Contributing to Space Exploration and Serving NASA Has Been the Honor

Jonny Kim, a former Navy SEAL who spent the last decade as a NASA astronaut and engineer, is returning to active-duty military service, NASA announced. Kim will leave the space agency Thursday and continue serving as a lieutenant commander in the U.S. Navy, working in naval aviation training. "Contributing to space exploration and serving NASA has been the honor of a lifetime, Kim said.

"Throughout my career, I've learned that beyond the missions, the training, and the hardware, success always comes down to the people. They are our greatest asset, and leading with love and empathy is how we achieve the impossible. Kim conducted scientific research aboard the International Space Station for eight months in 2025, traveling over 104 million miles, NASA said.

He became a NASA astronaut in 2017, served as a capsule communicator in the Mission Control Center at Johnson Space Center in Texas, helped develop the Artemis program — which aims to launch U.S. astronauts back to the moon by 2028 — and served as an increment lead for Expedition 65. Born in Los Angeles, California, Kim enlisted in the Navy in 2002 and joined SEAL Team Three, completing over 100 combat missions as a combat medic, sniper, navigator and point man during two deployments to the Middle East. He earned the Silver Star, the nation's third-highest award for valor, and the Bronze Star with Combat "V, among other awards. Kim was later commissioned into the medical corps through the Naval Reserve Officers Training Corps.

He graduated summa cum laude with a bachelor's degree in mathematics from the University of San Diego and earned a doctor of medicine from Harvard Medical School. He also became a naval aviator and flight surgeon simultaneously, completing flight training at Naval Air Stations Corpus Christi in Texas and Whiting Field in Florida, plus aerospace medical training at the Naval Aerospace Medical Institute at Naval Air Station Pensacola. Kim previously told Military Times that when he joined the Navy, he had no lofty plans beyond becoming a SEAL.

Deploying to Ramadi in 2006 as a corpsman, he felt helpless trying to save lives because he could only stabilize patients before handing them to a surgeon — a moment that sparked his interest in medicine. While in medical school, thoughts of becoming an astronaut first emerged." "I look forward to carrying my commitment to service, my enduring love for space and technology, and the hard-earned lessons of this past decade into my next chapter to make a meaningful impact on humanity's future, Kim said." He added that being a SEAL was certainly a memorable experience because it redefined new limits, gave me new benchmarks on how to judge the rest of my life.