NASA spots water molecules in Moon
- Scientists, using NASA’s Lunar Reconnaissance Orbiter (LRO), have observed water molecules moving around the dayside of the moon, the U.S. space agency said, an advance that could help to learn about accessibility of water that can be used by humans in future lunar missions.
Lyman Alpha Mapping Project (LAMP)
- Measurements from the Lyman Alpha Mapping Project (LAMP) instrument aboard the LRO of the sparse layer of molecules temporarily stuck to the surface helped characterise lunar hydration changes over the course of a day, according to the study.
- Up until the last decade, scientists thought the Moon was arid, with any water existing mainly as pockets of ice in permanently shaded craters near the poles.
- More recently, scientists have identified surface water in sparse populations of molecules bound to the lunar soil. The amount varies based on the time of day.
- This water is more common at higher latitudes and tends to hop around as the surface heats up.
- These results aid in understanding the lunar water cycle and will ultimately help us learn about accessibility of water that can be used by humans in future missions to the Moon, a senior scientist at the Planetary Science Institute.
- Lunar water can potentially be used by humans to make fuel or to use for radiation shielding or thermal management; if these materials do not need to be launched from Earth, that makes these future missions more affordable.
- Water molecules remain tightly bound to the regolith until surface temperatures peak near lunar noon.
Evidence of water
Notably, Chandrayaan-1’s data helped determine the presence of water ice on the moon, which NASA announced in September 2009. The agency’s Moon Mineralogy Mapper detected evidence of a hydrogen-oxygen chemical bond (hinting at water or hydroxyl) when looking at the top area of the moon’s regolith (soil). The signal of water appeared to be stronger at the poles. After NASA’s announcement, ISRO said its Moon Impact Probe had also detected the signature of water on the moon, just before it impacted the surface.
The water signal was confirmed by other spacecraft observations. The Cassini spacecraft spotted the water/hydroxyl signal in 1999 while passing by the moon on its way to Saturn. And the Deep Impact spacecraft’s extended EPOXI mission examined the moon in infrared wavelengths (after a request from the M3 team). Deep Impact/EPOXI found the signal while making several flybys of the moon and Earth on its way to comet 103P/Hartley 2.
Follow-up observations by NASA’s LCROSS (Lunar CRater Observation and Sensing Satellite) found more water at the moon’s south pole, NASA announced in November 2009. This and other observations of water ice by the Lunar Reconnaissance Orbiter (LRO) in the years since have led some engineers to speculate that future explorers could use the reservoirs for lunar colonies, depending on how much water is available.
In March 2017, researchers located Chandrayaan-1 in a polar orbit that was about 200 kilometers (125 miles) above the lunar surface. The spacecraft’s orbit was about 180 degrees or half a cycle from orbital estimates in 2009. The team found the spacecraft using radar from NASA’s Goldstone Deep Space Communications Complex, with some follow-up work from the Arecibo Observatory in Puerto Rico.