Questions tagged [brown-dwarfs]

Brown dwarfs are star-like objects that are too low in mass to fuse hydrogen-1 but still massive enough to fuse deuterium.

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Why does a drop in gravitational energy result in star contraction

Consider a gas cloud that is radiating away heat. From virial theorem we see that if the cloud radiates away heat and loses energy this will cause its gravitational energy to drop. Why does this mean ...
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Size of iron sphere with mass of our sun [closed]

What would be the diameter of a sphere of iron with the mass of our sun? Use standard density of metalic iron. I realize it would then collapse into a star in its own right and become much smaller as ...
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Super Heavy Brown Dwarf

As I understand black holes, they're considered "black" because the escape velocity is, or exceeds, the speed of light. Alternatively, the escaping light is redshifted infinitely. The Schwarzschild ...
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1answer
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Can the lithium test be applied to differentiate brown dwarfs from other substellar objects?

The lithium test is often used to differentiate brown dwarfs from low-mass M-type dwarfs (see e.g. Martin et al. (1994)), because brown dwarfs (at least the lower-mass ones) do not burn lithium, ...
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1answer
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Could the estimated stellar mass for the Milky Way galaxy include brown dwarfs?

Trying to find an estimate for the stellar mass of the MW galaxy, I found this paper and the estimated stellar mass is $~6.5 \times 10^{10} M_{\odot}$. I was also trying to understand the methods used ...
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According to the initial mass function, should there be more brown dwarfs than red dwarfs?

According to the IMF and the stellar mass distribution, stars become more abundant the less massive they are. And while objects must have a mass > 0.075 solar mass to become a star, brown dwarfs with ...
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“Cloud maps” of a nearby brown dwarf: what do they actually show?

This paper recently made headlines: A global cloud map of the nearest known brown dwarf. I. J. M. Crossfield et al. Nature 505, 654–656 (30 January 2014). In short, they claim they've been able to ...