On March 7, the fifth day, came "the key event of the entire mission: the separation and rendezvous of the lunar module and the command module". The lunar module lacked the capability to return the astronauts to Earth; this was the first time space travelers had flown in a vehicle that could not take them home. McDivitt and Schweickart entered the LM early, having obtained permission to do so without wearing their helmets and gloves, making it easier to set up the LM. When Scott in "Gumdrop" pushed the button to release the LM, it initially hung on the latches at the end of the docking probe, but he hit the button again and "Spider" was released. After spending about 45 minutes near "Gumdrop", "Spider" went into a slightly higher orbit, meaning that over time, the two craft would separate, with "Gumdrop" ahead. Over the next hours, McDivitt fired the LM's descent engine at several throttle settings; by the end of the day the LM was thoroughly test-flown. At a distance of , "Spider" fired to lower its orbit and thus begin to catch up with "Gumdrop", a process that would take over two hours, and the descent stage was jettisoned.