Light RainPurple and green light seems to rain from the starry sky during an aurora, seen last Thursday from Ramsund, Norway.

Aurorae are created when charged particles from the sun flow along Earth's magnetic field lines. The particles hit Earth's atmosphere at the Poles and excite air molecules, which release the extra energy as light.(See pictures of auroras triggered by a recent solar storm aimed directly at Earth.)
Photograph courtesy Kaspars Kurcens

Space Photos This Week: Aurora "Rain," Moon Pit, More

Northern lights shine, the sun spits fire, the moon gets a color treatment, and more in our picks of the week's best space pictures.

September 16, 2010