posted 06-11-2018 12:53 PM               

Using photos from the extremely high-resolution camera aboard the Lunar Reconnaissance Orbiter (LRO) orbiting the moon, the scientists determined that as astronauts walked or drove on the moon, it disturbed the anorthosite lunar soil — also known as regolith — left over from billions of years of bombardment from space rocks.

That disruption exposed the darker soil, which then absorbed more of the sun's energy and ultimately raised the moon's temperatures...

Over years, that energy propagated downward and deeper into the lunar surface, which is what appeared on the newly acquired data record.

Eventually the temperatures would have reached an equilibrium as absorption stopped, said Kiefer, noting it may have already happened.

posted 06-12-2018 01:47 AM               

This theory gives an explanation to the rise in recorded temp. Without retrieving the equipment and checking the calibration, we assume the equipment was sending true data. So using some basic logic, try to account for the gradual rise in temp in areas that astronauts worked.

The Apollo 15 data shows a cyclic rise and fall of temp that correlates to Earth/Moon journey around the sun. There is no atmosphere or cloud cover to influence the temperature, and the time period of these recordings do not align with recorded solar activity increases, as the sun was in a period of decrease activity from 1971 thru 1977.

Solar hot water systems can raise the temp of water to near boiling point by cycling the water over a black heatsink, heated by the sun, solar ovens can heat food, and the sun can heat black roadways to some very high temps (trust me on this, I live in Australia). So why is it so hard to believe that there may be some merit to this theory?

posted 06-12-2018 12:12 PM               

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.

Their results appear to me to be model based, and while models are an important part of the scientific process, they should be treated as a possible proxy and not as gospel.

For me to buy into this idea, I'd need to see the surface area of all of the tracks measured (or at least approximated), an assessment of the change in reflectivity from the light to the dark soil, the associated response in temperature to these changes, and then an assessment of the influence of the increased temperatures on the entire area that the astronauts explored.

posted 06-12-2018 01:12 PM               

Also, here is a blog entry from the American Geophysical Union about the findings.

The missing tapes and the weekly performance logs gave the researchers enough new information to tease out a likely cause for the mysterious heating. The probes closer to the surface saw a greater temperature jump and saw it sooner than the probes deeper down, suggesting the heat started from the surface and moved downward.

The researchers also paired the new data with images of the Moon's surface from the Lunar Reconnaissance Orbiter. The images show the astronauts' activity disturbed the surface environment at their landing sites, which darkened the lunar soil in those areas. Darker soil absorbs more light from the sun, which makes it warmer, and the researchers suspect this is what caused the warming.

"It doesn't take much disturbance to get that very subtle warming on the surface," Nagihara said. "So analysis of the historic data together with the new images of the Moon really helped us characterize how the surface warmed."

posted 06-12-2018 01:24 PM            

In this case, lacking the ability to carry out a controlled test on the surface of the moon, modelling was used to test the hypothesis.

The limits of model-based testing are well known, but it is obviously appropriate to utilize in this case. The language in the abstracts is appropriate recognition of the limits to the conclusions that can be drawn.

posted 06-12-2018 07:51 PM               

After thinking more about this I am a little more inclined to consider that it is possible that the footprints in the immediate vicinity of the heat flow experiment could be responsible for the observed temp changes (over a small concentrated area).

But I don't think they need to go back to the moon to further their work. Again, estimate changes in reflectivity and surface area affected and do some good old science.

posted 06-13-2018 06:04 AM               

quote:

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Originally posted by MCroft04:
But I'll gladly volunteer to go and collect more data!

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