These ions are created when charged particles from the Sun pelt the lunar surface, causing particles there to react and become negatively charged. Here on Earth, the planet’s magnetic field stops these particles from ever reaching the surface.
But since the Moon doesn’t have a magnetic field, its surface is extremely vulnerable to these charged particles. Unlike positively charged particles, however, they never make it back into orbit, forcing scientists to study them on the surface instead.
So what is the significance of this?
Here is what the article says: