Newfound ’Tatooine’ Alien Planet Bodes Well for E.T. Search
The planet, known as Kepler-47c, is a gas giant and therefore probably not suitable for life as we know it. But its existence hints that smaller, rockier worlds may inhabit other two-star systems’ habitable zones —that just-right range of distances where liquid water can exist.
And that’s important, because there are a lot of binary systems out there, scientists say.
"Roughly half of the stars in the galaxy are in binary systems," study lead author Jerome Orosz, of San Diego State University, told SPACE.com. "I thought it would only be a matter of time before we found a system like Kepler-47 where a planet is in the habitable zone."
This illustration shows the orbits of the two alien planets circling two stars of Kepler-47, and the orbits of our own solar system planets for comparison.
The Kepler-47 system, whose discovery was announced Tuesday (Aug. 28), dwells about 5,000 light-years away, in the constellation Cygnus (The Swan). It is a close binary system, with two stars orbiting near each other at its center. Around these stars whirl two planets known as Kepler-47b and Kepler-47c.
They make Kepler-47 the first system seen with multiple worlds circling a pair of stars.
"If single stars and close binary stars can host planetary systems with an equal probability — that is not at all clear at the moment — then it would follow that life could be just as common on circumbinary planets as on planets with single stars," Orosz said.
Read the full article at: space.com