Martin can make it back to Mars since Mars has deviated from its regular orbit temporarily and is thus closer to Earth than usual. Martin has a 10 hour window of opportunity. Just as he is about ready to leave, he slips down the stairs and sprains his ankle, which also sprains his disappearing antenna. Mrs. Brown immediately calls an ambulance to the scene. When the ambulance physician takes Martin's vital signs, they rush him to the hospital since his vital signs aren't "human".