The inside of Columbia, complete with graffiti (Photo: Smithsonian Institution)

On their journey to the moon in 1969, the Apollo 11 astronauts left behind little bits of graffiti all over their command module, Columbia.

Recently, the National Air and Space Museum discovered previously unknown examples of these scribbles, while creating a 3-D scan of Columbia in order to make an interactive model of the spacecraft.

Being astronauts, the crew of Apollo 11 left behind very responsible graffiti. The museum found coordinates for the lunar module’s position on the moon and a practical addition to the labeling of a storage bin. The astronauts had stored the urine bags they used before the waste-management system started functioning in a storage bin, so they wrote on that storage bin “Launch Day Urine Bags.”

The most poignant of the graffiti that the researchers found was a tiny, neat calendar displaying the days of the mission. Each day was marked off with an X; only the last day of the mission, July 24, was left unmarked.

Bonus finds: A tiny letter sent by balloon in 1870, stegodon tusk, new species of extinct flower preserved in amber

Every day, we highlight one newly lost or found object, curiosity or wonder. Discover something unusual or amazing? Tell us about it! Send your finds to sarah.laskow@atlasobscura.com.