We’ve talked a little bit about planetary migration and how it might happen. For some reason, a good chunk of distant solar systems feature hot Jupiter’s, large enough that they may have formed in the frost belt, orbiting crazy close to their primary star. Tidal deceleration, interaction and collision with other planets or smaller objects, detection bias? A new system worlds that could collide may offer clues:
(Wired Mag) — A rocky planet 1.5 times the size of Earth and a Neptune-like gas giant were spotted orbiting a star daringly close to each other.
The two-planet Kepler-36 system is the Kepler space telescope’s latest treasured find, reported today in the journal Science by researchers from the Harvard-Smithsonian Center for Astrophysics and the University of Washington. Passing less than five Earth-moon distances apart every 97 days, the planets are far closer together and more different in density than any two planets in our solar system.
Looking from the smaller planet’s surface (as depicted above), the gas giant would appear more than twice as big as the full Moon appears from Earth. The wrenching gravity between the planets would stretch and squeeze them, which might make the rocky one volcanic.
Kepler 36 is 1200 light years away toward the constellation Cygnus. The star is slightly larger and hotter than our sun and it’s estimated to be about 6 to 7 billion years old. The two planets orbit the star very close, around two weeks for their respective “years.”
It is extremely unlikely an ice giant formed well inside the equivalent orbit of Mercury or that this close arrangement between two planets would be stable for 6 billion years. Some thing is going on in this system and with these two planets that we do not understand. And if we figure it out, it could help explain how and why what should be frozen gas giants orbiting elegantly in the far, cold reaches seem to spiral in closer and faster to their star in so many exo solar system.