A letter written by Albert Einstein to a colleague politely declining to write the foreword to his book was the top lot of a sale of science and space related memorabilia at Nate D Sanders on September 26 when it sold for $6,544.
The letter, which dates to June 10, 1938, also makes a brief reference to quantum theory, further increasing its appeal.
Other lots at the sale included a flag flown on the Apollo 8 mission which sold for $5,948, and a flag from the Apollo 13 mission, which sold for $4,468. Both lots featured certificates signed by the astronauts themselves.
You can view our collection of space memorabilia here.
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