The presence of a partially molten layer between the rocky mantle and the moon's solid metallic core seems most likely after studying the change in its shape and gravity.

Researchers at NASA's Goddard Space Flight Center and the University of Arizona analyzed new data describing the asteroid The solidity of the Moon under the influence of the gravity of the Earth and the SunHe concluded that its mass was unlikely to be completely solid.

Instead, the Moon's mantle contains a thick, sticky region that rises and falls like our tides.

“Modeling of the Moon's interior suggests that these values ​​can only be matched by a low-viscosity region at the base of the lunar mantle,” the researchers wrote in the article. published in Provided by the Arabian Gulf University.

Researchers proposed the idea of ​​this non-rigid layer several decades ago, but until now the available data have not made it possible to effectively determine whether this layer actually exists.

Under the influence of the gravity of the Earth and the Sun, The moon experiences tidal influence – Not in terms of oceans, but in terms of physical deformations of the moon's surface and gravitational field.

For this study, The team used new readings implemented before Gravity recovery and indoor laboratory From NASA and Lunar reconnaissance vehicle.

These measurements allowed the researchers Estimating, for the first time, lunar tidal changes on an annual basis.

Computer models describing the nature of the rocks inside the Moon as it orbits Earth suggest that the layer beneath the solid mantle would have to be at least somewhat sticky for the numbers to fit.

Like him, Other questions are askedWhich are: How did this area end up there? And what keeps it warm? More research will be needed to know for sure, but the team behind this study believes Iron oxide minerals and titanium ilmenite may be involved.

“The presence of a low-viscosity zone at the lower base of the lunar mantle can be easily explained by partial melting of an ilmenite-rich layer, What makes the moon similar to marsPartial melting was recently inferred from seismic data analysis.

According to Science AlertAs with Earth studies, some guesswork is required to assess what's hundreds and thousands of miles below the surface — but it's all very educated guesswork, based on what we know about moons and planets.

It is known that the mantle above the low-viscosity zone is largely composed of metal Olivinewhich has a story to tell over several billion years.

If we can establish a permanent base on the Moon in the next few yearsSeismic readings Experiments on the Moon's surface in and of themselves should be able to tell us more about what's going on beneath the surface.

“The existence of this area Profound effects on thermal status The researchers concluded.