Is it possible for planets to be able to spin, or rotate? on the same axis?

Question

you know how the planets spin aorund the sun, is it possible for another planet to be in the same line with another, like if earth had another planet next do them and it would be cool too because, the planets could be exactly the same ;x

Answer 1

none of the planets do.

but they could.

2 of saturn's moons do share an orbit.

http://en.wikipedia.org/wiki/Janus_(moon...

http://curious.astro.cornell.edu/questio...

Answer 2

this is basically what the earth and moon are doing now, but I'm sure there are many objects in the universe doing exactly what you are talking about, following each other in the same orbit.

Answer 3

yes, it is possible. Highly unlikely, but possible. A similar thing happens with stars as well. 2 get caught in eachothers orbit and spin around eachother. That's why you see stars"twinkle" in the night sky

Answer 4

I want to say yes and no... both for the same reasons.

Consider the asteroid belt. No one is sure whether it was a planet that broke up or one that never formed. But you could see if as a lot of little planets all sharing the same orbit. On the other hand, I see it as a hint of what might happen if the debris was spread out sooo evenly that nothing could form. So my guess is that what you are proposing is unlikely.

I think if you look at the complete solar system now, it seems like the space is there for 2 planets in the same orbit. But if you could go back to when the solar system was forming and it was all one big cloud or disc. I don't think two planets could form at opposite positions in the same orbit.

See, part of what starts planets forming is zillions of separate particles and chunks of matter all moving at different speeds and directions.  Its the random collisions is conjunction with the whole systems path thru the galaxy that starts the whole thing rotating. For that process to create two identically sized planets in opposition to one another just seems impossible. There would have to be some tiny random bit that would have one moving slightly faster than the other and eventually they would have to collide.