A Duro Rocket felt tip pin used on the lunar surface by astronaut Alan Bean is to star in a space memorabilia sale at RR Auction.
The lot was carried on the Apollo 12 mission, the second to land on the Moon, and carries an estimate of $30,000-40,000 ahead of the October 20 sale.
The problem of writing in space was surprisingly tricky to overcome.
There's a persistent urban legend that NASA spent millions developing a pen that worked in zero gravity, while the Russians just used pencils.
In reality, it can be dangerous to use pencils in space as the minute shavings can find their way into delicate instruments and an outside company developed the Space Pen - which is still standard issue aboard the International Space Station today.
Felt tips were used briefly during the Apollo era but were temperamental as they work best in low pressure conditions (effectively the opposite of a space shuttle).
In total 27 Rocket felt tip pens were carried to the Moon and only 12 were brought back.
Bean explains in a letter of provenance: "I hereby certify that the accompanying felt tip pen travelled with me to the lunar surface on the Ocean of Storms in November 1969.
"I used this pen in our command module, Yankee Clipper, on the way to and from the moon. I used it during descent, and landing on the moon, inside our lunar module, Intrepid, and on liftoff to rendezvous with the orbiting command module.
"I carried it in my right arm pocket during both moonwalks."
Another, belonging to Apollo 9 commander James McDivitt, made just $2,270 in 2010, showing the premium buyers place on pieces that were carried on to the surface of the Moon.
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