During Apollo 14 in 1971, command module pilot Stuart Roosa, a former Forest Service smokejumper, carried a canister of roughly 500 tree seeds into lunar orbit at the request of Forest Service chief Edward P. Cliff. Loblolly pine, sycamore, sweetgum, redwood, and Douglas fir seeds were exposed to radiation and microgravity, then germinated at stations in Gulfport, Mississippi and Placerville, California. About 420 seedlings survived, and after more than 40 years of comparison with earthbound controls, scientists found no difference at all, which the episode argues is a reassuring result for future lunar and Martian habitats.

Distributed for the 1976 Bicentennial to the White House, state capitals, universities, and foreign recipients including Emperor Hirohito, the moon trees were then simply forgotten as NASA turned to the Space Shuttle. In 1996 a third grade teacher in Indiana named Joan Goble emailed NASA about a plaque her students found, and Dave Williams at Goddard began a Web 1.0 crowdsourced hunt to rebuild the lost registry. The story continues with the Moon Tree Foundation growing second-generation trees and NASA sending a thousand new seeds aboard Artemis I in 2022, now studied with epigenetics and deep DNA sequencing.

• How gravitropism and statoliths let a seed know which way is down, and why NASA wanted to test it
• Why finding zero mutations after 40 years counts as a scientific victory
• The Bicentennial planting campaign and the bureaucratic memory lapse that followed
• Joan Goble, Dave Williams, and the 2011 Wired article that turned the search into a global treasure hunt
• Artemis I seeds, the 2024 distribution to schools, and what epigenetics can reveal that 1970s tools could not