[Space] How much does a Gas Giant heat it's moons?

[Kraydak]

Originally Posted by Anthony

Brown dwarfs are stars, not planets.

For reference, there are two competing dividing lines between brown dwarfs and (really, REALLY) big gas giant planets.

1) Deuterium burning. This has some observational consequences for some objects, but is otherwise really, really boring. It just measures mass.

2) Formation mechanism (direct gravitational collapse, like a star, or core-accretion building up a rocky core, like a planet). While more conceptually useful than definition (1), it doesn't make any observational predictions…