"While most extrasolar planets orbit too far from one another to feel each other’s gravity, researchers have found two systems with pairs of gas giant planets locked in an orbital embrace.
In one system—a planetary pair orbiting the massive, dying star HD 200964, located roughly 223 light-years from Earth—the intimate dance is closer and tighter than any previously seen.
“This new planet pair came in an unexpected package,” says John Johnson, an assistant professor of astronomy at the California Institute of Technology (Caltech).
“A planetary system with such closely spaced giant planets would be destroyed quickly if the planets weren’t doing such a well synchronized dance,” adds Eric Ford of the University of Florida in Gainsville. “This makes it a real puzzle how the planets could have found their rhythm.”More here:
http://www.futurity.org/science-technology/alien-planets-dance-around-dying-star/It would be really awesome if these orbits remain in their current settings for a long time, in the simulation I did shows that they do a great approach at some point in the orbit:

I believe that these orbits can not have little more than a few thousand years since the planets when encounter at the point where their orbits are closer (MOD - Minimum orbit intersection distance -
http://en.wikipedia.org/wiki / Minimum_orbit_intersection_distance) certainly pronouncedly affected the orbit of each other (I will go further simulation forward until this meeting) leading even to ejections or collisions of planets.
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