Hi Sawyer

Yours seems to be gaining favour as the right taxonomy.

"Planet" meant "wanderer" in the heavens, visible to the naked eye. None of the telescopic 'planets' was known to the ancients and it's as much a historical accident as any other that we call them 'wandering stars' too.

But physically there are so many differences that a blanket term is awfully limited. We could say any body big enough to be round and physically differentiated, and small enough not to have crossed the maximum radius and form a degenerate core?

Brown dwarfs would then be everything with a degenerate core and no Main Sequence fusion cycle - thus including all the BDs that have fused their deuterium and lithium.

Undifferentiated bodies would cover a pretty big range and exclude Ceres and Vesta, and ironically include Jupiter if it is convective all the way down.

Hmmm...

Adam