Katherine Megan McArthur (born August 30, 1971) is an American oceanographer and a National Aeronautics and Space Administration (NASA) astronaut. She has served as a Capsule Communicator (CAPCOM) for both the space shuttle and space station. Megan McArthur has flown one space shuttle mission, STS-125, where she served as Mission Specialist in repairing the Hubble Space Telescope. McArthur has served in a number of positions including working in the Shuttle Avionics Laboratory (SAIL). She is currently in space as the Commander of the NASA SpaceX Crew-2 mission to the ISS. She launched on 23 April 2021.