Brown Dwarfs

[Corkeyno2]

This may sound like a dumb question, but why do brown dwarfs glow if they do not have nuclear fusion? If anyone could tell me I would be very grateful.

Thanks,

Corkey

 

[Knight of Clear Skies]

They retain some heat from their formation and slowly cool over time. They mostly emit in the infrared spectrum. I'm not sure but they also probably generate heat from gravitational contraction.

[Corkeyno2]

9 minutes ago, Knight of Clear Skies said:

They retain some heat from their formation and slowly cool over time. They mostly emit in the infrared spectrum. I'm not sure but they also probably generate heat from gravitational contraction.

cheers

[andrew s]

5 hours ago, Corkeyno2 said:

They retain some heat from their formation and slowly cool over time.

Indeed almost all of the heat comes from the gravitational energy released as the material collapses to form the brown dwarf in the first place and then any subsequent contraction . Another source would be from the decay of radio active elements as in the center of the earth.

Regards Andrew