Lost moon tapes have helped solve the 40-year-old mystery of an unusual warming of the lunar surface – it was man-made climate change caused by astronauts tooling around up there.
The website Science Alert reported that astronauts kicking up dust on the moon’s surface after drilling probes into the lunar surface during Apollo 15 and Apollo 17 missions caused the warming spike, according to a study published in the Journal of Geophysical Research: Planets.
Texas Tech researchers, who found the missing data in 2010 at the Washington National Records Center, painstakingly restored the information and learned that the moon's warming recorded by probes was because of the astronauts and their lunar rovers, Science Alert said.
The moon's temperature was monitored July 1971 to January 1977 at the Apollo 15 site and from December 1972 to September 1977 from the Apollo 17 location.
Much of the data eventually went missing but some of the data still on hand showed a warming, surprising scientists.
The Texas Tech researchers found 440 of the lost tapes, covering April through June 1975, but they were badly degraded, Science Alert said. Over the past eight years, the researchers used data recovery techniques to restore the tapes.
While the discovery only accounted for 10 percent of the lost tapes, hundreds of weekly logs that included temperature readings from the probes from 1973 to 1977 were used to make up for the missing information.
The information helped researchers come to the warming conclusions.
"We suggest that, as a result of the astronauts' activities, solar heat intake by the regolith increased slightly on average, and that resulted in the observed warming," the researchers said in the abstract from the Journal of Geophysical Research.
"Simple analytical heat conduction models with constant regolith thermal properties can show that an abrupt increase in surface temperature of 1.6 to 3.5 (Kelvin) at the time of probe deployment best duplicates the magnitude and the timing of the observed subsurface warmings at both Apollo sites."
Researchers believed, according to Newsweek, that the best indication that humans caused the temperature increases was that the warming was stronger on the surface and faded in measurements taken deeper in the moon, suggesting that the warming did not come from inside the moon.
Researchers said astronauts and the rovers also kicked up darker surface dirt, or regolith, which absorbs heat and continues to attract more of the sun's heat over the years.