronomical references. This is Activity M-3 of Universe at Your Fingertips 2.0: A Collection of Activities and Resources for Teaching Astronomy DVD-ROM, which is available for purchase.

2013-04-30

404

Music and Astronomy  

E-print Network

What do Brian May (the Queen's lead guitarist), William Herschel and the Jupiter Symphony have in common? And a white dwarf, a piano and Lagartija Nick? At first glance, there is no connection between them, nor between Music and Astronomy. However, there are many revealing examples of musical Astronomy and astronomical Music. This four-page proceeding describes the sonorous poster that we showed during the VIII Scientific Meeting of the Spanish Astronomical Society.

J. A. Caballero; S. Gonzalez Sanchez; I. Caballero

2008-10-16

405

Achievements and Mirages in Uhecr and Neutrino Astronomy  

E-print Network

Photon Astronomy ruled the last four centuries while wider photon band ruled last radio-X-Gamma century of discovery. Present decade may see the rise and competition of UHECR and UHE Neutrino Astronomy. Tau Neutrino may win and be the first flavor revealed. It could soon rise at horizons in AUGER at EeV energies, if nucleons are the main UHECR currier. If on the contrary UHECR are Lightest nuclei (He, Li. B) UHE tau neutrino maybe suppressed at EeV and enhanced at tens -hundred PeV. Detectable in AMIGA and HEAT denser sub-array in AUGER. Within a few years.

Fargion, D

2009-01-01

406

Bad Astronomy Goes Hollywood  

NASA Astrophysics Data System (ADS)

It can be argued that astronomy is the oldest of all the sciences, so you'd think that after all this time people would have a pretty good understanding of it. In reality, however, misconceptions about astronomy abound, and even basic concepts are misunderstood. There are many sources of these cosmic misconceptions, including incorrect textbooks, parents and/or teachers who don't understand astronomy and therefore spread misinformation, urban legends, and so on. Perhaps the most pervasive source of bad astronomy is Hollywood. Science fiction movies are enormously popular, but are commonly written and directed by people who don't have even a passing familiarity with astronomy. The smash hit "Armageddon" (the number one box office movie of 1998), for example, used vast quantities of incorrect astronomy in the plot. It reinforced such popular misconceptions as huge asteroids impacting the Earth with little warning, small meteorites being hot when they impact, air existing in space, and that a simple bomb can blow up an asteroid the size of a small moon (even when the bomb is buried only 800 feet deep!). However, movie scenes can be used as a hook that engages the student, helping them learn and remember the correct science. In this talk, I will light-heartedly discuss specific examples of common misinformation, using movie clips, diagrams, and a splash of common sense to show just where Hollywood gets it wrong, and what you can do to help students and the public get it right.

Plait, P.

2003-05-01

407

arXiv:1108.4037v1[astro-ph.CO]19Aug2011 Ultra Steep Spectrum radio sources in the Lockman Hole: SERVS  

E-print Network

Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA, UK 13 National Radio´isica da Universidade de Lisboa, Lisbon, Portugal 3 UK Astronomy Technology Centre, Royal Observatory Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA 14 Institute of Cosmology

Norris, Ray

408

Plasma and radio waves from Neptune: Source mechamisms and propagation  

NASA Technical Reports Server (NTRS)

The purpose of this project was to conduct a comprehensive investigation of the radio wave emission observed by the planetary radio astronomy (PRA) instrument on board Voyager 2 as it flew by Neptune. The study has included data analysis, theoretical and numerical calculations, and ray tracing to determine the possible source mechanisms and locations of the radiation, including the narrowband bursty and smooth components of the Neptune radio emission.

Menietti, J. Douglas

1994-01-01

409

A Collaborative Astronomy Project Between Multimedia and Physics Undergraduate Majors  

NASA Astrophysics Data System (ADS)

During the summer of 2004, faculty and undergraduate multimedia and physics interns from the University of North Carolina at Asheville and nearby Furman University joined together at the Pisgah Astronomical Research Institute to develop a new education and public outreach program of radio astronomy by utilizing the StarLab portable planetarium system. The program consists of three components: the StarLab cylinder for projection of the radio sky; display of a pulsar on the radio sky; and teaching and learning materials accessible through the Internet and CD-ROM. The multimedia and physics interns worked together to articulate and communicate aspects of their disciplines as they related to the development of the cylinder, the depiction of the pulsars and pulsar projector, and classroom activities for teachers and students. As a result, the cylinder shows both the radio sky and illustrates five distinct types of radio sources. The cylinder is augmented further through the use of an audio-visual pulsar projector, which emits pulses with sound for the audio-visually challenged. The activities present teachers with lesson plans related to radio astronomy topics. We discuss the unique development by this team needed to accomplish the program's first year goals. We acknowledge support from the NSF Internship in Public Science Education Program grant number 0324729.

Castelaz, M. W.; Walsh, L.; LaFratta, M.; Moffett, D. A.

2004-12-01

410

Astronomical Book Trek: Astronomy Books of 1983.  

ERIC Educational Resources Information Center

Presents an annotated list of technical and non-technical astronomy books. Topic areas of non-technical books include general astronomy, amateur astronomy, computers and astronomy, history of astronomy, pseudoscience, space exploration, physics and astronomy, and textbooks. Each entry includes author, title, description, source, and current cost.

Fraknoi, Andrew

1984-01-01

411

Radio-wave propagation in space  

NASA Astrophysics Data System (ADS)

The characteristics of radio waves propagating in space are discussed, with attention given to their astronomical applications. Physical phenomena influencing the propagation of radio waves in the earth's atmospheres are considered, including atmospheric absorption, attenuation and refraction effects. The uses of radar interferometry in interstellar and interplanetary astronomy are described and radar data are presented concerning coronal scattering; interplanetary scintillations; relativistic time delay measurements; and gravitational lens effects. The effect of the gravitational field of interstellar space on the propagation of radio waves is also discussed.

Iakovlev, O. I.

412

Mon. Not. R. Astron. Soc. 392, 617629 (2009) doi:10.1111/j.1365-2966.2008.14068.x Evolution of the radio-loud galaxy population  

E-print Network

constructed from the cross-correlation of the National Radio Astronomy Observatory Very Large Array Sky Survey for Astronomy, Royal Observatory Edinburgh, Blackford Hill, Edinburgh EH9 3HJ Accepted 2008 October 8. Received of the radio-loud galaxy population E. Donoso,1 P. N. Best2 and G. Kauffmann1 1Max-Planck-Institut f

Best, Philip

413

The history of radio telescopes, 1945-1990  

NASA Astrophysics Data System (ADS)

Forged by the development of radar during World War II, radio astronomy revolutionized astronomy during the decade after the war. A new universe was revealed, centered not on stars and planets, but on the gas between the stars, on explosive sources of unprecedented luminosity, and on hundreds of mysterious discrete sources with no optical identifications. Using radio telescopes that looked nothing like traditional (optical) telescopes, radio astronomers were a very different breed from traditional (optical) astronomers. This pathbreaking of radio astronomy also made it much easier for later astronomies and their telescopes (X-ray, ultraviolet, infrared, gamma-ray) to become integrated into astronomy after the launch of the space age in the 1960s. This paper traces the history of radio telescopes from 1945 through about 1990, from the era of converted small-sized, military radar antennas to that of large interferometric arrays connected by complex electronics and computers; from the era of strip-chart recordings measured by rulers to powerful computers and display graphics; from the era of individuals and small groups building their own equipment to that of Big Science, large collaborations and national observatories.

Sullivan, Woodruff T.

2009-08-01

414

FAKULTT FR PHYSIK UND ASTRONOMIE DEPARTMENT OF PHYSICS AND ASTRONOMY  

E-print Network

FAKULT?T F?R PHYSIK UND ASTRONOMIE DEPARTMENT OF PHYSICS AND ASTRONOMY DEKANAT / OFFICE OF THE DEAN beizufügen: 1. Die Angaben des Faches, für das die Habilitation erfolgen soll (Physik oder Astronomie). 1x 2

Heermann, Dieter W.

415

CCD Astronomy Software User's Guide  

E-print Network

CCDSoft CCD Astronomy Software User's Guide Version 5 Revision 1.11 Copyright © 1992­2006 SantaSky Astronomy Software, and AutomaDome are trademarks of Software Bisque. WindowsTM is a trademark of Microsoft

416

Cool Cosmos: Infrared Astronomy Tutorial  

NSDL National Science Digital Library

This Web site includes the following sections: Discovery of Infrared; What is Infrared?; Infrared Astronomy; Atmospheric Windows; Near, Mid & Far Infrared; IR Astronomy Timeline; Background & Technology; The Infrared Universe; Infrared Spectroscopy; News & Discoveries; and Images & Videos.

NASA IPAC/CALTECH

417

Radio quite site qualification for the Brasilian Southern Space Observatory by monitoring the low frequency 10-240 MHz Eletromagnetic Spectrum  

Microsoft Academic Search

The monitoring of the level of the radio interference in the Site of the Brazilian Southern Space Observatory - SSO\\/CRS\\/CIE\\/INPE - MCT, (29S, 53W), So Martinho da Serra, RS, in south a of Brazil, aims to gather spectral data for the Observatory's Site qualification as a radio quite site for installation of Radio Astronomy instrumentation, free of radio noise. The

Guilherme Simon da Rosa; Nelson Jorge Schuch; Cassio Espindola Antunes; Natanael Gomes

2008-01-01

418

The ATA Digital Processing Requirements are Driven by RFI Concerns As a new generation radio telescope, the Allen Telescope Array (ATA) is a prototype for  

E-print Network

generation radio telescope, the Allen Telescope Array (ATA) is a prototype for the SKA. Here we describe, radio telescopes must support a wide range of RFI mitigation strategies including online deterministic processing. As radio frequency interference (RFI) becomes increasingly problematical for radio astronomy

Ellingson, Steven W.

419

Rescuing Middle School Astronomy  

NASA Astrophysics Data System (ADS)

There is a crisis in education at the middle school level (Spellings, 2006). Recent studies point to large disparities in middle school performance in schools with high minority populations. The largest disparities exist in areas of math and science. Astronomy has a universal appeal for K-12 students but is rarely taught at the middle school level. When it is taught at all it is usually taught in isolation with few references in other classes such as other sciences (e.g. physics, biology, and chemistry), math, history, geography, music, art, or English. The problem is greatest in our most challenged school districts. With scores in reading and math below national averages in these schools and with most state achievement tests ignoring subjects like astronomy, there is little room in the school day to teach about the world outside our atmosphere. Add to this the exceedingly minimal training and education in astronomy that most middle school teachers have and it is a rare school that includes any astronomy teaching at all. In this presentation, we show how to develop and offer an astronomy education training program for middle school teachers encompassing a wide range of educational disciplines that are frequently taught at the middle school level. The prototype for this program was developed and launched in two of the most challenged and diverse school systems in the country; D.C. Public Schools, and Montgomery County (MD) Public Schools.

Mayo, L. A.; Janney, D.

2010-12-01

420

Massive Datasets in Astronomy  

E-print Network

Astronomy has a long history of acquiring, systematizing, and interpreting large quantities of data. Starting from the earliest sky atlases through the first major photographic sky surveys of the 20th century, this tradition is continuing today, and at an ever increasing rate. Like many other fields, astronomy has become a very data-rich science, driven by the advances in telescope, detector, and computer technology. Numerous large digital sky surveys and archives already exist, with information content measured in multiple Terabytes, and even larger, multi-Petabyte data sets are on the horizon. Systematic observations of the sky, over a range of wavelengths, are becoming the primary source of astronomical data. Numerical simulations are also producing comparable volumes of information. Data mining promises to both make the scientific utilization of these data sets more effective and more complete, and to open completely new avenues of astronomical research. Technological problems range from the issues of database design and federation, to data mining and advanced visualization, leading to a new toolkit for astronomical research. This is similar to challenges encountered in other data-intensive fields today. These advances are now being organized through a concept of the Virtual Observatories, federations of data archives and services representing a new information infrastructure for astronomy of the 21st century. In this article, we provide an overview of some of the major datasets in astronomy, discuss different techniques used for archiving data, and conclude with a discussion of the future of massive datasets in astronomy.

Robert J. Brunner; S. George Djorgovski; Thomas A. Prince; Alex S. Szalay

2001-06-26

421

Teaching Astronomy at SRTM University, Nanded  

NASA Astrophysics Data System (ADS)

School of Physical Sciences of SRTM University, Nanded, Maharashtra offers Astronomy & Astrophysics as one of the specializations at postgraduate (M. Sc) level. With a view to provide training in astronomical observations, data analysis and interpretation of the data; the school has incorporated a set of observational as well as data analysis exercises as a part of this course. The school at present is having observing facilities like, two 8 inch aperture Meade optical telescopes equipped with SSP-3 and SSP-3A photometers, 416-XT CCD camera and is in the process of procurement of Advanced Coma Free 16 inch (40cm) aperture Meade LX-200 optical telescope along with ST-10XME CCD camera and SBIG spectrograph. In addition to these facilities, with an objective of spreading the joy and excitement of radio astronomy among the postgraduate and research students, the school is procuring one 10-feet diameter dish antenna and 1420 MHz Hydrogen Line Spectrometer (radio observation setup). For the solar irradiance measurement, the school is also procuring one StellarNetUV-VIS-NIR Spectro-Radiometer. These facilities are quite suitable for continuous monitoring of a variety of variable stars, carrying out spectroscopic observations of a variety of objects, 21-cm observations of star-forming regions, solar irradiance measurement etc. This presentation is aimed to give a brief summary of various activities that are conducted at M Sc. level using the facilities available in our university department.

Patil, Madhav Khushalrao

422

DEPARTMENT OF PHYSICS AND ASTRONOMY  

E-print Network

DEPARTMENT OF PHYSICS AND ASTRONOMY DARTMOUTH COLLEGE GRADUATE STUDENT HANDBOOK 2014-15 #12;2 TABLE .....................................................................28 #12;3 SECTION I PRACTICAL MATTERS 1. WELCOME AND OVERVIEW The Department of Physics and Astronomy undergraduate courses. The course requirements for physics and astronomy students are given in Section II-1

423

DEPARTMENT OF PHYSICS AND ASTRONOMY  

E-print Network

DEPARTMENT OF PHYSICS AND ASTRONOMY DARTMOUTH COLLEGE GRADUATE STUDENT HANDBOOK 2012-13 #12;2 TABLE .....................................................................27 #12;3 SECTION I PRACTICAL MATTERS 1. WELCOME AND OVERVIEW The Department of Physics and Astronomy with some undergraduate courses. The course requirements for physics and astronomy students are given

424

Taught degrees MSc in Astronomy  

E-print Network

Essentials Taught degrees MSc in Astronomy MSc in Cosmology Research degrees MPhil, PhD in Astronomy Related degrees MSc in Computational Mathematics (p119) MSc in Particle Physics (p137) MSc-class undergraduate honours degree in a physics-, mathematics- or astronomy-based subject. Other degrees

Sussex, University of

425

Taught degrees MSc in Astronomy  

E-print Network

Essentials Taught degrees MSc in Astronomy MSc in Cosmology Research degrees MPhil, PhD in Astronomy Related degrees MSc in Particle Physics (p135) MSc in Physics (p135) MSc in Physics (Euro-class undergraduate honours degree in a physics-, mathematics- or astronomy-based subject. Other degrees

Sussex, University of

426

The Profile of Astronomy Amateurs  

Microsoft Academic Search

Presentation of questionnaires carried out on Polish Astronomy Portal websites. There was over 80 questionnaires during 2 years period. As most part of users visiting this website are astronomy amateurs, we can assume questionnaires give a picture of astronomy amateurs community. Questionnaires can be divided into four main thematical groups: profile of users (age, sex, activities), what do they think

K. Czart

2005-01-01

427

School-Based Extracurricular Astronomy  

ERIC Educational Resources Information Center

The International Year of Astronomy in 2009 focused considerable public attention on Astronomy and generated valuable resources for educators. These activities are an effective vehicle for promoting Science to students and to the wider school community. The most engaging practical astronomy activities are best delivered with sustained support from

Stanger, Jeffrey J.

2010-01-01

428

UNDERGRADUATE PROGRAMS DEPARTMENT OF ASTRONOMY  

E-print Network

richness of the universe. Join this adventure by exploring the astronomy program at the University of TexasUNDERGRADUATE PROGRAMS DEPARTMENT OF ASTRONOMY The UniversiTy of Texas aT aUsTin Astronomy is one of the greatest adventures in human history, a quest to understand our origin and fate within the infinite

Jefferys, William

429

Teaching Astronomy in UK Schools  

ERIC Educational Resources Information Center

This article attempts to summarise the good, bad and (occasionally) ugly aspects of teaching astronomy in UK schools. It covers the most common problems reported by teachers when asked about covering the astronomy/space topics in school. Particular focus is given to the GCSE Astronomy qualification offered by Edexcel (which is currently the

Roche, Paul; Roberts, Sarah; Newsam, Andy; Barclay, Charles

2012-01-01

430

Quickly Creating Interactive Astronomy Illustrations  

ERIC Educational Resources Information Center

An innate advantage for astronomy teachers is having numerous breathtaking images of the cosmos available to capture students' curiosity, imagination, and wonder. Internet-based astronomy image libraries are numerous and easy to navigate. The Astronomy Picture of the Day, the Hubble Space Telescope image archive, and the NASA Planetary

Slater, Timothy F.

2015-01-01

431

The Murchison Widefield Array: The Square Kilometre Array Precursor at Low Radio Frequencies  

E-print Network

The Murchison Widefield Array (MWA) is one of three Square Kilometre Array Precursor telescopes and is located at the Murchison Radio-astronomy Observatory in the Murchison Shire of the mid-west of Western Australia, a ...

Goeke, Robert F.

432

Astronomy Librarian - Quo Vadis?  

NASA Astrophysics Data System (ADS)

"You don't look like a librarian" is a phrase we often hear in the astronomy department or observatory library. Astronomy librarians are a breed apart, and are taking on new and non-traditional roles as information technology evolves. This talk will explore the future of librarians and librarianship through the lens of some of the recent talks given at the sixth "Libraries and Information Services in Astronomy" conference held in Pune, India in February 2010. We will explore the librarian's universe, illustrating how librarians use new technologies to perform such tasks as bibliometrics, how we are re-fashioning our library spaces in an increasingly digital world and how we are confronting the brave new world of Open Access, to name but a few topics.

Lagerstrom, Jill; Grothkopf, Uta

433

Astronomy.com  

NSDL National Science Digital Library

The publishers of Astronomy magazine (originally reviewed in the August 8, 1997 Scout Report http://scout.cs.wisc.edu/report/sr/1997/scout-970808.html#10 ) recently announced the release of their updated and expanded Website. The site has the look and feel of a commercial site (and a few ads), but all content is free. Designed for Astronomy hobbyists, the site contains the latest space news, feature articles, a nice beginners section, tips and tools for parents and teachers, a photo gallery, and star charts. Users can also participate in discussion forums, search for astronomy organizations, and subscribe to a free bulletin service. Please note that registration is required for access to some parts of the site.

434

Gamma-ray Astronomy  

E-print Network

The relevance of gamma-ray astronomy to the search for the origin of the galactic and, to a lesser extent, the ultra-high-energy cosmic rays has long been recognised. The current renaissance in the TeV gamma-ray field has resulted in a wealth of new data on galactic and extragalactic particle accelerators, and almost all the new results in this field were presented at the recent International Cosmic Ray Conference (ICRC). Here I summarise the 175 papers submitted on the topic of gamma-ray astronomy to the 30th ICRC in Merida, Mexico in July 2007.

Jim Hinton

2007-12-20

435

Open Astronomy Curricula  

NSDL National Science Digital Library

This set of twelve lesson plans is intended to encourage the teaching of astronomy to K-12 students. The lessons are designed to make use of a planetarium projector, but they can be modified for use with different planetarium systems, including the free (General Public License) planetarium software 'Stellarium'. They introduce students to basics of earth's movements, the Greco-Roman constellations, and objects in the sky (for younger students); the differences between stars and planets, planetary motions, phases of the moon; stellar navigation, the solstices and equinoxes, the history of astronomy, and other topics (secondary students). The lessons are available in PDF (for printing) and RTF (for editing) formats.

2010-11-24

436

Cosmic Ray Astronomy  

E-print Network

Cosmic ray astronomy attempts to identify and study the sources of ultrahigh energy cosmic rays. It is unique in its reliance on charged particles as the information carriers. While no discrete source of ultrahigh energy cosmic rays has been identified so far, a new generation of detectors is acquiring the huge exposure that is needed at the highest energies, where deflection by magnetic fields is minimized and the background from distant sources is eliminated by pion photoproduction. In this paper, we summarize the status of cosmic ray astronomy, describing the detectors and the analysis techniques.

Paul Sommers; Stefan Westerhoff

2008-02-09

437

Meta Research: Astronomy Research  

NSDL National Science Digital Library

Meta Research, headed by astronomer Tom Van Flandern, fosters "research into ideas not otherwise supported solely because they conflict with mainstream theories in Astronomy." The website offers papers on alternative explanations in the fields of cosmology, solar systems, and gravity. Individuals can find out about upcoming solar eclipse expeditions and view images from past trips. Students and educators can find links to numerous astronomy-related animations including the Face on Mars, Fission Model, and Leonids meteor storm. Interested visitors can learn about membership opportunities and Meta Research publications.

438

Babylonian Mathematical Astronomy  

NASA Astrophysics Data System (ADS)

The earliest known form of mathematical astronomy of the ancient world was developed in Babylonia in the 5th century BCE. It was used for predicting a wide range of phenomena of the Moon, the Sun, and the planets. After a brief discussion of the material evidence and historical context of Babylonian mathematical astronomy, its main concepts and methods are illustrated on the basis of a tablet with computed data for Jupiter. Finally, the past, present, and future directions of research are briefly addressed.

Ossendrijver, Mathieu

439

Astronomy before the telescope.  

NASA Astrophysics Data System (ADS)

This book is the most comprehensive and authoritative survey to date of world astronomy before the telescope in AD 1609. International experts have contributed chapters examining what observations were made, what instruments were used, the effect of developments in mathematics and measurement, and the diversity of early views of cosmology and astrology. The achievements of European astronomers from prehistoric times to the Renaissance are linked with those of ancient Egypt and Mesopotamia, India and the Islamic world. Other chapters deal with early astronomy in the Far East and in the Americas, and with traditional astronomical knowledge in Africa, Australia and the Pacific.

Walker, C.

440

Cognitive radio: Making software radios more personal  

Microsoft Academic Search

Software radios are emerging as platforms for multiband multimode personal communications systems. Radio etiquette is the set of RF bands, air interfaces, protocols, and spatial and temporal patterns that moderate the use of the radio spectrum. Cognitive radio extends the software radio with radio-domain model-based reasoning about such etiquettes. Cognitive radio enhances the flexibility of personal services through a Radio

Joseph Mitola; Gerald Quentin Maguire Jr.

1999-01-01

441

Annual review of astronomy and astrophysics. Vol. 30  

NASA Astrophysics Data System (ADS)

The papers presented in this volume focus on such topics as warps, astronomical masers, solar flares and coronal mass ejections, magnetic fields of degenerate stars, and evidence for black holes in stellar binary systems. Other topics discussed include cosmological applications of gravitational lensing, X-ray astronomy missions, long-baseline optical and infrared stellar interferometry, smoothed particle hydrodynamics, and radio emission from normal galaxies. (For individual items see A93-25827 to A93-25845)

Burbidge, Geoffrey; Layzer, David; Sandage, Allan

442

Frequency allocations for passive use of the radio spectrum to make scientific studies  

NASA Technical Reports Server (NTRS)

The paper examines the legal implications of frequency allocations for passive use of the radio spectrum, which refer to receive-only radio services. Such receive-only services refer to the reception of radio signals generated by nonhuman agencies as in radio astronomy or in the search for extraterrestrial intelligence. Juridical interpretations of the public interest and of necessity are applied to these passive services.

Stull, M. A.; Alexander, G.

1976-01-01

443

In ecliptic observations of Jovian radio emissions by Ulysses - Comparison with Voyager results  

NASA Technical Reports Server (NTRS)

During the Ulysses inbound cruise to Jupiter the Unified Radio and Plasma Wave (URAP) experiment observed a variety of the planet's radio components in the frequency range below 1 MHz. Most of these emissions were already detected by the Voyager Radio Astronomy and Plasma Wave experiments, however, with much less sensitivity and different spectral coverage. These different radio components within the URAP dynamic spectra are identified, and their appearance with the previous Voyager observations are compared.

Lecacheux, A.; Pedersen, B. M.; Zarka, PH.; Aubier, M. G.; Desch, M. D.; Farrell, W. M.; Kaiser, M. L.; Macdowall, R. J.; Stone, R. G.

1992-01-01

444

Firefighters' Radios  

NASA Technical Reports Server (NTRS)

Public Technology Inc. asked for NASA assistance to devise the original firefighter's radio. Good short-range radio communications are essential during a fire to coordinate hose lines, rescue victims, and otherwise increase efficiency. Useful firefighting tool is lower cost, more rugged short range two-way radio. Inductorless electronic circuit replaced inductances and coils in radio circuits with combination of transistors and other low-cost components. Substitution promises reduced circuit size and cost. Enhanced electrical performance made radio more durable and improved maintainability by incorporating modular construction.

1976-01-01

445

Astronomy Computer Activities  

NSDL National Science Digital Library

Quia is short for Quintessential Instructional Archive. This site offers a collection of astronomy-based computer activities and quizzes developed by educators for students. Games include concentration (memory), word searches, matching, and flash cards. Topics covered include the nine planets, constellations, stellar evolution, moons, the Messier catalog, and general solar system and astronomical body facts.

446

Extreme Ultraviolet Astronomy  

Microsoft Academic Search

Astronomical studies in the extreme ultraviolet (EUV) band of the spectrum were dismissed during the early years of space astronomy as impossible, primarily because of the mistaken view that radiation in this band would be absorbed by the interstellar medium. Observations in the 1980s from sounding rockets and limited duration orbital spacecraft began to show the potential of this field

Stuart Bowyer; Jeremy J. Drake; Stphane Vennes

2000-01-01

447

Outlook for ultraviolet astronomy  

Microsoft Academic Search

A brief overview of galactic and extragalactic research is given with emphasis on the problems of temperature determination, chemical abundance determination, and the question about the energy sources for the high temperature regions. Stellar astronomy, stellar winds, and the interstellar medium are among the topics covered.

E. Boehm-Vitense

1981-01-01

448

Extreme ultraviolet astronomy  

Microsoft Academic Search

This book on extreme ultraviolet (EUV) astronomy presents an overview of EUV observations and discusses the sources of EUV radiation (including white dwarfs, cool stars, hot stars, cataclysmic variables, compact objects, extragalactic objects, solar system objects, and interstellar medium), interstellar absorption, innovative EUV instrumentation, and future EUV missions. Papers are presented on EUV results from Voyager, an ultrasoft Einstein X-ray

Roger F. Malina; Stuart Bowyer

1991-01-01

449

Neutrino Astronomy Scott Wilbur  

E-print Network

V protons, which should be created with neutrinos, have been seen Can be used to observe possible dark Particle Physics Extremely long baseline for neutrino oscillation studies Dark Matter Searches Many dark Detector Picture from AMANDA II Web Site: http://www.amanda.uci.edu #12;Advantages of Neutrino Astronomy

Golwala, Sunil

450

Astronomy Video Contest  

NASA Astrophysics Data System (ADS)

One of Galileo's staunchest supporters during his lifetime was Johannes Kepler, Imperial Mathematician to the Holy Roman Emperor. Johannes Kepler will be in St. Louis to personally offer a tribute to Galileo. Set Galileo's astronomy discoveries to music and you get the newest song by the well known acappella group, THE CHROMATICS. The song, entitled "Shoulders of Giants was written specifically for IYA-2009 and will be debuted at this conference. The song will also be used as a base to create a music video by synchronizing a person's own images to the song's lyrics and tempo. Thousands of people already do this for fun and post their videos on YOU TUBE and other sites. The ASTRONOMY VIDEO CONTEST will be launched as a vehicle to excite, enthuse and educate people about astronomy and science. It will be an annual event administered by the Johannes Kepler Project and will continue to foster the goals of IYA-2009 for years to come. The Astronomy Video poster will contain all the basic information about the contest including: categories, rules, prizes, web address for more info and how to download the new song, "Shoulders of Giants.

McFarland, John

2008-05-01

451

Astronomy Video Contest  

NASA Astrophysics Data System (ADS)

During Galileo's lifetime his staunchest supporter was Johannes Kepler, Imperial Mathematician to the Holy Roman Emperor. Johannes Kepler will be in St. Louis to personally offer a tribute to Galileo. Set Galileo's astronomy discoveries to music and you get the newest song by the well known acappella group, THE CHROMATICS. The song, entitled "Shoulders of Giants was written specifically for IYA-2009 and will be debuted at this conference. The song will also be used as a base to create a music video by synchronizing a person's own images to the song's lyrics and tempo. Thousands of people already do this for fun and post their videos on YOU TUBE and other sites. The ASTRONOMY VIDEO CONTEST will be launched as a vehicle to excite, enthuse and educate people about astronomy and science. It will be an annual event administered by the Johannes Kepler Project and will continue to foster the goals of IYA-2009 for years to come. During this presentation the basic categories, rules, and prizes for the Astronomy Video Contest will be covered and finally the new song "Shoulders of Giants by THE CHROMATICS will be unveiled

McFarland, John

2008-05-01

452

Astronomy and Shakespeare's Hamlet  

Microsoft Academic Search

Payne-Gaposchkin and others have suggested that Hamlet shows evidence of the Bard's awareness of the astronomical revolutions of the sixteenth century. I summarize major arguments and note that the play's themes recur in modern astronomy teaching and research: (1) The play amounts to a redefinition of universal order and humankind's position in it. (2) There is interplay between appearance and

P. D. Usher

1996-01-01

453

The International Astronomy Olympiad  

NASA Astrophysics Data System (ADS)

The International Astronomy Olympiad (IAO) is an annual scientific-educating event for students of the junior high-school classes, aged 14-18 years. The Euro-Asian Astronomical Society founded the IAO in 1996. The Olympiad includes an intellectual competition between these students. The style of the problems is aimed at developping the imagination, creativity and independent thinking.

Gavrilov, Michael G.

2011-06-01

454

Teaching Astronomy Using Tracker  

ERIC Educational Resources Information Center

A recent paper in this journal presented a set of innovative uses of video analysis for introductory physics using Tracker. In addition, numerous other papers have described how video analysis can be a meaningful part of introductory courses. Yet despite this, there are few resources for using video analysis in introductory astronomy classes. In

Belloni, Mario; Christian, Wolfgang; Brown, Douglas

2013-01-01

455

Das Weltbild der Astronomie  

NASA Astrophysics Data System (ADS)

Inhalt: 1. Das geozentrische Weltbild der Antike und des Mittelalters. 2. Zum heliozentrischen Weltbild. 3. Astronomie und Astrologie. 4. Vom heliozentrischen zum heutigen Weltbild. 5. Die Geburt der Astrophysik. 6. Sterne und Planeten: Das Erschaffen von Neuem. 7. Das Sonnensystem. 8. Galaxien, intergalaktische Materie und die Dunkle Materie. 9. Die Evolution des Universums. 10. Ein spekulativer Blick in den Kosmos.

Nussbaumer, Harry

456

Astronomy 150: The Planets  

NSDL National Science Digital Library

This website contains lab activities on planetary astronomy and the solar system. The labs cover: the earth-moon system, atmospheric escape, craters, meteorites, comets, lunar mapping, Mars, volcanoes on Io, Europa, Neptune, satellites of giant planets, and extra-solar planets.

Palen, Stacy

2004-07-16

457

Colonial American Astronomy  

NASA Astrophysics Data System (ADS)

While a foundation of German scientific methods enabled the rapid growth of North American Astronomy in the nineteenth century, during the seventeenth and most of the eighteenth centuries, the colonial men of science looked only to the English mother country for scientific patronage and guidance. An essay on fundamental astronomy appeared in one of the annual colonial almanacs as early as 1656, telescopic observations were made about 1660 and the first original colonial astronomical work was published by Thomas Danforth on the comet of 1664. By 1671 the Copernican ideas were so espoused at Harvard College that a physics class refused to read a Ptolemaic textbook when it was assigned to them by a senior instructor. At least in the Cambridge-Boston area, contemporary colonialist had access to the most recent scientific publications from the mother country. Observations of the great comet of 1680 by the Almanac maker, John Foster, reached Isaac Newton and were used and gratefully acknowledged in his Principia. During the seventeenth century the colonial interest in astronomy was more intense than it was for other sciences but colonists still occupied a position in the scientific backwater when compared with contemporary European scientists. Nevertheless, the science of astronomy was successfully transplanted from England to North America in the seventeenth century.

Yeomans, Donald K.

2007-12-01

458

History of Astronomy.  

ERIC Educational Resources Information Center

Examines the development of American astronomy by discussing: general studies on the subject; early efforts through 1825; establishing foundations (1825-1875); the transitional period (1875-1945); and the space age (1945 to the present). Points out that the field is underdeveloped with a need for additional work. (JN)

Rothenberg, Marc

1985-01-01

459

Strategies for Teaching Astronomy  

NASA Astrophysics Data System (ADS)

No matter whether you are teaching school children, undergraduates, or colleagues, a few key strategies are always useful. I will present and give examples for the following five key strategies for teaching astronomy. 1. Provide a Contextual Framework: It is much easier to learn new facts or concepts if they can be ``binned" into some kind of pre-existing mental framework. Unless your listeners are already familiar with the basic ideas of modern astronomy (such as the hierarchy of structure in the universe, the scale of the universe, and the origin of the universe), you must provide this before going into the details of how we've developed this modern picture through history. 2. Create Conditions for Conceptual Change: Many people hold misconceptions about astronomical ideas. Therefore we cannot teach them the correct ideas unless we first help them unlearn their prior misconceptions. 3. Make the Material Relevant: It's human nature to be more interested in subjects that seem relevant to our lives. Therefore we must always show students the many connections between astronomy and their personal concerns, such as emphasizing how we are ``star stuff" (in the words of Carl Sagan), how studying other planets helps us understand our own, and so on. 4. Limit Use of Jargon: The number of new terms in many introductory astronomy books is larger than the number of words taught in many first courses in foreign language. This means the books are essentially teaching astronomy in a foreign language, which is a clear recipe for failure. We must find ways to replace jargon with plain language. 5. Challenge Your Students: Don't dumb your teaching down; by and large, students will rise to meet your expectations, as long as you follow the other strategies and practice good teaching.

Bennett, J.

2000-12-01

460

Saturn's variable radio period  

NASA Astrophysics Data System (ADS)

Temporal modulations in radio emissions are often used to determine the rotation rate of the emitting body. The rotation period (presumably) of Jupiter's interior was established in this way [Burke et al., 1962] and has recently been refined by Higgins et al. [1997]. Rotation periods for the remainder of the outer planet gas giants were determined from Voyager planetary radio astronomy observations. Similar techniques have been applied to astrophysical objects, including pulsars, for which the radio period is assumed to be the rotation period of the neutron star. In 2001, however, this simple relation between the radio period and rotation period became suspect, at least for the case of Saturn. Galopeau and Lecacheux [2001] reported that the radio period of Saturn had changed by as much as 1% from that determined by Voyager and, further, exhibited variations on time scales of years. More recently, Cassini observations indicate that the Saturn kilometric radiation is modulated with a period longer than that observed by Voyager and that this period is variable on a time scale of a year or less. The recent Higgins et al. result suggests that Jupiter's period is steady, within measurement accuracy. There are no additional measurements from Uranus or Neptune with which to look for time variations in their radio periods. For conservation of energy and angular momentum reasons, true variations of the rotation period of Saturn's deep interior are not believed to be a viable explanation for the variation in radio period, hence, it would appear that there is some disconnection of the radio period from the rotation period in the case of Saturn. One possible contributing factor may be that since Saturn's magnetic field is very accurately aligned with its rotational axis, there is no first-order beaming effect caused by the wobbling of the magnetic field, contrary to the situation at the other magnetized planets. Another explanation suggested by Galopeau and Lecacheux [2001] and more recently by Cecconi and Zarka [2005] is that variations in the solar wind may affect the period of the radio emissions. Very recently, Giampieri et al. [2006] reported a periodicity in the magnetic field measured by Cassini over a 14-month period that appears to be steady over this time interval. However, the period is consistent, within the 40-s error, with that measured for the radio emissions over the same interval. It appears, then, that the periodicity in the magnetic field is the same as that which has been measured by radio methods for several decades. Since both the radio emission and the magnetic field measurements are based on the field external to the planet, some slippage between the external field and the interior field is suggested. The understanding of the variable period of Saturn's 1 external magnetic field and its relation to the deep interior of the planet is perhaps one of the most fundamental and profound mysteries confronting the Cassini mission at this time. 2

Kurth, W. S.; Lecacheux, A.; Zarka, P.; Gurnett, D. A.; Cecconi, B.

461

Traditional astronomy in India - with special reference to the history of observational astronomy (III).  

NASA Astrophysics Data System (ADS)

The introduction of Islamic astronomy into India and the later history of India astronomy are discussed. Some interesting astronomical instruments were devised during the coexistent period of Hindu astronomy and Islamic astronomy, some of which are described. Lastly, the author's view is presented as to how to consider the coexistence of the traditional astronomy and the modern astronomy in contemporary India.

Ohasi, Y.

1998-10-01

462

Mon. Not. R. Astron. Soc. 421, 15691582 (2012) doi:10.1111/j.1365-2966.2012.20414.x On the fundamental dichotomy in the local radio-AGN population  

E-print Network

data release of the Sloan Digital Sky Survey with the NRAO (National Radio Astronomy Observatory) VLA. Best1 and T. M. Heckman2 1SUPA, Institute for Astronomy, Royal Observatory Edinburgh, Blackford Hill On the fundamental dichotomy in the local radio-AGN population: accretion, evolution and host galaxy properties P. N

Best, Philip

463

Millisecond solar radio spikes observed at 1420 MHz  

NASA Astrophysics Data System (ADS)

We present results from observations of narrowband solar millisecond radio spikes at 1420 MHz. Observing data were collected between February 2000 and December 2001 with the 15-m radio telescope at the Centre for Astronomy Nicolaus Copernicus University in Torun, Poland, equipped with a radio spectrograph that covered the 1352-1490 MHz frequency band. The radio spectrograph has 3 MHz frequency resolution and 80 microsecond time resolution. We analyzed the individual radio spike duration, bandwidth and rate of frequency drift. A part of the observed spikes showed well-outlined subtle structures. On dynamic radio spectrograms of the investigated events we notice complex structures formed by numerous individual spikes known as chains of spikes and distinctly different structure of columns. Positions of active regions connected with radio spikes emission were investigated. It turns out that most of them are located near the center of the solar disk, suggesting strong beaming of the spikes emission.

Dabrowski, B. P.; Kus, A. J.

464

June 18, 2013 1 Department of Astronomy  

E-print Network

June 18, 2013 1 Department of Astronomy Harvard University _________________________________________________________________________________________ Harvard College Observatory 60 Garden Street, MS 46, Cambridge, MA 02138 SpecialAppointmentsintheFASDepartmentofAstronomy Harvard'sprograminastrophysicsisgreatlyenhancedbythealliancebetweentheHarvard Astronomy

465

Strategic Plan Department of Physics and Astronomy  

E-print Network

Strategic Plan Department of Physics and Astronomy University of Tennessee, Knoxville September (Ex Officio), and Hanno Weitering #12;Introduction The Department of Physics and Astronomy has over. Figure 1: Schematic diagram illustrating the Department of Physics and Astronomy's interactions

Dai, Pengcheng

466

Transmission of Babylonian Astronomy to Other Cultures  

NASA Astrophysics Data System (ADS)

Babylonian astronomy and astrology were extensively transmitted to other civilizations in the second and first millennia BC. Greek astronomy in particular was largely shaped by knowledge of Babylonian observations and mathematical astronomy.

Jones, Alexander

467

Kerala School of Astronomy  

NASA Astrophysics Data System (ADS)

It is well known that the Kerala school of astronomy, pioneered by M?dhava in the fourteenth century, made remarkable contributions to the development of calculus. In this chapter, we shall summarize the equally significant contribution made by the Kerala astronomers to the development of planetary theory. By 1500 CE, N?laka??ha Somay?j? came up with a remarkable revision of the traditional Indian planetary theory, in which, for the first time in the History of Astronomy, he arrives at a correct formulation of the equation of center and the latitudinal motion of the interior planets, which in turn makes his model computationally equivalent to the Keplerian theory under certain approximation.

Ramasubramanian, Krishnamurthi

468

Astronomy and astrology  

NASA Astrophysics Data System (ADS)

Astrology meets a large success in our societies, from the private to the political sphere as well as in the media, in spite of the demonstrated inaccuracy of its psychological as well as operational predictions. We analyse here the relations between astrology and astronomy, as well as the criticisms opposed by the latter to the former. We show that most of these criticisms are weak. Much stronger ones emerge from the analysis of the astrological practice compared to the scientific method, leading us to conclude to the non-scientificity of astrology. Then we return to the success of astrology, and from its analysis we propose a renewed (and prophylactic) rle for astronomy in society.

Zarka, Philippe

2011-06-01

469

Astronomy in Antarctica  

NASA Astrophysics Data System (ADS)

Antarctica provides a unique environment for astronomers to practice their trade. The cold, dry and stable air found above the high Antarctic plateau, as well as the pure ice below, offers new opportunities for the conduct of observational astronomy across both the photon and the particle spectrum. The summits of the Antarctic plateau provide the best seeing conditions, the darkest skies and the most transparent atmosphere of any earth-based observing site. Astronomical activities are now underway at four plateau sites: the Amundsen-Scott South Pole Station, Concordia Station at Dome C, Kunlun Station at Dome A and Fuji Station at Dome F, in addition to long duration ballooning from the coastal station of McMurdo, at stations run by the USA, France/Italy, China, Japan and the USA, respectively. The astronomy conducted from Antarctica includes optical, infrared, terahertz and sub-millimetre astronomy, measurements of cosmic microwave background anisotropies, solar astronomy, as well as high energy astrophysics involving the measurement of cosmic rays, gamma rays and neutrinos. Antarctica is also the richest source of meteorites on our planet. An extensive range of site testing measurements have been made over the high plateau sites. In this article, we summarise the facets of Antarctica that are driving developments in astronomy there, and review the results of the site testing experiments undertaken to quantify those characteristics of the Antarctic plateau relevant for astronomical observation. We also outline the historical development of the astronomy on the continent, and then review the principal scientific results to have emerged over the past three decades of activity in the discipline. These range from determination of the dominant frequencies of the 5 min solar oscillation in 1979 to the highest angular scale measurements yet made of the power spectrum of the CMBR anisotropies in 2010. They span through infrared views of the galactic ecology in star formation complexes in 1999, the first clear demonstration that the Universe was flat in 2000, the first detection of polarization in the CMBR in 2002, the mapping of the warm molecular gas across the ~ 300 pc extent of the Central Molecular Zone of our Galaxy in 2003, the measurement of cosmic neutrinos in 2005, and imaging of the thermal Sunyaev Zeldovich effect in galaxy clusters in 2008. This review also discusses how science is conducted in Antarctica, and in particular the difficulties, as well as the advantages, faced by astronomers seeking to bring their experiments there. It also reviews some of the political issues that will be encountered, both at national and international level. Finally, the review discusses where Antarctic astronomy may be heading in the coming decade, in particular plans for infrared and terahertz astronomy, including the new facilities being considered for these wavebands at the high plateau stations.

Burton, Michael G.

2010-10-01

470

Astronomy Training Module  

NSDL National Science Digital Library

This is a lesson about the survival of humans in space. Learners will predict how human survival requirements are met by characteristics of our solar system and planet. They engage in an online Astronomy Training module in which they make changes to the astronomical conditions of our solar system and observe the effects of these changes on Earth. They then draw conclusions about which astronomical conditions are necessary to support human survival. The lesson models scientific inquiry using the 5E instructional model and includes teacher notes, prerequisite concepts, common misconceptions, student journal and reading. This is lesson 2 in the Astro-Venture Astronomy Unit. The lessons are designed for educators to use in conjunction with the Astro-Venture multimedia modules.

471

Astronomy Education and Outreach  

NSDL National Science Digital Library

This site, created by Dr. Gene Smith of the University of California, San Diego, is very useful for a teacher. There are many tutorials, educational sites, curriculum resources and links to other courses. Topics on this page include: telescopes, nuclear energy, solar neutrinos, general relativity, galaxies, quasars, thermal radiation, atomic structure, black holes, dark matter and cosmology. This is a great resource for a general overview of many different topics in astronomy.

Smith, Gene

2009-07-29

472

Astronomy on a Landfill  

NASA Astrophysics Data System (ADS)

Engaging "K-to-Gray audiences (children, families, and older adults) in astronomical activities is one of the main goals of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of IYA 2009 to the approximately 25,000 students and 15,000 adults that visit our site from the NY/NJ region each year. Diversifying our traditional environmental science offerings, we have incorporated astronomy into our repertoire with "The Sun Through Time module, which includes storytelling, cultural astronomy, telescope anatomy, and other activities that are based on the electromagnetic spectrum and our current knowledge of the sun. These lessons have also been modified to bring astronomy to underserved communities, specifically those individuals that have dexterity or cognitive ability differences. The program is conducted in a classroom setting and is designed to meet New Jersey Core Curriculum Content Standards. With the installation of our new 20 telescope, students and amateur astronomers will be given the opportunity to perform rudimentary research. In addition, a program is in development that will allow individuals to measure local sky brightness and understand the effects of light pollution on astronomical viewing. Teaching astronomy in an urban setting presents many challenges. All individuals, regardless of ability level or location, should be given the opportunity to be exposed to the wonders of the universe and the MEC/CESE has been successful in providing those opportunities.

Venner, Laura

2008-09-01

473

Astronomy on a Landfill  

NASA Astrophysics Data System (ADS)

Engaging "K-to-Gray audiences (children, families, and older adults) in astronomical activities is one of the main goals of the NJMC Center for Environmental and Scientific Education and the William D. McDowell Observatory located in Lyndhurst, NJ. Perched atop a closed and reclaimed municipal solid waste landfill, our new LEED - certified building (certification pending) and William D. McDowell observatory will assist in bringing the goals of IYA 2009 to the approximately 25,000 students and 3,000 adults that visit our site from the NY/NJ region each year. Diversifying our traditional environmental science offerings, we have incorporated astronomy into our repertoire with "The Sun Through Time module, which includes storytelling, cultural astronomy, telescope anatomy, and other activities that are based on the electromagnetic spectrum and our current knowledge of the sun. These lessons have also been modified to bring astronomy to underserved communities, specifically those individuals that have dexterity or cognitive ability differences. The program is conducted in a classroom setting and is designed to meet New Jersey Core Curriculum Content Standards. With the installation of our new 20 telescope, students and amateur astronomers will be given the opportunity to perform rudimentary research. In addition, a program is in development that will allow individuals to measure local sky brightness and understand the effects of light pollution on astronomical viewing. Teaching astronomy in an urban setting presents many challenges. All individuals, regardless of ability level or location, should be given the opportunity to be exposed to the wonders of the universe and the MEC/CESE has been successful in providing those opportunities.

Venner, Laura

2008-05-01

474

Submillimetre wave astronomy  

Microsoft Academic Search

Observations in the 100-1000-micron band and the instruments used to obtain them are discussed in contributions to the Submillimeter Wave Astronomy Conference held at Queen Mary College, London, in September 1981. The major subject areas covered are large-scale structure and radiative transfer within interstellar clouds, spectroscopic observations of molecular sources, interstellar chemistry, and submillimeter (SM) instrumentation. Reports are included on

J. E. Beckman; J. P. Phillips

1982-01-01

475

Astronomy in Romanian universities  

NASA Astrophysics Data System (ADS)

In this work we present characteristics of the Romanian higher education related to the study of Astronomy. In spite of Romanian economic problems, opportunities for Bachelor's degree, Master's degree (at "Babes-Bolyai" University of Cluj-Napoca) and Ph.D. degree are provided for students enrolled at the faculties of Mathematics or Physics. General regulations, description of courses, research resources and job opportunities are also described and discussed in this paper.

Barbosu, Mihail

476

Quickly creating interactive astronomy illustrations  

NASA Astrophysics Data System (ADS)

An innate advantage for astronomy teachers is having numerous breathtaking images of the cosmos available to capture students' curiosity, imagination, and wonder. Internet-based astronomy image libraries are numerous and easy to navigate. The Astronomy Picture of the Day, the Hubble Space Telescope image archive, and the NASA Planetary Photojournal are just a few of the many available.1-3 At the same time, computer video projectors and SMART Boards are becoming ever more commonplace in classrooms. Taken together, it has never been easier to bring astronomy directly into classrooms to actively engage students to improve student understanding and motivate student learning.

Slater, Timothy F.

2015-01-01

477

Antenna array characterization via radio interferometry observation of astronomical sources  

E-print Network

We present an in-situ antenna characterization method and results for a "low-frequency" radio astronomy engineering prototype array, characterized over the 75-300 MHz frequency range. The presence of multiple cosmic radio sources, particularly the dominant Galactic noise, makes in-situ characterization at these frequencies challenging; however, it will be shown that high quality measurement is possible via radio interferometry techniques. This method is well-known in the radio astronomy community but seems less so in antenna measurement and wireless communications communities, although the measurement challenges involving multiple undesired sources in the antenna field-of-view bear some similarities. We discuss this approach and our results with the expectation that this principle may find greater application in related fields.

Colegate, T M; Hall, P J; Padhi, S K; Wayth, R B; de Vaate, J G Bij; Crosse, B; Emrich, D; Faulkner, A J; Hurley-Walker, N; Acedo, E de Lera; Juswardy, B; Razavi-Ghods, N; Tingay, S J; Williams, A

2015-01-01

478

Summary of interference measurements at selected radio observatories  

NASA Technical Reports Server (NTRS)

Results are presented from a series of RF interference (RFI) observations conducted during 1989 and 1990 at selected radio astronomy observatories in order to choose a site for the SETI, where the local and orbital RFI would be as benign as possible for observations of weak electromagnetic signals. These observatories included the DSS13 at Goldstone (California), the Arecibo Observatory (Puerto Rico), the Algonquin Radio Observatory in Ottawa (Canada), the Ohio State University Radio Observatory in Columbus (Ohio), and the NRAO in Green Bank (West Virginia). The observations characterize the RFI environment at these sites from 1 to 10 GHz, using radio astronomy antennas, feeds, and receivers; SETI signal processors; and stand-alone equipment built specifically for this purpose. The results served as part of the basis for the selection (by the NASA SETI Microwave Observing Project) of NRAO as the site of choice for SETI observations.

Tarter, Jill C.

1990-01-01

479

Report Of The Cospar WG On "Future Of Space Astronomy"  

NASA Astrophysics Data System (ADS)

The COSPAR President on April 20, 2010 appointed the "Future of Space Astronomy Working Group under the aegis of Commission E, with the aim to analyze the difficult situation of space astronomy over the next two decades and recommend ways to improve the prospects. Having assessed the scientific needs and the current plans of the main space agencies worldwide, the WG has identified some major concerns about the lack of a secured future for Space Astronomy. In fact, astronomers today have access to an impressive set of space missions and ground-based observatories that gives them nearly continuous coverage of the electromagnetic spectrum from the gamma-ray to the radio regions. But the picture becomes concerning and critical in the next 10 - 15 years, when current space astronomy missions will have ended and new missions will be much less numerous. Astronomy is a difficult observational science requiring continuous and simultaneous access to the full electromagnetic spectrum to explore our complex Universe and to pursue answers to fundamental scientific questions. The history of space astronomy, especially the past three decades, has demonstrated clearly the importance and benefits of access to the gamma-ray, X-ray, UV-optical, near IR and far-IR spectrum from space. So far the only planned observatory class missions, proposed to NASA-ESA-JAXA are JWST (2018), WFIRST/EUCLID (2018-2020), Athena (ex IXO, 2022) and LISA. The latter two under re-scope in an ESA alone scenario with a cost <1B. We will present the main WG outcome with a number of recommendations and, finally, suggest a road map for the next decades. *WG membership: Pietro Ubertini (Chair), Italy, Neil Gehrels (Co-Chair), USA, Ian Corbett (IAU liason), UK, Paolo De Bernardis, Italy, Marcos Machado, Argentina, Matt Griffin, UK, Michael Hauser, USA, Ravinder K. Manchanda, India, Nobuyuki Kawai, Japan, Shuang-Nan Zhang, China, Mikhail Pavlinsky, Russia

Ubertini, Pietro; Space Astronomy*, Cospar WG on Future of

2011-09-01

480

Virtual radios  

Microsoft Academic Search

Conventional software radios take advantage of vastly improved analog to digital converters (ADCs) and digital signal processing (DSP) hardware. Our approach, which we refer to as virtual radios, also depends upon high performance ADCs. However, rather than use DSPs, we have chosen to ride the curve of rapidly improving workstation hardware. We use wideband digitization and then perform all of

Vanu Bose; Michael Ismert; Matt Welborn; John Guttag

1999-01-01

481

College Radio.  

ERIC Educational Resources Information Center

As with commercial stations, the underlying premise of the college radio station is to serve the community, whether it be the campus community or the community at large, but in unique ways often geared to underserved niches of the population. Much of college radio's charm lies in its unpredictable nature and constant mutations. The stations give

Sauls, Samuel J.

482

A basic atlas of radio-wave propagation  

NASA Astrophysics Data System (ADS)

Basic concepts in radio-wave propagation and system design are brought together in this volume along with all of the essential design elements required for VHF, UHF, and SHF radio. The basic topics addressed include free-space propagation path, reflection interference propagation path, diffraction propagation path, troposcatter propagation path, absorption propagation path, passive-relay propagation path, noise and S/N, fading estimation and system evaluation, and astronomy and geography.

Shibuya, Shigekazu

483

Improved Estimation Of Delays In Radio Interferometry  

NASA Technical Reports Server (NTRS)

Report describes status of mathematical model of delays in propagation of radio signals that originate at extra-galactic or other distant sources and received at widely separated terrestrial antennas engaged in very-long-baseline interferometry. Implemented in multiparameter estimation computer program MODEST. Needed, in applications as geodynamics and astronomy, to extract significant parameters from observed signal delays. Program and present report are updated versions of MASTERFIT program and accompanying report.

Sovers, Ojars J.

1993-01-01

484

Astronomy & Astrophysics manuscript no. elias c ESO 2012 January 3, 2012  

E-print Network

Astronomy & Astrophysics manuscript no. elias c ESO 2012 January 3, 2012 Photon orbital angular momentum and torque metrics for single telescopes and interferometers N.M. Elias II National Radio ­ techniques: image processing -- techniques: interferometers -- telescopes 1. Introduction Elias (2008

Groppi, Christopher

485

Scientific results and prospects from the 8.2-m Subaru Telescope: extra galactic astronomy  

E-print Network

Deep Field North. Keywords: cluster of galaxies, gravitational lens, radio galaxies, Subaru telescope 2Scientific results and prospects from the 8.2-m Subaru Telescope: extra galactic astronomy M. Iye Telescope had its astronomical first light at the Cassegrain focus in January 1999. Commissioning

Iye, Masanori

486

DETECTION AND BLANKING OF GSM INTERFERENCE IN RADIO-ASTRONOMICAL OBSERVATIONS  

E-print Network

DETECTION AND BLANKING OF GSM INTERFERENCE IN RADIO-ASTRONOMICAL OBSERVATIONS Amir Leshem, Alle, satellite and broad- cast services. In particular, the GSM band is a highly satu- rated domain, full to radio astronomy, and the GSM sys- tem which became ubiquitous and thus prevents observation in its band

van der Veen, Alle-Jan

487

Using Multiple Beams to Distinguish Radio Frequency Interference from SETI Signals  

E-print Network

for extra-terrestrial intelligence) observations. It is a multi-beam instrument, with 16 independently for extraterrestrial intelligence (SETI).1,2 A key element of any RFI mitigation strategy is to discriminate RFI from Array is a multi-user instrument and will perform simultaneous radio astronomy and radio SETI (search

Ellingson, Steven W.

488

Efficient Computation of Prolate Spheroidal Wave Functions in Radio Astronomical Source Modeling  

Microsoft Academic Search

The application of orthonormal basis functions such as Prolate Spheroidal Wave Functions (PSWF) for accurate source modeling in radio astronomy has been comprehensively studied. They are of great importance for high fidelity, high dynamic range imaging with new radio telescopes as well as conventional ones. But the construction of PSWF is computationally expensive compared to other closed form basis functions.

Parisa Noorishad; Sarod Yatawatta

2011-01-01

489

Particle Acceleration and Transport on the Sun New Perspectives at Radio Wavelengths  

E-print Network

Particle Acceleration and Transport on the Sun New Perspectives at Radio Wavelengths An Astro2010. Hudson5 , G. Hurford5 , S. Krucker4 , J. Lee3 , J. Miller6 , S. White7 1 National Radio Astronomy Summary Particle acceleration and particle transport are ubiquitous in astrophysics. The Sun offers

490

Design parameters and measured performance of the IRAM 30-m Millimeter Radio Telescope  

Microsoft Academic Search

The Millimeter Radio Telescope (MRT) is operated by the Institute for Radio Astronomy in the millimeter range (IRAM) and is located at 2850-m altitude in the Sierra Nevada, near Granada, Spain. It is a reflector antenna of 30-m diameter with a surface accuracy of 0.08 mm and a pointing accuracy of better than 2 arcsec. The telescope is equipped with

JACOB W. M. BAARS; ALBERT GREVE; HAUKE HEIN; DAVE MORRIS; JUAN PENALVER; CLEMENS THUM

1994-01-01

491

NRAO Response to NSF Senior Review of Astronomy Facilities  

NASA Astrophysics Data System (ADS)

The National Science Foundation's (NSF) Astronomy Senior Review Committee report (pdf file), released today, made major recommendations for restructuring the NSF's ground-based astronomy efforts, including significant changes for the National Radio Astronomy Observatory (NRAO). The committee's report urged that leadership in radio astronomy, including millimeter- and submillimeter-wave observatories, "remain centered at NRAO as it is, by far, the largest radio astronomy organization in the world." The report praised the record of management of NRAO and the scientific capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA), the Expanded Very Large Array (EVLA), the Robert C. Byrd Green Bank Telescope (GBT), and the Very Long Baseline Array (VLBA). However, the report also recommended that some reductions and changes occur at the NRAO by 2011. Specifically, the report recommended that: (a) VLBA operations make a transition to a significant reliance on international funding or risk closure; (b) GBT operations costs be reduced; and (c) NRAO scientific staff costs be reduced. "The Senior Review Committee had the very difficult task of reconciling the needs of current facilities and funding new facilities for the future of astronomy. We appreciate their efforts and look forward to working with the NSF to ensure that the valuable and unique research capabilities of our NRAO telescopes continue to serve the astronomical community," said Dr. Fred K.Y. Lo, NRAO Director. The VLBA provides the greatest angular resolution, or ability to see fine detail, of any telescope in the world, greatly exceeding the capabilities of the Hubble Space Telescope and the future Square Kilometre Array. The committee recognized that, "if the VLBA is closed, a unique capability would likely be lost for decades." "The VLBA is used by scientists from around the world because of its unique capabilities. It has produced landmark research milestones and the committee recognized in its report that the VLBA now is poised to become even more scientifically productive. We will aggressively pursue international assistance in keeping this world-class research tool operational, and are optimistic that we will succeed," Lo said. The Robert C. Byrd Green Bank Telescope, termed by the committee a "new and highly promising telescope," already has taken the lead in some important research fields. While the committee recommended reductions in the operational costs of the GBT, the NRAO already has been taking steps to make the operations as efficient as possible, commensurate with adequate support for productive science operations. "We look forward to an independent cost analysis by specialists in telescope operations and business administration," Lo said, adding that, "In the meantime, we will redouble efforts to explore alternative modes of operation while continuing to enhance scientific capabilities." The scientific staff of NRAO, composed of Ph.D astronomers, provides scientific guidance for the development and operations of the telescopes, assistance and mentoring to scientists using the telescopes and to students, and serves in key management and operational roles. The expertise embodied in NRAO's staff is a unique resource for planning the next generation of radio astronomy facilities. "As astronomy becomes more reliant on multi-wavelength investigations and NRAO telescopes are used more by researchers unfamiliar with radio observational techniques, the support provided by an excellent scientific staff will become even more important," Lo said. "Throughout this whole process, the NRAO will continue to carry out its mission of enabling cutting-edge research, attracting and training future scientists and engineers, and stimulating public interest in science," Lo said. The NRAO will work closely with the NSF in the coming months as the NSF considers the Senior Review recommendations. "The future of the NRAO is extremely bright," Lo said. "Our sci

2006-11-01

492

Astronomy In Serbia And Montenegro  

NASA Astrophysics Data System (ADS)

A review of professional and amateur astronomy in Serbia and Montenegro is given. After a brief historical survey of the foundations and development of astronomy education in Serbia and Montenegro, special attention is given to a new curriculum that is being prepared for all educational levels.

Atanackovic-Vukmanovic, O.

2006-08-01

493

Science and Mathematics in Astronomy  

NASA Technical Reports Server (NTRS)

A brief historical introduction to the development of observational astronomy will be presented. The close historical relationship between the successful application of mathematical concepts and advances in astronomy will be presented. A variety of simple physical demonstrations, hands-on group activities, and puzzles will be used to understand how the properties of light can be used to understand the contents of our universe.

Woolack, Edward

2009-01-01

494

Animations for Physics and Astronomy  

NSDL National Science Digital Library

This collection of animations illustrates basic concepts in physics and astronomy. Topics include astronomy, mechanics, vectors, electricity and magnetism, waves, optics, and many others. The animations are organized by topic and may be downloaded or streamed from the website. The site also includes links to papers on the use of animations in physics education.

Gallis, Michael R.

495

Astronomy Matters for Chemistry Teachers.  

ERIC Educational Resources Information Center

Describes basic misconceptions about the origin of elements and forms of matter found in chemistry texts that need modification in light of modern observational data and interpretations given in astronomy. Notes that there are forms of matter other than elements and compounds. Confounding examples from astronomy include white dwarfs, neutron

Huebner, Jay S.; And Others

1996-01-01

496

Research Review NOVA and Astronomy  

E-print Network

Research Review NOVA and Astronomy 2010 October 2011 #12;2 QANU / Research Review NOVA NOVA and Astronomy 3 Contents: Update 5 1. The Review Committee and Review Procedures 7 2. Remarks concerning the overall NOVA research school 9 3. General Remarks on the level of the Institutes 15 4

van Rooij, Robert

497

Reports of planetary astronomy, 1991  

NASA Technical Reports Server (NTRS)

A collection is presented of summaries designed to provide information about scientific research projects conducted in the Planetary Astronomy Program in 1990 and 1991, and to facilitate communication and coordination among concerned scientists and interested persons in universities, government, and industry. Highlights of recent accomplishments in planetary astronomy are included.

1991-01-01

498

Dyslexia and Astronomy  

NASA Astrophysics Data System (ADS)

Dyslexia is a hereditary neurological disability that impairs reading. It is believed that anywhere from 5% to 20% of all people in the US may have dyslexia to a greater or lesser degree. Though dyslexia is common, it is a "silent disability" in the sense that it is not easy to tell which individuals suffer from dyslexia and which do not. There is a substantial body of evidence to suggest that people with dyslexia tend to do well in science. For example, Baruj Benacerraf, a Nobel laureate in medicine, is among those whose impairments have been documented and studied. Given that dyslexia was not diagnosed in schools prior to the late 1970's, many established science researchers may have dyslexia and be unaware of their impairment. Therefore, it would not be surprising to find that substantial numbers of scientists working in the fields of astronomy and astrophysics have dyslexia, and yet be unaware of the effects this disability has had on their research. A recently proposed theory by the authors suggests that there may be specific neurological reasons why those with dyslexia may be predisposed to science, and predicts that dyslexia may be associated with enhanced abilities for certain types of visual processing, with special implications for image processing. Our study, funded by the NSF, investigates this hypothesis in the context of astronomy and astrophysics. We expect this work will uncover and document challenges faced by scientists with dyslexia, but perhaps more importantly, lead to an understanding of the strengths these scientists bring to research. The program will serve as a clearing-house of information for scientists and students with dyslexia, and begin to provide mentoring for young people with dyslexia interested in astronomy. Scientists who have reason to believe they may have dyslexia are encouraged to contact the authors.

Schneps, Matthew H.; Greenhill, L. J.; Rose, L. T.

2007-12-01

499

Finding Bent-Double Radio Galaxies: A Case Study in Data Mining I. K. Fodor, E. Cant u-Paz, C. Kamath, N. A. Tang  

E-print Network

) at the National Radio Astronomy Observatory (NRAO), FIRST is scheduled to cover more than 10,000 square degrees the radio equivalent of the Palomar Observatory Sky Survey. Us- ing the Very Large Array (VLAFinding Bent-Double Radio Galaxies: A Case Study in Data Mining #3; I. K. Fodor, E. Cant#19;u

Kamath, Chandrika

500

22. J. M. Weisberg, J. H. Taylor, in Binary Radio Pulsars, F. Rasio, I. H. Stairs, Eds. (Astronomical Society of the  

E-print Network

. The National Radio Astronomy Observatory (NRAO) is a facility of the NSF operated under cooperative agreement22. J. M. Weisberg, J. H. Taylor, in Binary Radio Pulsars, F. Rasio, I. H. Stairs, Eds and N. Wex for useful discussions. The Parkes radio telescope is part of the Australia Telescope, which

Boyce, C. Kevin