Alexander Gerst is a German European Space Agency astronaut and geophysicist, who was selected in 2009 to take part in space training. He was part of the International Space Station Expedition 40 and 41 from May to November 2014. Gerst returned to space on June 6, 2018, as part of Expedition 56/57. He was the Commander of the International Space Station. He returned to Earth on December 20, 2018. After the end of his second mission and before being surpassed by Luca Parmitano in 2020, he held the record for most time in space of any active ESA astronaut, succeeding Italian astronaut Paolo Nespoli, and German ESA astronaut Thomas Reiter, who formally held the record for the longest time in space for any active or retired ESA astronaut.