The warm and engaging "Good Night Oppy" isn't a Disney or Pixar movie, but a lot of times it feels like one. Directed by Ryan White ("The Keepers," "The Case Against 8"), it's a documentary about the mission to explore the surface of Mars with remote-controlled, unmanned robots, named Spirit and Opportunity. The mission began with preplanning in 2003 and continued all the way through 2018. This was a surprise to the NASA scientists and engineers in charge, who had gone into it assuming the robots might last a few months at best.