An Apollo 11 flown flag, mounted on a crew-signed presentation certificate, made $71,875 at Heritage Auctions' Space Exploration Signature Auction in Dallas on November 1.
The lot eclipsed its initial estimate of $25,000-35,000 - achieving a 105% increase.
The item features the autographs of all three astronauts on the Apollo 11 mission, and comes from the collection of Paul M Sturtevant - a long-time NASA employee who worked on the Gemini program in the early 1960s.
It features bright colours and bold signatures, with none of the bleed-through from the glue often seen on similar pieces - and now bears the distinction of being one of the most valuable examples ever sold.
An Apollo 11 flown cover, from the personal collection of the mission's command module pilot, Michael Collins, realised $46,875. Signed by all three crewmembers, the cover features an 8c Apollo 8 stamp with an August 11 cancellation.
Beneath the cancellation is the text "Delayed In Quarantine At/ Lunar Receiving Laboratory/ MSC - Houston, Texas".
This is a reference to the quarantine period the astronauts and equipment underwent from July 24, 1969.
Just 214 Apollo 11 flown covers are known to exist.
An EKG strip from an Earth-based electrocardiogram machine that was monitoring Armstrong's heartbeat as he stepped on to the surface of the Moon made $35,000.
It is taken from the exact moment that he made his legendary "One small step for a man" speech.
Memorabilia pertaining to the Apollo 11 mission has seen steady price growth in recent years, making it a strong investment proposition.
We have a variety of space memorabilia for sale, including this complete set of signed photographs from each of the 12 astronauts to walk on the Moon.
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