Planet Shape?

Question

Whay are planets round? For some reason, everything we call a planet is on the round side. Not perfectly sperical, but close to it. We don't have planets that look like jagged rocks like large asteroids are.

Answer 1

In one word, the answer is gravity.

Gravity tries to pull everything as close together as possible. The more matter you have, the stronger the pull of gravity is. For planets, the pull of gravity is enough that eventually everything will tend to be reasonably round. Asteroids don't have enough mass to exert a strong enough gravity force to rearrange the structure, and hence they are not necessarily spherical.

Interesting note: Due to earth's rotation, centripetal force makes the equator bulge outwards (so Earth isn't actually that round)

Answer 2

Take a heavy peice of string or leather. Like a shoe string.

Hold it by one end and start spinning it in a small circle.

Once the rotation normalizes, the bottom will stay in pretty much the same place below your hand and the string will arc outward.

If you had a ball of really wet clay and spun it really fast, it would fling off anything that wasn't stuck well enough and the spinning motion would tend to pull it appart in all directions, so even what stayed would move to equalize pressure.

So part of the answer is centrifigual force.

Also gravity pulls equaly in all directions, so it's hold on the tops of mountians is weaker than it's hold on the ocean floor. This also means that, in formation, it will already be roughly spherical.

So, it starts off pretty round in the first place, then it's further rounded out by centrifigul force.

Answer 3

It;s the way things tend to collect under the influence of gravity. It winds up being the lowest energy state for things to coalesce. I can't imagine things collecting as a square or a pyramid. there would be stresses in the shape that would force it toward a spherical shape.

Answer 4

cause when they form, the heavy mass in the center pulls everything toward it, and everything tries to even out, which makes it spherical

Answer 5

gravity pulls everything to the core of that planet........idk i made that up

Answer 6

Ryan Faith Is this about you!??
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