Volunteers for the Planet Hunter project have discovered a planet that is part of a four-star system. The planet, named PH1, orbits a pair of stars that is itself orbited by a more distant pair of stars.

The Planet Hunter project is a citizen science project that collaborates with Yale University and other organizations to cull through the light curves taken by NASA’s Kepler spacecraft. Planet Hunters search the data for the brief dip in brightness that occurs when a planet passes in front of its star.

NASA announced this week that a Yale-led team of astronomers has confirmed the discovery of this circumbinary planet in a four star system. According to NASA, only six planets are known to orbit binary stars, though none of them are orbited by distant binary stars.

“I celebrate this discovery as a milestone for the Planet Hunters team: discovering their first exoplanet lurking in the Kepler data,” said Natalie Batalha, Kepler scientist at NASA’s Ames Research Center. “I celebrate this discovery for the wow-factor of a planet in a four-star system. Most importantly, I celebrate this discovery as the fruit of exemplary human cooperation — cooperation between scientists and citizens who give of themselves for the love of stars, knowledge and exploration.”

PH1 is slightly larger than Neptune and is thought to be a gas giant. It orbits its stars every 137 Earth days.

A research paper on the phenomenon was presented this week at the annual meeting of the Division of Planetary Sciences of the American Astronomical Society. It has also been submitted to The Astrophysical Journal.

Earlier this year NASA announced that Kepler had found a planet orbiting a binary star. Like Tatooine.

(Photo courtesy Haven Giguere/Yale)