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A Comprehensive Field Guide to the Ngc Volume 1: Autumn/Winter (Andromeda-Eridanus)

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A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 1: AUTUMN/WINTER (ANDROMEDA-ERIDANUS) BHAVESH JIVAN-KALA PAREKH A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 2: AUTUMN/WINTER (FORNAX-VOLANS) BHAVESH JIVAN-KALA PAREKH A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 3: SPRING/SUMMER (ANTILA-INDUS) BHAVESH JIVAN-KALA PAREKH A COMPREHENSIVE FIELD GUIDE TO THE NGC VOLUME 4: SPRING/SUMMER (LEO-VULPECULA) BHAVESH JIVAN-KALA PAREKH Front Cover images: Vol 1: NGC 772/ARP 78 Vol 2: NGC 7317-18-19-20 Stephen’s Quintet Vol 3: NGC 4038-39/ARP 244 Antennae Galaxies Vol 4: NGC 5679/ARP 274 Galaxy Triplet Three of the galaxies in this famous grouping, Stephan's Quintet, A beautiful composite image of two colliding galaxies, the A system of three galaxies that appear to be partially overlapping in NGC 772, a spiral galaxy, has much in common with our home are distorted from their gravitational interactions with one another. Antennae galaxies, located about 62 million light-years from Earth. the image, although they may be at somewhat different distances. galaxy, the Milky Way. Each boasts a few satellite galaxies, small One member of the group, NGC 7320 (upper right) is actually The Antennae galaxies take their name from the long antenna-like The spiral shapes of two of these galaxies appear mostly intact. galaxies that closely orbit and are gravitationally bound to their seven times closer to Earth than the rest. "arms," seen in wide-angle views of the system. These features The third galaxy (to the far left) is more compact, but shows were produced by tidal forces generated in the collision, which parent galaxies. One of NGC 772’s spiral arms has been distorted CREDITS: NASA , ESA , and the Hubble SM4 ERO Team evidence of star formation. Two of the three galaxies are forming began more than 100 million years ago and is still occurring. and disrupted by one of these satellites (NGC 770 — not visible in new stars at a high rate. This is evident in the bright blue knots of The collision has triggered the formation of millions of stars in star formation that are strung along the arms of the galaxy on the the image here), leaving it elongated and asymmetrical. clouds of dust and gas in the galaxies. The most massive of these right and along the small galaxy on the left. young stars have already sped through their evolution in a few However, the two are also different in a few key ways. For one, NGC The largest component is located in the middle of the three. It million years and exploded as supernovas. appears as a spiral galaxy, which may be barred. The entire system 772 is both a peculiar and an unbarred spiral galaxy; respectively, Many of the fainter objects in the optical image are clusters resides at about 400 million light-years away from Earth in the this means that it is somewhat odd in size, shape or composition, containing thousands of stars. constellation Virgo. A pair of foreground stars inside our own Milky and that it lacks a central feature known as a bar, which we see in Way are at far right. This is a composite image from the Chandra X-ray Observatory many galaxies throughout the cosmos — including the Milky Way. (blue), the Hubble Space Telescope (gold and brown), and the CREDITS: NASA, ESA, M. Livio and the Hubble Heritage Team (STScI /AURA ) These bars are built of gas and stars, and are thought to funnel and Spitzer Space Telescope (red). transport material through the galactic core, possibly fueling and CREDITS: NASA , ESA , SAO, CXC, JPL-Caltech, and STScI ; igniting various processes such as star formation. Acknowledgment: J. DePasquale (Harvard-Smithsonian CfA), and B. Whitmore (STScI ) CREDITS: Image: ESA/Hubble & NASA, A. Seth et al. 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  • III. Characteristics of Group Central Radio Galaxies in the Local Universe

    III. Characteristics of Group Central Radio Galaxies in the Local Universe

    MNRAS 489, 2488–2504 (2019) doi:10.1093/mnras/stz2082 Advance Access publication 2019 July 30 The complete local volume groups sample – III. Characteristics of group central radio galaxies in the Local Universe Konstantinos Kolokythas,1‹ Ewan O’Sullivan ,2 Huib Intema ,3,4 Somak Raychaudhury ,1,5,6 Arif Babul,7,8 Simona Giacintucci9 and Myriam Gitti10,11 1Inter-University Centre for Astronomy and Astrophysics, Pune University Campus, Ganeshkhind, Pune, Maharashtra 411007, India 2Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA 3International Centre for Radio Astronomy Research, Curtin University, Bentley, WA 6102, Australia 4 Leiden Observatory, Leiden University, Niels Bohrweg 2, 2333 CA Leiden, the Netherlands Downloaded from https://academic.oup.com/mnras/article/489/2/2488/5541074 by guest on 23 September 2021 5School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, UK 6Department of Physics, Presidency University, 86/1 College Street, Kolkata 700073, India 7Department of Physics and Astronomy, University of Victoria, Victoria, BC V8P 1A1, Canada 8Center for Theoretical Astrophysics and Cosmology, Institute for Computational Science, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland 9Naval Research Laboratory, 4555 Overlook Avenue SW, Code 7213, Washington, DC 20375, USA 10Dipartimento di Fisica e Astronomia, Universita´ di Bologna, via Gobetti 93/2, 40129 Bologna, Italy 11INAF, Istituto di Radioastronomia di Bologna, via Gobetti 101, 40129 Bologna, Italy Accepted 2019 July 22. Received 2019 July 17; in original form 2019 May 31 ABSTRACT Using new 610 and 235 MHz observations from the giant metrewave radio telescope (GMRT) in combination with archival GMRT and very large array (VLA) survey data, we present the radio properties of the dominant early-type galaxies in the low-richness subsample of the complete local-volume groups sample (CLoGS; 27 galaxy groups) and provide results for the radio properties of the full CLoGS sample for the first time.
  • A Search for Transiting Extrasolar Planets in the Open Cluster NGC 4755

    A Search for Transiting Extrasolar Planets in the Open Cluster NGC 4755

    ResearchOnline@JCU This file is part of the following reference: Jayawardene, Bandupriya S. (2015) A search for transiting extrasolar planets in the open cluster NGC 4755. DAstron thesis, James Cook University. Access to this file is available from: http://researchonline.jcu.edu.au/41511/ The author has certified to JCU that they have made a reasonable effort to gain permission and acknowledge the owner of any third party copyright material included in this document. If you believe that this is not the case, please contact [email protected] and quote http://researchonline.jcu.edu.au/41511/ A SEARCH FOR TRANSITING EXTRASOLAR PLANETS IN THE OPEN CLUSTER NGC 4755 by Bandupriya S. Jayawardene A thesis submitted in satisfaction of the requirements for the degree of Doctor of Astronomy in the Faculty of Science, Technology and Engineering June 2015 James Cook University Townsville - Australia i STATEMENT OF ACCESS I the undersigned, author of this work, understand that James Cook University will make this thesis available for use within the University Library and, via the Australian Digital Thesis network, for use elsewhere. I understand that, as an unpublished work, a thesis has significant protection under the Copyright Act and; I do not wish to place any further restriction on access to this work. 2 STATEMENT OF SOURCES DECLARATION I declare that this thesis is my own work and has not been submitted in any form for another degree or diploma at any University or other institution of tertiary education. Information derived from the published or unpublished work of others has been acknowledged in the text and list of references is given.
  • Distant Arm - NGC772

    Distant Arm - NGC772

    29 September 2016, Zeiss Cas 150/2250 Distant Arm - NGC772 Telescope: Zeiss Cassegrain 150/2250 Eyepieces: ATC53P - ATC Plossl, f=53mm, (42×, 530) ATC20K - ATC Kellner, f=20mm, (113×, 220) A-16 - Zeiss Abbe Ortho, f=16mm, (141×, 200) O-12.5 - CZJ Ortho, f=12.5mm, (180×, 140) Time: 2016/09/29 19:30-21:40UT Location: R´ıˇcanyˇ Weather: Clear sky with slight haze and decaying small thin clouds. Mount: Zeiss 1b Accessories: Baader/Zeiss T2 prism This was my typical backyard session. I could go out only for a short time after I put all three kids in to their beds. The night was still warm. Normally, I would try to take an advantage of it and go to some darker place. As I was alone with the kids for the whole week I was bound to stay in our backyard. During last couple of years, I have learnt to live with this handicap. There is always something interesting to look at, even with small refractors. Recently, I was explor- ing the capability of my largest telescope, 150mm Cassegrain. For this night, the main targets were two galaxies, NGC 660 and NGC 772, which I had troubles to locate two days before in 80mm refractor. I was curios how much of help the larger telescope would be. I did not jump to these two galaxies im- mediately. They were still low in the slight haze enhanced by the street lamps. I started a little bit higher in Andromeda with beau- tiful edge-on galaxy NGC 891 (V=10.0, 13:50 ×2:50, PA22◦).