Apollo 11 astronaut Michael Collins has shared a previously unseen photo of the three-man crew who went to the moon for the first time. 

The photo shows Collins, Neil Armstrong and Buzz Aldrin posing alongside a model of the moon, where they were soon headed. Collins had signed the photo as some point. 

"The crew. Found this at the bottom of a box. Don't think it was ever used by @NASA," Collins wrote, with a hashtag #TBT for "throwback Thursday."

The crew. Found this at the bottom of a box. Don’t think it was ever used by@NASA.#TBT@TheRealBuzzpic.twitter.com/ZXINsWPcix

— Michael Collins (@AstroMCollins)June 13, 2019

Collins was stationed in the Columbia Command Module while Armstrong and Aldrin walked the moon July 21, 1969. The crew landed on the moon the day before. 

NASA has a list of multiple events scheduled to celebrate Apollo 11's 50th anniversary this year, including museum exhibits across the U.S. and panels. On July 19, there will be a live broadcast on NASA's Live page from historic sites on Earth, like newly-restored Apollo mission control room at NASA's Johnson Space Center in Houston and Neil Armstrong’s hometown of Wapakoneta, Ohio. 

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