The slight warming of the moon surface observed in 1970s baffled NASA scientists, but data from "lost" tapes of Apollo missions found that astronauts' movements disturbed surface regolith and exposed darker soil, which then absorbed more of the sun's energy and increased subsurface temperatures.

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The slight warming of the moon surface observed in 1970s baffled NASA scientists, but data from "lost" tapes of Apollo missions found that astronauts' movements disturbed surface regolith and exposed darker soil, which then absorbed more of the sun's energy and increased subsurface temperatures.