Until recently, Fergal Mullaly worked for the science office of the Kepler space telescope, the planet-hunting satellite that has verified more than 2,600 planets so far. “We have this really strong emotional desire to be able to point to a place in the sky and say, ‘That star there has a planet around it,’” he says. For the four years of its main mission, from 2009 to 2013, Kepler fixed its gaze on one region of the sky and watched the light from its stars.

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