Apollo 17 Mission Commander Eugene Cernan drives the traveling transport Tacha.
(CNN)– NASA’s Apollo missions in the 1960s and 1970s not only brought Americans to the surface, but even answered important portraiture questions that could only be answered by traveling there.
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Like so many times, these answers sometimes raise more questions or, as in this case, a permanent headache.
During the Apollo 15 and 17 missions in 1971 and 1972, astronauts installed probes in two locations to determine the temperature of the mirror’s basement. The Apollo software ended in 1972, but raw surface temperature data above and a few meters below were transmitted by the probes and recorded on magnetic tape at NASA’s Johnson Space Center from 1971 to 1977.
In 1974, the temperature below the surface of the portrait unexpectedly rose from -7 degrees Celsius to 2 degrees Celsius near the polls. Planetary scientists have debated possible reasons for this shift for decades. The riddle was not deepened until tapes from the book explaining temperature data from 1975 to 1977 were lost.
For eight years, a team of researchers has been dedicated to recovering the missing data and solving the enigma. From now on, their new discoveries and the data recovered from the work of Apollo can see the light of day. The study was published this month in the Journal of the American Geophysical Union.
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A secret that lasted for decades.
The goal of the Apollo heat flux experiment is to determine the rate at which the plane loses thermal energy, wrote Walter Kiefer, study author and senior scientist at the Missing and Planetary Institute in Houston, in an email.
“This is important because it controls the rate of internal geologic activity in the portrait,” Kiefer said. “For context, thermal energy leaving Earth drives the rate at which Earth’s geological plates move, widening mountain ranges, seismic activity and volcanic eruptions.”
Once the original temperature data was recorded on tape, it was sent to task scientists for investigation and archiving. But the tapes from 1975 to 1977 have never been archived.
Apollo 17 Mission Commander Eugene Cernan drives the traveling transport Tacha.
“The puzzle persisted for so long because no one was working on this problem,” Kiefer said. “NASA started trying to recover data from old missions [Apollo y otras naves espaciales] in 2010, when our team started working on this problem. »
A separate set of archival tapes containing data from April through June 1975 was found at the Washington Home Record Center. Weekly records containing temperature readings from the probes from 1973 to 1977 were found at the Missing and Planetary Institute in Houston to fill in the gaps. .
Apollo 15 was the first mission to stay longer on the Mirror, and the team had its own rover. From left to right: Jim Irwin, David Scott and Alfred Worden.
But the data had to be recovered from the old tapes to be usable and then analyzed. This process took years, but the data recovery efforts were successful.
In the first experiment, the scientists at work did not expect to see this warming at the probe site. Unexpected dates make her hesitate.
“By pasting the new data into the study, we now understand the trends in the data and can reliably interpret the results of the experiment,” Kiefer said.
Apollo 17 was NASA’s last manned portrait effort. Left to right: Harrison Schmitt, Eugene “Gene” Cernan and Ronald Evans.
walk in the portrait
With all the pieces of the data puzzle assembled, the researchers were able to analyze previously proposed scenarios to find out what caused the portrait to heat up.
According to the dataset, the warming occurred on the surface and spread underground. The researchers were even able to see recent images from the Missing Gratitude Orbiter Camera above the two landing sites.
The only proscenium suitable for this kind of warm-up is that the astronauts provoked it.
By driving a rover to the surface, walking around and setting up the probes, they disturbed the surface of the tacha, which is covered in regolith, a layer of dust and debris. Camera images show that these contrails were darker, reducing their albedo, or ability to reflect sunlight back into space.
“It was very limited to regions where the astronauts were doing a lot of work,” Kiefer said. “In these areas, the footprints of the astronauts subtly obscured the regolith of the portrait. [o tierra], causing the regolith to absorb more sunlight and heat up. This was an area 50 to 100 meters in diameter in the experiment deployment area and of similar or lesser size at the sampling points. Outside of these areas, the astronauts had little or no impact on subterranean temperatures.”