Astronaut Scott Kelly to Retire from NASA

Astronaut Scott Kelly will retire from NASA in April, less than a month after returning from a year in space, the agency announced Friday,

Kelly will continue to participate in research related to his year-long time in the International Space Station. Scientists are studying the effects of his journey on his body and comparing those results with similar tests conducted on his twin brother who remained on earth.

“This year-in-space mission was a profound challenge for all involved,” Kelly said in a press release. “It gave me a unique perspective and a lot of time to reflect on what my next step should be on our continued journey to help further our capabilities in space and on Earth.”

Kelly’s final space mission—the longest ever of any American—was his fourth journey into space. He returned to Earth in early March and declared “this feels great.”

Subscribe to TIME

Get our Space Newsletter. Sign up to receive the week's news in space.

Please enter a valid email address.

* The request timed out and you did not successfully sign up. Please attempt to sign up again.

Sign Up Now

An unexpected error has occurred with your sign up. Please try again later.

Check the box if you do not wish to receive promotional offers via email from TIME.

You can unsubscribe at any time. By signing up you are agreeing to our Terms of Service and Privacy Policy. This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Thank you!

For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder.

Write to Justin Worland at justin.worland@time.com.