Asteroids Brought Water on the Moon

Asteroids brought water on the Moon, a new study concludes. Researchers at the British Earth Sciences Department of the Natural History Museum, claim that underground lunar water is the result of an asteroid collision.

The results were delivered by an interdisciplinary team hailing from the US, the UK, and France. The study, entitled “An asteroidal origin for water on the Moon”, was published in Nature Communications journal.

"Asteroids Brought Water to the Moon"

Underground lunar water is the result of an asteroid collision.

Researchers have compared the chemical and isotopic composition of volatiles found on the Moon with volatiles in comets and meteoritic samples of asteroids. Then, the proportion of water that could have been provided by both comets and asteroids populations has been calculated. The results showed that more than 80 percent of the underground lunar water was delivered by asteroids. The water was brought to the Moon when it was still surrounded by a magma ocean. At the time, the Moon was also not shielded by a massive crust that now acts as protection against impacting objects.

The research also states that comets rich on deuterium water have also significantly contributed to the supplies of water on the Moon. More than 20 percent of the Moon’s water, about 4.3 to 4.5 billion years ago, corresponds with the inner Solar System’s water. Similar nature of water is found here, on Earth, too.

Scientists believe that asteroids brought water on the Moon in an event similar to what happened on Earth, when it was hit by an asteroid before the creation of the Moon. Other researchers, however, say that lunar water arrived through comets.

But Dr. Jessica Barnes from the Open University in the UK, author of the study, suggests that comets had little contribution to the underground lunar water. This is because the type of water held in comets, more high on deuterium, is not similar to that found on the Moon, the Earth, or on asteroids.

Authors on the paper concluded that water found on the Moon comes from asteroids and very little of it from comets. Scientists point to asteroids similar to carbonaceous chondrites, which are rocks still found on Earth today. These asteroids are rich in water and organic molecules. It is because of the repeated collisions with these rocks that the Moon is now holding water within its core.