With cutting-edge equipment, Chinese scientists are studying the far side of the satellite in an unprecedented way. New data give clues about the formation of the lunar subsurface.
After spending a year analyzing the Von Kármán crater, the Chinese Chang’E-4 mission rover brings news about the far side of the Moon.
In an article published in Science Advances, Chinese astronomers shared new information about the subsoil in the region – which is quite different from other areas already explored in previous missions.
“We found that the signal penetration [of radio waves] at the [landing site] of the EC-4 is much greater than that measured by the previous spacecraft, Chang’E-3, at the nearest landing site,” says Li Chunlai, article co-author and director-general of the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC), in a note.
According to the researcher, the first observations suggest that the terrain has a geological configuration very different from other regions of the Moon.
How the work is being done
With a “much more transparent” subsurface on its far side, researchers can analyze in more detail what is below the surface of the Moon.
Thus, the Yutu-2 rover, equipped with a Lunar Penetrating Radar, can send radio signals with a frequency of 500 MHz to a depth of 40 meters, three times more than that achieved during the CE-3 mission.
Despite the good quality of the radar image along the route of the rover, at a distance of about 106 meters, the complexity of the spatial distribution and the shape of the radar characteristics makes it very difficult to identify the geological structures and events that generated these characteristics “said Su Yan, another author of the article, who is also affiliated with NAOC.
Even so, the researchers are making great strides in terms of satellite stratigraphy, that is, in expanding their knowledge about the layers of their subsoil.
We learned a lot about the Moon
Highly porous granular materials that have been incorporated into rocks of different sizes: this is the lunar subsurface composition, according to the combination of radar images with tomographic data from the subsoil.
The formation probably goes back to the days when the satellite was frequently hit by meteors and other space debris. The impact of these collisions formed a surface full of craters and a subsoil with varying layers.
“The results illustrate, in an unprecedented way, the spatial distribution of the different products that contribute to the sequence of ejects [impacts] and their geometric characteristics”, says Li, referring to the wreckage left by each impact on the satellite, which formed its subsoil.
For the researcher, in addition to discovering more details about the geological evolution of the Moon, the technology used in the mission may also reveal news about the extinct volcanoes in the region and the history of collisions and impacts on the satellite.