Data from a lunar orbiter recently gave way to the conclusion that the moon has been wet for billions of years. It was initially thought that the moon was bone dry and this is according to samples of lunar soil brought back by the Apollo astronauts. In the last ten years, there had been several lunar missions that have found water deposits on the moon, several signs of frozen surface water isolated in the moon's freezing dark craters.
A few days ago, the plan to mine the moon for water was expressed by the Australian Space Agency (ASA) but the main challenge was to identify where exactly on the moon are they supposed to do so.
"We knew there was water in the soil," Benna says. "What we didn't know was how widespread that water was, or how long it had been there."
Benna and her colleagues recently used data captured by NASA's LADEE (Lunar Atmosphere and Dust Environment Explorer) spacecraft, which orbited the moon from November 2013 to April 2014. LADEE's spectrometers detected dozens of sharp increases in the abundance of water molecules in the moon's exosphere, mainly indicative of the existence of a water cycle. It also showed meteorites striking the moon's surface, directly stirring up lunar soil showing hydrated soil beneath.
They further calculated that only meteorites heavier than about 0.15 grams could have released the water from the surface. That means that the top couple of centimeters of lunar soil are indeed dry since smaller impacts would have released water if there was any.
This does not mean though that the moon is abundant with water, not even close. According to Benna, "Squeezing half a ton of lunar soil would yield barely a small bottle of water. It's not a lot of water by any measure, but it's still water."
There was some speculation about the findings but the presence of water below the moon's surface according to planetary scientist Erik Asphaug of the University of Arizona in Tucson is "plausible and certainly provocative".
One would then wonder, why such a small amount of water would excite scientists this much. Well, for one, several studies have shown that water from the moon was said to possibly have the capacity to fuel rockets. This is especially helpful for manned space missions. his could be just one of the many uses of moon water; the possibilities are endless. Future researches could help investigate whether and how that water could be useful for human explorers.
