Water on sunlit area of Moon

There is water on the sunlit surface of the Moon, Nasa has announced. The discovery suggests water may be distributed across the lunar surface and not just limited to cold, shadowed areas.

Na s a ’ s Stratospheric Observatory for Infrared Astronomy ( Sofia) has detected water molecules in a crater on the Moon’s southern hemisphere. The crater is visible from Earth.

Previous observations of the Moon’s surface detected some form of hydrogen, but were unable to distinguish whether it was water or its close chemical relative, hydroxyl (OH).

The researchers found water in concentrations of 100 to 412 parts per million. The Sahara desert has 100 times the amount of water that Sofia detected.

Paul Hertz, director of the astrophysics division in the science mission directorate at Nasa HQ in Washington, said: “This discovery challenges our understanding of the lunar surface and raises intriguing questions about resources relevant for deep space exploration.”

It is still unclear how easy to access the water will be.

Nasa says the discovery raises new questions about how water is created and how it persists on the harsh, airless lunar surface.

Under Nasa’s Artemis programme, the agency is eager to learn all it can about the presence of water on the Moon in advance of sending the first woman and next man to the lunar surface by 2024 and establishing a sustainable human presence there by the end of the decade.

S o fi a o ff e r e d a new means of looking at the Moon. Flying at up to 45,000 ft, the modified Boeing 747 S P jetliner trained a 106in diameter telescope on the Moon.

The experts say several forces could be at play.

Micrometeorites raining down on the lunar surface, carrying small amounts of water, could deposit the water on the lunar surface.

Another possibility is there could be a two-step process whereby the Sun’s solar wind delivers hydrogen to the lunar surface and causes a chemical reaction with oxygen-bearing minerals in the soil to create hydroxyl.

Meanwhile, radiation from the bombardment of micrometeorites could be transforming that hydroxyl into water, Nasa said.

It added that the water could be trapped into tiny bead-like structures in the soil that forms out of the high heat created by micrometeorite impacts.

Another possibility is that it could be hidden between grains of lunar soil and sheltered from the sunlight, potentially making it more accessible than water trapped in bead-like structures.

Libby Jackson, UK Space Agency human exploration programme manager, said: “Using a small amount of the Mo o n’s natural resources could make it easier for astronauts to explore the Moon and the hope is that these pockets could be used to create drinking water and rocket fuel on the lunar surface.”

In a separate study published in Nature Astronomy, researchers say hidden pockets of water on the moon could be much more common than previously thought.

RETHINK: Water may not be limited to shadowed areas.