Bidding on a flown "type 1" Apollo 11 cover stands at $16,838 ahead of a November 11 sale at RR Auction.
The lot bears signatures from Michael Collins, Buzz Aldrin and Neil Armstrong.
It's accompanied by provenance from Collins that reads: "I hereby certify that the accompanying Apollo XI official commemorative cover, numbered C-58 within the earth image, further identified with the August 11, 1969 Webster, TX postmark, the Lunar Receiving Laboratory quarantine stamp and the original signatures of the crew, is one of my 63 covers that flew to the moon with me aboard the mission July 16-24, 1969."
The covers are among the most coveted items in the space collecting hobby, with one specimen selling for $46,000 at Christie's in 1999.
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