A US flag flown into space aboard Apollo 11 and signed by its crew is currently open for bids in Nate D Sanders' latest sale, which ends on July 23.
The flag is starting at $2,500, but it expected to rocket as the online sale draws to its close.
The four by six inch fabric flag has been mounted on a certificate that reads: "This flag travelled to the moon with Apollo 11, the first manned lunar landing, July 20, 1969".
Neil Armstrong, Buzz Aldrin and Michael Collins have each signed in felt-pen, though Armstrong's signature - the most valuable of the three - has faded.
Also starring in the sale is a space-flown Apollo 17 Robbins medal, which is one of just 80 flown aboard the mission.
It shares its $1,000 minimum bid with a space-flown flag and NASA patch that were flown aboard the STS-41-D Discovery mission.
The flag and patch were gifted by mission specialist Judy Resnik to her colleagues at Lockheed Missiles and Space Company, two years before she became one of the seven crew members who died aboard the Space Shuttle Challenger in 1986.
Paul Fraser Collectibles has a fantastic selection of space memorabilia for sale, including a remarkable, complete set of signed photographs from every astronaut who has walked on the Moon.