Paris: A group of researchers in France found that the inner core of the Moon is a solid ball with a density similar to iron. For long, the scientific world has been wondering about what Moon's inner core is like, whether it is solid or molten, NDTV reported.
The researchers say that the new findings, published in the journal Nature, will aid in more studies in understanding the Moon as well as the Solar system.
The research team, led by astronomer Arthur Briaud of the French National Centre for Scientific Research in France, said that their results question the evolution of the Moon's magnetic field. But it supports a global mantle overturn scenario that brings substantial insights on the timeline of the lunar bombardment in the first billion years of the Solar System, he said.
The team's report says that the seismic data effectively study the inner composition of the objects in the solar system. With how the acoustic waves generated by quakes move through and reflect from the material inside a planet or Moon, scientists could create a detailed map of the object's interior.
Though the team had the seismic data collected by the Apollo mission, its resolution was very low, which reduced the accuracy in determining the inner core's state. The team knew that there was a fluid outside core, but what was inside was debated for a long. Both models of fluid or solid inner core would work with Apollo data, astronomer Arthur Briaud said.
The team collected data from space missions and lunar laser-ranging experiments to compile a profile of various characteristics of the Moon. They matched various core types to find which was closer to the observational data.
According to them, their models that resembled the Moon describe active overturn deep inside the lunar mantle, meaning denser material falls towards the centre and less dense rises upwards.
The Lunar core is pretty similar to Earth's, the team says, with an outer fluid layer and a solid inner core. The outer core is 362 km in radius while the inner is 2358 km. It is around 15% of the radius of the entire Moon. The density of the inner core is 7,822 kilograms per cubic meter, the team said.