Eli5: In our solar system, why are all of the gas giants past the meteor belt? Is it just a coincidence? Do other solar systems have similar organizations, with some rocky planets, a meteor belt, then gas giant planets, or is ours unique?

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In: Planetary Science

Answer 1

There are no reasons gas giants cannot exist inside an asteroid belt, in fact there are asteroid belts beyond Neptune.

The reason however that our Solar system is probably quite typical are:

– Large gas planets cannot exist too close to the sun for too long. Due to the effects of tidal forces on the gas giant, a gas giant will slowly become tidal locked and then lose matter to the star’s gravitational pull and eventually be consumed by the star if it is too close.

– Similarly rocky planets like our own, if formed too close to a gas giant will likely be gravitationally captured by the gas giant and become a moon of that gas giant rather than a planet orbiting the central star.

Combining these two facts gives you that the planets closer to the star tend to be rocky, as solid planets are less impacted by the tidal effects than gaseous planets and rocky planets further away tend to end up being the moons of gas giants rather than planets of their own accord.