US: NASA-funded scientists estimate from recent research that the volume of water molecules locked inside minerals in the moon’s interior could exceed the amount of water in the Great Lakes here on Earth.
Previous studies found evidence of water both on the lunar surface and inside the moon by using respectively, remote sensing data from the Indian spacecraft Chandrayaan-1 and other lunar sample analysis. Carnegie researchers looked within crystalline rocks called KREEP (K for potassium; REE, for rare Earth elements; and P for phosphorus). These rocks are a component of some lunar impact melt and basaltic rocks.
“Since water is insoluble in the main silicates that crystallised, we believed that it should have concentrated in those rocks,” said Andrew Steele of Carnegie and co-author of the report. “That’s why we selected KREEP to analyse.”
The identification of water from multiple types of lunar rocks that display a range of incompatible trace element signatures indicates that water may be at low concentrations but ubiquitous within the moon’s interior, potentially as early as the time of lunar formation and magma ocean crystallisation.
Bradley Jolliff, lunar scientist of Washington University in St. Louis, said, “The concentrations are very low and accordingly, they have been until recently nearly impossible to detect. We can now finally begin to consider the implications – and the origin – of water in the interior of the moon.”
The research was funded by the NASA Astrobiology, Mars Fundamental Research, and the Lunar Advanced Science and Exploration Research programs in NASA’s Planetary Division in Washington.