A painstaking eight years of data recovery has lead a group of US scientists to finally figure out why the surface of the moon warmed up in the 1970s.
The scientists at Texas Tech University in Lubbock examined a set of lost NASA data tapes to measure the impact of human activity on the moon.
The researchers discovered astronauts from the Apollo moon landings disturbed the delicate surface of the moon enough to change the amount of sunlight being absorbed.
As a result of the lunar disturbance, the moon’s surface temperature spiked by one to two degrees Celsius.
Seiichi Nagihara, who led the research, said: “In the process of installing the instruments you may actually end up disturbing the surface thermal environment of the place where you want to make some measurements.
“That kind of consideration certainly goes into the designing of the next generation of instruments that will be someday deployed on the moon.”
The scientists concluded there is no feasible way for future manned missions to explore the moon without disturbing the delicate ecosystem.
During the Apollo 15 and 17 missions between 1971 and 1972, astronauts measured the Moon’s surface temperatures to establish if the natural satellite’s core is hot like the Earth’s.
The measurements were beamed back down to Earth and stored on magnetic tapes at the NASA Johnson Space Center in Houston from 1971 up until 1977.
But when the temperature measurements were ended in 1977, only a portion of the data was securely archived at NASA’s National Space Science Data Center.
A number of tapes from 1975 to 1977 were never properly archived and were presumed lost – until now.
In 2010, Dr Nagihara and a team of dedicated colleagues attempted to track down the tapes to figure out the lunar mystery.
The researchers uncovered 440 copies of archival tapes with temperature flow data from April through June 1975, quietly stashed away at the Washington National Records Center in Suitland, Maryland.
The scientists got their hands on hundreds of the weekly logs at the Lunar and Planetary Institute in Houston, where NASA scientists recorded heat flow figures from the moon.
Eight years after setting out on the venture, the scientists were able to reconstruct the missing data from everything they have uncovered.
Dr Nagihara said the data helped him figure out why activity around the lunar landing zones led to warmer surface readings.
The darker soil beneath the grey dust of the moon absorbs more sunlight, which makes it warmer, the scientists suspect.
Dr Nagihara said: “It doesn’t take much disturbance to get that very subtle warming on the surface.
“So analysis of the historic data together with the new images of the moon really helped us characterise how the surface warmed.”
The startling findings were published in the latest issue of the science journal Journal of Geophysical Research: Planets, a journal of the American Geophysical Union.