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Binary Stars and Their Planets

  1. Jun 12, 2009 #1
    I have a question regarding binary or multiple star systems and their [hypothetical] orbiting planets. I am curious if it is common (or even possible) for one or more of the orbiting planets to constantly switch the star they are orbiting, as in a figure eight shape. Can the stars "trade the planet" back and forth, as if juggling the planet? If so, are there any notable examples of this happening? I really don't know much about how this all works, I start my first year physics course this fall in school.

    I hope the question makes sense, if not, ask me and I will try and clarify some.
  2. jcsd
  3. Jun 12, 2009 #2


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    Only if the planet(s) would cross the Lagrange point between the stars. Usually however, planets are much closer to one of the stars.

    There are a few binaries known to have planets, e.g., Gliese 777 and Gamma Cephei (γ Cephei)

    Some astronomers think there is a chance that Alpha Centauri could have planets

    Thebault, P., Marzazi, F., Scholl, H.. "Planet formation in the habitable zone of alpha centauri B". Monthly Notices of the Royal Astronomical Society.

    But there is an issue of stability of planets in orbit around binary systems.
    M. Barbieri, F. Marzari, H. Scholl (2002). "Formation of terrestrial planets in close binary systems: The case of α Centauri A". Astronomy & Astrophysics 396: 219 – 224.

    See this paper with respect to the search for substellar (planetary) masses around stars
    Campbell, B., Walker, G. A. H., & Yang, S., A search for substellar companions to solar-type stars
    Last edited by a moderator: Apr 24, 2017
  4. Jun 12, 2009 #3
    Cool, thanks for the info.

    Is figuring out the orbit of these planets around these stars a matter of relativity equations or something?

    I have seen computer programs that model galaxy collisions, are there also programs that model planetary orbits, one that could potentially model this specific case? I don't know why this came to me, but the idea of a planet being juggled betwixt two or more stars just seems like a fascinating scenario. Am I alone in this?
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