Sizes of Kepler Circumbinary Planets
Comparison of the relative sizes of several Kepler circumbinary planets. Kepler-1647 b is substantially larger than any of the previously known circumbinary planets. NASA/Lynette Cook

In mid-May, the National Aeronautics and Space Administration (NASA) announced the discovery by the Kepler Space Telescope of 1,284 new planets, instead of alien life as some groups were speculating. Make that now 1,285 new planets with the discovery of a planet similar to Jupiter with two suns.

Space.com compares the newly discovered plant to Tatooine, the planet of “Star Wars’” character Luke Skywalker in the franchise Hollywood movie. But unlike the movie planet which is small and rocky, Kepler-1647b is a gas with about the size and mass of Jupiter.

It has the widest orbit, taking 1,107 Earth days to circle its two host stars, according to astronomers. The newly discovered planet is with the habitable zone of its stars, which means its distance allows liquid water to be stable on the planet’s surface. However, as a gas planet, it does not have a surface.

NASA announced on Monday the discovery of Kepler-1647b during a meeting of the American Astronomical Society. A team of astronomers from the NASA Goddard Space Flight Center in Greenbelt, Maryland, and San Diego State University (SDSU) in California discovered the new planet.

It is too faint to see with the naked eye when looking at the constellation Cygnus. The planet is 3,700 light-years away and about 4.4 billion years old, or about the same age as Earth. Its stars are similar to Earth’s Sun, one is slightly larger than the other.

Besides being known as Tatooine, planets which orbit two stars are also called circumbinary planets. Astronomers, who used Kepler data, search for a slight decrease in brightness as hint that a planet could be passing or transiting in front of a star which would block a small amount of the light from the star.

“But finding circumbinary planets is much harder than finding planets around single stars. The transits are not regularly spaced in time and they can vary in duration and even depth,” explains William Welsh, SDSU astronomers. He is one of the co-authors of the study accepted for publication in the Astrophysical Journal. The lead author is Veselin Koslov, a NASA Goddard postdoctoral fellow.

VIDEO: Jupiter-Sized Planet Orbiting Two Star System is Largest Found Yet

"