Willman 1
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Willman 1 | |
Observation data (J2000 epoch) | |
---|---|
Constellation | Ursa Major |
Right ascension | 10h 49m 22.3s[1] |
Declination | +51° 03′ 03.6″[1] |
Distance | 120 ± 20 kly (38 ± 7 kpc)[2] |
Type | extreme dSph or unusual globular cluster[1] |
Apparent magnitude (V) | 15.4 ± 0.4[a] |
Other designations | |
SDSS J1049+5103[1] | |
See also: Galaxy, List of galaxies |
Willman 1 or SDSS J1049+5103[2] is an extreme globular cluster or ultra low-mass dwarf galaxy[3] discovered by a team lead by Beth Willman of New York University, using Sloan Digital Sky Survey data. As of 2006, it is the third dimmest galaxy known, after Boo dSph and UMa dSph, 200 times dimmer than the next dimmest. The galaxy is a satellite of the Milky Way; ~120,000 light-years away. It has an absolute magnitude of -2.5.[2] The luminosity function varies between the center and the tails which suggest mass segregation similar to that found in Palomar 5.[2]
[edit] Notes
[edit] References
- NED (January 9, 2007), "Results for SDSS J1049+5103", NASA/IPAC Extragalactic Database (Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration), <http://nedwww.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=SDSS+J1049%2B5103>
- Willman, Beth; Michael R. Blanton & Andrew A. West et al. (2005), "A New Milky Way Companion: Unusual Globular Cluster or Extreme Dwarf Satellite?", The Astronomical Journal 129 (6): 2692-2700, <http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2005AAS...207.9101W>
- Willman, Beth; Morad Masjedi & David W. Hogg et al. (March 2006), "Willman 1 - A Galactic Satellite at 40 kpc With Multiple Stellar Tails", The Astronomical Journal subject to acceptance, <http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2006astro.ph..3486W>