Scott Kelly, the NASA astronaut who just came back to Earth after nearly a year on the International Space Station, is retiring from the space agency on April 1. Kelly has been a part of NASA since 1996.

Kelly spent 340 days in space on his most recent mission, allowing scientists to gather a plethora of data about how the human body behaves during long periods in the extreme space environment.

“After spending an American record 520 days in space — including his Year in Space — I can think of no one more deserving of some well-deserved rest and time on the same planet as his family and friends,” was one of his statement while announcing his retirement.

In spite of the fact that he is leaving his NASA position, Kelly will keep taking part in the research started with his one-year mission on the Space Station.