The reaction to the snap on Twitter was overwhelmingly positive, with many users praising Collins' post.
"This is totally the best crew shot! Thank you so much for sharing. Bless," one Twitter user, @Stephen_Weisser, said.
"Awesome pic!! Keep finding those hidden gems!! Big fan of the Apollo missions and all you guys did. True American heroes!!" another user, @snowrob0, wrote.
While photos of the three astronauts together are not exactly rare, the newly found one is unusual in some respects, the Sentinel reported.
Firstly, Collins is standing separately from Armstrong and Aldrin—quite different to most crew photos which tend to show the trio standing or sitting together. The second interesting feature is that Armstrong's hand is placed amiably on Aldrin's shoulder. It is well-known that the pair, while always respectful of each other, were not exactly the closest, despite being part of such a historic experience.
In fact, Collins has previously described the relationship between the two as being like that between "neutral strangers" or "amiable strangers." This could, in part, have been down to their very different personalities, with Aldrin often characterized as an extrovert while Armstrong was more of an introvert.
Michael Collins—one of the three crew members of the historic Apollo 11 moon mission—has posted a previously unreleased NASA photo on Twitter of himself, Buzz Aldrin and Neil Armstrong, which he discovered by chance in a box.
The photo—taken in 1969—shows the trio, decked out in full astronaut gear, standing next to a moon prop with Aldrin and Armstrong on one side and Collins on the other. The picture also features Collins' autograph scrawled over the top in black ink.
"The crew. Found this at the bottom a box. Don't think it was ever used by @NASA. #TBT @TheRealBuzz," Collins tweeted.
The release of the photo is a fitting tribute to the mission in the year of its 50th anniversary, especially because it has likely not been seen by human eyes for five decades.
Florida news outlet The Orlando Sentinel—which is about to publish a commemorative book on the 1969 mission—reported that no staff members could remember seeing the photo before either in the NASA archives or the paper's own records.