Abundant evidence of iron and titanium oxides below the surface of the Moon has been detected by NASA’s Lunar Reconnaissance Orbiter (LRO), the first satellite of the “Vision for Space Exploration”, NASA program whose ultimate goal is to sending astronauts to the Moon, establishing permanent bases on its surface and achieving the first manned flight to Mars.
LRO and metal
The LRO results are a small step to better understand how the moon formed, as the observations show how iron and titanium oxides are distributed beneath the Moon’s northern hemisphere .
The new research is based on a device called a miniature radio frequency (Mini-RF) instrument , a radar probe designed to map lunar geology, search for water ice and test communications technologies.
The instrument scoured the terrain in the northern hemisphere of the moon in search of an electrical property called the dielectric constant. This constant is a number that compares the ability of a material to transmit electric fields with that of the vacuum of space.
Electric field transmission is useful for finding ice in the shadows of craters, where it is protected from the sun’s heat. But it can also identify areas with more metals, such as iron and titanium oxides .
And the scientists noticed that the dielectric constant increased with the size of the crater, but only up to a point. The team’s theory was that the first few hundred thousand feet of the moon’s surface have few of these oxides, but a richer source of the metal is found further down. Then, as the meteorites collide with the lunar surface and scratch the upper layers, the metals are exposed . That kind of pattern would also explain the low levels of metals in the lunar highlands and the higher abundances in the darker, lower plains closer to the moon’s subsoil.
The results are even more intriguing in light of a puzzling phenomenon reported in 2019 by NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission on the Moon. Gravity measurements from the Moon suggest that there is a large amount of dense material found tens to hundreds of kilometers below the massive South Pole-Aitken basin of the moon. The GRAIL results, along with the new LRO finding, suggest that metals may be more concentrated in certain regions of the moon .