Thinking there could be life on one of Jupiter’s moons, NASA scientists are working on a plan to send robots to begin studying it. Jim Green, NASA’s planetary science chief, said there’s no reason to think there isn’t life on Europa, the sixth-closest moon to the planet Jupiter and the sixth-largest moon in the solar system. And he can’t wait to find out. NASA administrator Charles Bolden said this week that the space agency’s 2015 proposed budget includes funding for a robotic mission to Europa.