UNIVERSE
SOLAR SYSTEM FORMATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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they are more dense
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they are the same size as the outer planets
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less material to make them ____ (the nebula had lots of gases)
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rock is more compact
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Detailed explanation-1: -The inner planets lost these very light gases. Their gravity was too low to keep them, and they floated away into space. The Sun and the outer planets had enough gravity to keep the hydrogen and helium.
Detailed explanation-2: -The inner planets were stripped bare down to their rocky cores and only formed a secondary atmosphere once radioactive heat and volcanic activity ignited their cores to force volatile gases to the surface.
Detailed explanation-3: -At larger masses, the planet’s ocean boils and the atmosphere becomes a dense mixture of steam and hydrogen and helium. When a planet reaches a few times the mass of Earth, the atmosphere will grow rapidly, faster than the solid part of the planet, eventually forming a gas giant planet like Jupiter.
Detailed explanation-4: -The planets nearest to the star tend to be rockier because the star’s wind blows away their gases and because they are made of heavier materials attracted by the star’s gravity.