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Brown dwarfs: the stars that failed

Nature volume 397, pages 37–40 (1999)Cite this article

Abstract

In recent years, new astronomical instruments have reversed three decades of fruitless searching for brown dwarfs, the failed stars that are too small to burn nuclear fuel. These discoveries have confirmed predictions about the importance of methane and dust in the atmospheres of brown dwarfs. But they also demonstrate that, contrary to expectation, brown dwarfs do not contribute significantly to our Galaxy's dark matter.

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Figure 1: Luminosity and temperature as a function of mass and age for stars and brown dwarfs6.
Figure 2: Figure 2 Sequence of optical spectra showing the effects of increasing temperature for the brown dwarfs Gliese 229B35, DENIS-P J1228 − 154731, Kelu-137 and the low-mass star VB1028.

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Acknowledgements

I thank J. Hawthorn, P. Butler and H. Sim for comments, and G. Chabrier, I. Baraffe, B. Openheimer&J. D. Kirkpatrick for material used in the figures.

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  1. The author is at the Anglo-Australian Observatory, PO Box 296, NSW 1710, Epping, Australia

    C. G. Tinney

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Tinney, C. Brown dwarfs: the stars that failed. Nature 397, 37–40 (1999). https://doi.org/10.1038/16195

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