Green moon


We've talked about the green flash of the Sun, a phenomenon where, just for a moment, the light from a setting or rising Sun appears green, rather than the customary red, pink, or gold. It happens when Earth's atmosphere separates the wavelengths of light coming from the Sun in just the right way.

The image above is the one of the best known photographs of the green flash of the Moon. Yes, the Moon can flash green, too. But it's a lot harder to spot. Engineers at the European Southern Observatory in Chile took this series of photos.

New Scientist: A rare green flash from the Moon