You might think that, with a thick atmosphere, Earth’s Moon is a cold and desolate little ball of orbiting rock, right? Wrong. The surface temperature of the Moon ranges from 100° C (212° F – boiling temperature, kids) during the day to -173° C (-343° F) at night. For comparison, the hottest temperature ever recorded on Earth was 138° F (in the Libyan Desert) and the coldest was -126° F (at Vostok Station, Antarctica).
Among their experiments, the Apollo 15 and 17 missions were tasked with monitoring heat still radiating from the Moon’s long-dead core. After accounting for sunlight on the surface and the heat caused by the drills themselves, the results appeared to be pretty straightforward.
But something wasn’t quite right: the probes showed higher heat increases in the area surrounding the Apollo landing sites, creating a strange heat anomaly that couldn’t be accounted for. Even stranger, the anomaly has persisted for years after the Apollo missions returned to Earth. In the end, some detective work from a Texas Tech team revealed what was causing the strange heating effect: albedo.
In space jargon, albedo is “the proportion of the incident light or radiation that is reflected by a surface, typically that of a planet or moon.” After looking at video recordings of the lunar surface taken during the missions and comparing the heat data from the probes, the Texas team realized that the heat increases were happening first at the surface, then deeper in the ground. This led them to uncover the real reason for the anomaly:
It turns out that the real reason for climate change on the Moon was the Apollo astronauts themselves all along.