Why are all planets perfectly round i know they have been spinning for billions of years but ???????

Question

Why are all planets perfectly round i know they have been spinning for billions of years but ???????

Answer 1

The earth is actually an oblate spheroid, but that's incidental..

They are round as this is the most stable shape to complete a regular orbital path. Non-regular shaped objects will find it very difficult to maintain regular orbits of their stars and either eventually the orbit will decay, resulting in a crash with the star or the object will spin away from the star never to be seen again (as it were).

Answer 2

Gravity keeps them together, but they are far from perfectly round - only Venus is as close as possible to a round shape, because of it's very slow rotation.

Earths shape is called actually a geoid, though potato would not be far from the truth.

Jupiter for example is really oblate, because of it's high rotation speed.  

Answer 3

agglomeration theory and gravity

Answer 4

The answer to that is they are not perfectly round they are in fact all different sphere shapes, the Earth is slightly elongated at the equator and is not a perfect sphere.

Answer 5

guess what? it is not PERFECTLY round ya know. and it can't be. it's an oblate spheroid. no body's perfect..=]

Answer 6

It's all down to gravity. Gravity pulls the centre of planets inwards causing them to become spheres.

Answer 7

They are not perfectly round because the centrifugal force created when they spin makes planets flattened at the poles of thier axles. However, objects do have a tendency to become spherical as gravity pulls objects towards the lowest area of ground, equalising it's distance from the centre of mass.  

Answer 8

because GOD said so

Answer 9

Everyone's answered this question perfectly well. I just wanted to add that the sphere is the most common shape in nature from planets and stars to atoms. It's the most functional structural shape...

Answer 10

Planets are round because their gravitational field acts as though it originates from the center of the body and pulls everything toward it. With its large body and internal heating from radioactive elements, a planet behaves like a fluid, and over long periods of time succumbs to the gravitational pull from its center of gravity. The only way to get all the mass as close to planet's center of gravity as possible is to form a sphere. The technical name for this process is "isostatic adjustment."

A planet's defining physical characteristic is that it is large enough for the force of its own gravity to dominate over the electromagnetic forces binding its physical structure, leading to a state of hydrostatic equilibrium. This effectively means that all planets are spherical or spheroidal. Up to a certain size, an object can be irregular in shape, but beyond that point, which varies depending on the chemical makeup of the object, gravity begins to pull an object towards its own center of mass until the object collapses into a sphere.

The act of spinning would not create a spheroidal orb.

Answer 11

Planets aren't perfectly round, though they may appear to be. For example, the Earth is a bit oblong. Planets aren't round because they have been spinning for billions of years, they are round because of their own gravity becoming balanced with the pressure. The gravity is pushing all the matter towards the core, but the pressure is pushing everything out. When these two forces become balanced, the object has achieved "hydrostatic equilibrium" which causes the object to become spherical... but not perfectly spherical.

Answer 12

They aren't perfectly round, but the models you see usually are.

Earth, for example, is a bit flattened at the poles and has a slight bulge at the equator.

Answer 13

the earth is less than 10,000 years old. No proof says earth has been here 100 millions years, that hasnt been disproved....

Answer 14

Each planet's gravity pulls from the planet's center equally in every direction, and this results in a sphere. Smaller objects, like asteroids and comets, can be irregular shape because their gravity is not strong enough. But bigger objects, like planets and stars, were made spherical by their own gravity.