I understand gravity, but round and spin..

[pretendersfan]

Every planet we look at and have seen is round or near round, I understand the pull of gravity and the main star is the influence here, but you would think there would be some odd shapes of planets after the disintegration of stars. Also the orbit spins, are these constant through time, or is there a slow down or speed up???????

 

[Mirage]

Well, some planets and moons have big craters in them where something hit them at one point. As of right now everything seems to be working still as far as I can tell...

I believe since there is no friction in space for the most part that planets do not lose their orbit speed over time.

I wonder what would happen if a big asteroid graced the side of a planet though (hopefully not earth) just enough to give it a little extra spin speed. Our days would go by quicker and that would be really annoying. I think if an asteroid got that close we would attempt an Armageddon type mission to deter the asteroid. You never know if that is realistic though. It might not always be possible, if ever.

 

[Doc]

but you would think there would be some odd shapes of planets after the disintegration of stars. Also the orbit spins, are these constant through time, or is there a slow down or speed up?????

A planet can be an "odd" shape up until it reaches a certain size, then it being to collapse on itself form it's own gravity and is forced into a sphere/spherical shape.

Orbit and spin are caused by gravity, also. To be more specific, the sun's gravity. So, in theory, the gravity keeping them spinning is actually static and should the sun's gravity ever change, then the orbits, which could possibly lead to the rotation of the planet changing (speeding up/slowing down/nothing at all).

The closer to the sun, the faster it moves. The same goes for it's inverse. If there was a way to change how close/far the planet was from the Earth, then it would slow down/speed up to correct the change in distance from the sun's equator.

 

[Bunny_roses]

=Our days would go by quicker and that would be really annoying.

okey Andrew this made me laugh :lol: I mean really that's putting it mildly don't you think? I just had to comment because that cracked me up.

 

[Mirage]

Haha. Ok so there would be other things too but hey, I can keep it simple if I want can't I?

 

[Doc]

Quantum physics is fun!

 

[Hi_Im_Tim]

I might be mistaken, but i believe that the bigger the planets are, the greater the gravitational pull they exert, the more round they become, because the gravity is pulling them into a sphere.

 

[Doc]

You're exactly right, according to the current theories. Of course, any large body is going to be shaped into a spherical shape from gravity, even the smallest particles are rounded eventually.