Further we dramatically underestimated the number of expo planets for decades. Quite reasonably we don’t put a lot of weight on stuff we can’t detect.
A brown dwarf orbiting a red dwarf would beg to differ.
https://simple.wikipedia.org/wiki/Brown_dwarf
While very young they generate heat from both deuterium fusion but that only lasts millions to tens of millions of years. Energy from radioactive decay and their slow contraction lasts for much longer.
When I think of the brown dwarf I am also reminded of the hypothesized black dwarf. This would be the stage after white dwarf. It's hypothesized because it takes longer for the white dwarf bodies to cool than exists presently in the history of the universe. It's only a handful of sentences and will largely repeat the previous paragraph but there's the wiki page for black dwarf.
https://simple.wikipedia.org/wiki/Black_dwarf
Very interesting stuff all around. Space is so fucking cool, y'all.
It might even be possible to have this combination weigh less than our sun