Why are planets shaped like a sphere? Why not as a triangle or a square? Does the shape similiriaty between planets prove that they came from the same source and underwent same changes in the past?
2006-12-20 00:21:27 · 10 answers · asked by Neo 1 in Science & Mathematics ➔ Astronomy & Space
God didnt create anything, I asked for scientific answers, not blind religious answers. And btw, it says the planets are flat in the Bible rofl.
2006-12-20 00:32:46 · update #1
Planets are shaped like a sphere because gravity forces them to. Also, planets are not perfectly spherical but are a little bulging on the sides and long on the top and bottom.
2006-12-20 00:24:30 · answer #1 · answered by Trapped in a Box 6 · 1⤊ 0⤋
The shape of small objects (like people and houses and mountains and small asteroids) are determined by their mechanical properties. You can take a rock and cut it into a particular shape and it will pretty much stay that way.
The larger the object, though, the stronger its gravitational field. Imagine that you want to build a really tall building. You have to make sure it has a really strong foundation, or the foundation will be crushed by the weight of the building and the building will fall. If there was anything really big sticking up on a planet or a star, gravity would pull it down.
If a planet was like a cube, the corners of the cube would be higher than the rest of the planet. Since planets and stars are so big, you cannot build a "foundation" strong enough to hold up those corners! Anything you built it out of would be too weak to hold them up. Gravity would eventually pull them down.
Even solid rock will flow like a liquid, although very slowly, if it is pulled by a very strong gravitational force for a very long time. Corners on a cubical planet or star would eventually just squish down.
Since gravity pulls toward the center of the planet or star, everything gets pulled down into a sphere. However, planets and stars are not really perfect spheres. They spin, so they bulge out a little around the equator.
2006-12-20 02:32:11 · answer #2 · answered by Tim C 4 · 0⤊ 0⤋
Throw some water on the ground. It will form a flat puddle. Why? Because gravity pulls it down.
On the scale of a planet or star, the gravity is in the center. So everything flows (like a liquid to the centre). The ground we stand on is a like a liquid. Australia is a very flat place because all the mountains have over billions of years flowed down to being flat.
In fact the eart is so smooth, if it is reduced to the size of a billiard ball it would be smoother.
Also, most planets spin, so they bulg on the equater as the forces generated by the spinning cause the center conteract the forces of gravity.
2006-12-20 00:38:03 · answer #3 · answered by flingebunt 7 · 0⤊ 0⤋
While not perfect spheres the reason they are in that general shape is because any object with mass has gravity. This makes all the mass pull to the center which tends to even out the highs and lows to a point. I would also imagine that the spinning motion of the planets also would wear at any high spots which would encourage a round shape. Kind of like a rock in a stream or river. The edges get worn down due to materials around them.
2006-12-20 00:28:01 · answer #4 · answered by bourne3141592654 2 · 1⤊ 0⤋
a mass of liquid, in a zero gravity field, will arrange the mass in the most condensed form around it's center of gravity, and that shape is a perfect ball.
planets usually have a phase in the initial stages of their forming, when all or most of the mass of the planet is liquid or gas, and therefore it follows the same rule.
2006-12-20 00:29:54 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Its molecular attraction,the electrical charged particles pull themselves into a tightly pact ball or sphere.Its the shape of the cosmos.Look at high speed film of a water drop or any liquid.After it strikes and recoils it immediately forms a ball.That's how our moon was formed from the earth.
2006-12-22 15:57:41 · answer #6 · answered by Anonymous · 0⤊ 0⤋
the definition of the term PLANET says that
to be called a planet
1)it must be in orbit around a star.
2)has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a spherical (nearly round) shape.
2006-12-20 01:40:47 · answer #7 · answered by The TRUTH 2 · 0⤊ 0⤋
Because a sphere is the shape of nature.
That's why a pregnant belly, eyes, and asses are all shaped like spheres.
2006-12-20 00:28:14 · answer #8 · answered by Rachel 1 · 0⤊ 0⤋
they all have a core bt not like earths and are pulled by the sun hence the shape! round and around
2006-12-20 02:13:52 · answer #9 · answered by oysidius_torchwood 2 · 0⤊ 0⤋
because god created it to be like that
2006-12-20 00:24:12 · answer #10 · answered by mariefel q 3 · 0⤊ 0⤋