NASA scientists in charge of the Kepler Mission have discovered an unprecedented solar system in which two planets with different densities and compositions are locked in a close orbit around their star. The finding shows that there is much greater diversity in the composition of solar systems than we'd previously thought.
The discovery of enormous inner system gas giants made the conceptions of what other systems might look like put into question. With the discovery of these two new exoplanets, our imaginations are proving to be completely inadequate.
Called Kepler-36, it is 1,200 light years away, and one of its planets is a rocky super Earth, 1.5 times the size of our planet and 4.5 times the mass. It's companion, a Neptune gas like planet, is 3.7 times the size of Earth and 8 times the mass. They are very very close to each other, making it 30 times closer than any pair of planets in our solar system.
This discovery will have an impact on emerging theories about planet migration and orbital rearrangement. Prior to this, scientists had assumed that small rocky planets form in the hot part of the inner solar system, and the bigger less planets can only be formed far away from the host star.
But the discovery of Kepler-36 messes this all up. Astronomers will have to figure out how the two planets with such different densities are in nearly identical orbits.