The retired camera lens from the 1971 Apollo 15 Moon mission is expected to rake up around $600,000 at the RR Auction, with April 21 as the bidding deadline. The camera lens was both used while in orbit and on the Moon's surface by a former NASA astronaut.

The 12-inch long, Zeiss Tele-Tessar 500mm f/8 lens was used by Apollo 15 spacecraft commander David Scott. During the Apollo 15 mission, the lens was used to take 293 photographs.

"The silver lens measures 12″ long and is engraved near the mount with NASA part numbers, 'SEB 33100284-S/N 1006.' Special tabs were fitted to the rotational segments in the center of the lens, used to adjust focus and f-stop, for ease of use with the pressurized gloves of a spacesuit," described RR Auction on its website.

The lens' body is fastened with several Velcro tabs. The lens' cap and rear end are secured with duct tape. The item bears the signature 'D. R. Scott' on its rear end, which was written using a felt tip pen.

The camera's silver exterior was chosen so the camera and lens could keep the devices' internal temperatures uniform despite the extreme heat conditions on the Moon's surface. Similar to other mementos from lunar missions, the lens displays signs of extensive use in space but its space history could more than make-up for this wear and tear condition.

The camera lens comes with a detailed letter from the NASA astronaut himself. Scott certified that the Zeiss f8/500 mm Tele-Tessar lens came from his own personal collection. He also confirmed that is was attached to his Hasselblad Electric Data Camera (HDC), which he also used in orbit and on the Moon's surface during the space mission.

The now 83-year-old Scott said in the letter, which accompanies the sale, that NASA gave the camera lens to him as a reminder of his lunar mission. Prior to this auction, the lens has been in Scott's personal collection since it was given to him by the American space agency.

RR Auction's online bidding for the Zeiss Tele-Tessar 500mm f/8 lens started on April 14. Expecting to go over $600,000, the bidding will close on April 21.