Alien solar systems with multiple planets appear to be common in our galaxy, but most of them are quite different than our own, a new study finds.
NASA's Kepler Space Telescope detected 1,235 alien planet candidates in its first four months of operation. Of those, 408 reside in multiple-planet systems, suggesting that our own configuration of multiple worlds orbiting a single star isn't so special.
What may be special, however, is the orientation of our solar system's planets. Some of them are tilted significantly off the solar system's plane, while most of the Kepler systems are nearly as flat as a tabletop, researchers said. [The Strangest Alien Planets]