Could a planet have a figure 8 orbit?

[ihwip]

OK. I am betting that this would require some serious luck to develop but is it possible that a binary star system could have a planet orbitting in such a manner that it was traded imbetween the two stars when the two stars were closest together?

I guess one half of the planet's orbit would need to be the same length of time as a full orbit of either star. Or something like that. The stars would also have to be identical in size to avoid the planet lagging behind and missing the next pass.

My question is basically if this is even possible, not so much that it is probable to ever happen.

 

[ramparts]

I believe something like this is possible but as you can imagine, it's difficult to make one of these which is also stable. Others here should know more...

 

[crazyeddie]

My question is basically if this is even possible, not so much that it is probable to ever happen.

Yes, it is possible:

http://burtleburtle.net/bob/physics/eight.html

 

[Gravity_Ray]

cool graphic eddie, if the 3rd object is a planet then it must be one in a zillion to have a stable 3 body system with 2 stars and a planet that do a figure 8.

I am sure it will be a very interesting light show on the surface of the planet, but it dosent seem very life friendly though.

 

[ihwip]

Very cool. I am not sure if it answers my specific scenario though. I was thinking of a binary star system that has a minor object doing the figure 8s. This would mean that the two stars would have equal mass and then planet would have a mass approaching zero. Three body systems frighten and confuse me so I am not sure how to do the calculations myself. I know that a binary star system basically looks like a pair of elliptical orbits. What I want to know is if you could insert a planet into the system where it would swap stars at their closest pass. I don't think that website had an example for that.

 

[Gravity_Ray]

I think the post from Eddie shows a stable system. By stable I mean all 3 bodies continue to orbit each other. If you are talking about two big stars swaping a planet or planetoid from one to the other, I would think (but can not prove) that the tidal forces will probably crush the planet and make it a ring of debris.

 

[MeteorWayne]

Technically, no system with more than 2 bodies can ever be shown to be stable indefinately