In some areas, the lunar surface is covered with "vortices" - light wavy patterns that stand out clearly against the background of the surrounding area. For a long time, their origin remained a mystery. But thanks to the data collected by ARTEMIS probes, scientists have finally received an answer to the question of the mechanism for the formation of these patterns. A team of researchers from the Space Flight Center. Goddard concluded that they were formed as a result of the interaction of the solar wind and magnetized areas of the lunar surface.
Reiner Gamma structure. Source: NASA LRO WAC science team.
Light patterns on the surface of the Sea of Dreams. Source: NASA.
Light patterns on the surface of the Sea of Dreams. Source: NASA / GSFC / Arizona State University.
Light patterns in the area of the Firsov crater. Source: NASA.
The sun emits a continuous stream of charged particles (mostly protons) that extend far beyond Pluto's orbit. Our planet is largely protected from it by the global magnetic field deflecting and trapping these particles. As you know, unlike the Earth, the Moon does not have its own magnetosphere. However, this was not always the case. Analysis of lunar rock samples delivered to ground laboratories showed that they were formed in a strong magnetic field.
This indicates that in the distant past (about 4 billion years ago) in the bowels of our natural satellite the mechanism of the "planetary dynamo" was operating. The movement of streams of liquid matter in the lunar core led to the formation of a constant magnetic field. However, due to its small size, the Moon could not support this process for a long time. At some point, her bowels hardened, and she lost her magnetosphere.
Promotional video:
Since that time, magnetized areas have remained on the lunar surface. The results of observations carried out by the ARTEMIS satellites indicate that they can create local magnetic "shields" ranging from hundreds of meters to hundreds of kilometers. Such "screens" deflect some of the charged particles of the solar wind. Therefore, the regolith in the “protected” areas has a lighter shade than the surrounding surface. Scientists figuratively compare this mechanism with "sunscreen".
Scheme of action of protective screens created by magnetized lunar rocks. Source: NASA's Goddard Space Flight Center.
Unfortunately, such magnetic "shields" will not be able to protect people from the effects of cosmic radiation. However, studying them will help engineers develop new technologies to better protect future explorers and lunar inhabitants.