Commander Chris HadfieldCanadian-born International Space Station Commander Chris Hadfield, following up on a brief communication via Twitter that caught the attention of Star Trek fans and space exploration afficionados alike, conducts a live video chat from orbit with Star Trek star William Shatner (speaking from Earth). The two discuss the risks of space exploration and the technological leaps forward (including means of communication that were strictly science fiction in Star Trek’s heyday), though Shatner can’t convince Hadfield to confirm rumors that the astronaut has volunteered to head up a mission to Mars.