A checklist used to guide the wounded Apollo 13 spacecraft home after the explosion that led to the famed "Houston, we've had a problem" call sold at auction in Texas Wednesday for just under $390,000.
The checklist booklet contains handwritten calculations by Commander James Lovell to determine the spacecraft's angle of descent back to Earth and other notes.
NASA transcripts show how Lovell asked Houston to "check my arithmetic to make sure we got a good course align." The three-man crew was running out of oxygen, water and heat and only had one chance to make it home safely.
The Apollo 13 Lunar Module Systems Activation Checklist fetched the highest price, at $388,375, for a piece of Apollo Space Program memorabilia that did not make it to the moon's surface, Heritage Auctions said.
"Without this (booklet) the Apollo 13 crew would not have known their position in space," said Michael Riley, senior historian at the Dallas-based auction house. "It helped create the greatest successful failure in the history of space exploration."
Apollo 13 was the seventh manned mission in the US space program and was supposed to be the third to land on the moon. But an oxygen tank exploded two days after its April 17, 1970 launch, badly damaging the spacecraft some 200,000 miles from Earth.
The booklet was sold to an anonymous collector who lives on the east coast of the United States.
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