phoenixshade
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I've been following this discussion for a while, and just wanted to add a few points. First, I'm pretty confident that we can dismiss the idea of a massive body orbiting in a nearly perpendicular plane to the others. The reason I say this is because if this was the case, the chances that we'd have SIX planets in nearly exactly the same plane becomes vanishingly small. Try it: Add a M_{J} planet to the system at 0.8 AU with inclination 0° and let the system run for a few hundred millennia. The inclinations of the planets will seem almost random. The other point I wanted to address is the eccentricity of these orbits. I will have to follow up on this, but I believe that planets discovered by transit have an "assumed zero" until further observations based on some other method (i.e. NOT transits). The reason is because we only have ONE POINT (actually, it's a very short arc, but for practical purposes it can be considered a point) on the orbit where we can make observations. Even with repeated observation of the transits, we're still looking at the SAME POSITION in the orbit. Eccentricity can not be determined with only data from a single point. There are three variables we can measure based on the transit: (1) The PERIOD of the orbit (obviously, based on repeated regular intervals between transits), (2) the CROSSSECTIONAL AREA of the planet (based on how much the star's apparent magnitude decreases during the transit), and (3) the LENGTH OF TIME of the transit, which when combined with the period allows us to calculate the inclination, but ONLY if we assume a very small eccentricity and some diameter of the star based on mass and spectral class. In order to calculate the eccentricity, we'd either need data from (at least) one other point on the orbit, or accurate data on the planet's velocity (relative to the star) at the known point. Transits of planets can give us neither (eclipsing binary stars, on the other hand, readily give us a second data point), but redshift data can fill the velocity gap. Additional Note: While writing this, I was running the modified system as described above with an additional planet. It didn't even take 2000 years before the system was catastrophically disrupted, leaving only 11b, 11g, and the hypothetical "11h" after the collisions and ejections resolved.
