why is the planet round ?

Answer 1

Lets combine and simplify some of these answers.

Gravity is what pulled things together to form planets. Gravity pulls equally in all directions, so a fairly uniform globe was formed. As the form grew larger, the more uniform the globe appeared.

Spinning does not form a globe. Spinning actually causes a globe to flatten out. If the globe spun fast enough, and the material were fluid enough, the globe would become a plate. If you have ever watched a glass blower make plates, you know what I'm describing.

Since our planent is made up of rocky slabs, floating on a molten core, the earth's spin does create a slighly flattened globe. The distortion is so minor, no one can actually see it. It took very accurate measurements with extremely sensitive instruments to detect this.

Answer 2

Because in any large collection of matter in space, gravity in effect pulls from the center of mass of all the matter, and tends to mold that matter into a sphere.

If a body is small enough, the material (rock) can be strong enough to resist being pulled into the spherical shape. This is the case of asteroids, which are too small to pull the material into a sphere. After a certain limit, though, gravity overcomes any significant bulges, peaks, etc.

Nothing is perfect, of course: you can still have relatively small features (like mountains and valleys) that make the body less than a perfect sphere.

Not only does spinning have nothing to do with the spherical shape, but it actually tends to make a planet bulge outward at its equator, making it a little more ellipsoidal.

Answer 3

The Natural shape of things in the universe is a sphere. Gravitational pull makes it so. It is the most efficient shape. Think of it. From the center of the sphere, to any point on the surface of the sphere - will always have the same distance.
hence when the molten rocks starts cooling off, it will try to get that shape. Water, in zero gravity will be a sphere.

The earth is not particularly a perfect sphere because of some scientific theories that the moon is originally a part of the earth.

your answer - Gravity.

Answer 4

when the planets were first formed they were molten state. Then they colded .
It is kinda like melting metal droping it is water. The material that you find when cooled will be round just a Natural thing I guess.

Answer 5

Gravity causes matter to coalesce, as matter falls in, it encounters resistance in the form of nuclear repulsion (i.e., stuff being compressed together), the state of equilibrium is a sphere, which also BTW is a shape that has the best volume:suface area.

Answer 6

the planet is not round it is more of a sphere shape be cause the moon is distorting it's shape by gravity

Answer 7

Gravity forces the matter on the planet to clump together.

Answer 8

are planet isn't round its more of an oval and it makes the force of gravity a more cmplicated thing

Answer 9

Well it spins. The spinning helps keep it in ball form and being a ball helps keep it spinning. Cubes don't spin very well, could you just imagine, a cubical Earth? Rachels answer is good too.

Answer 10

Because GOD made it that way. Some people might say if it's square or flat we'll fall off. But that's not true, It's because GOD knew what he was doing... Have a Blessed Day