The astronaut is stepping away from NASA shortly after returning from a troubled test flight that left him aboard the ISS months longer than expected.

NASA has announced the retirement of test pilot and astronaut Butch Wilmore after 25 successful years of service and flights aboard four different spacecraft. Wilmore, a veteran pilot and graduate of the U.S. Naval Test Pilot School, has logged 464 days in space since his selection by NASA in 2000.

Veteran NASA astronaut Butch Wilmore has retired after 25 years of service, after completing the troubled Boeing Starliner mission. Wilmore, who flew on four different spacecraft and logged 464 days in space,