Careful examination revealed that the inner core of the Moon is actually a solid ball with a density similar to that of iron. Researchers hope this will help resolve the longstanding debate about whether the interior of the Moon is solid or molten, and will lead to a more accurate understanding of the history of the Moon and thus the Solar System.

“Our results question the evolution of the Moon’s magnetic field and confirm a spherical mantle, proving the existence of an inner core,” writes the team, led by astronomer Arthur Briot of the French National Scientific Research Center in France. inversion.” A scenario that provides important insights into the chronology of lunar bombardment in the first billion years of the solar system.”

Drilling of the internal composition of objects in the Solar System is most effectively accomplished using seismic data. How acoustic waves created by earthquakes pass through and bounce off matter inside a planet or moon can help scientists build a detailed map of the object’s interior.

We have lunar seismic data collected by the Apollo missions, but the resolution is too low to accurately determine the state of the inner core. We know it’s a fluid outer core, but what that entails remains a matter of debate. The solid inner core and all liquid core models perform equally well with the Apollo data.

To find out for sure, Brio and colleagues compiled data from space missions and lunar laser range experiments to profile various features of the moon. These include the degree of deformation due to gravitational interaction with the Earth, the change in distance from Earth, and its density.

They then ran simulations with different kernel types to find the best match with the observational data.

They made some interesting discoveries. First, the models most similar to what we know about the Moon describe active tipping deep within the lunar mantle. This means that the denser material inside the Moon falls towards its centre, while the less dense material rises. This activity has long been proposed as a way to explain the presence of certain elements in the volcanic regions of the Moon. The team’s research adds one more point to the evidence count.

And they found that the Moon’s core is very similar to Earth’s, with a liquid outer layer and a solid inner core. According to their simulations, the diameter of the outer core is about 362 kilometers, and the diameter of the inner core is about 258 kilometers. That’s about 15 percent of the Moon’s entire radius.

The team found that the inner core also has a density of about 7,822 kilograms per cubic metre. This is very close to the density of iron.

Interestingly, in 2011 a team led by NASA Marshall planetary scientist Renee Weber found a similar result using the most advanced seismological methods of the time based on Apollo data to study the lunar core. They found evidence of a solid inner core with a radius of about 240 kilometers and a density of about 8,000 kilograms per cubic metre.

Brio and his team say their results confirm these previous findings and provide strong evidence for an Earth-like lunar core. And this has some interesting implications for the evolution of the Moon.

We know that the Moon, which began to weaken about 3.2 billion years ago, had a strong magnetic field shortly after its formation. Such a magnetic field is created by motion and convection in the core, so what the lunar core is made of is closely related to how and why the magnetic field disappears.

Given humanity’s hope of returning to the moon relatively soon, we may not have to wait long for seismic confirmation of these findings. Study published Nature.