Presently we have very less information regarding the type of minerals that might be found inside the Moon. But a group of researchers from Canada and the US has used this hint to understand that a treasure is lying beneath the surface.
By getting more information about the chemistry of the moon, scientists would be able to settle a confusion regarding the apparent lack of precious elements constituting the mantle of Moon. Nearly fifty years ago, astronauts brought back a large quantity of lunar material which gave the first hints about the elements that might be present below the surface. James Brenan, Earth scientist from Dalhousie University, Canada said that nearly 400 kilograms of the sample was brought in the Apollo and lunar missions. So to find about the Moon’s interior, scientists have to go through reverse-engineering of the composition of lavas on the surface.
Through retro-engineering the basalts which were brought from the Apollo 15 and 17 missions, researchers estimated the amount of siderophile elements which make up the mantle of Moon. Some of these might have come from the rain of leftover materials in the finishing stages of the Solar System’s construction, so it can tell the assault endured by the Moon after its formation was complete. The work appears in Nature Geoscience journal.
The measurements were lower by 10 to 100 times than what was expected. Even by adjusting the model to accommodate the event of erosion of Moon by the meteorites, the numbers did not add up which left a plethora of questions. Researchers often begin by assuming the geochemistry of Moon to be similar to Earth and this is where the gaps in the measurement start. Although several theories suggest that Moon was made from Earth’s components there are some notable differences.
Hence researchers used the experiment results on sulfur solubility with the models on pressure and the thermodynamics of magma cooling down to get accurate constraints on the composition of the lunar mantle. Brenan said that the results tell that sulfur in the volcanic rocks of Moon indicates the presence of iron sulfide in the Moon’s rocky interior. This is the place where the metals might have been during the formation of lavas.
The results make it clear that we cannot depend on the existing rock samples for any clear conclusion as no accurate estimation of metal composition cannot be found. Whether it would be justified for mining these metals would depend on future missions and economics. But this makes the return to Moon quite exciting.