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TSP 2004 Telescope Observing Program
THE TEXAS STAR PARTY 2004 TELESCOPE OBSERVING CLUB BY JOHN WAGONER TEXAS ASTRONOMICAL SOCIETY OF DALLAS RULES AND REGULATIONS Welcome to the Texas Star Party's Telescope Observing Club. The purpose of this club is not to test your observing skills by throwing the toughest objects at you that are hard to see under any conditions, but to give you an opportunity to observe 25 showcase objects under the ideal conditions of these pristine West Texas skies, thus displaying them to their best advantage. This year we have planned a program called “Starlight, Starbright”. The rules are simple. Just observe the 25 objects listed. That's it. Any size telescope can be used. All observations must be made at the Texas Star Party to qualify. All objects are within range of small (6”) to medium sized (10”) telescopes, and are available for observation between 10:00PM and 3:00AM any time during the TSP. Each person completing this list will receive an official Texas Star Party Telescope Observing Club lapel pin. These pins are not sold at the TSP and can only be acquired by completing the program, so wear them proudly. To receive your pin, turn in your observations to John Wagoner - TSP Observing Chairman any time during the Texas Star Party. I will be at the outside door leading into the TSP Meeting Hall each day between 1:00 PM and 2:30 PM. If you finish the list the last night of TSP, or I am not available to give you your pin, just mail your observations to me at 1409 Sequoia Dr., Plano, Tx. -
Annual Report 2009-2010
ICRAR AnnuAl RepoRt 2009-2010 Annual Report 2009/10 Document ICRAR-DOC-0016 ICRAR Annual Report 2009/10 11 August 2010 FRONT COVER: Top Left: A group photo of some members of the ICRAR Board, ICRAR Executive and Professor Richard Schilizzi (Director SKA Program Development Office) at the launch of ICRAR, 1 September 2009 – photo Jurgen Lunsmann Top Right: The Murchison Wide-field Array 32 tile system on the Murchison Radio- astronomy Observatory June 2010 – photo Paul Bourke and Jonathan Knispel, WASP Middle Left: Three-dimensional supercomputer model of supernovae 1987a – image Toby Potter, ICRAR Middle: Year 10 students attending the “Out There” SKA event in March 2009 - photo Paul Ricketts, Centre for Learning Technology UWA Middle Right: Supercomputer simulation of hydrogen gas in the early Universe – image Dr Alan Duffy, ICRAR Bottom Left: Radio emission from the inner core of the galaxy Centaurus A as seen by the first disk of the ASKAP telescope coupled to a dish in New Zealand 5500 km away – image Prof Steven Tingay (ICRAR) / ICRAR, CSIRO and AUT Bottom Right: Stars and gas in the colliding galaxy NGC 922 – image Prof Gerhardt Meurer (ICRAR) and Dr Kenji Bekki (ICRAR) 2 ICRAR Annual Report 2009/10 11 August 2010 Table of Contents 1.0 Executive Summary ..............................................................................................5! 1.1 Major Developments and Highlights of 2009/10 ................................................5! 1.2 National and International Collaborations..........................................................6! -
Arxiv:1911.09125V2 [Astro-Ph.SR] 23 Jun 2020 Maccarone Et Al
Draft version June 25, 2020 Typeset using LATEX twocolumn style in AASTeX63 A Dynamical Survey of Stellar-Mass Black Holes in 50 Milky Way Globular Clusters Newlin C. Weatherford,1, 2 Sourav Chatterjee,3 Kyle Kremer,1, 2 Frederic A. Rasio,1, 2 1Department of Physics & Astronomy, Northwestern University, Evanston, IL 60208, USA 2Center for Interdisciplinary Exploration & Research in Astrophysics (CIERA), Northwestern University, Evanston, IL 60208, USA 3Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005, India ABSTRACT Recent numerical simulations of globular clusters (GCs) have shown that stellar-mass black holes (BHs) play a fundamental role in driving cluster evolution and shaping their present-day structure. Rapidly mass-segregating to the center of GCs, BHs act as a dynamical energy source via repeated super-elastic scattering, delaying onset of core collapse and limiting mass segregation for visible stars. While recent discoveries of BH candidates in Galactic and extragalactic GCs have further piqued inter- est in BH-mediated cluster dynamics, numerical models show that even if significant BH populations remain in today's GCs, they are not typically in directly detectable configurations. We demonstrated in Weatherford et al.(2018) that an anti-correlation between a suitable measure of mass segregation (∆) in observable stellar populations and the number of retained BHs in GC models can be applied to indirectly probe BH populations in real GCs. Here, we estimate the number and total mass of BHs in 50 Milky Way GCs from the ACS Globular Cluster Survey. For each GC, ∆ is measured between observed main sequence populations and fed into correlations between ∆ and BH retention found in our CMC Cluster Catalog's models. -
NGC 3125−1: the Most Extreme Wolf-Rayet Star Cluster Known in the Local Universe1
NGC 3125−1: The Most Extreme Wolf-Rayet Star Cluster Known in the Local Universe1 Rupali Chandar and Claus Leitherer Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218 [email protected] & [email protected] and Christy A. Tremonti Steward Observatory, 933 N. Cherry Ave., Tucson, AZ, 85721 [email protected] ABSTRACT We use Space Telescope Imaging Spectrograph long-slit ultraviolet spec- troscopy of local starburst galaxies to study the massive star content of a represen- tative sample of \super star" clusters, with a primary focus on their Wolf-Rayet (WR) content as measured from the He II λ1640 emission feature. The goals of this work are three-fold. First, we quantify the WR and O star content for selected massive young star clusters. These results are compared with similar estimates made from optical spectroscopy and available in the literature. We conclude that the He II λ4686 equivalent width is a poor diagnostic measure of the true WR content. Second, we present the strongest known He II λ1640 emis- sion feature in a local starburst galaxy. This feature is clearly of stellar origin in the massive cluster NGC 3125-1, as it is broadened (∼ 1000 km s−1). Strong N IV] λ1488 and N V λ1720 emission lines commonly found in the spectra of individual Wolf-Rayet stars of WN subtype are also observed in the spectrum of NGC 3125-1. Finally, we create empirical spectral templates to gain a basic understanding of the recently observed strong He II λ1640 feature seen in Lyman Break Galaxies (LBG) at redshifts z ∼ 3. -
The Large Scale Distribution of Radio Continuum in Ε and So Galaxies
THE LARGE SCALE DISTRIBUTION OF RADIO CONTINUUM IN Ε AND SO GALAXIES R.D. Ekers, Kapteyn Astronomical Institute, University of Groningen If we look at the radio properties of the nearby ellipticals we find a situation considerably different from that just described by van der Kruit for the spiral galaxies. For example NGC 5128 (Cen A), the nearest giant elliptical galaxy, is a thousand times more powerful a radio source than the brightest spiral galaxies and furthermore its radio emission comes from a multiple lobed radio structure which bears no resemblance to the optical light distribution (e.g. Ekers, 1975). The other radio emitting elliptical galaxies in our neighbourhood, NGC 1316 (Fornax A), IC 4296 (1333-33), have similar morphology. A question which then arises is whether at lower levels we can detect radio emission coming from the optical image of the elliptical galaxies and which may be more closely related to the kind of emission seen in the spiral galaxies. Since elliptical galaxies are less numerous than spiral galaxies we have to search out to the Virgo cluster to obtain a good sample. Some results from a Westerbork map of the central region of the Virgo cluster at 1.4 GHz (Kotanyi and Ekers, in preparation) is given in the Table. Radio Emission from Galaxies in the core of the Virgo Cluster Name Hubble m Flux density NGC Type Ρ (JO"29 W m-2 Hz-1) 4374 El 10.8 6200 3C 272.1 4388 Sc 12.2 140 4402 Sd 13.6 60 4406 E3 10.9 < 4 4425 SO 13.3 < 4 4435 SO 1 1.9 < 5 4438 S pec 12.0 150 This result is typical for spiral and elliptical galaxies and illustrates the different properties quite well. -
Mining SDSS in Search of Multiple Populations in Globular Clusters
A&A 525, A114 (2011) Astronomy DOI: 10.1051/0004-6361/201015662 & c ESO 2010 Astrophysics Mining SDSS in search of multiple populations in globular clusters C. Lardo1, M. Bellazzini2, E. Pancino2, E. Carretta2, A. Bragaglia2, and E. Dalessandro1 1 Department of Astronomy, University of Bologna, via Ranzani 1, 40127 Bologna, Italy e-mail: [email protected] 2 INAF - Osservatorio Astronomico di Bologna, via Ranzani 1, 40127 Bologna, Italy Received 31 August 2010 / Accepted 6 October 2010 ABSTRACT Several recent studies have reported the detection of an anomalous color spread along the red giant branch (RGB) of some globular clusters (GC) that appears only when color indices including a near ultraviolet band (such as Johnson U or Strömgren u) are con- sidered. This anomalous spread in color indexes such as U − B or cy has been shown to correlate with variations in the abundances of light elements such as C, N, O, Na, etc., which, in turn, are generally believed to be associated with subsequent star formation episodes that occurred in the earliest few 108 yr of the cluster’s life. Here we use publicly available u, g, r Sloan Digital Sky Survey photometry to search for anomalous u − g spreads in the RGBs of nine Galactic GCs. In seven of them (M 2, M 3, M 5, M 13, M 15, M 92 and M 53), we find evidence of a statistically significant spread in the u − g color, not seen in g − r and not accounted for by observational effects. In the case of M 5, we demonstrate that the observed u − g color spread correlates with the observed abundances of Na, the redder stars being richer in Na than the bluer ones. -
X-Ray Luminosities for a Magnitude-Limited Sample of Early-Type Galaxies from the ROSAT All-Sky Survey
Mon. Not. R. Astron. Soc. 302, 209±221 (1999) X-ray luminosities for a magnitude-limited sample of early-type galaxies from the ROSAT All-Sky Survey J. Beuing,1* S. DoÈbereiner,2 H. BoÈhringer2 and R. Bender1 1UniversitaÈts-Sternwarte MuÈnchen, Scheinerstrasse 1, D-81679 MuÈnchen, Germany 2Max-Planck-Institut fuÈr Extraterrestrische Physik, D-85740 Garching bei MuÈnchen, Germany Accepted 1998 August 3. Received 1998 June 1; in original form 1997 December 30 Downloaded from https://academic.oup.com/mnras/article/302/2/209/968033 by guest on 30 September 2021 ABSTRACT For a magnitude-limited optical sample (BT # 13:5 mag) of early-type galaxies, we have derived X-ray luminosities from the ROSATAll-Sky Survey. The results are 101 detections and 192 useful upper limits in the range from 1036 to 1044 erg s1. For most of the galaxies no X-ray data have been available until now. On the basis of this sample with its full sky coverage, we ®nd no galaxy with an unusually low ¯ux from discrete emitters. Below log LB < 9:2L( the X-ray emission is compatible with being entirely due to discrete sources. Above log LB < 11:2L( no galaxy with only discrete emission is found. We further con®rm earlier ®ndings that Lx is strongly correlated with LB. Over the entire data range the slope is found to be 2:23 60:12. We also ®nd a luminosity dependence of this correlation. Below 1 log Lx 40:5 erg s it is consistent with a slope of 1, as expected from discrete emission. -
SPIRIT Target Lists
JANUARY and FEBRUARY deep sky objects JANUARY FEBRUARY OBJECT RA (2000) DECL (2000) OBJECT RA (2000) DECL (2000) Category 1 (west of meridian) Category 1 (west of meridian) NGC 1532 04h 12m 04s -32° 52' 23" NGC 1792 05h 05m 14s -37° 58' 47" NGC 1566 04h 20m 00s -54° 56' 18" NGC 1532 04h 12m 04s -32° 52' 23" NGC 1546 04h 14m 37s -56° 03' 37" NGC 1672 04h 45m 43s -59° 14' 52" NGC 1313 03h 18m 16s -66° 29' 43" NGC 1313 03h 18m 15s -66° 29' 51" NGC 1365 03h 33m 37s -36° 08' 27" NGC 1566 04h 20m 01s -54° 56' 14" NGC 1097 02h 46m 19s -30° 16' 32" NGC 1546 04h 14m 37s -56° 03' 37" NGC 1232 03h 09m 45s -20° 34' 45" NGC 1433 03h 42m 01s -47° 13' 19" NGC 1068 02h 42m 40s -00° 00' 48" NGC 1792 05h 05m 14s -37° 58' 47" NGC 300 00h 54m 54s -37° 40' 57" NGC 2217 06h 21m 40s -27° 14' 03" Category 1 (east of meridian) Category 1 (east of meridian) NGC 1637 04h 41m 28s -02° 51' 28" NGC 2442 07h 36m 24s -69° 31' 50" NGC 1808 05h 07m 42s -37° 30' 48" NGC 2280 06h 44m 49s -27° 38' 20" NGC 1792 05h 05m 14s -37° 58' 47" NGC 2292 06h 47m 39s -26° 44' 47" NGC 1617 04h 31m 40s -54° 36' 07" NGC 2325 07h 02m 40s -28° 41' 52" NGC 1672 04h 45m 43s -59° 14' 52" NGC 3059 09h 50m 08s -73° 55' 17" NGC 1964 05h 33m 22s -21° 56' 43" NGC 2559 08h 17m 06s -27° 27' 25" NGC 2196 06h 12m 10s -21° 48' 22" NGC 2566 08h 18m 46s -25° 30' 02" NGC 2217 06h 21m 40s -27° 14' 03" NGC 2613 08h 33m 23s -22° 58' 22" NGC 2442 07h 36m 20s -69° 31' 29" Category 2 Category 2 M 42 05h 35m 17s -05° 23' 25" M 42 05h 35m 17s -05° 23' 25" NGC 2070 05h 38m 38s -69° 05' 39" NGC 2070 05h 38m 38s -69° -
Caldwell Catalogue - Wikipedia, the Free Encyclopedia
Caldwell catalogue - Wikipedia, the free encyclopedia Log in / create account Article Discussion Read Edit View history Caldwell catalogue From Wikipedia, the free encyclopedia Main page Contents The Caldwell Catalogue is an astronomical catalog of 109 bright star clusters, nebulae, and galaxies for observation by amateur astronomers. The list was compiled Featured content by Sir Patrick Caldwell-Moore, better known as Patrick Moore, as a complement to the Messier Catalogue. Current events The Messier Catalogue is used frequently by amateur astronomers as a list of interesting deep-sky objects for observations, but Moore noted that the list did not include Random article many of the sky's brightest deep-sky objects, including the Hyades, the Double Cluster (NGC 869 and NGC 884), and NGC 253. Moreover, Moore observed that the Donate to Wikipedia Messier Catalogue, which was compiled based on observations in the Northern Hemisphere, excluded bright deep-sky objects visible in the Southern Hemisphere such [1][2] Interaction as Omega Centauri, Centaurus A, the Jewel Box, and 47 Tucanae. He quickly compiled a list of 109 objects (to match the number of objects in the Messier [3] Help Catalogue) and published it in Sky & Telescope in December 1995. About Wikipedia Since its publication, the catalogue has grown in popularity and usage within the amateur astronomical community. Small compilation errors in the original 1995 version Community portal of the list have since been corrected. Unusually, Moore used one of his surnames to name the list, and the catalogue adopts "C" numbers to rename objects with more Recent changes common designations.[4] Contact Wikipedia As stated above, the list was compiled from objects already identified by professional astronomers and commonly observed by amateur astronomers. -
The Astrophysical Journal Supplement Series, 45:259-334
.259W The Astrophysical Journal Supplement Series, 45:259-334, 1981 February 45. © 1981. The American Astronomical Society. All rights reserved. Printed in U.S.A. ... 198lApJS A CATALOG OF RADIAL VELOCITIES IN GALACTIC GLOBULAR CLUSTERS1 R. F. Webbink Department of Astronomy, University of Illinois at Urbana-Champaign Received 1980 February 25; accepted 1980 July 9 ABSTRACT A catalog of all stellar and integrated radial velocities of galactic globular clusters published prior to 1980 is assembled here. Known systematic errors in the data are discussed, and data on 686 stars and 85 globular clusters are presented in the body of the catalog; an Appendix lists published radial velocities in 4 dwarf spheroidal satellites of the Galaxy. Weighted mean velocities for each of the 89 systems in the catalog and Appendix are calculated. Subject headings: clusters: globular— stars: catalogs I. INTRODUCTION data. No catalog of individual stellar and cluster veloci- Radial velocities of galactic globular clusters were ties exists as such. first obtained in the pioneering surveys by Slipher (1918, The present catalog is intended to fill the need for a 1919, 1922, 1924), at Lowell Observatory, and by San- comprehensive listing of all available globular cluster ford (1918, 1919a,6), at Mount Wilson, who together radial velocity data and to provide a systematic reassess- obtained velocities of 18 clusters. In the more than 60 ment of the cluster velocities on this basis. To the best of years since those studies, several other radial velocity the author’s knowledge, all data published prior to 1980 surveys have been published, of which the most exten- January 1 are included here. -
Optical Astronomy Observatories
National Optical Astronomy Observatories National Optical Astronomy Observatories Quarterly Report July - September 1989 TABLE OF CONTENTS I. INTRODUCTION j II. SCIENTIFIC HIGHLIGHTS 2 A. Ages of Globular Ousters 2 B. Disk Galaxies in Formation 2 C. Differential Rotation Observed in the Sun as a Star 3 D. Intensity Oscillations in the Far-Infrared 4 E. Supergranular Convection 4 F. Brown Dwarfs: A Detection of Stellar Objects of Subcritical Mass? 5 G. Cooling Flows in Clusters of Galaxies: Where Are All the Stars? 5 III. PERSONNEL 7 A. Visiting Scientists 7 B. New Appointees 7 C. Terminations 7 D. Change of Status ' g E. Summer Research Assistants 8 IV. INSTRUMENTATION, NEW PROJECTS, AND OBSERVATORY ACTIVITIES .... 9 A. Future Telescope Technology Program (FTT) 9 B. Global Oscillation Network Group (GONG) 9 C. Instrumentation Projects ]\ D. Observatory Activities 16 V. PROGRAM SUPPORT !9 A. Director's Office 19 B. Central Administrative Services 20 C. Central Computer Services 20 D. Central Facilities Operations 20 E. Engineering and Technical Services 21 F. Publications and Information Resources 21 Appendices Appendix A: Telescope Usage Statistics Appendix B: Observational Programs I. INTRODUCTION This quarterly report covers scientific highlights for the period of July - September 1989, as well as personnel changes for the period. These highlights emphasize concluded projects rather than work in progress. The report also discusses new technology for telescopes and instrumentation, GONG, instrumentation projects, and observatory activities. The Engineering and Technical Services division now submits reports for the instrumentation projects, with contributions from program scientists, if necessary. The Associate Directors for CTIO and NSO continue to provide the information of efforts at La Serena/Cerro Tololo and Sacramento Peak. -
108 Afocal Procedure, 105 Age of Globular Clusters, 25, 28–29 O
Index Index Achromats, 70, 73, 79 Apochromats (APO), 70, Averted vision Adhafera, 44 73, 79 technique, 96, 98, Adobe Photoshop Aquarius, 43, 99 112 (software), 108 Aquila, 10, 36, 45, 65 Afocal procedure, 105 Arches cluster, 23 B1620-26, 37 Age Archinal, Brent, 63, 64, Barkhatova (Bar) of globular clusters, 89, 195 catalogue, 196 25, 28–29 Arcturus, 43 Barlow lens, 78–79, 110 of open clusters, Aricebo radio telescope, Barnard’s Galaxy, 49 15–16 33 Basel (Bas) catalogue, 196 of star complexes, 41 Aries, 45 Bayer classification of stellar associations, Arp 2, 51 system, 93 39, 41–42 Arp catalogue, 197 Be16, 63 of the universe, 28 Arp-Madore (AM)-1, 33 Beehive Cluster, 13, 60, Aldebaran, 43 Arp-Madore (AM)-2, 148 Alessi, 22, 61 48, 65 Bergeron 1, 22 Alessi catalogue, 196 Arp-Madore (AM) Bergeron, J., 22 Algenubi, 44 catalogue, 197 Berkeley 11, 124f, 125 Algieba, 44 Asterisms, 43–45, Berkeley 17, 15 Algol (Demon Star), 65, 94 Berkeley 19, 130 21 Astronomy (magazine), Berkeley 29, 18 Alnilam, 5–6 89 Berkeley 42, 171–173 Alnitak, 5–6 Astronomy Now Berkeley (Be) catalogue, Alpha Centauri, 25 (magazine), 89 196 Alpha Orionis, 93 Astrophotography, 94, Beta Pictoris, 42 Alpha Persei, 40 101, 102–103 Beta Piscium, 44 Altair, 44 Astroplanner (software), Betelgeuse, 93 Alterf, 44 90 Big Bang, 5, 29 Altitude-Azimuth Astro-Snap (software), Big Dipper, 19, 43 (Alt-Az) mount, 107 Binary millisecond 75–76 AstroStack (software), pulsars, 30 Andromeda Galaxy, 36, 108 Binary stars, 8, 52 39, 41, 48, 52, 61 AstroVideo (software), in globular clusters, ANR 1947