Radio Astronomy at TIFR, Some Highlights and Reminiscences
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Probing the Universe at Low Radio Frequencies Using the GMRT
The GMRT : a look at the Past, Present and Future Yashwant Gupta & Govind Swarup National Centre for Radio Astrophysics Pune India URSI GASS Montreal 2017 The GMRT : a look at the Past, Present and Future Yashwant Gupta & Govind Swarup National Centre for Radio Astrophysics Pune India URSI GASS Montreal 2017 Overview of today’s talk . Part I : the GMRT -- a historical perspective . Part II : the GMRT -- current status . Part III : future -- the upgraded GMRT Some history . It is the early 1980s… the VLA has recently become operational . Radio astronomy has shifted from the low frequencies, where it was born, to higher frequencies (cm and higher wavelengths) -- obvious reasons . Note, however, techniques like self-cal have been shown to work . In India, the radio astronomy group at the Tata Institute, under the leadership of Govind Swarup, is looking for the next big challenge… They have already : . Built the Ooty Radio Telescope in the late 1960s – still operational & producing international quality results (in fact, currently being upgraded with new receiver system!) . Built the Ooty Synthesis Radio Telescope (1980s) – short-lived but valuable learnings . Built up considerable experience in low frequencies (metre wavelengths) Birth of the GMRT . Motivation : bridge the gap in radio astronomy facilities at low frequencies and address science problems best studied at metre wavelengths . First concept : 1984 (started with large cylinders); evolved to 34 dishes of 45 metres by 1986 . Project cleared and funding secured by 1987 . Construction started : 1990; first antenna erected : 1992 . First light observations : 1997 – 1998 . Released for world-wide use : 2002 The GMRT : turning it ON Jan 1997 : First fringes with the prototype GMRT correlator Dec 1998 : first light pulsar observation with the GMRT Dedication of the GMRT The Giant Metrewave Radio Telescope was dedicated to the World Scientific Community by the Chairman of TIFR Council, Shri Ratan Tata. -
The Ooty Wide Field Array (OWFA) Is an Upgrade to the ORT, Which Digitizes the Signals from Every 4 Dipoles Along the Feed Line
J. Astrophys. Astr. (0000) 00, 000–000 The Ooty Wide Field Array C. R. Subrahmanya1∗, P. K. Manoharan2†, Jayaram. N. Chengalur3‡ 1 Raman Research Institute, C. V. Raman Avenue, Sadashivnagar,Bengaluru 560080,India. 2 Radio Astronomy Centre, NCRA-TIFR, P. O. Box 8, Ooty 643001, India. 3 NCRA-TIFR, Pune University Campus, Ganeshkhind, Pune 411007,India. Abstract. We describe here an ongoing upgrade to the legacy Ooty Ra- dio Telescope (ORT). The ORT is a cylindrical parabolic cylinder 530mx30m in size operating at a frequency of 326.5 (or z ∼ 3.35 for the HI 21cm line). The telescope has been constructed on a north-south hill slope whose gradient is equal to the latitude of the hill, making it effectively equitorially mounted. The feed con- sists of an array of 1056 dipoles. The key feature of this upgrade is the digitisation and cross-correlation of the signals of every set of 4-dipoles. This converts the ORT into a 264 element interfer- ometer with a field of view of 2◦ × 27.4◦ cos(δ). This upgraded instrument is called the Ooty Wide Field Array (OWFA). This paper briefly describes the salient features of the upgrade, as well as its main science drivers. There are three main science drivers viz. (1) Observations of the large scale distribution of HI in the post-reionisation era (2) studies of the propagation of plasma ir- regularities through the inner heliosphere and (3) blind surveys for transient sources. More details on the upgrade, as well as on the expected science uses can be found in other papers in this special issue. -
History of the Straw
In attaining our ideals, our means should be as pure as the end! 02 Dr Rajendra Prasad KNOWLEDGEPEDIA Staying up there Space Station, around 2025 The Indian Space Research Organisation (ISRO) lost contact with its lunar Within a decade, India wants to have a lander and rover but experts say the Chandrayaan-2 is “95% successful” as the space station up there. The station will help astronauts stay longer in space to mission’s space probe has been put in its orbit around the moon. It can send back conduct experiments. India wants to valuable data that will help ISRO’s future missions. Here’s a look at the missions the launch the space station by 2025 around the time the International Space Station space agency has lined up in the coming years is decommissioned around 2028. China is also planning a large space station in the lower Earth orbit. Origins of the universe Astrosat-2, 2025 India plans to send a second observatory in space. It will be a follow-up mission of Astrosat-1 — India’s first dedicated multi-wavelength space Reaching for the Sun telescope — aimed at looking at the origin of the universe and discover Aditya-1, 2019-2020 new planets. ISRO is finalising a plan for the mission. Aditya-I is India’s first dedicated scientific mission to study the Sun. A 400 kg class space Befriending a solar sibling Drilling with Japan telescope will be inserted into a halo orbit 1.5 million km from the Earth to study the three Mission Venus, 2023 Moon Mission, 2023 layers of the sun — photosphere, chromosphere ISRO is planning a mission to the Earth’s ISRO and Japan Aerospace Exploration Agency and corona, the outer atmosphere of the star in “twin sister” – Venus. -
Concept Note Indo-South African Flagship Programme in Astronomy
Concept Note Indo-South African Flagship Programme in Astronomy Preamble: The Indo-South Africa Flagship Workshop meetings took place at the Indian Institute of Astrophysics, Bangalore on 15th-16th September 2014, and at the Inter-University Centre for Astronomy and Astrophysics, Pune on 19th September, 2014 and were sanctioned by the Departments of Science and Technology of both countries. A list of participants is included in the appendix. 1. Introduction India and South Africa share common aspirations for scientific and technological development, and for the growth of human capital resources. The countries are members of the BRICS consortium, and have a current bi-lateral agreement to foster joint progress. Their shared goals are particularly apparent in the area of astronomy and astrophysics. Indo-African astronomy cooperation began with projects in radio astronomy in Nigeria and Mauritius in the 1980s, and the optical Nainital-Cape Survey, started in 1997. The Inter-University Centre for Astronomy and Astrophysics (IUCAA) joined SALT in 2007, and the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research (NCRA) has recently joined the SKA. Astronomy captures the imagination of people everywhere, and touches a fundamental human desire to understand the universe that surrounds us and our place in it. It provides an ideal way to attract young learners into scientific and technical studies, developing the human capacity for the knowledge-based economy of the future. Its appeal transcends boundaries of class and race and speaks to all members of our societies. The goal of the Indo-South African Flagship Programme in Astronomy is to exploit these basic strengths for the mutual betterment of our peoples. -
Pulsar Timing Array Experiments 3
Pulsar Timing Array Experiments J. P. W. Verbiest∗, S. Osłowski and S. Burke-Spolaor Abstract Pulsar timing is a technique that uses the highly stable spin periods of neutron stars to investigate a wide range of topics in physics and astrophysics. Pul- sar timing arrays (PTAs) use sets of extremely well-timed pulsars as a Galaxy-scale detector with arms extendingbetween Earth and each pulsar in the array.These chal- lenging experiments look for correlated deviations in the pulsars’ timing that are caused by low-frequency gravitational waves (GWs) traversing our Galaxy. PTAs are particularly sensitive to GWs at nanohertz frequencies, which makes them com- plementary to other space- and ground-based detectors. In this chapter, we will de- scribe the methodology behind pulsar timing; provide an overview of the potential uses of PTAs; and summarise where current PTA-based detection efforts stand. Most predictions expect PTAs to successfully detect a cosmological background of GWs emitted by supermassive black-hole binaries and also potentially detect continuous- wave emission from binary supermassive black holes, within the next several years. J. P. W. Verbiest Fakult¨at f¨ur Physik, Universit¨at Bielefeld, Postfach 100131, 33501 Bielefeld, Germany and Max-Planck-Institut f¨ur Radioastronomie, Auf dem H¨ugel 69, 53121 Bonn, Germany, e-mail: [email protected] S. Osłowski Centre for Astrophysics and Supercomputing, Swinburne University of Technology, PO Box 218, Hawthorn, VIC 3122, Australia, e-mail: [email protected] S. Burke-Spolaor Department of Physics and Astronomy, West Virginia University, P.O. Box 6315, Morgantown, arXiv:2101.10081v1 [astro-ph.IM] 25 Jan 2021 WV 26506, USA and Center for Gravitational Waves and Cosmology, West Virginia University, Chestnut Ridge Re- search Building, Morgantown, WV 26505, USA and Canadian Institute for Advanced Research, CIFAR Azrieli Global Scholar, MaRS Cen- tre West Tower, 661 University Ave. -
INDIA JANUARY 2018 – June 2020
SPACE RESEARCH IN INDIA JANUARY 2018 – June 2020 Presented to 43rd COSPAR Scientific Assembly, Sydney, Australia | Jan 28–Feb 4, 2021 SPACE RESEARCH IN INDIA January 2018 – June 2020 A Report of the Indian National Committee for Space Research (INCOSPAR) Indian National Science Academy (INSA) Indian Space Research Organization (ISRO) For the 43rd COSPAR Scientific Assembly 28 January – 4 Febuary 2021 Sydney, Australia INDIAN SPACE RESEARCH ORGANISATION BENGALURU 2 Compiled and Edited by Mohammad Hasan Space Science Program Office ISRO HQ, Bengalure Enquiries to: Space Science Programme Office ISRO Headquarters Antariksh Bhavan, New BEL Road Bengaluru 560 231. Karnataka, India E-mail: [email protected] Cover Page Images: Upper: Colour composite picture of face-on spiral galaxy M 74 - from UVIT onboard AstroSat. Here blue colour represent image in far ultraviolet and green colour represent image in near ultraviolet.The spiral arms show the young stars that are copious emitters of ultraviolet light. Lower: Sarabhai crater as imaged by Terrain Mapping Camera-2 (TMC-2)onboard Chandrayaan-2 Orbiter.TMC-2 provides images (0.4μm to 0.85μm) at 5m spatial resolution 3 INDEX 4 FOREWORD PREFACE With great pleasure I introduce the report on Space Research in India, prepared for the 43rd COSPAR Scientific Assembly, 28 January – 4 February 2021, Sydney, Australia, by the Indian National Committee for Space Research (INCOSPAR), Indian National Science Academy (INSA), and Indian Space Research Organization (ISRO). The report gives an overview of the important accomplishments, achievements and research activities conducted in India in several areas of near- Earth space, Sun, Planetary science, and Astrophysics for the duration of two and half years (Jan 2018 – June 2020). -
Great Discoveries Made by Radio Astronomers During the Last Six Decades and Key Questions Today
17_SWARUP (G-L)chiuso_074-092.QXD_Layout 1 01/08/11 10:06 Pagina 74 The Scientific Legacy of the 20th Century Pontifical Academy of Sciences, Acta 21, Vatican City 2011 www.pas.va/content/dam/accademia/pdf/acta21/acta21-swarup.pdf Great Discoveries Made by Radio Astronomers During the Last Six Decades and Key Questions Today Govind Swarup 1. Introduction An important window to the Universe was opened in 1933 when Karl Jansky discovered serendipitously at the Bell Telephone Laboratories that radio waves were being emitted towards the direction of our Galaxy [1]. Jansky could not pursue investigations concerning this discovery, as the Lab- oratory was devoted to work primarily in the field of communications. This discovery was also not followed by any astronomical institute, although a few astronomers did make proposals. However, a young electronics engi- neer, Grote Reber, after reading Jansky’s papers, decided to build an inno- vative parabolic dish of 30 ft. diameter in his backyard in 1935 and made the first radio map of the Galaxy in 1940 [2]. The rapid developments of radars during World War II led to the dis- covery of radio waves from the Sun by Hey in 1942 at metre wavelengths in UK and independently by Southworth in 1942 at cm wavelengths in USA. Due to the secrecy of the radar equipment during the War, those re- sults were published by Southworth only in 1945 [3] and by Hey in 1946 [4]. Reber reported detection of radio waves from the Sun in 1944 [5]. These results were noted by several groups soon after the War and led to intensive developments in the new field of radio astronomy. -
Arxiv:1507.08236V1 [Astro-Ph.IM] 27 Jul 2015
ApJL, in press Preprint typeset using LATEX style emulateapj v. 5/2/11 MURCHISON WIDEFIELD ARRAY OBSERVATIONS OF ANOMALOUS VARIABILITY: A SERENDIPITOUS NIGHT-TIME DETECTION OF INTERPLANETARY SCINTILLATION D. L. Kaplan1, S. J. Tingay2,3, P. K. Manoharan4, J.-P. Macquart2,3, P. Hancock2,3, J. Morgan2, D. A. Mitchell5,3, R. D. Ekers5, R. B. Wayth2,3, C. Trott2,3, T. Murphy6,3, D. Oberoi4, I. H. Cairns6, L. Feng7, N. Kudryavtseva2, G. Bernardi8,9,10, J. D. Bowman11, F. Briggs12, R. J. Cappallo13, A. A. Deshpande14, B. M. Gaensler6,3,15, L. J. Greenhill10, N. Hurley-Walker2, B. J. Hazelton16, M. Johnston-Hollitt17, C. J. Lonsdale13, S. R. McWhirter13, M. F. Morales16, E. Morgan7, S. M. Ord2,3, T. Prabu14, N. Udaya Shankar14, K. S. Srivani14, R. Subrahmanyan14,3, R. L. Webster18,3, A. Williams2, and C. L. Williams7 ApJL, in press ABSTRACT We present observations of high-amplitude rapid (2 s) variability toward two bright, compact ex- tragalactic radio sources out of several hundred of the brightest radio sources in one of the 30◦ 30◦ MWA Epoch of Reionization fields using the Murchison Widefield Array (MWA) at 155 MHz.× After rejecting intrinsic, instrumental, and ionospheric origins we consider the most likely explanation for this variability to be interplanetary scintillation (IPS), likely the result of a large coronal mass ejection propagating from the Sun. This is confirmed by roughly contemporaneous observations with the Ooty Radio Telescope. We see evidence for structure on spatial scales ranging from <1000 km to > 106 km. The serendipitous night-time nature of these detections illustrates the new regime that the MWA has opened for IPS studies with sensitive night-time, wide-field, low-frequency observations. -
LIST of PARTICIPANTS ABRAMOWICZ,M.A., International
LIST OF PARTICIPANTS ABRAMOWICZ,M.A., International Centre for Advanced Studies.Trieste,Italy AGRAWAL,P.C., Tata Institute of Fundamental Research.Bombay 400005,India ALIGHIERI,S.di S., ST-ECF, ESO, Garching bei München, West Germany ALLADIN,S.M., CASA, Osmania University, Hyderabad 500007, India ALL0IN,D., Observatoire de Meudon, Meudon Principal Cedex, France ANANTHAKRISHNAN,S., Radio Astronomy Centre(TIFR),0otacamund 643001,India ANANTHARAMIAH,Κ., Raman Research Institute, Bangalore 560080, India ANDERSON,M., Institute of Astronomy,Madingley Road, Cambridge CB3 OHE,UK BAILEY,J., Anglo Australian Observatory, Epping, NSW 2121, Australia BALDWIN,J.Ε., Cavendish Laboratory,Madingley Road,Cambridge CB3 OHE, UK BARR,P., European Southern Observatory, 6100 Darmstadt, West Germany BARTEL,N., Centre for Astrophysics, 60 Garden Street, Cambridge, Ma,USA BARTHEL,Ρ.D., Owens Valley Radio Obs., Caltech, Pasadena, Ca 91125, USA BARVAINIS,R., NRAO, Edgemont Road, Charlottesville, Va 22903, USA BERGERON,J.A., Institute d'Astrophysique, 98 Bis.bd. Arago, Paris BHATTACHARYA,D., Raman Research Institute, Bangalore 560080, India BHATTACHARYYA,J.C., Indian Inst, of Astrophysics,Bangalore 560034,India BHAVSAR,S., Raman Research Institute, Bangalore 560080, India BIRKINSHAW,M., Dept. Astronomy, Harvard University, Cambridge, Ma, USA BLADES,J.C, Space Telescope Science Institute, Baltimore, Md 21218,USA BLANDFORD,R.D., Theoretical Astrophysics, Caltech,Pasadena,Ca 91125,USA BOKSENBERG, A. , Royal Greenwich Obs., Hausham, E.Sussex BN27 1RP, UK BRAMWELL,D., National Inst, for Telecomm. Research,Johannesburg,S.Africa BREGMAN,J.N., NRAO, Edgemont Road, Charlottesville, Va 22903, USA BR0DIE,J.P., University of California, Sp.Sc.Lab, Berkeley,Ca 94720,USA BURBIDGE,G.R., Univ. of California, San Diego, La Jolla, Ca 92093, USA BURKE,B.F., Dept. -
M. M. Bisi(I), B
IPIPSS oobbserservavationstions ofof tthhee innerinner--helioheliosspherpheree anandd theirtheir ccomomppaarisrisoonn wwiithth multi-multi-popointint in-in-ssituitu mmeaeassurementsurements M. M. Bisi(i), B. V. Jackson(i), A. R. Breen(ii), R. A. Fallows(ii), J. Feynman(iii), J. M. Clover(i), P. P. Hick(i), and A. Buffington(i) (i)(i) CCenenteterr foforr AsAstrotrophyphyssicicss aandnd SSpacpacee ScScieiencncees,s, UUnivniveerrsisityty ofof CCalifoaliforrnia,nia, SSanan DDieiego,go, USAUSA (ii)(ii) InsInstittituteute ofof MatheMathematicmaticaall aandnd PPhyhyssicicalal ScScieiencncees,s, AAbeberryysstwtwyythth UnUniviveersrsiityty,, WaleWaless,, GBGB ((iiii)ii) JJeett PrPropulsopulsiionon LaborLaboraatortoryy,, CCalifaliforornia,nia, USAUSA AAbbsstratracctt Interplanetary scintillation (IPS) observations of the inner-heliosphere have been carried out on a routine basis for many years using metre-wavelength radio telescope arrays. By employing a kinematic model of the solar wind, we reconstruct the three-dimensional (3D) structure of the inner-heliosphere from multiple observing lines of sight. From these reconstructions we extract solar wind parameters such as velocity and density, and compare these to ªground truthº measurements from multi-point in situ solar wind measurements from ACE, Ulysses, STEREO, and the Wind spacecraft, particularly during the International Heliophysical Year (IHY). These multi-point comparisons help us improve our 3D reconstruction technique. Because our observations show heliospheric structures globally, this leads to a better understanding of the structure and dynamics of the interplanetary environment around these spacecraft. 11.. IIntenterrpplalanneetataryry SSccinintillatillattioionn Interplanetary Density irregularities carried out by the Two-station IPS measurements are solar wind modulate the signal from a Scintillation (IPS) is where simultaneous observations distant radio source, e.g. Quasar. the rapid variation in are made of the same source by radio signal from a widely separated antennas. -
Beyond Astrosat: Astronomy Missions Under Review
J. Astrophys. Astr. (2021) 42:78 Ó Indian Academy of Sciences https://doi.org/10.1007/s12036-021-09744-0Sadhana(0123456789().,-volV)FT3](0123456789().,-volV) BEYOND ASTROSAT Beyond AstroSat: Astronomy missions under review P. SREEKUMAR1,2,* and V. KOTESWARA RAO3 1Indian Space Research Organisation, Antariksh Bhavan, New BEL Road, Bengaluru 560 094, India. 2Indian Institute of Astrophysics, II Block, Koramangala, Bengaluru 560 034, India. 3U. R. Rao Satellite Centre, Bengaluru 560 017, India. *Corresponding Author. E-mail: [email protected] MS received 20 November 2020; accepted 30 March 2021 Abstract. India has an expanding program in using space as a platform for research. Astrophysics research from satellites increasingly complement ground-based observations with unique wavelength coverage, more frequent temporal coverage and diffraction-limited observations. India’s first dedicated space astronomy mission, AstroSat has completed five years in orbit and continues to generate important results. Most onboard systems are healthy and the mission is expected to continue to operate for many more years. Plans for space astronomy missions beyond AstroSat, are under discussion for some time. These are based on responses from the Indian research community to an announcement of Opportunity call in early 2018. Here we discuss, an outline of the science focus of future space astronomy missions, under consideration. Keywords. Space astronomy—AstroSat—Indian space missions. 1. Introduction detectors). AstroSat’s unique proposal-driven obser- vational program was a new experience for ISRO. It was With the advent of India’s space program in the 60’s, also designed to respond quickly to Target-of-Oppor- the country has sustained a modest but expanding tunities when unexpected events/states occurring in program in space astronomy. -
Science Technology and 10.9
SCIENCE AND TECHNOLOGY Table of Contents 1. BIOTECHNOLOGY ___________________ 3 4. IT & COMPUTER ___________________ 22 1.1. DNA Technology (Use and Application) 4.1. Data Protection ___________________ 22 Regulation Bill ________________________ 3 4.2. Net Neutrality ____________________ 22 1.2. Human Microbiome ________________ 3 4.3. 5G ______________________________ 23 1.3. Gene Editing ______________________ 4 4.4. Digital Initiatives __________________ 23 1.4. Earth Biogenome Project ____________ 4 4.4.1. National Digital Literacy Mission _______ 23 2. SPACE TECHNOLOGY ________________ 6 4.4.2. Digital Village Programme ____________ 23 2.1. ISRO _____________________________ 6 4.4.3. Digital North-East Vision 2022 _________ 24 2.1.1. Gaganyaan Mission __________________ 6 4.4.4. Digital Payment ____________________ 24 2.1.2. GSAT-11 ___________________________ 6 4.5. Cryptocurrency ___________________ 25 2.1.3. Hyperspectral Imaging Satellite (HYSIS) __ 7 4.6. Artificial Intelligence _______________ 26 2.1.4. Satellite Launch Vehicles by ISRO _______ 7 4.7. Supercomputer ___________________ 27 2.1.5. Young Scientist Programme (YUVIKA) ___ 8 4.8. Cyber-Physical Systems _____________ 28 2.2. NASA Missions in News _____________ 8 4.9. Paris Call _________________________ 29 2.3. Other Space Missions in News _______ 10 4.10. Gravityrat Malware _______________ 29 2.4. Plan to Prevent Asteroid Attack ______ 12 5. HEALTH _________________________ 31 2.5. Other Space Related Development in 5.1. Food and Health __________________ 31 India _______________________________ 12 5.1.1. Food Fortification ___________________ 31 2.5.1. India-Based Neutrino Observatory _____ 12 5.1.2. Eat Right India Movement ____________ 31 2.5.2.