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What's the minimum possible size of a spherical shaped rocky planet or satellite? Is it possible to occur a spherical shaped planet without having a molten core?

Qmechanic
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2 Answers2

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The minimum radius of a celestial body that allows gravity to transform the body into a globe is informally called the potato radius. Empirical evidence suggests it is about 200-300 km, depending on the composition of the body - the higher the proportion of rock to ice, the larger the potato radius.

gandalf61
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This may depend on the source of heat: the kinetic energy of in-falling material or radioactivity. It has to get hot enough to flow under the action of gravity.

R.W. Bird
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