Two Planets Discovered Sharing the Same Orbit

Popular Science ^ | Friday, February 25, 2011 | Julie Beck

[mikrofon]

Thank you — they usually muck up science reporting in the guise of looking smart.

If it means the LARGER body is the one does the peculiar Figure-8 thing at the Lagrange point, I could see the reference to the sizes...

[TigersEye]

I didn’t read that the Lagrange points were 120 degrees in front of and behind the larger one. I read they were in front of and behind the smaller one.

Yes, that is what the text said. Draw a circle on a piece of paper. Draw points on the circle 120 degrees apart from each other. You should have three points all equidistant. No matter where you put the large body in relation to the smaller body it will be 120 from both Lagrange points.

[TigersEye]

OK, but the size of a Lagrange point is something entirely different than the question of whether an LP is 120 degrees in front of and behind the smaller body or the larger body.

[Lancey Howard]

Yes, that is what the text said. Draw a circle on a piece of paper. Draw points on the circle 120 degrees apart from each other. You should have three points all equidistant. No matter where you put the large body in relation to the smaller body it will be 120 from both Lagrange points.

I have one thing to say to that...

[Lancey Howard]

I think the problem with articles like this is the (natural) tendency of lay authors to try to simplify complicated scientific theory in order to make it accesible to the masses. An earlier post noted that the Lagrangian points that are most likely to be inhabited by a third body (ie., a larger planet) are actually 60 degrees (not 120) in front of and behind the smaller body.

[LonePalm]

Does this help?

The L4 & L5 are SIXTY DEGREES leading and trailing of the planet involved.

Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)

[TigersEye]

You got it! I’m glad because I had no idea how to proceed to give a clearer explanation. I was at the outer limit of my mental orbit. ;^)

[TigersEye]

No, not at all. What happened to 120 degree separations?

[airborne]

Cool link!

I got 2 planets in a crazy elliptical orbit around a third.

[LonePalm]

You can not have a 'larger' (more massive) body in the L4 or L5 points. If you did, than it would become the planet and the original planet would occupy the Lagrange point.

In fact, the cumulative mass at any of the Lagrange points can not be greater than a small fraction to the planet. You might get something the size of the earth into Jupiter's L4 or L5 but you couldn't get something the size of Saturn. The two masses would destroy each others orbit.

Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)

[LonePalm]

The article was WRONG.

Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)

[TigersEye]

The article was WRONG.

Finally, an answer to the question.

[hattend]

[TangoLimaSierra]

That is one cool toy.

[Beowulf9]

This is a great picture! Painting, whatever, it’s not real, right? Some sort of graphics?

[SunkenCiv]

It’s an artist’s conception, but I agree, it’s pretty cool.

[SunkenCiv]

http://www.freerepublic.com/focus/chat/1718935/posts