One of the many items available in Sotheby’s inaugural space exploration-themed auction (occurring 19 July) is a bag of moon dust and rocks, collected by Neil Armstrong during the 1969 Apollo 11 mission. The bag (labeled LUNAR SAMPLE RETURN) was forgotten for years and then mistakenly auctioned off to Nancy Lee Carlson—who paid $995 for it and other items. Carlson ended up sending the bag to NASA to test its contents, and the mystery of the lost moon dust was explained—along with a legal battle between Carlson and NASA. It’s believed the moon dust will fetch up to $4 million at this summer’s auction. Find out more at Reuters.