How water is formed on the Moon India News and Travel Times Provides India-centric and other News and Features

Data from the Moon Mineralogy Mapper (M3), an instrument aboard India's recently ended Chandrayaan-1 spacecraft, along with the Deep Impact spacecraft, has confirmed the existence of water on the surface of the Moon, with scientists explaining the process of its formation. "Water ice on the moon has been something of a holy grail for lunar scientists for a very long time," said Jim Green, director of the Planetary Science Division at NASA Headquarters in Washington. "This surprising finding has come about through the ingenuity, perseverance and international cooperation between NASA and the India Space Research Organization," he added. From its perch in lunar orbit, M3's state-of-the-art spectrometer measured light reflecting off the moon's surface at infrared wavelengths, splitting the spectral colors of the lunar surface into small enough bits to reveal a new level of detail in surface composition. When the M3 science team analyzed data from the instrument, they found the wavelengths of light being absorbed were consistent with the absorption patterns for water molecules and hydroxyl. "For silicate bodies, such features are typically attributed to water and hydroxyl-bearing materials," said Carle Pieters, M3's principal investigator from Brown University. "When we say 'water on the moon,' we are not talking about lakes, oceans or even puddles. Water on the moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the moon's surface," he added. The M3 team found water molecules and hydroxyl at diverse areas of the sunlit region of the moon's surface, but the water signature appeared stronger at the moon's higher latitudes. According to University of Maryland astronomer Jessica Sunshine and co-authors, "The Deep Impact observations of the Moon not only unequivocally confirm the presence of OH/H2O on the lunar surface, but also reveal that the entire lunar surface is hydrated during at least some portions of the lunar day." "Our findings suggest a solar driven cycle in which layers of water only a few molecules thick form, dissipate and reform on the surface each lunar day," she said. "We postulate that hydrogen ions from the Sun are carried by the solar wind to the Moon and there interact with oxygen rich minerals in lunar soil to produce the water (H20) and hydroxyl (OH) molecules that spectral analysis unequivocally show us is there. In a cycle that occurs entirely in daylight, this water is formed in the morning, substantially lost by lunar mid-day, and re-formed as the lunar surface cools towards evening," she added.