Alien World Is Biggest 'Tatooine' Planet with 2 Suns Ever Found

A newfound alien world is the biggest ever discovered that has two suns in its sky, like Luke Skywalker's home planet of Tatooine in the "Star Wars" universe.

Whereas the fictional Tatooine is a small and rocky world, however, the real-life Kepler-1647b is a gas giant about the size and mass of Jupiter. In addition to being the biggest known two-star planet, Kepler-1647b also has the widest orbit, circling its host stars in 1,107 Earth days, astronomers said.

And the planet's intriguing characteristics don't stop there. Kepler-1647b also resides in its stars' "habitable zone," the range of distances at which liquid water could be stable on a world's surface. Kepler-1647b is a gas giant, so it doesn't have a surface — but any moons circling the huge planet could conceivably be capable of supporting life as we know it, study team members said. [10 Real Exoplanets That Resemble Star Wars Worlds]

Kepler-1647b was discovered by NASA's Kepler space telescope, which launched in March 2009 on a mission to determine how common Earth-like planets are throughout the Milky Way galaxy.

Kepler spots alien planets by noting the brightness dips that are caused when the worlds cross their host star's (or in this case stars') faces from the instrument's perspective. The spacecraft generally needs to observe three such "transits" to identify an exoplanet — which means that distantly orbiting worlds take longer to find.