Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Discovery of a cool brown dwarf

Abstract

BROWN dwarfs are starlike objects with masses less than 0.08 times that of the Sun, which are unable to sustain hydrogen fusion in their interiors1–4. They are very hard to detect, as most of the energy of gravitational contraction is radiated away within 108 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 successful5,6. But there are only modest observable differences between young brown dwarfs and very lowmass stars, making it difficult to identify the former without appealing to sophisticated models7. 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 onetenth the luminosity of the least luminous hydro-gen-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.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Similar content being viewed by others

References

  1. Kumar, S. S. Astrophys. J. 137, 1121–1126 (1963).

    Article  ADS  Google Scholar 

  2. Tartar, J. C. in Astrophysics of Brown Dwarfs (eds Kafatos, M. C., Harrington, R. S. & Maran, S. P.) 121–138 (Cambridge Univ. Press, 1986).

    Google Scholar 

  3. Stevenson, D. J. A. Rev. Astr. Astrophys. 29, 163–193 (1991).

    Article  ADS  CAS  Google Scholar 

  4. Burrows, A. & Liebert, J. Rev. mod. Phys. 65, 301–336 (1993).

    Article  ADS  Google Scholar 

  5. Basri, G., Marcy, G. W. & Graham, J. R. Astrophys. J. (in the press).

  6. Rebolo, R., Zapatero Osorio, M. R. & Martin, E. L. Nature 377, 129–131 (1995).

    Article  ADS  CAS  Google Scholar 

  7. Magazzù A., Martin, E. L. & Rebolo, R. Astrophys. J. 404, L17–L20 (1993).

    Article  ADS  Google Scholar 

  8. Nakajima, T., Durrance, S. T., Golimowski, D. A. & Kulkarni, S. R. Astrophys. J. 428, 797–804 (1994).

    Article  ADS  Google Scholar 

  9. Leggett, S. K. Astrophys. J. Suppl. Ser. 82, 351–394 (1992).

    Article  ADS  Google Scholar 

  10. Hawley, S. L. in The Bottom of the Main Sequence—and Beyond (ed. Tinney, C. G.) 224–227 (Springer, Berlin, 1995).

    Book  Google Scholar 

  11. Pallavicini, R. Astr. Astrophys. Rev. 1, 177–207 (1989).

    Article  ADS  Google Scholar 

  12. Gliese, W. & Jahreiss, H. Preliminary Version of the Third Catalog of Nearby Stars (1991).

  13. Reid, I. N., Hawley, S. L. & Mateo, M. Mon. Not. R. astr. Soc. 272, 828–842 (1995).

    ADS  Google Scholar 

  14. Golimowski, D. A., Clampin, M., Durrance, S. T. & Barkhouser, R. H. Appl. Opt. 31, 4405–4416 (1992).

    Article  ADS  CAS  Google Scholar 

  15. Hirschfeld, A. & Sinnott, R. W. Sky Catalog 2000.0 Vol. 2 (Cambridge Univ. Press, Sky Publishing, Cambridge, 1995).

    Google Scholar 

  16. Tsuji, T., Ohnaka, K. & Aoki, W. in The Bottom of the Main Sequence—and Beyond (ed. Tinney, C. G.) 45–49 (Springer, Berlin. 1995).

    Book  Google Scholar 

  17. Henry, T. J. & McCarthy, D. W. Astr. J. 106, 773–789 (1993).

    Article  ADS  Google Scholar 

  18. Zuckerman, B. & Becklin, E. E. Astrophys. J. 386, 260–264 (1992).

    Article  ADS  Google Scholar 

  19. Tinney, C. G., Mould, J. R. & Reid, I. N. Astr. J. 105, 1045–1059 (1993).

    Article  ADS  CAS  Google Scholar 

  20. Allard, F. & Hauschildt, H. P. in The Bottom of the Main Sequence—and Beyond (ed. Tinney, C. G.) 32–40 (Springer, Berlin, 1995).

    Book  Google Scholar 

  21. Oppenheimer, B. R., Kulkarni, S. R., Matthews, K. & Nakajima, T. Science (in the press).

  22. Jones, H. R. A., Longmore, A. J., Jameson, R. F. & Mountain, C. M. Mon. Not. R. astr. Soc. 267, 413–423 (1994).

    Article  ADS  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

Nakajima, T., Oppenheimer, B., Kulkarni, S. et al. Discovery of a cool brown dwarf. Nature 378, 463–465 (1995). https://doi.org/10.1038/378463a0

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/378463a0

This article is cited by

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing