Cap – Objektauswahl NGC
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Hubble Space Telescope Imaging of Brightest Cluster Galaxies1
Astronomical Journal, accepted for publication HUBBLE SPACE TELESCOPE IMAGING OF BRIGHTEST CLUSTER GALAXIES1 Seppo Laine2, Roeland P. van der Marel Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 Tod R. Lauer National Optical Astronomy Observatories, P.O. Box 26732, Tucson, AZ 85726 Marc Postman, Christopher P. O’Dea Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 and Frazer N. Owen National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801 ABSTRACT 1Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with proposal #8683. 2Present address: SIRTF Science Center, California Institute of Technology, 220-6, 1200 East California Boulevard, Pasadena, CA 91125 –2– We used the HST WFPC2 to obtain I-band images of the centers of 81 brightest cluster galaxies (BCGs), drawn from a volume-limited sample of nearby BCGs. The images show a rich variety of morphological features, including multiple or double nuclei, dust, stellar disks, point source nuclei, and central surface brightness depressions. High resolution surface brightness profiles could be inferred for 60 galaxies. Of those, 88% have well-resolved cores. The relationship between core size and galaxy luminosity for BCGs is indistinguishable from that of Faber et al. (1997, hereafter F97) for galaxies within the same luminosity range. However, the core sizes of the most luminous BCGs fall below the extrapolation of the F97 relationship r L1.15. -
ALABAMA University Libraries
THE UNIVERSITY OF ALABAMA University Libraries Seeing Galaxies through Thick and Thin. I. Optical Measures in Overlapping Galaxies Raymond E. White III – University of Alabama William C. Keel – University of Alabama Christopher J. Conselice – University of Chicago Deposited 09/18/2018 Citation of published version: White III, R., Keel, W., Conselice, C. (2000): Seeing Galaxies through Thick and Thin. I. Optical Measures in Overlapping Galaxies. The Astrophysical Journal, 542(2). DOI: https://doi.org/10.1086/317011 © 2000. The American Astronomical Society. All rights reserved. Printed in U.S.A. THE ASTROPHYSICAL JOURNAL, 542:761È778, 2000 October 20 ( 2000. The American Astronomical Society. All rights reserved. Printed in U.S.A. SEEING GALAXIES THROUGH THICK AND THIN. I. OPTICAL OPACITY MEASURES IN OVERLAPPING GALAXIES1 RAYMOND E. WHITE III2,3,4 NASA Goddard Space Flight Center, Laboratory for High Energy Astrophysics, Code 662, Greenbelt, MD 20771; and Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487-0324 WILLIAM C. KEEL2,3,4 Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487-0324 AND CHRISTOPHER J. CONSELICE3,5,6 Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 Received 2000 April 28; accepted 2000 May 24 ABSTRACT We describe the use of partially overlapping galaxies to provide direct measurements of the e†ective absorption in galaxy disks, independent of assumptions about internal disk structure. The non- overlapping parts of the galaxies and symmetry considerations are used to reconstruct, via di†erential photometry, how much background galaxy light is lost in passing through the foreground disks. Exten- sive catalog searches and follow-up imaging yield D15È25 nearby galaxy pairs suitable for varying degrees of our analysis; 11 of the best such examples are presented here. -
Seeing Galaxies Through Thick and Thin: I. Optical Opacity Measures In
Seeing Galaxies Through Thick and Thin: I. Optical Opacity Measures in Overlapping Galaxies RAYMOND E. WHITE III1,2,3 AND WILLIAM C. KEEL1,2,3 Department of Physics & Astronomy, University of Alabama, Tuscaloosa, AL 35487-0324 AND CHRISTOPHER J. CONSELICE2,4,5 Department of Astronomy & Astrophysics, University of Chicago arXiv:astro-ph/9608113v1 19 Aug 1996 1Visiting astronomer, Kitt Peak National Observatory, National Optical Astronomy Observatories, operated by AURA, Inc., under cooperative agreement with the National Science Foundation. 2Visiting astronomer, Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatories, likewise operated by AURA, Inc., under cooperative agreement with the National Science Foundation. 3Visiting astronomer, Lowell Observatory, Flagstaff, Arizona 4NSF REU summer student at University of Alabama 5present address: Department of Astronomy, University of Wisconsin –2– ABSTRACT We describe the use of partially overlapping galaxies to provide direct measurements of the effective absorption in galaxy disks, independent of assumptions about internal disk structure. The non-overlapping parts of the galaxies and symmetry considerations are used to reconstruct, via differential photometry, how much background galaxy light is lost in passing through the foreground disks. Extensive catalog searches yield ∼ 15 − 25 nearby galaxy pairs suitable for varying degrees of our analysis; ten of the best such examples are presented here. From these pairs, we find that interarm extinction is modest, B B declining from AB ∼ 1 magnitude at 0.3R25 to essentially zero by R25; the interarm dust has a scale length consistent with that of the disk starlight. In contrast, dust in spiral arms and resonance rings may be optically thick (AB > 2) at virtually any radius. -
Seeing Galaxies Through Thick and Thin. I. Optical Opacity Measures in Overlapping Galaxies1 Raymond E
THE ASTROPHYSICAL JOURNAL, 542:761È778, 2000 October 20 ( 2000. The American Astronomical Society. All rights reserved. Printed in U.S.A. SEEING GALAXIES THROUGH THICK AND THIN. I. OPTICAL OPACITY MEASURES IN OVERLAPPING GALAXIES1 RAYMOND E. WHITE III2,3,4 NASA Goddard Space Flight Center, Laboratory for High Energy Astrophysics, Code 662, Greenbelt, MD 20771; and Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487-0324 WILLIAM C. KEEL2,3,4 Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487-0324 AND CHRISTOPHER J. CONSELICE3,5,6 Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 Received 2000 April 28; accepted 2000 May 24 ABSTRACT We describe the use of partially overlapping galaxies to provide direct measurements of the e†ective absorption in galaxy disks, independent of assumptions about internal disk structure. The non- overlapping parts of the galaxies and symmetry considerations are used to reconstruct, via di†erential photometry, how much background galaxy light is lost in passing through the foreground disks. Exten- sive catalog searches and follow-up imaging yield D15È25 nearby galaxy pairs suitable for varying degrees of our analysis; 11 of the best such examples are presented here. From these pairs, we Ðnd that B B interarm extinction is modest, declining fromAB D 1 mag at 0.3R25 to essentially zero byR25 ; the inter- arm dust has a scale length consistent with that of the disk starlight. In contrast, dust in spiral arms and resonance rings may be optically thick(AB [ 2) at virtually any radius. Some disks have Ñatter extinc- tion curves than the Galaxy, withAB/AI B 1.6; this is probably the signature of clumpy dust distribu- tions. -
NGC New General Catalogue
NGC New General Catalogue CONSTELLATION: Andromeda............................................................................................................ 4 CONSTELLATION: Antlia..................................................................................................................... 6 CONSTELLATION: Apus ...................................................................................................................... 6 CONSTELLATION: Aquarius................................................................................................................ 7 CONSTELLATION: Aquila.................................................................................................................... 8 CONSTELLATION: Ara......................................................................................................................... 9 CONSTELLATION: Aries...................................................................................................................... 9 CONSTELLATION: Auriga ................................................................................................................. 10 CONSTELLATION: Boötes ................................................................................................................. 11 CONSTELLATION: Caelum ................................................................................................................ 14 CONSTELLATION: Camelopardalis ................................................................................................... 14 CONSTELLATION: -
NSSDC Data Listing
https://ntrs.nasa.gov/search.jsp?R=19950010026 2020-06-16T08:52:20+00:00Z NSSDC/WDC-A-R&S 94-09 NSSDC Data Listing Prepared by Richard Horowitz and Joseph H. King October 1994 National Space Science Data Center (NSSDC)/ World Data Center-A for Rockets and Satellites (WI)C-A-R&S) National Aeronautics and Space Administration Goddard Space Flight Center Greenbelt, Maryland 20771 CONTENTS 1.0 INTRODUCTION ................................................................................ 1 2.0 ELECTRONICALLY ACCESSIBLE DATA ............................................. 1 2.1 NDADS Data .................................................................................. 2 2.2 ANONYMOUS Account Data ............................................................... 4 2.3 NODIS Data ................................................................................... 5 3.0 DATA AVAILABLE ON CD-ROM ......................................................... 5 4.0 COMPREHENSIVE LISTINGS ............................................................ 7 4.1 Satellite Data Listings ......................................................................... 7 4.2 Astronomical Data Center Catalog Listings ................................................ 7 4.3 Other Data Available From NSSDC ........................................................ 7 5.1) ORDERING DATA FROM NSSDC ........................................................ 7 6.1} SUBMITTING DATA TO NSSDC ......................................................... 8 7.1} ACKNOWLEDGMENTS .....................................................................