http://www.slate.com/blogs/bad_astronomy/2015/10/14/weird_star_strange_dips_in_brightness_are_a_bit_baffling.html > “Aliens should always be the very last hypothesis you consider," Penn State astronomer Jason Wright told The Atlantic, "but this looked like something you would expect an alien civilization to build.” Basically Kepler has observed a star with dips in it's luminosity exponentially larger than any planet would cause. Even a Jupiter-sized planet would only account for a 1% drop. But the object or objects observed by Kepler cause a drop of up to 22%, indicating an object or cluster of objects roughly half the width of the star itself.