Scott Kelly To Retire From NASA After Spending A Year In Space

There are many impressive ways to bow out of your job, but perhaps breaking the record for the longest single U.S. spaceflight and becomingone of the first two humans to spend a year aboard the International Space Station (ISS) tops them all.

Yes, NASA has announced that one-year crew member Scott Kelly, 52, will retire from being an astronaut with the agency as of April 1 this year. He will still take part in research related to his year-in-space mission, namely the Twins Study in partnership with his brother Mark, but his days of actually going to space are now over.

This year-in-space mission was a profound challenge for all involved, and 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 said in a statement.

Kellys career was glittering, to say the least. In total, he spent 520 days in spacethe most for any American astronaut (so far), across four missions. It was his latest mission that really threw him into the limelight, though, where Kelly became known not only for his prolific tweetingfrom space (700 in total), buttogether with his Russian counterpart Mikhail Kornienko, he alsobecame the first to spend 12 months on the ISS. Previous missions lasted just six months.

Missions like this are a vital step towards sending humans to Mars, and NASA has more plans for similar (oreven more ambitious) missions on the ISS in the future. Our universe is a big place, and we have many millions of miles yet to explore, Kelly said in a personal blog post onFacebook.

Kelly is seen here during a spacewalk on November 6, 2015. NASA

His 520-day record wont last forever, though, as NASA astronaut Jeff Williams is set to launch to the ISS on March 18, and on this mission he will reach a total of 534 days.

Nonetheless, Kellys achievements, particularly with regards to setting humans towards Mars, will not be forgotten. When honoring Kelly, perhaps NASA Administrator Charles Bolden summed it up best:

When the first Americans set foot on Mars, they will be following in the footsteps of one of the finest astronauts in the history of the space program, my friend, Commander Scott Kelly. After spending an American record 520 days in space including his Year in Space I can think of no one more deserving of some well-deserved rest and time on the same planet as his family and friends.

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