Re: In the Shadow of the Moon



Except that in that book the Earth sized body is a moon of the Jupiter
sized planet, not a Trojan.


And the 4th moon of Yarvin, in _Star Wars_.

But having an Earth form and orbit a Jupiter may not ever happen. There's some analysis of Jupiter, Saturn and Uranus and computer simulations that were done to show that the max total mass of a Jupiter's moon system is about 1/10000 of the planet's mass. Neptune's system seems to be too oddball to use for this, as Triton may be half of a captured Kuiper belt binary object. The other object running off with the extra orbital energy to let Trition settle in orbit around Neptune.
Anyway, you may need a really big Jupiter, like 30 times our Jupiter's mass, to get enough mass limit to have an Earth. But our Earth may be bigger than it needed to be, to have life happen.
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Relevant Pages

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