Startship - The huge spacecraft that Elon Musk says will one day take people to Mars — failed during its latest test flight on Thursday when its upper stage exploded in space, raining debris and disrupting air traffic at airports from Florida to Pennsylvania. It was the second consecutive test flight of the most powerful rocket ever built where the upper-stage spacecraft malfunctioned. It started spinning out of control after several engines went out and then lost contact with mission control.