Lunar mystery solved by recovery of lost Apollo mission tapes

Summary: "raw data on the temperature of the moon's surface, as well as a few meters below it, was transmitted from the probes and recorded on magnetic tapes". Some of the tapes were not correctly archived and were only recently found. The previously available tapes showed that "the moon unexpectedly rose in temperature by 1.8°F to 3.6°F near the probes. The possible reasons for this change were debated by planetary scientists for decades." Now with the new data, and because "researchers were also able to look at recently acquired images from the Lunar Reconnaissance Orbiter Camera over the two landing sites, [t]he only scenario that fits this type of warming is that the astronauts caused it. While they were driving[/walking] over the surface, [they] disturbed the moon's surface, which is covered in regolith, a layer of dust and debris. Images from the camera show that those paths were darker, which lowered their albedo, or ability to reflect the sun's light into space", thereby absorbing more heat.

Here's the paper ...

Examination of the Long‐Term Subsurface Warming Observed at the Apollo 15 and 17 Sites Utilizing the Newly Restored Heat Flow Experiment Data From 1975 to 1977

> The Apollo heat flow experiment (HFE) was conducted at landing sites 15 and 17. On Apollo 15, surface and subsurface temperatures were monitored from July 1971 to January 1977. On Apollo 17, monitoring took place from December 1972 to September 1977. The investigators involved in the HFE examined and archived only data from the time of deployment to December 1974. The present authors recovered and restored major portions of the previously unarchived HFE data from January 1975 through September 1977. The HFE investigators noted that temperature of the regolith well below the reach of insolation cycles (~1 m) rose gradually through December 1974 at both sites. The restored data showed that the subsurface warming continued until the end of observations in 1977. Simultaneously, the thermal gradient decreased, because the warming was more pronounced at shallower depths. The present study has examined potential causes for the warming. Recently acquired images of the Lunar Reconnaissance Orbiter Camera over the two landing sites show that the regolith on the paths of the astronauts turned darker, lowering the albedo. 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. 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 K at the time of probe deployment best duplicates the magnitude and the timing of the observed subsurface warmings at both Apollo sites.

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018...

Anthropogenic Lunar Warming!

(Humans are the worst...)

I thought it was talking about these missing tapes: https://en.wikipedia.org/wiki/Apollo_11_missing_tapes. That would have been amazing.

This is the experiment in question, for those curious: https://www.lpi.usra.edu/lunar/missions/apollo/apollo_17/exp...

The article outlines some of the details as well, but it was lacking in depth, which can be found in the experiment results and details links in the page above.

Does anyone know how effectively block that annoying video?

No. No need to loop around for 80 years. NO. Seriously. No way. STFU

How do tapes like this get lost in the first place? I mean, if you were a startup funding this mission, and your CTO said, “Oops! I totally lost all that data from our multibillion dollar mission!” wouldn’t you fire them immediately?