More evidence that the Moon’s core is solid

2023-05-05 16:52:07

MADRID, 5 May. (EUROPA PRESS) –

An analysis of data from various sources used to create descriptive models of the Moon’s interior provides new evidence that Earth’s natural satellite also has a solid core.

In addition to this discovery, a group of researchers also present in Nature magazine evidence that explains the presence of iron-rich materials in the lunar crust.

Although the formation and evolution of the Moon is still up for debate, the nature of its deep interior structure has already been established. More than fifty years after the first space missions to the Moon, there is no longer any doubt: youIt has a solid inner core surrounded by a fluid outer core, like Earth. This hypothesis has now been confirmed thanks to work carried out by scientists from the CNRS, the Université Côte d’Azur, the Côte d’Azur Observatory, the Sorbonne Université and the Paris Observatory-PSL.

Some twenty years after the identification of a fluid outer core, the team has revealed the existence of a solid inner core about 500 km in diameter, which is about 15% of the total size of the Moon. It is made of a metal whose density is close to that of iron. Several methods, related in particular to the rotation of the Moon, had already made it possible to clearly identify the fluid outer core. However, the solid core remained undetectable due to its small size. Its existence has now been proven using data from various space missions and lunar laser range, reports the CNRS.

In addition to this great discovery, several pieces of evidence identified by scientists seem to support the hypothesis of the movement of material within the mantle, the intermediate layer between the core and the crust, during the evolution of the Moon. This is known as lunar mantle rollover and helps explain the presence of iron-rich elements on the Moon’s surface. How was this process carried out? The material could have risen to the surface, producing volcanic rocks that were deposited in the lunar crust. Subsequently, materials that were too dense compared to the surrounding crustal material sank to the core-mantle boundary.

This work provides an important contribution to our understanding of the history of the solar system and of events such as the disappearance of the lunar magnetic field, which was originally one hundred times stronger than Earth’s current one, and now it’s almost non-existent, according to the authors.