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Discovery of a cool brown dwarf

Nakajima, T. and Oppenheimer, B. R. and Kulkarni, S. R. and Golimowski, D. A. and Matthews, K. and Durrance, S. T. (1995) Discovery of a cool brown dwarf. Nature, 378 (6556). pp. 463-465. ISSN 0028-0836. doi:10.1038/378463a0.

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Brown dwarfs are star-like objects with masses less than 0.08 times that of the Sun, which are unable to sustain hydrogen fusion in their interiors. They are very hard to detect, as most of the energy of gravitational contraction is radiated away within ~10^8 yr, leaving only a very low residual luminosity. Accordingly, almost all searches for brown dwarfs have been directed towards clusters of young stars—a strategy that has recently proved successful. But there are only modest observable differences between young brown dwarfs and very low-mass stars, making it difficult to identify the former without appealing to sophisticated models. Older brown dwarfs should have a more distinctive appearance, and if they are companions to nearby stars, their luminosity can be determined unambiguously. Here we report the discovery of a probable companion to the nearby star G1229, with no more than one-tenth the luminosity of the least luminous hydrogen-burning star. We conclude that the companion, G1229B, is a brown dwarf with a temperature of less than 1,200 K, and a mass ~20–50 times that of Jupiter.

Item Type:Article
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URLURL TypeDescription
Oppenheimer, B. R.0000-0001-7130-7681
Kulkarni, S. R.0000-0001-5390-8563
Additional Information:© 1995 Nature Publishing Group. Received 25 September; accepted 13 November 1995. We thank P. Goldreich, E. S. Phinney, I. N. Reid and M. van Kerkwijk for discussions. Some of the observations were conducted at the Palomar 60-inch telescope. which is jointly owned by the California Institute of Technology and the Carnegie Institution of Washington. At Caltech, this research was initiated from a seed grant from the Flintridge Foundation. S.R.K. is deeply indebted to the Foundation. The construction of the AOC was funded by the Seaver Institute. S.T.D. is grateful for their generous support. Our current activities are supported by the Packard Foundation, the US NSF and NASA. Infrared astronomy at Palomar is supported by the US NSF. B.R.O. is supported by an NSF graduate Fellowship. D.A.G. and S.T.D. thank the Center for Astrophysical Sciences at JHU for its support of this work.
Group:UNSPECIFIED, Division of Geological and Planetary Sciences
Funding AgencyGrant Number
Flintridge FoundationUNSPECIFIED
Seaver InstituteUNSPECIFIED
David and Lucile Packard FoundationUNSPECIFIED
NSF Graduate Research FellowshipUNSPECIFIED
JHU Center for Astrophysical SciencesUNSPECIFIED
Issue or Number:6556
Record Number:CaltechAUTHORS:20130419-090045769
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Official Citation:Discovery of a cool brown dwarf 463 T. Nakajima, B. R. Oppenheimer, S. R. Kulkarni, D. A. Golimowski, K. Matthews & S. T. Durrance doi:10.1038/378463a0
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:38031
Deposited By: Ruth Sustaita
Deposited On:19 Apr 2013 21:03
Last Modified:09 Nov 2021 23:33

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