A lunar meteorite found in northwest Africa contains a mineral that can form only in the presence of water, strengthening the case for the existence of water on the Moon.
One of 13 meteorites studied by a team of Japanese researchers led by Masahiro Kayama of Tohoku University‘s Frontier Research Institute for Interdisciplinary Sciences contains moganite, a mineral that requires water to form.
All of the meteorites, which had been found in a hot African desert, were analyzed to identify their chemical compositions and their minerals’ structures.
“Moganite is a crystal of silicon dioxide and is similar to quartz. It forms on Earth as a precipitate when alkaline water including SiO2 [silicon dioxide] is evaporated under high pressure conditions. The existence of moganite strongly implies that there is water activity on the Moon,” Kayama said.
The fact that just one of the 13 meteorites contains moganite indicates the mineral did not form on Earth after the meteorite’s impact.
“If terrestrial weathering had produced moganite in the lunar meteorite, there should be moganite present in all the samples that fell to Earth around the same time. But this was not the case,” Kayama noted.
This is the first ever detection of moganite in a lunar meteorite. The researchers believe the meteorite came from a region on the Moon known as Procellarum Terrane and formed when sunlight caused water beneath the Moon’s surface to evaporate.
Kayama believes this could indicate water ice is present in the Moon’s subsurface at middle and lower latitudes. So far, the only evidence for water on the Moon has been found at the lunar poles, where small pockets of cold traps are created by a narrow angle of sunlight.
If water ice is present in the lunar subsurface, it could be used by future astronauts for everything from drinking water to rocket fuel and would increase the chances of building a long term lunar settlement.
A paper on the team’s findings has been published in the journal Science Advances.