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July 5th, 2023
Moon as observed from the International Space Station.
Image credit: NASA
What is going on with Compton-Belkovich?
This feature on the Moon, a suspected volcano, is indeed glowing at microwave wavelengths.
A new instrument type has discovered evidence of a volcanic process on the Moon that had only been seen on Earth, reports Matthew Siegler, Senior Scientist at the Planetary Science Institute (PSI) and lead author of “Remote Detection of a Lunar Granitic Batholith at Compton-Belkovich” that appears in the journal Nature.
Using data from both China’s Chang’e-1 (2007) and Chang’e-2 (2010) lunar orbiters, researchers have been able to map temperatures below the Moon’s surface.
Image credit: Matthew Siegler, PSI.
As noted in the paper, “the surprising magnitude and geographic extent of this feature imply an Earth-like, evolved granitic system larger than believed possible on the Moon, especially outside of the Procellarum region” on the Moon.
Extra heat
“What we found was that one of these suspected volcanoes, known as Compton-Belkovich, was absolutely glowing at microwave wavelengths,” Siegler said in a PSI statement. “What this means is that it is hot, not necessarily at the surface, as you would see in infrared, but under the surface.”
Siegler added that the only way to explain this glow is from extra heat coming from somewhere below the feature within the deeper lunar crust.
“So Compton-Belkovich, thought to be a volcano, is also hiding a large heat source below it,” Siegler said.
On the Moon, a granitic batholith is a huge body larger than 20 kilometers of what was once subsurface lava that never erupted.
China’s Chang’e-1 Moon orbiter. Image credit: CNSA via NASA/NSSDCA
Unique data set
Tucson, Arizona-based PSI’s Jianqing Feng is a co-lead author, along with other research colleagues.
Making use of an instrument looking at microwave wavelengths – longer than infrared – sent to the Moon on both the Chinese orbiters — enabled the mapping of temperatures below the lunar surface.
“It was a neat project in that China made their data public – as does NASA – and we were able to work with this unique data set to figure out something really interesting about the Moon,” Siegler noted.
Image taken by the NASA Lunar Reconnaissance Orbiter’s LROC image system. A small portion of the Compton-Belkovich Volcanic Complex. The upper two thirds of the scene shows the volcanic complex, whereas the lower third of the image is outside of the complex. The terrain outside of the complex exhibits a greater abundance of impact craters than inside the complex. Image credit: NASA/GSFC/Arizona State University
Science and politics
Following the rules, there was not direct collaboration with Chinese researchers. All funding for the project came only from NASA, “so we had to follow the breadcrumbs to crack this dataset open” Siegler said.
“Jianqing’s ability to come to the U.S. through the J visa system to navigate the data and existing literature on the topic was very valuable,” Siegler pointed out. “It is a great example of what can be done if science and politics can work together.”
Siegler’s and Feng’s work on the project was funded by a grant to PSI from NASA’s Lunar Data Analysis program and Lunar Reconnaissance Orbiter mission.
To gain access to the Nature published research – “Remote detection of a lunar granitic batholith at Compton–Belkovich” – go to:
Posted in Space News
