
NASA has revealed that by observing meteoroid strikes, researchers have discovered new concentrations of water on the lunar surface.
Using data collected from the Lunar Atmosphere and Dust Environment Explorer (LADE), researchers from NASA and the Johns Hopkins University Applied Physics Laboratory observed the dispersion of water vapour into the thin lunar atmosphere following meteoroid strikes. It is believed that a thin layer of dry sand covers small concentrations of water across the lunar surface. When a meteoroid strikes the surface the water is dispersed into the atmosphere and quickly dissipates.
“The Moon doesn’t have significant amounts of H2O or OH in its atmosphere most of the time,” said Richard Elphic, the LADEE project scientist at NASA’s Ames Research Center. “But when the Moon passed through one of these meteoroid streams, enough vapor was ejected for us to detect it. And then, when the event was over, the H2O or OH went away.”
According to researchers, a meteoroid had to penetrate at least 8 centimetres (3 inches) below the lunar surface to release water. This layer was followed by a thin transition later and then a hydrated layer. In the hydrated layer, water molecules likely stick to bits of soil and rock called regolith.
The contraction of water in these hydrated layers has been calculated to be approximately 200 to 500 parts per million. To put that in context, one would need to process more than a metric ton of soil to collect just 500 millilitres (16 ounces) of water or more simply, the soil is significantly drier than the driest soil on Earth.
Although not an answer to offering drinking water to long-term crewed missions to the Moon, the discovery will help researchers understand the Moon’s geologic past and its continued evolution.