Could two or more planets exist in a single orbital plane with out chance of collision? if not, why not?

Question

Is there some gravitational or astronomical law of that would prevent two planets from coexisting in a single orbital plane?

Answer 1

Yes. There are several points around an orbit that are considered more or less stable for a smaller mass. These are called LaGrange points.

http://www.physics.montana.edu/faculty/cornish/lagrange.html

There are six LaGrange points, but only two are truly stable, L4 and L5. The others require constant nudging. It has been theorized that any of these points would be a good place for a large-ish space station (something capable of supporting several thousand people). This inspired both the L-5 Society (which in the 1980's merged with the National Space Alliance to create the National Space Society) and the filk song "Home on LaGrange."
http://en.wikipedia.org/wiki/Home_on_Lagrange_(The_L5_Song)

In reality, the L4 and L5 points collect space debris that is left over from the formation of the Earth.

Answer 2

All the planets of the solar system are in fact, in a single plane (almost) but at different distances from sun. So, it is possible.

You can have different objects in the same orbit but distributed at different points along the orbit without colliding with each other. The velocity for a given orbit is same for all of them and so they will not collide.

So, I would say there is no such law. If you don't find such systems, it is probably because when the planet formed from the gas and dust clouds, it swept the smaller dust particles along the orbit and became bigger.

The asteroid belt is a good example that objects do exist in almost the same orbit without colliding with each other.

Answer 3

In theory, two bodies sharing the same orbit is possible. I doubt that it would form naturally, but neither would have much affect on each other. I would guess that the closer in mass each was (and in the same, exact orbit) would make it more stable, but when you're talking about the mass of the sun, the amount of mass as little as a planet would make very little difference.

Answer 4

I don't understand why Hibbo got 2 thumbs down, I think his answer was dead on.

If they are in the same orbit and one expects them not to collide EVER, they would have to be at least the same speed (on average) hence, probably the same mass.

Answer 5

it would all be based on the planets rate of speed around the star it circles.....obviously they would have to be identical speeds or evenually there would be a collision. Speed would be based on the size and mass of the particular planets as well as the distance from the star.

Answer 6

I'm no astrophysicist, but I would think the planets would have to be of the exact same mass and size, due to the gravitational pull around the sun.

Answer 7

would this other planet have green alien women that would want to have sex with me?