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Earth-Moon vs Earth-Sun Lagrangian Point system

  1. Dec 29, 2010 #1
    My question

    Does the Sun influence the stability of the Lagrangian points in the Earth-Moon system?

    Apparently the concept of Lagrangian points works both in the Earth-Moon system and the Earth-Sun system. However, In the Earth-Moon system the Sun, as a third body, has a big influence on the two body Earth-Moon system. In the Earth-Sun system there is no significant third body. Is there a difference in which the Lagrangian point concept works in the two systems?
  2. jcsd
  3. Dec 29, 2010 #2
    Don't forget that the difference between Spring and Neap tides is mostly due to the Solar tide...

    IIRC, the 'classic' Earth/Moon Lagrange points are unstable due to perturbation by the Sun, but a slow 'orbit' around those points lets space telescopes etc hold position long enough to be useful...

    IIRC, the Sun/Earth system's leading and trailing 'Trojan' Lagrange points are rather more stable, but they're stirred by eg Venus...
  4. Dec 31, 2010 #3


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    Here's an article you might find interesting. I've tried simulating objects in the Earth/Moon L4 and L5 points and could only get them to complete a few orbits before becoming unstable. But this article describes simulations where John E. Chambers and Jack J. Lissauer were able to find stable orbits. Mr. Chambers was kind enough to send me the initial conditions of these objects, and indeed they lasted indefinately in my simulations too.

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