(October 17, 2012 at 5:00 pm)Chuck Wrote: Also, the hypothetical distinction between small brown dwarves and big planets seems to have not received much support. ie planets grade into brown dwarves without any clear objective demarcation.Well, generally they're far too big and massive to be gas giants, and too small to be red dwarfs.
Typically, brown dwarfs are hot enough to fuse elements such lithium, but not hydrogen.