A NASA space suit test robot developed during the early 1960s is selling at RR Auction.
The piece is expected to make in excess of $80,000 when it auctions on September 26.
It was created by the IIT Research Institute to test the limitations of new space suits.
It's capable of a range of 35 different motions, with sensors on the joints set up to feed data back to technicians.
Unfortunately the team could not get the hydraulic system right (it leaked constantly) and so the project was shelved.
As the auction house comments: "Nevertheless, this remarkable robot stands as a testament to the innovative creativity NASA inspired in its quest skyward."
Only two such robots were produced; the other is housed in the Smithsonian.
A typed letter signed by Buzz Aldrin and Neil Armstrong is valued at more than $15,000.
It's addressed to a woman in Hawaii in response to her question of what they planned to say when they arrived at the Moon.
It reads in full: "Colonel Aldrin and I appreciate your taking the time to write us for your suggestion on a message from the lunar surface.
"We do not know at this time what our inclination will be should we be successful in our landing attempt.
"I certainly hope you will be pleased with whatever message we do have and the impressions that people on earth receive from our efforts."
Famously Armstrong would go with: "That's one small step for (a) man, one giant leap for mankind."
He claimed to have come up with the quote just before exiting the lander.
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