why are all the planets and moons shaped like balls?

Question

why are all the planets and moons shaped like balls? is it to do with gravity?

Answer 1

There are two effect:

1. gravity
2. statistics

The first is more important. While gravity is a weak force, planets get very big, and their gravitational force on accreting matter becomes large. The principle issue is that once a planet is large enough the forces due to gravity are larger than the forces holding matter together. For instance, on Earth the largest stable mountain at the surface is about twice the height of Everest, or about the height of Mauna Kea (its base is under the ocean). Rock is not strong enough to withstand gravity above this.

The spehrical shaped gravity causes is becuse gravity is a central force.

Small planetoids do not have such strong gravity and they are often not spherical, and asteroids can be any old lumpy shape.

The second factor is the accretion is a random or statistical process. This means matter gets added more or less in all directions (depending where a planet forms). And this helps planets to form at a mostly regular rate in all directions.

Answer 2

Simply put, the gravitational forces compact the matter uniformly and equally in all directions, creating a sphere or ball shape. The same reason why a bubble is spherical, the pressure is equal in all directions. Sometimes, the spinning of a planet will cause some of the mass to distribute to it's equator, making it a little oblong, but that is from centrifugal force, not gravity.

Answer 3

Gravity is the force that does the shaping.

But you have to have something that is plastic enough with a large enough gravitational field to create a sphere.

To be plastic the planet or moon has to be heated to the point of being liquid or near liquid.

If the planet is large eough it will also exhibit tectonic plates due to the slow motion "boiling" of the moltant materials beneith the crust. This will also help shape the planet.

Answer 4

It is a simple geometric law. A sphere is the shape that contains the largest volume for its surface area; therefore, fluid material accreting into a mass will naturally tend to take on a spherical shape.

This really has nothing to do with gravity. Simpler than that.

That is why raindrops are round, a glob of pizza dough dropped from an 11th story balcony will be round just before it hits you on the head, and a spoonful of pancake batter dropped into a pot of cold water will form a round glob. Reason why the yolk of an egg is spherical. Simple geometric law.

It is also related to why us guys' balls are spherical. Best ratio of volume to surface area.

Answer 5

Planets (...and also stars) form within immense drifting clouds of gas and dust. Every bit of gas and dust generates a tiny gravitational force. In relatively dense regions of the drifting cloud (...called a 'nebula') two or more bits of gas or dust may be close enough so that they're attracted to each other by their gravity. They clump together, which increases their overall gravity. This larger clump is surrounded by more bits and pieces which are drawn in from all directions. The original clump grows in size and produces more gravity, which in turn pulls in even more material from all directions. The result is a growing sphere.

Answer 6

via fact a sphere is the main power effective thank you to equipment the utmost quantity of quantity in the smallest floor section feasible, and thanks to gravity, which acts as though each and all of the mass of merchandise is on the middle of that mass. preserving a shape diverse than a sphere might recommend the bonding strengths of atoms might could be bigger to maintain that shape, and atoms and ions are around in shape besides.

Answer 7

They have enough gravity to mold the accretion into a ball..

Answer 8

yes u are right... if the cnteral foruce is what drives the mass to be intact, all the mass elements tries to be as close as possible to center! and that can be achieved by ball shape alone

Answer 9

well, personaly when i look up at the moon i dont see a pair of testicals, but then i dont have a man over me at the time, like maybe you would. so i wouldnt know your point-of-view from mine.

Answer 10

they're not they are elongated. its merely a misconception. and yes gravity does affect it.