Water In Ancient Moon Rocks May Have Proto-Earth Origin

Researchers of a new study have found evidence that suggests the water found in ancient Moon rocks may have come from proto-Earth, surviving moon-forming events.

Previous studies suggested that the water discovered on the moon was from a comet. But a new study has found that the water in ancient moon rocks could actually belong to Earth. Water was already present on Earth. When Earth experienced an explosion 4.5 billion years ago that created a moon, scientists believe some pieces from Earth may have fallen on the moon, which may have contained water.

Earlier studies also found that the lunar surface might be a lot wetter than previously believed during the Apollo era. Hence, researchers from the Open University, UK, conducted a study to determine the amount of water present in the mineral apatite, a calcium phosphate mineral found in samples of the ancient lunar crust.

"These are some of the oldest rocks we have from the Moon and are much older than the oldest rocks found on Earth. The antiquity of these rocks make them the most appropriate samples for trying to understand the water content of the Moon soon after it formed about 4.5 billion years ago and for unraveling where in the Solar System that water came from," lead author Jessica Barnes explained in a press release.

Findings of the study also revealed that ancient moon rocks contained significant amounts of water locked within their crystal structure. To identify the source of this water, researchers of the study measured the hydrogen isotopic signature of the water.

 "The water locked into the mineral apatite in the Moon rocks studied has an isotopic signature very similar to that of the Earth and some carbonaceous chondrite meteorites," said Barnes. "The remarkable consistency between the hydrogen composition of lunar samples and water-reservoirs of the Earth strongly suggests that there is a common origin for water in the Earth-Moon system."

Earlier in August, researchers from Johns Hopkins University Applied Physics Laboratory used data from NASA's instrument aboard the Indian spacecraft Chandrayaan-1 and discovered the presence of mineral-rich, magmatic water (water that originates from deep within the Moon's interior) on the lunar surface.