With what evidence? The dividing criteria between jovians and brown dwarfs is normally taken as the latter (a) being dense enough to undergo helium fusion (for a brief period) and (thereafter) convecting. I don't see much (surface) evidence of Jupiter convecting, and it's way below the gravity threshold for helium fusion; which is not to say it might not have been able to do other more esoteric forms of fusion, but if that ever happened, it was very briefly, and a very long time ago, and wouldn't have constituted more than a flash in the planet.
I've no idea. As I say, I don't know if anyone takes it at all seriously. But I've heard it, which is more than any other explanation for Jupiter not being a planet I've.
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Date: 2006-08-24 02:06 pm (UTC)(no subject)
Date: 2006-08-24 02:15 pm (UTC)