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When Neil Armstrong and Buzz Aldrin first walked on the moon in 1969 they knew that they were leaving a lasting mark in the annals of history. What they may not have realized was that they were also leaving a lasting mark on the surface of the Moon. Footprints on the Earth generally do not last very long since Earth has many ways of "repaving" its surface: rain, wind, weather, and plant growth in the short term, and vulcanism and plate tectonics over longer timescales. With no atmosphere, no life, and no active geology, the Moon has few ways of erasing the bootprints that were left by the NASA astronauts. Meteoroid impacts can kick up dust and smooth over small features over millions of years. In the short term, however, only careless future astronauts can destroy these bootprints of history.