Former NASA astronaut Jonny Kim is returning to active-duty military service after nearly a decade with the space agency, closing a remarkable chapter that included work as an astronaut, engineer and International Space Station crew member.

Kim will continue serving as a lieutenant commander in the U.S. Navy and is expected to work in naval aviation training after leaving NASA.

Reflecting on his time with the agency, Kim said serving NASA and contributing to space exploration had been one of the greatest honors of his life. He emphasized that successful missions ultimately depend on people, teamwork, empathy and leadership.

Jonny Kim’s NASA Career and Space Mission

Kim joined NASA’s astronaut corps in 2017 and went on to hold several important roles before flying to space.

He served as a capsule communicator in Mission Control at Johnson Space Center in Texas and contributed to the Artemis program, which is focused on returning astronauts to the Moon. He also worked as an increment lead for Expedition 65.

In 2025, Kim spent about eight months aboard the International Space Station, where he conducted scientific research and participated in the day-to-day operations of the orbiting laboratory.

During the mission, he traveled more than 100 million miles while orbiting Earth thousands of times, adding spaceflight experience to an already extraordinary career.

From Navy SEAL to Doctor and Astronaut

Born in Los Angeles, Kim enlisted in the U.S. Navy in 2002 and later became a member of SEAL Team Three.

During two deployments to the Middle East, he completed more than 100 combat missions while serving in roles that included combat medic, sniper, navigator and point man.

His military service earned him several honors, including the Silver Star and Bronze Star with Combat “V.”

Kim later pursued medicine after experiences in combat convinced him that he wanted to do more for wounded service members and civilians.

He graduated summa cum laude with a bachelor’s degree in mathematics from the University of San Diego before earning a medical degree from Harvard Medical School.

Kim Also Became a Naval Aviator and Flight Surgeon

Kim’s career continued to expand after medical school.

He completed flight training at Naval Air Stations Corpus Christi and Whiting Field before undergoing aerospace medical training at the Naval Aerospace Medical Institute in Pensacola.

He ultimately qualified as both a naval aviator and flight surgeon, combining military aviation, medicine and operational experience.

His path to becoming an astronaut developed later, while he was already pursuing medicine and thinking about ways to continue challenging himself professionally.

A New Chapter in Military Service

Kim has previously described his time as a Navy SEAL as a defining period that reshaped how he viewed his own limits and future goals.

Combat experiences also played a major role in his decision to pursue medicine, while his later education and professional development ultimately led him toward NASA.

Now, after completing a career that has taken him from combat deployments to medical school and then to space, Kim is preparing to return to full-time Navy service.

He said he intends to carry forward his commitment to service, along with the lessons he gained from spaceflight, medicine and military leadership, as he begins the next stage of his career.

Kim’s transition back to active-duty service marks another chapter in one of the most diverse professional journeys in the U.S. military and space programs.