Apollo footprints on the Moon could last for at least a million years.

On Earth, a footprint is temporary by default. Wind, rain, water, plants, and people erase it. The Moon does not work that way. The American Museum of Natural History explains that lunar “impact gardening” is so slow that Apollo astronauts' footprints will last for at least a million years. NASA also notes that the Moon has only an extremely sparse atmosphere, so the usual Earth-style weathering is missing. Micrometeorites will eventually disturb the marks, but not on a human timescale. A bootprint can outlast cities, languages, and maybe civilizations.

1 discovery explored