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rough draft


Kepler-16: A Transiting Circumbinary Planet Doyle et. al. (2011)

Stability of S-type Orbits in Binaries Dvorak (2000)

The Fast and Fertile Universe and the Unstable Habitable Zone Gabor (2010)

Kepler 16: A System of Potential Interest to Astrobiologists Heath, Doyle (2011)

Long-Term Stability of Planets in Binary Systems Holman, Weigert (1999)

Modeling the Diversity of Outer Planetary Systems Levison, Lissauer, Duncan (1998)

Terrestrial Planet Formation in Binary Star Systems Quintana, Lissauer (2007)

Ally R

Recently, a planet (Kepler-16) was discovered orbiting a pair of low-mass stars (Doyle et. al. 2011). These questions aren't specific to this particular system, but they pertain to binary star systems in general. What effect does the orbital period of the binary star system have on the transit path of an orbiting planet? Is the planet's path consistent or is its shape irregular, depending on the movement of the two stars? What effect does this have on the habitable zone of the star system, or more specifically, does the habitable zone have an irregular shape? If different possible masses are considered for all objects, what can be determined about the interplay of motion within the system? What can be inferred about the formation and evolution of the system?

  • I'm intrigued, which is saying something because I hate physics generally. Can we (as in Bennington College, USA) actually take direct measurement of any of these "transit paths" you speak of? Or are these questions the type that would be addressed through computer simulations?--Wnakamura-koyam 03:41, 24 September 2011 (UTC)
    • Hey Weston, it would not be possible to take direct measurement here. The data regarding exoplanets is coming from the Kepler space telescope and HARPS, and I'm also pretty sure that what we can do here at Bennington College in Stickney is extremely limited in terms of direct observation, considering the state of our scope. I think that Rebecca Nakaba might know more about our limitations though... she's more experienced with the observatory than I am!
      • I'd be surprised if any current technology could get at these questions by direct observation? But what interests me is whether this sort of problem is soluble analytically -- or whether something like simulation is our only practical approach? Is this too much of a multi-body problem for Newton?Kwoods 01:06, 29 September 2011 (UTC)
    • check out binary stars in general to see how they interact with each other and the space around them; check out the similar body system of a star and a gas giant in the middle, with planets scattered around; check out who Doyle et al. cites; sounds like the wobble technique (observational or hypothetical depending on available data) would be the technique to explore; email nearby universities with observatories or professors doing binary star/planetary system research --Rnakaba 19:54, 30 September 2011 (UTC) (plus Anisha and Pratham)
    • This is an extremely interesting theoretical physics/mathematics question. What are the possible configurations? What is the stability of these configurations like? Because this is a theoretical physics question rather than an experimental one, I'll repeat my comment to Anisha above: Almost all of our discussion in class has been about experimental questions. But a theoretical physics question needs to be approached differently - it is more like a math question. You start with a question which is a point of curiosity. But then you need to learn more to try to refine exactly what it is you are asking. The question serves as a guide to the theoretical physics you need to learn, which will probably end up modifying your question, which will lead you to learning other physics, and other questions... With this sort of research question, you can't really know where it is going to end up until you start. And you can't set out the hypothesis from the beginning like you would with an experiment, because learning enough to make a good hypothesis is really part of the research. So maybe the next step here is to identify what you would need to know in order to refine the question. I think for your question, the key words are classical mechanics, the three-body problem, chaotic dynamics... Another thing you might look into is what sort of computer programs already exist for simulating the motion of a small number of bodies under gravitation. Having a simulation would allow you to make "experiments", and to make conjectures based on your experiments. -- Andrew
      • Yes, I think simulation is a good way to explore this. There appear to be quite a few ready-made solar system simulators out there; e.g. I do not know what they can do re binary star systems. (Although, if you make a giant planet big enough, there's no sharp line gravitationally speaking between a system of sun, a really big planet, and a smaller planet, and a system of two suns and a planet?). Kwoods 03:50, 11 November 2011 (UTC)
  • Don't know if this will help you, but it seems like a nice starting place? Orbits for Inner Planets of Binary Stars Their approach of 'guessing' a possible orbit might be a good way to narrow down your question-you could propose a path that a planet would take (elliptical, figure eight, etc.) and then examine that one possibility --Rnakaba 21:02, 18 November 2011 (UTC)

added miscellaneous

    • Also this: More things Specifically, the Math and Physics section --Rnakaba 21:07, 18 November 2011 (UTC)