Dwarfs Walking in a Row the filamentary Nature of the NGC 3109 Association
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FY08 Technical Papers by GSMTPO Staff
AURA/NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation July 23, 2008 Revised as Complete and Submitted December 23, 2008 NGC 660, ~13 Mpc from the Earth, is a peculiar, polar ring galaxy that resulted from two galaxies colliding. It consists of a nearly edge-on disk and a strongly warped outer disk. Image Credit: T.A. Rector/University of Alaska, Anchorage NATIONAL OPTICAL ASTRONOMY OBSERVATORY NOAO ANNUAL REPORT FY 2008 Submitted to the National Science Foundation December 23, 2008 TABLE OF CONTENTS EXECUTIVE SUMMARY ............................................................................................................................. 1 1 SCIENTIFIC ACTIVITIES AND FINDINGS ..................................................................................... 2 1.1 Cerro Tololo Inter-American Observatory...................................................................................... 2 The Once and Future Supernova η Carinae...................................................................................................... 2 A Stellar Merger and a Missing White Dwarf.................................................................................................. 3 Imaging the COSMOS...................................................................................................................................... 3 The Hubble Constant from a Gravitational Lens.............................................................................................. 4 A New Dwarf Nova in the Period Gap............................................................................................................ -
ASTR 503 – Galactic Astronomy Spring 2015 COURSE SYLLABUS
ASTR 503 – Galactic Astronomy Spring 2015 COURSE SYLLABUS WHO I AM Instructor: Dr. Kurtis A. Williams Office Location: Science 145 Office Phone: 903-886-5516 Office Fax: 903-886-5480 Office Hours: TBA University Email Address: [email protected] Course Location and Time: Science 122, TR 11:00-12:15 WHAT THIS COURSE IS ABOUT Course Description: Observations of galaxies provide much of the key evidence supporting the current paradigms of cosmology, from the Big Bang through formation of large-scale structure and the evolution of stellar environments over cosmological history. In this course, we will explore the phenomenology of galaxies, primarily through observational support of underlying astrophysical theory. Student Learning Outcomes: 1. You will calculate properties of galaxies and stellar systems given quantitative observations, and vice-versa. 2. You will be able to categorize galactic systems and their components. 3. You will be able to interpret observations of galaxies within a framework of galactic and stellar evolution. 4. You will prepare written and oral summaries of both current and fundamental peer- reviewed articles on galactic astronomy for your peers. WHAT YOU ABSOLUTELY NEED Materials – Textbooks, Software and Additional Reading: Required: • Galactic Astronomy, Binney & Merrifield 1998 (Princeton University Press: Princeton) • Access to a desktop or laptop computer on which you can install software, read PDF files, compile code, and access the internet. Recommended: • Allen’s Astrophysical Quantities, 4th Edition, Arthur Cox, 2000 (Springer) Course Prerequisites: Advanced undergraduate classical dynamics (equivalent of Phys 411) or Phys 511. HOW THE COURSE WILL WORK Instructional Methods / Activities / Assessments Assigned Readings There is far too much material in the text for us to cover every single topic in class. -
Curriculum Vitae Avishay Gal-Yam
January 27, 2017 Curriculum Vitae Avishay Gal-Yam Personal Name: Avishay Gal-Yam Current address: Department of Particle Physics and Astrophysics, Weizmann Institute of Science, 76100 Rehovot, Israel. Telephones: home: 972-8-9464749, work: 972-8-9342063, Fax: 972-8-9344477 e-mail: [email protected] Born: March 15, 1970, Israel Family status: Married + 3 Citizenship: Israeli Education 1997-2003: Ph.D., School of Physics and Astronomy, Tel-Aviv University, Israel. Advisor: Prof. Dan Maoz 1994-1996: B.Sc., Magna Cum Laude, in Physics and Mathematics, Tel-Aviv University, Israel. (1989-1993: Military service.) Positions 2013- : Head, Physics Core Facilities Unit, Weizmann Institute of Science, Israel. 2012- : Associate Professor, Weizmann Institute of Science, Israel. 2008- : Head, Kraar Observatory Program, Weizmann Institute of Science, Israel. 2007- : Visiting Associate, California Institute of Technology. 2007-2012: Senior Scientist, Weizmann Institute of Science, Israel. 2006-2007: Postdoctoral Scholar, California Institute of Technology. 2003-2006: Hubble Postdoctoral Fellow, California Institute of Technology. 1996-2003: Physics and Mathematics Research and Teaching Assistant, Tel Aviv University. Honors and Awards 2012: Kimmel Award for Innovative Investigation. 2010: Krill Prize for Excellence in Scientific Research. 2010: Isreali Physical Society (IPS) Prize for a Young Physicist (shared with E. Nakar). 2010: German Federal Ministry of Education and Research (BMBF) ARCHES Prize. 2010: Levinson Physics Prize. 2008: The Peter and Patricia Gruber Award. 2007: European Union IRG Fellow. 2006: “Citt`adi Cefal`u"Prize. 2003: Hubble Fellow. 2002: Tel Aviv U. School of Physics and Astronomy award for outstanding achievements. 2000: Colton Fellow. 2000: Tel Aviv U. School of Physics and Astronomy research and teaching excellence award. -
PHYS 1302 Intro to Stellar & Galactic Astronomy
PHYS 1302: Introduction to Stellar and Galactic Astronomy University of Houston-Downtown Course Prefix, Number, and Title: PHYS 1302: Introduction to Stellar and Galactic Astronomy Credits/Lecture/Lab Hours: 3/2/2 Foundational Component Area: Life and Physical Sciences Prerequisites: Credit or enrollment in MATH 1301 or MATH 1310 Co-requisites: None Course Description: An integrated lecture/laboratory course for non-science majors. This course surveys stellar and galactic systems, the evolution and properties of stars, galaxies, clusters of galaxies, the properties of interstellar matter, cosmology and the effort to find extraterrestrial life. Competing theories that address recent discoveries are discussed. The role of technology in space sciences, the spin-offs and implications of such are presented. Visual observations and laboratory exercises illustrating various techniques in astronomy are integrated into the course. Recent results obtained by NASA and other agencies are introduced. Up to three evening observing sessions are required for this course, one of which will take place off-campus at George Observatory at Brazos Bend State Park. TCCNS Number: N/A Demonstration of Core Objectives within the Course: Assigned Core Learning Outcome Instructional strategy or content Method by which students’ Objective Students will be able to: used to achieve the outcome mastery of this outcome will be evaluated Critical Thinking Utilize scientific Star Property Correlations – They will be instructed to processes to identify students will form and test prioritize these properties in Empirical & questions pertaining to hypotheses to explain the terms of their relevance in Quantitative natural phenomena. correlation between a number of deciding between competing Reasoning properties seen in stars. -
Galactic Astronomy with AO: Nearby Star Clusters and Moving Groups
Galactic astronomy with AO: Nearby star clusters and moving groups T. J. Davidgea aDominion Astrophysical Observatory, Victoria, BC Canada ABSTRACT Observations of Galactic star clusters and objects in nearby moving groups recorded with Adaptive Optics (AO) systems on Gemini South are discussed. These include observations of open and globular clusters with the GeMS system, and high Strehl L observations of the moving group member Sirius obtained with NICI. The latter data 2 fail to reveal a brown dwarf companion with a mass ≥ 0.02M in an 18 × 18 arcsec area around Sirius A. Potential future directions for AO studies of nearby star clusters and groups with systems on large telescopes are also presented. Keywords: Adaptive optics, Open clusters: individual (Haffner 16, NGC 3105), Globular Clusters: individual (NGC 1851), stars: individual (Sirius) 1. STAR CLUSTERS AND THE GALAXY Deep surveys of star-forming regions have revealed that stars do not form in isolation, but instead form in clusters or loose groups (e.g. Ref. 25). This is a somewhat surprising result given that most stars in the Galaxy and nearby galaxies are not seen to be in obvious clusters (e.g. Ref. 31). This apparent contradiction can be reconciled if clusters tend to be short-lived. In fact, the pace of cluster destruction has been measured to be roughly an order of magnitude per decade in age (Ref. 17), indicating that the vast majority of clusters have lifespans that are only a modest fraction of the dynamical crossing-time of the Galactic disk. Clusters likely disperse in response to sudden changes in mass driven by supernovae and stellar winds (e.g. -
A Basic Requirement for Studying the Heavens Is Determining Where In
Abasic requirement for studying the heavens is determining where in the sky things are. To specify sky positions, astronomers have developed several coordinate systems. Each uses a coordinate grid projected on to the celestial sphere, in analogy to the geographic coordinate system used on the surface of the Earth. The coordinate systems differ only in their choice of the fundamental plane, which divides the sky into two equal hemispheres along a great circle (the fundamental plane of the geographic system is the Earth's equator) . Each coordinate system is named for its choice of fundamental plane. The equatorial coordinate system is probably the most widely used celestial coordinate system. It is also the one most closely related to the geographic coordinate system, because they use the same fun damental plane and the same poles. The projection of the Earth's equator onto the celestial sphere is called the celestial equator. Similarly, projecting the geographic poles on to the celest ial sphere defines the north and south celestial poles. However, there is an important difference between the equatorial and geographic coordinate systems: the geographic system is fixed to the Earth; it rotates as the Earth does . The equatorial system is fixed to the stars, so it appears to rotate across the sky with the stars, but of course it's really the Earth rotating under the fixed sky. The latitudinal (latitude-like) angle of the equatorial system is called declination (Dec for short) . It measures the angle of an object above or below the celestial equator. The longitud inal angle is called the right ascension (RA for short). -
Galaxies: Outstanding Problems and Instrumental Prospects for the Coming Decade (A Review)* T (Cosmology/History of Astronomy/Quasars/Space) JEREMIAH P
Proc. Natl. Acad. Sci. USA Vol. 74, No. 5, pp. 1767-1774, May 1977 Astronomy Galaxies: Outstanding problems and instrumental prospects for the coming decade (A Review)* t (cosmology/history of astronomy/quasars/space) JEREMIAH P. OSTRIKER Princeton University Observatory, Peyton Hall, Princeton, New Jersey 08540 Contributed by Jeremiah P. Ostriker, February 3, 1977 ABSTRACT After a review of the discovery of external It is more than a little astonishing that in the early part of this galaxies and the early classification of these enormous aggre- century it was the prevailing scientific view that man lived in gates of stars into visually recognizable types, a new classifi- a universe centered about himself; by 1920 the sun's newly cation scheme is suggested based on a measurable physical quantity, the luminosity of the spheroidal component. It is ar- discovered, slightly off-center position was still controversial. gued that the new one-parameter scheme may correlate well The discovery was, ironically, due to Shapley. both with existing descriptive labels and with underlying A little background to this debate may be useful. The Island physical reality. Universe hypothesis was not new, having been proposed 170 Two particular problems in extragalactic research are isolated years previously by the English astronomer, Thomas Wright as currently most fundamental. (i) A significant fraction of the (2), and developed with remarkably prescience by Emmanuel energy emitted by active galaxies (approximately 1% of all galaxies) is emitted by very small central regions largely in parts Kant, who wrote (see refs. 10 and 23 in ref. 3) in 1755 (in a of the spectrum (microwave, infrared, ultraviolet and x-ray translation from Edwin Hubble). -
Stsci Newsletter: 2011 Volume 028 Issue 02
National Aeronautics and Space Administration Interacting Galaxies UGC 1810 and UGC 1813 Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA) 2011 VOL 28 ISSUE 02 NEWSLETTER Space Telescope Science Institute We received a total of 1,007 proposals, after accounting for duplications Hubble Cycle 19 and withdrawals. Review process Proposal Selection Members of the international astronomical community review Hubble propos- als. Grouped in panels organized by science category, each panel has one or more “mirror” panels to enable transfer of proposals in order to avoid conflicts. In Cycle 19, the panels were divided into the categories of Planets, Stars, Stellar Rachel Somerville, [email protected], Claus Leitherer, [email protected], & Brett Populations and Interstellar Medium (ISM), Galaxies, Active Galactic Nuclei and Blacker, [email protected] the Inter-Galactic Medium (AGN/IGM), and Cosmology, for a total of 14 panels. One of these panels reviewed Regular Guest Observer, Archival, Theory, and Chronology SNAP proposals. The panel chairs also serve as members of the Time Allocation Committee hen the Cycle 19 Call for Proposals was released in December 2010, (TAC), which reviews Large and Archival Legacy proposals. In addition, there Hubble had already seen a full cycle of operation with the newly are three at-large TAC members, whose broad expertise allows them to review installed and repaired instruments calibrated and characterized. W proposals as needed, and to advise panels if the panelists feel they do not have The Advanced Camera for Surveys (ACS), Cosmic Origins Spectrograph (COS), the expertise to review a certain proposal. Fine Guidance Sensor (FGS), Space Telescope Imaging Spectrograph (STIS), and The process of selecting the panelists begins with the selection of the TAC Chair, Wide Field Camera 3 (WFC3) were all close to nominal operation and were avail- about six months prior to the proposal deadline. -
Observational Cosmology - 30H Course 218.163.109.230 Et Al
Observational cosmology - 30h course 218.163.109.230 et al. (2004–2014) PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Thu, 31 Oct 2013 03:42:03 UTC Contents Articles Observational cosmology 1 Observations: expansion, nucleosynthesis, CMB 5 Redshift 5 Hubble's law 19 Metric expansion of space 29 Big Bang nucleosynthesis 41 Cosmic microwave background 47 Hot big bang model 58 Friedmann equations 58 Friedmann–Lemaître–Robertson–Walker metric 62 Distance measures (cosmology) 68 Observations: up to 10 Gpc/h 71 Observable universe 71 Structure formation 82 Galaxy formation and evolution 88 Quasar 93 Active galactic nucleus 99 Galaxy filament 106 Phenomenological model: LambdaCDM + MOND 111 Lambda-CDM model 111 Inflation (cosmology) 116 Modified Newtonian dynamics 129 Towards a physical model 137 Shape of the universe 137 Inhomogeneous cosmology 143 Back-reaction 144 References Article Sources and Contributors 145 Image Sources, Licenses and Contributors 148 Article Licenses License 150 Observational cosmology 1 Observational cosmology Observational cosmology is the study of the structure, the evolution and the origin of the universe through observation, using instruments such as telescopes and cosmic ray detectors. Early observations The science of physical cosmology as it is practiced today had its subject material defined in the years following the Shapley-Curtis debate when it was determined that the universe had a larger scale than the Milky Way galaxy. This was precipitated by observations that established the size and the dynamics of the cosmos that could be explained by Einstein's General Theory of Relativity. -
An Observer's Guide to the (Local Group) Dwarf Galaxies: Predictions for Their Own Dwarf Satellite Populations
An observer's guide to the (Local Group) dwarf galaxies: predictions for their own dwarf satellite populations The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. Citation Dooley, Gregory A. et al. “An Observer’s Guide to the (Local Group) Dwarf Galaxies: Predictions for Their Own Dwarf Satellite Populations.” Monthly Notices of the Royal Astronomical Society 471, 4 (August 2017): 4894–4909 © 2018 The Author(s) As Published http://dx.doi.org/10.1093/MNRAS/STX1900 Publisher Oxford University Press (OUP) Version Author's final manuscript Citable link https://hdl.handle.net/1721.1/121369 Terms of Use Creative Commons Attribution-Noncommercial-Share Alike Detailed Terms http://creativecommons.org/licenses/by-nc-sa/4.0/ MNRAS 000,1{21 (2017) Preprint 6 September 2017 Compiled using MNRAS LATEX style file v3.0 An observer's guide to the (Local Group) dwarf galaxies: predictions for their own dwarf satellite populations Gregory A. Dooley1?, Annika H. G. Peter2;3, Tianyi Yang4, Beth Willman5, Brendan F. Griffen1 and Anna Frebel1, 1Department of Physics and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA 2CCAPP and Department of Physics, The Ohio State University, Columbus, OH 43210, USA 3Department of Astronomy, The Ohio State University, Columbus OH 43210, USA 4Institute of Optics, University of Rochester, Rochester, New York, 14627, USA 5Steward Observatory and LSST, 933 North Cherry Avenue, Tucson, AZ 85721, USA Accepted by MNRAS 2017 July 22. Received 2017 July 22; in original 2016 September 27 ABSTRACT A recent surge in the discovery of new ultrafaint dwarf satellites of the Milky Way has 3 6 inspired the idea of searching for faint satellites, 10 M < M∗ < 10 M , around less massive field galaxies in the Local Group. -
II. the Case of IC 4662 and ESO 245-G05?
A&A 369, 797–811 (2001) Astronomy DOI: 10.1051/0004-6361:20010179 & c ESO 2001 Astrophysics The chemical abundances in a sample of dwarf irregular galaxies II. The case of IC 4662 and ESO 245-G05? A. M. Hidalgo-G´amez1, J. Masegosa2, and K. Olofsson1 1 Astronomiska observatoriet, Box 515, 751 20 Uppsala, Sweden e-mail: [email protected] 2 Instituto de Astrof´ısica de Andaluc´ıa, CSIC, Apdo. 3004, 18080 Granada, Spain e-mail: [email protected] Received 29 November 2000 / Accepted 30 January 2001 Abstract. Optical spectra of H ii regions of two dwarf irregular galaxies are presented. The objects are IC 4662 and ESO 245-G05. Chemical abundances were derived in all the H ii regions where the forbidden oxygen line [OIII]λ4363 A˚ was detected. For spectra with the highest quality, a study of the spatial distribution of chemical elements in these objects were made. Generally, the chemical composition is largely constant within the H ii regions studied. Some differences are found but could be attributed varying physical properties, e.g. small scale fluctuations in the temperature of the region. A comparison of the chemical abundances between different H ii regions within the galaxies is made for IC 4662 and ESO 245-G05, where one of the H ii regions clearly shows deviating chemical abundances. Key words. galaxies: evolution – galaxies: irregular – galaxies: stellar content – interstellar medium: H ii regions: general – galaxies: individual: IC 4662, ESO 245-G05 1. Introduction A common characteristic uniting the three galaxies is the existence of several bright H ii regions which make In Paper I of this series (Hidalgo-G´amez et al. -
Imaging and Photometry of Nearby Dwarf Galaxies
A&A 433, 751–756 (2005) Astronomy DOI: 10.1051/0004-6361:20040263 & c ESO 2005 Astrophysics Imaging and photometry of nearby dwarf galaxies II. Southern dwarfs, L. N. Makarova1,2, I. D. Karachentsev1,E.K.Grebel3, D. Harbeck4,G.G.Korotkova1, and D. Geisler5 1 Special Astrophysical Observatory of the Russian Academy of Sciences, Nizhnij Arkhyz 369167, Karachaevo-Cherkessia, Russia e-mail: [email protected]; [email protected] 2 Isaac Newton Institute of Chile, SAO Branch 3 Astronomical Institute, University of Basel, Venusstrasse 7, 4102 Binningen, Switzerland e-mail: [email protected] 4 Department of Astronomy, University of Wisconsin, 475 North Charter Street, Madison, WI 53706-1582, USA e-mail: [email protected] 5 Departamento de Física, Grupo de Astronomía, Universidad de Concepción, Casilla 160-C, Concepción, Chile e-mail: [email protected] Received 13 February 2004 / Accepted 6 December 2004 Abstract. We carried out CCD photometry in the Johnson-Cousins B and R bands of 23 dwarf galaxies: SDIG, ESO 410-17, KK11, ESO 245-05, KKs3, KK27, KK38, KK40, IC 4662, KK244, KK246, KK247, KK248, KK249, KK253, KK255, KK256, KK257, KK258, KK259, UGCA 438, ESO 347-17, and UGCA 442. Both isolated galaxies and members of the Sculptor group and the NGC 1313 group were observed. The galaxy sample is characterized by a median distance of 9.3 Mpc, and median absolute magnitude of −14.8 mag. The central surface brightnesses are in the range from 22.2 to 24.4 mag arcsec−2 in B. Key words. galaxies: dwarf – galaxies: photometry – galaxies: irregular – galaxies: general – galaxies: evolution 1.