The Moon constantly presents the same face in front of the Earth: it is locked by the impact of tide (its period of rotation is equal to period of revolution), and hence a . is dark side, invisible from Earth. Already brought out the difference between the two faces Observation of the face hidden by the Soviet probe Luna 3 in 1959: scientists then discovered a rough and heavily cratered surface (called the highlands) opposite the visible face moon sea – wide field bajalat Deep and smooth in appearance.

Would different chemical compositions explain the lunar asymmetry?

But the elements separating the two lunar faces are not only geomorphological: subsequent missions to Luna 3 also revealed significant differences in the geochemical composition between the two faces. scene side houses a discrepancy chemical structure is called Procellarum Creep Terrain (PKT), characterized by high concentrations of potassium (kinsman rare earth (REE), in Phosphorus (P) as well as other heat generating elements such as thorium (TH). This anomaly is widely represented in and around the K ocean. storm ,Oceanus Procellarum) and is globally found on the visible side, but seems to be heavily scattered on the hidden side.

Scientists currently agree to point the finger at the chemical anomaly PKT to explain the bifurcation between the two lunar faces: characterized by high concentrations of heat-generating elements, this discrepancy induces volcanic processes late in the visible strata. capacity may be. To our satellite. But the mechanism at the root of this discrepancy still remains unknown: presenting even higher concentrations of amorphous elements (which tend to concentrate in phase) liquid when fractional crystallization one of magma), the elements characterized by KREEP would have consequently crystallized eventually, and thus formed the upper layer in a relatively uniform manner moon coat , a new study It seems to have influenced the origin of meteorite formation South Pole-Aitken Basin (the second largest impact basin The Solar SystemThe Moon is located at the south pole, and a small part of which is represented on the visible face – 12 kilometers in depth for 2,500 kilometers in diameter) may preferentially redistribute the elements that make up KREEP at the level of the visible face: in fact In the U.S., the formation of the South Pole–Aitken Basin appears to be tentatively consistent with the formation of the last lunar sea.

A giant meteorite impact may have redistributed chemical elements around the Moon

The team of researchers then produced digital model to simulate the effect of vague On the possible redistribution of heat and KREEP elements produced by such an impact on the Moon’s interior. Their simulations have been shown to be largely conclusive: for any simulated impact scenario (from direct and violent impact to low impact) pace and low angle), the amount of mobilized KREEP elements varies, but is consistently high concentrations of these elements in the distant vicinity, consistent with observed KPT anomalies. Thus, scientists support the idea that a meteorite impact on the origin of the South Pole-Aitken Basin may have made it possible to carry out the excavation. Case in coat upper, lower crust,

And the dating arguments of various lunar formations on the visible side seem to support this idea: the count of craters in the PKT region indicates that this formation would be behind the formation of the South Pole impact basin, and the oldest basaltic sea -4.3 billion. years (about 200 million years after the impact of Aitken); Their model actually shows a thermal asymmetry between the two faces more than 600 million years after the impact, caused by asymmetry in chemical composition and induced volcanic processes on the visible face.