NASA's SOFIA Finds Water On The Moon's Sunlit Side!


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The Clavius Crater on the Moon as seen by NASA's Lunar Reconnaissance Orbiter. The SOFIA observatory has detected water ice in shadowed regions of this sunlit lunar location ((Image credit: NASA/Moon Trek/USGS/LRO)

The presence of ice in the permanently shadowed craters around the Moon's poles has been known for some time. However, researchers had been unsure if the hydration detected on the satellite's sunlit areas was "molecular" water (H2O), or hydroxyl (OH), a molecule that's one hydrogen atom shy of becoming water. On October 26, 2020, NASA confirmed that the liquid was indeed water.

“We had indications that H2O – the familiar water we know – might be present on the sunlit side of the Moon,” said Paul Hertz, Director of Astrophysics at NASA. “Now we know it is there. This discovery challenges our understanding of the lunar surface and raises intriguing questions about resources relevant for deep space exploration.”

The discovery was made using data collected by NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA). The modified Boeing 747 aircraft, which can fly its large telescope at altitudes of up to 45,000 feet, allows researchers to clearly observe space objects. The water molecules — detected using a special infrared camera capable of discerning between the wavelengths of H2O and OH — were found in the Clavius Crater. Located on the Moon's Southern Hemisphere, the large crater can be clearly seen from Earth.

The Moon’s Clavius Crater, with an illustration depicting water trapped in the lunar soil there, along with an image of NASA’s SOFIA, which found lunar water. (Credit: NASA/ Daniel Rutter)

However, before you start packing your bags for our satellite, be warned that the water concentration is extremely low — about 100 to 412 parts per million. To put it in perspective, the Sahara Desert has about 100 times more water! "This is not puddles of water but instead water molecules that are so spread apart that they do not form ice or liquid water," said NASA researcher Casey Honniball, who led the study. Though not enough to sustain humans, the discovery is significant because water is a rare and precious resource in deep space.

The scientists speculate that the H2O molecules may have been deposited by the tiny meteorites that are continually bombarding the Moon's surface. Another plausible explanation involves a multi-step process where the Sun's solar wind brings hydrogen to the Moon, which then reacts with oxygen-bearing minerals in the soil to create hydroxyl. This hydroxyl could later be transformed into water from the micrometeorites' radiation.

The Clavius Crater is one of the Moon's largest craters and visible from Earth (Jstuby/ CC0,/ Wikimedia Commons)

Also perplexing is how the water escapes evaporation. The liquid could be trapped in tiny bead-like structures in the soil that form from the intense heat generated from the micrometeorite impacts. Alternatively, the H2O molecules may be hidden inside the lunar soil grains and sheltered from the Sun.

“Without a thick atmosphere, water on the sunlit lunar surface should just be lost to space,” said Honniball. “Yet somehow we’re seeing it. Something is generating the water, and something must be trapping it there.”

NASA plans to conduct follow-up missions to determine how widespread the water is across the lunar surface. The findings will allow the US space agency to find the perfect landing for its Artemis mission that will take the first woman and next man to explore the Moon more extensively in 2024.


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  • eternalicedrake
    eternalicedrakeTuesday, December 22, 2020 at 5:49 am
    I wonder if this means that at one point a species of animal, such as tardigrades that can live in space, once lived on the moon.
    • legitbg
      legitbgFriday, December 11, 2020 at 8:13 am
      maybe if they could find water people can live on the moon
      • awalker_05
        awalker_05Monday, January 11, 2021 at 12:33 pm
        If you read the article-it says that the water cant sustain humans
        • babyyodaforever
          babyyodaforeverWednesday, January 27, 2021 at 5:01 pm
          That could change once we find more water.
        • cats_no_science
          cats_no_scienceWednesday, December 23, 2020 at 9:43 am
          Actually, it is more possible to someday live on mars then the moon. Although, it could still take hundreds of years.
          • babyyodaforever
            babyyodaforeverWednesday, January 27, 2021 at 5:02 pm
            Mars is WAY too hot.
            • g-rat
              g-ratTuesday, February 23, 2021 at 9:01 am
              I like your observations and how your saying mars is too hot and its good to be skeptical of things but mars isnt actually that hot taking into consideration everything Mars is the 4th planet and earth is the 3rd while that doesnt seem like it would make a difference theres so much space in between the planets, and the moon orbits the earth meaning at some points the moon is closer to the sun than even the earth which also means its even more closer than before to the sun than mars.
        • potato346
          potato346Thursday, December 10, 2020 at 11:17 am
          it's so cool how there could be water on the moon.
          • maria_goodvibes
            maria_goodvibesTuesday, December 8, 2020 at 11:56 am
            This is cool but how does the water get on the moon?
            • g-love
              g-loveTuesday, December 8, 2020 at 10:58 am
              How are you supposed to find water on the moon that is so crazy!
              • bruhwhyyou
                bruhwhyyouTuesday, December 8, 2020 at 9:36 am
                how do the telescopes zoom in that much on the moon that you can see the molecules from that far away
                • bruhwhyyou
                  bruhwhyyouTuesday, December 8, 2020 at 9:34 am
                  if the H2O on the moon is so small that it cant even make ice or liquid water then it has to be a gas but its staying there and not moving which is crazy
                  • bruhwhyyou
                    bruhwhyyouTuesday, December 8, 2020 at 9:32 am
                    what could be generating the water on the moon is it the moon's core and how is the water not floating off in space because of the moons small atmosphere
                    • k1ng_snd
                      k1ng_sndTuesday, December 8, 2020 at 5:57 am
                      how would water get on the moon?????
                      • dimondlove
                        dimondloveSunday, December 6, 2020 at 5:01 pm
                        wow this is so cool