jokergirl

2004-Feb-12, 04:17 PM

From http://map.gsfc.nasa.gov/m_mm/ob_techorbit1.html :

In the above contour plot we see that L4 and L5 correspond to hilltops and L1, L2 and L3 correspond to saddles (i.e. points where the potential is curving up in one direction and down in the other). This suggests that satellites placed at the Lagrange points will have a tendency to wander off (try sitting a marble on top of a watermelon or on top of a real saddle and you get the idea). A detailed analysis confirms our expectations for L1, L2 and L3, but not for L4 and L5. When a satellite parked at L4 or L5 starts to roll off the hill it picks up speed. At this point the Coriolis force comes into play - the same force that causes hurricanes to spin up on the earth - and sends the satellite into a stable orbit around the Lagrange point.

I would like an explanation as to how the coriolis force plays in that, i.e. what axis the orbit would be later, or what direction that force vector is.

Also, "roll off the hill" in which direction according to the rotational plane? After all, the effect of Coriolis force depends on direction too...

If you wanted to escape that force, what would be the nicest direction? Somebody claimed we didn't have the technology yet to escape the pulling force of L4/5, anybody knows more about that? What escape vector would be most promising according to those calculations?

There's another link on that, http://donar.physik.uni-bremen.de/nlp/publications/ChaosHTML/r14richter/node19.html , but I haven't been able to make anything out of it.

Oh yes, and I'm back. Missed me?

;)

In the above contour plot we see that L4 and L5 correspond to hilltops and L1, L2 and L3 correspond to saddles (i.e. points where the potential is curving up in one direction and down in the other). This suggests that satellites placed at the Lagrange points will have a tendency to wander off (try sitting a marble on top of a watermelon or on top of a real saddle and you get the idea). A detailed analysis confirms our expectations for L1, L2 and L3, but not for L4 and L5. When a satellite parked at L4 or L5 starts to roll off the hill it picks up speed. At this point the Coriolis force comes into play - the same force that causes hurricanes to spin up on the earth - and sends the satellite into a stable orbit around the Lagrange point.

I would like an explanation as to how the coriolis force plays in that, i.e. what axis the orbit would be later, or what direction that force vector is.

Also, "roll off the hill" in which direction according to the rotational plane? After all, the effect of Coriolis force depends on direction too...

If you wanted to escape that force, what would be the nicest direction? Somebody claimed we didn't have the technology yet to escape the pulling force of L4/5, anybody knows more about that? What escape vector would be most promising according to those calculations?

There's another link on that, http://donar.physik.uni-bremen.de/nlp/publications/ChaosHTML/r14richter/node19.html , but I haven't been able to make anything out of it.

Oh yes, and I'm back. Missed me?

;)