WASP Page 1 Hubble Eyes Aging Stars Science News, Vol. 148
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Messier Objects
Messier Objects From the Stocker Astroscience Center at Florida International University Miami Florida The Messier Project Main contributors: • Daniel Puentes • Steven Revesz • Bobby Martinez Charles Messier • Gabriel Salazar • Riya Gandhi • Dr. James Webb – Director, Stocker Astroscience center • All images reduced and combined using MIRA image processing software. (Mirametrics) What are Messier Objects? • Messier objects are a list of astronomical sources compiled by Charles Messier, an 18th and early 19th century astronomer. He created a list of distracting objects to avoid while comet hunting. This list now contains over 110 objects, many of which are the most famous astronomical bodies known. The list contains planetary nebula, star clusters, and other galaxies. - Bobby Martinez The Telescope The telescope used to take these images is an Astronomical Consultants and Equipment (ACE) 24- inch (0.61-meter) Ritchey-Chretien reflecting telescope. It has a focal ratio of F6.2 and is supported on a structure independent of the building that houses it. It is equipped with a Finger Lakes 1kx1k CCD camera cooled to -30o C at the Cassegrain focus. It is equipped with dual filter wheels, the first containing UBVRI scientific filters and the second RGBL color filters. Messier 1 Found 6,500 light years away in the constellation of Taurus, the Crab Nebula (known as M1) is a supernova remnant. The original supernova that formed the crab nebula was observed by Chinese, Japanese and Arab astronomers in 1054 AD as an incredibly bright “Guest star” which was visible for over twenty-two months. The supernova that produced the Crab Nebula is thought to have been an evolved star roughly ten times more massive than the Sun. -
Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
The Dynamical State of the Coma Cluster with XMM-Newton?
A&A 400, 811–821 (2003) Astronomy DOI: 10.1051/0004-6361:20021911 & c ESO 2003 Astrophysics The dynamical state of the Coma cluster with XMM-Newton? D. M. Neumann1,D.H.Lumb2,G.W.Pratt1, and U. G. Briel3 1 CEA/DSM/DAPNIA Saclay, Service d’Astrophysique, L’Orme des Merisiers, Bˆat. 709, 91191 Gif-sur-Yvette, France 2 Science Payloads Technology Division, Research and Science Support Dept., ESTEC, Postbus 299 Keplerlaan 1, 2200AG Noordwijk, The Netherlands 3 Max-Planck Institut f¨ur extraterrestrische Physik, Giessenbachstr., 85740 Garching, Germany Received 19 June 2002 / Accepted 13 December 2002 Abstract. We present in this paper a substructure and spectroimaging study of the Coma cluster of galaxies based on XMM- Newton data. XMM-Newton performed a mosaic of observations of Coma to ensure a large coverage of the cluster. We add the different pointings together and fit elliptical beta-models to the data. We subtract the cluster models from the data and look for residuals, which can be interpreted as substructure. We find several significant structures: the well-known subgroup connected to NGC 4839 in the South-West of the cluster, and another substructure located between NGC 4839 and the centre of the Coma cluster. Constructing a hardness ratio image, which can be used as a temperature map, we see that in front of this new structure the temperature is significantly increased (higher or equal 10 keV). We interpret this temperature enhancement as the result of heating as this structure falls onto the Coma cluster. We furthermore reconfirm the filament-like structure South-East of the cluster centre. -
Astroph0807.3345 Ful
Draft version July 22, 2008 A Preprint typeset using LTEX style emulateapj v. 08/13/06 THE INVISIBLES: A DETECTION ALGORITHM TO TRACE THE FAINTEST MILKY WAY SATELLITES S. M. Walsh1, B. Willman2, H. Jerjen1 Draft version July 22, 2008 ABSTRACT A specialized data mining algorithm has been developed using wide-field photometry catalogues, en- abling systematic and efficient searches for resolved, extremely low surface brightness satellite galaxies in the halo of the Milky Way (MW). Tested and calibrated with the Sloan Digital Sky Survey Data Release 6 (SDSS-DR6) we recover all fifteen MW satellites recently detected in SDSS, six known MW/Local Group dSphs in the SDSS footprint, and 19 previously known globular and open clusters. In addition, 30 point source overdensities have been found that correspond to no cataloged objects. The detection efficiencies of the algorithm have been carefully quantified by simulating more than three million model satellites embedded in star fields typical of those observed in SDSS, covering a wide range of parameters including galaxy distance, scale-length, luminosity, and Galactic latitude. We present several parameterizations of these detection limits to facilitate comparison between the observed Milky Way satellite population and predictions. We find that all known satellites would be detected with > 90% efficiency over all latitudes spanned by DR6 and that the MW satellite census within DR6 is complete to a magnitude limit of MV ≈−6.5 and a distance of 300 kpc. Assuming all existing MW satellites contain an appreciable old stellar population and have sizes and luminosities comparable to currently known companions, we predict a lower limit total of 52 Milky Way dwarf satellites within ∼ 260 kpc if they are uniformly distributed across the sky. -
From Messier to Abell: 200 Years of Science with Galaxy Clusters
Constructing the Universe with Clusters of Galaxies, IAP 2000 meeting, Paris (France) July 2000 Florence Durret & Daniel Gerbal eds. FROM MESSIER TO ABELL: 200 YEARS OF SCIENCE WITH GALAXY CLUSTERS Andrea BIVIANO Osservatorio Astronomico di Trieste via G.B. Tiepolo 11 – I-34131 Trieste, Italy [email protected] 1 Introduction The history of the scientific investigation of galaxy clusters starts with the XVIII century, when Charles Messier and F. Wilhelm Herschel independently produced the first catalogues of nebulæ, and noticed remarkable concentrations of nebulæ on the sky. Many astronomers of the XIX and early XX century investigated the distribution of nebulæ in order to understand their relation to the local “sidereal system”, the Milky Way. The question they were trying to answer was whether or not the nebulæ are external to our own galaxy. The answer came at the beginning of the XX century, mainly through the works of V.M. Slipher and E. Hubble (see, e.g., Smith424). The extragalactic nature of nebulæ being established, astronomers started to consider clus- ters of galaxies as physical systems. The issue of how clusters form attracted the attention of K. Lundmark287 as early as in 1927. Six years later, F. Zwicky512 first estimated the mass of a galaxy cluster, thus establishing the need for dark matter. The role of clusters as laboratories for studying the evolution of galaxies was also soon realized (notably with the collisional stripping theory of Spitzer & Baade430). In the 50’s the investigation of galaxy clusters started to cover all aspects, from the distri- bution and properties of galaxies in clusters, to the existence of sub- and super-clustering, from the origin and evolution of clusters, to their dynamical status, and the nature of dark matter (or “positive energy”, see e.g., Ambartsumian29). -
Monthly Newsletter of the Durban Centre - March 2018
Page 1 Monthly Newsletter of the Durban Centre - March 2018 Page 2 Table of Contents Chairman’s Chatter …...…………………….……….………..….…… 3 Andrew Gray …………………………………………...………………. 5 The Hyades Star Cluster …...………………………….…….……….. 6 At the Eye Piece …………………………………………….….…….... 9 The Cover Image - Antennae Nebula …….……………………….. 11 Galaxy - Part 2 ….………………………………..………………….... 13 Self-Taught Astronomer …………………………………..………… 21 The Month Ahead …..…………………...….…….……………..…… 24 Minutes of the Previous Meeting …………………………….……. 25 Public Viewing Roster …………………………….……….…..……. 26 Pre-loved Telescope Equipment …………………………...……… 28 ASSA Symposium 2018 ………………………...……….…......…… 29 Member Submissions Disclaimer: The views expressed in ‘nDaba are solely those of the writer and are not necessarily the views of the Durban Centre, nor the Editor. All images and content is the work of the respective copyright owner Page 3 Chairman’s Chatter By Mike Hadlow Dear Members, The third month of the year is upon us and already the viewing conditions have been more favourable over the last few nights. Let’s hope it continues and we have clear skies and good viewing for the next five or six months. Our February meeting was well attended, with our main speaker being Dr Matt Hilton from the Astrophysics and Cosmology Research Unit at UKZN who gave us an excellent presentation on gravity waves. We really have to be thankful to Dr Hilton from ACRU UKZN for giving us his time to give us presentations and hope that we can maintain our relationship with ACRU and that we can draw other speakers from his colleagues and other research students! Thanks must also go to Debbie Abel and Piet Strauss for their monthly presentations on NASA and the sky for the following month, respectively. -
Structure in Radio Galaxies
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Coma Cluster of Galaxies
Coma Cluster of Galaxies In 2006, Hubble Space Telescope aimed at a nearby collection of NATIONAL SCIENCE EDUCATION STA N D A R D S galaxies called the Coma Cluster. Using the HST images, astronomers • Content Standard in 9-12 Science as gained fascinating insights into the evolution of galaxies in dense Inquiry (Abilities necessary to do sci- galactic neighborhoods. In this activity, students will first learn the entific inquiry, Understanding about basics of galaxy classification and grouping, then use HST images to scientific inquiry) discover the “morphology-density effect” and make hypotheses about • Content Standard in 9-12 Earth and its causes. Space Science (Origin and evolution of the universe) MATERIALS & PRE PARATION • Each student needs a copy of the next 7 pages (not this page). You may InvIsIble Clu s t e r copy the pages out of this guide, but it is recommended that you go to If you aim a big telescope at the Coma mcdonaldobservatory.org/teachers/classroom and download the student Cluster, you’ll see galaxies galore worksheets. The galaxy images in the online worksheets are “negatives” — thousands of galaxies of all sizes of the real images, which provides better detail when printing. Supple- and shapes, from little puffballs to mental materials for this activity are also available on the website. big, fuzzy footballs. Even so, you won’t • Each student or student team will need a calculator and a magnifying see most of the cluster because it’s invis- glass (a linen tester works well). ible to human eyes. • Knowledge of percentages is needed before doing this activity. -
Optical Counterparts of ROSAT X-Ray Sources in Two Selected Fields at Low
Astronomy & Astrophysics manuscript no. sbg˙comsge˙ed c ESO 2018 October 16, 2018 Optical counterparts of ROSAT X-ray sources in two selected fields at low vs. high Galactic latitudes J. Greiner1, G.A. Richter2 1 Max-Planck-Institut f¨ur extraterrestrische Physik, 85740 Garching, Germany 2 Sternwarte Sonneberg, 96515 Sonneberg, Germany Received 14 October 2013 / Accepted 12 August 2014 ABSTRACT Context. The optical identification of large number of X-ray sources such as those from the ROSAT All-Sky Survey is challenging with conventional spectroscopic follow-up observations. Aims. We investigate two ROSAT All-Sky Survey fields of size 10◦× 10◦ each, one at galactic latitude b = 83◦ (26 Com), the other at b = –5◦ (γ Sge), in order to optically identify the majority of sources. Methods. We used optical variability, among other more standard methods, as a means of identifying a large number of ROSAT All- Sky Survey sources. All objects fainter than about 12 mag and brighter than about 17 mag, in or near the error circle of the ROSAT positions, were tested for optical variability on hundreds of archival plates of the Sonneberg field patrol. Results. The present paper contains probable optical identifications of altogether 256 of the 370 ROSAT sources analysed. In partic- ular, we found 126 AGN (some of them may be misclassified CVs), 17 likely clusters of galaxies, 16 eruptive double stars (mostly CVs), 43 chromospherically active stars, 65 stars brighter than about 13 mag, 7 UV Cet stars, 3 semiregular resp. slow irregular variable stars of late spectral type, 2 DA white dwarfs, 1 Am star, 1 supernova remnant and 1 planetary nebula. -
Biennial Report 2006 2007 Published in Spain by the Isaac Newton Group of Telescopes (ING) ISSN 1575–8966 Legal License: TF–1142 /99
I SAAC N EWTON G ROUP OF T ELESCOPES Biennial Report 2006 2007 Published in Spain by the Isaac Newton Group of Telescopes (ING) ISSN 1575–8966 Legal license: TF–1142 /99 Apartado de correos, 321 E-38700 Santa Cruz de La Palma; Canary Islands; Spain Tel: +34 922 425 400 Fax: +34 922 425 401 URL: http://www.ing.iac.es/ Editor and designer: Javier Méndez ([email protected]) Printing: Gráficas Sabater. Tel: +34 922 623 555 Front cover: The Milky Way from the site of the William Herschel Telescope. Credit: Nik Szymanek. Inset: Photograph of the WHT at sunset. Credit: Nik Szymanek. Other picture credits: Nik Szymanek (WHT, p. 4; INT, p. 4; JKT, p. 4; ING, p. 5); Jens Moser (WHT, back; INT, back); Nik Szymanek (JKT, back). The ING Biennial Report is available online at http://www.ing.iac.es/PR/AR/. ISAAC NEWTON GROUP OF TELESCOPES Biennial Report of the STFC-NWO-IAC ING Board 2006 – 2007 ISAAC NEWTON GROUP William Herschel Telescope Isaac Newton Telescope Jacobus Kapteyn Telescope 4 • ING BIENNIAL R EPORT 2006–2007 OF TELESCOPES The Isaac Newton Group of Telescopes (ING) consists of the 4.2- metre William Herschel Telescope (WHT), the 2.5-metre Isaac Newton Telescope (INT) and the 1.0-metre Jacobus Kapteyn Telescope (JKT). The ING is located 2350 metres above sea level at the Observatorio del Roque de los Muchachos (ORM) on the island of La Palma, Canary Islands, Spain. The WHT is the largest telescope of its kind in Western Europe. The construction, operation, and development of the ING telescopes are the result of a collaboration between the United Kingdom, The Netherlands and Spain. -
Astronomy 113 Laboratory Manual
UNIVERSITY OF WISCONSIN - MADISON Department of Astronomy Astronomy 113 Laboratory Manual Fall 2011 Professor: Snezana Stanimirovic 4514 Sterling Hall [email protected] TA: Natalie Gosnell 6283B Chamberlin Hall [email protected] 1 2 Contents Introduction 1 Celestial Rhythms: An Introduction to the Sky 2 The Moons of Jupiter 3 Telescopes 4 The Distances to the Stars 5 The Sun 6 Spectral Classification 7 The Universe circa 1900 8 The Expansion of the Universe 3 ASTRONOMY 113 Laboratory Introduction Astronomy 113 is a hands-on tour of the visible universe through computer simulated and experimental exploration. During the 14 lab sessions, we will encounter objects located in our own solar system, stars filling the Milky Way, and objects located much further away in the far reaches of space. Astronomy is an observational science, as opposed to most of the rest of physics, which is experimental in nature. Astronomers cannot create a star in the lab and study it, walk around it, change it, or explode it. Astronomers can only observe the sky as it is, and from their observations deduce models of the universe and its contents. They cannot ever repeat the same experiment twice with exactly the same parameters and conditions. Remember this as the universe is laid out before you in Astronomy 113 – the story always begins with only points of light in the sky. From this perspective, our understanding of the universe is truly one of the greatest intellectual challenges and achievements of mankind. The exploration of the universe is also a lot of fun, an experience that is largely missed sitting in a lecture hall or doing homework. -
Tvsnews 05 01.Indd
2005 PRIMEFOCUS Tri-Valley Stargazers January January Meeting A Distributed Global Observing Network and the Mystery of Extrasolar Planet TrES-1b Ron Bissinger Affordable off-the- Meeting Info: shelf CCD digital cameras and medium aperture computer controlled telescopes have allowed an What increasing number of amateur astronomers to blur the line between amateur The Mystery of Extrasolar and professional astronomers. Amateur astronomers now frequently collaborate Planet TrES-1b with their professional colleagues on cutting-edge research endeavors. Who A current example of such an amateur/professional collaboration is the search Ron Bissinger for extrasolar planets. The American Association of Variable Star Observers (AAVSO) and the Transitsearch.org team have partnered to conduct world- When wide observing campaigns of stars that have, or may have, planetary systems. January 21, 2005 The 2003 discovery of a transiting extrasolar planet designated TrES-1b Conversation 7:00 p.m. prompted many amateur astronomers around the world to capture the light- Lecture 7:30 p.m. curve as the planet eclipsed, or transited, the parent star. Where Several amateur astronomers noted that the TrES-1b transit lightcurves did Unitarian Universalist not follow the classic, sharp-cornered “dips” of other transiting extrasolar Church in Livermore planets. These observations lead to an extensive and continuing analysis of the 1893 N. Vasco Road TrES-1b lightcurve to determine whether they indicate the presence of a struc- ture around the planet or its parent star. Whether or not any structure is ultimately confirmed around TrES-1b, the work exem- Inside plifies the high precision observations that News & Notes 2 are now made by a global group of amateur and professional astronomers formally coor- Calendar of Events 3 dinated over the internet.