The Apollo 11 space mission in July 1969 was the first manned mission to reach the lunar surface and its astronauts stepped over it, and the additional objectives of the flight included scientific exploration by the crew of the lunar module, the deployment of a television camera to transmit signals to Earth, the deployment of the solar wind formation experiment, earthquake intensity measuring devices, and a laser reflector to determine the distance between the Earth and the Moon, and the astronauts had to bring samples of lunar surface materials and take many pictures of the lunar terrain.
Since then, there have been studies and scientific research aimed at exploring the internal and external structure of the moon, its topography, the formation of its crust, the minerals and materials contained in its soil, and the question of whether the core of the moon is solid - like the earth - or a liquid has been repeated, which is one of the questions that would lead us to a more accurate understanding of the history of the moon, and then the history of the solar system.
Now, 50 years after Apollo 11 paved the way for the first surveys of the moon, a team of scientists from the French National Center for Scientific Research (CNRS), and other French universities and observatories, have shed light on part of the moon's internal structure that has so far remained a mystery, and they have found that the moon has a solid core like Earth, in addition to providing evidence explaining the presence of iron-rich substances in the lunar crust. On the third of May.
Studies have continued to explore the structure of the moon, its topography, the composition of its crust, and the minerals and substances contained in its soil (Getty Images)
Solid inner core
The press release published by the official website of the French National Center for Scientific Research states that after about 20 years of confirming the existence of a liquid outer core for the moon, the team has now detected the existence of a solid inner core with a diameter of about 500 km, which represents about 15% of the total volume of the moon, and is made up of a metal whose density is close to the iron density of about 8,<> kilograms per cubic meter.
Previously, different methods – particularly related to the rotation of the Moon – had already made it possible to clearly identify the fluid outer core, but the solid core remained undetectable due to its small size, until its existence has now been proven using data from different space missions and using the lunar laser field (an ongoing experiment that measures the distance between Earth and the Moon using a laser range).
A team at NASA in 2011 reached a similar conclusion using modern seismic techniques, and found evidence of a solid inner core with a radius of about 240 kilometers, and a density of about 8,<> kilograms per cubic meter.
Various methods previously related specifically to the rotation of the Moon made it possible to determine the fluid outer core of the Moon (NASA)
Scarf coup
In addition, the press release states that many of the evidence identified by scientists supports the hypothesis that material moved inside the mantle (i.e., the middle layer between the core and crust) during the moon's evolution, known as mantle inversion, and helps explain the presence of iron-rich elements on the moon.
Scientists hypothesize that these materials could have risen to the surface, producing volcanic rocks deposited in the lunar crust, and later sank material that was so dense compared to the surrounding crust material back to the core and mantle boundary.
Overall, this work makes an important contribution to our understanding of the history of the solar system and certain events, such as the disappearance of the Moon's magnetic field, which was originally 100 times stronger than Earth's field today and now almost non-existent.