NASA announced earlier this week they have discovered a gas giant about the size of Jupiter, orbiting a two-star system, roughly 3700 light years away.
We all remember in the beginning of Star Wars – Episode IV: A New Hope Luke Skywalker looking hot (and that has nothing to do with him being on a desert planet), watching the two suns set on the horizon while John Williams’ music the Force Theme swells in the background.
Now you’re saying, “Hey! Tatooine isn’t a gas giant. It’s just a rock in space!”
True, but planet Kepler-1647b is in the “habitable zone” a range of distances from a star where liquid H2O could exist on the surface of a planet. Although Kepler-1647b is a gas giant, there is the possibility it has moons large enough to sustain life.
Kepler-1647b is not the only planet found to be orbiting two suns but it is the largest. It takes 1107 days to complete a single orbit which is the longest of any exo-planet discovered so far, which is why it took so long to confirm it. Its transit across its suns was noted back in 2011 from data acquired by the Kepler Space Telescope launched in 2009. The telescope discovers planets when they cross in front of their host sun, causing a dip in the sun’s brightness.
The Kepler Space Telescope’s initial observations ended in May 2013, when two of the four orientation-maintaining reaction wheels failed, but scientists still have mountains of data to sort through. In 2014, mission members found a way to stabilize Kepler using “sunlight pressure”. So Kepler is back in business and has discovered over 2200 alien planets to date.