In the two decades since, Endeavour has left its mark on history, saving the Hubble Space Telescope, giving birth to the International Space Station (ISS), and completing a mission begun by the fallen shuttle it was built to replace. It also launched the first African-American woman and the first married couple. Now it is set to fly one last mission to the ISS to deliver a state-of-the-art experiment, a crowning achievement for an accomplished spacecraft. “Since Endeavour’s first flight to this flight, it’s had a really outstanding career,” said Capt. Mark Kelly, commander of Endeavour’s final mission, after arriving April 27 in Florida for the orbiter’s last launch.