What is responsible for water on the Moon? A new study reveals

Water on the Moon has captured human curiosity for decades. Scientists have long been puzzled by the presence of water on the Moon, a seemingly dry and inhospitable place. Now, a new study led by NASA’s Goddard Space Flight Centre offers strong evidence that the Sun itself might be helping create it. The idea sounds surprising, but it makes sense when you consider the constant stream of charged particles that the Sun sends into space. These particles interact with the Moon’s surface in ways that may actually produce water. This discovery could change the future of lunar exploration by making the Moon’s soil a valuable resource.

The idea sounds strange, but it’s surprisingly simple. The Sun constantly blasts the solar system with a stream of charged particles called the solar wind. These particles, mainly made of hydrogen protons, strike the Moon’s dusty surface, known as regolith, which is completely unprotected by a magnetic field or atmosphere.
When the solar wind hits, the protons can grab electrons from the lunar soil, becoming hydrogen atoms. These hydrogen atoms then react with oxygen trapped in Moon minerals like silica, forming hydroxyl (OH) or even full water molecules (H₂O).

Researchers recreated this process on Earth by simulating the solar wind in a specially designed, contamination-free lab setup. Using real lunar dust collected during NASA’s Apollo 17 mission, they bombarded the samples with mock solar wind over a period equivalent to 80,000 years of lunar exposure.
The result? Using light analysis tools, they detected a clear signal that molecules resembling water had formed on the Moon dust. Though scientists can't yet fully distinguish between hydroxyl and pure water, the evidence shows that solar wind plays a big role in creating both.

Finding out that water can be created naturally by solar wind changes how we think about resources on the Moon. If even small amounts of water can form this way, astronauts on future missions might be able to harvest it directly from the lunar soil, providing drinking water, breathable oxygen, or even fuel for rockets.
This could make long-term human presence on the Moon much more sustainable and less dependent on costly Earth-based supply missions.

NASA's focus on the Moon's South Pole, an area where permanently shadowed craters might trap frozen water, now seems even more important. Future missions might combine mining frozen water deposits with harnessing the ongoing water-creation process sparked by the Sun.
Thanks to groundbreaking lab work and a bit of lunar dust from decades ago, scientists are closer than ever to unlocking the Moon’s hidden resources.
And who knows? One day, the Sun might not just light up our sky — it could help fuel humanity’s next giant leap.