On May 7, 1992, Space Shuttle Endeavour roared into the sky on its very first mission. NASA had built Endeavour to replace the Shuttle Challenger, which was destroyed in a tragic accident in 1986. Endeavour was the newest shuttle in the fleet. It included better computers and other upgrades that the older shuttles did not have. The first mission lasted almost nine days. The crew of seven had an important job. A communication satellite called Intelsat VI was stuck in a useless orbit too low above the Earth. Three astronauts performed a daring spacewalk to grab the satellite. They attached a new rocket motor to it. Then they released it, and the motor pushed the satellite into the correct orbit. This was the first time three astronauts had walked in space at the same time. Rescuing a satellite that weighed as much as a school bus was no small feat. Endeavour flew twenty-five missions over the next nineteen years. It helped build the International Space Station and carried science experiments into orbit. The shuttle made its final flight in 2011 and now rests in a museum in Los Angeles.