Cathrine sent me this gorgeous postcard of northern lights in Norway! It is such a nice surprise as I have only one postcard showing northern lights so far!
An aurora is a natural light display in the sky particularly in the high latitude regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere. It's quiet complicated process, but I I think the result is just gorgeous.
Aurora Borealis or the northern lights was named after the Roman goddess of dawn, Aurora, and the Greek name for the north wind, Boreas, by Pierre Gassendi in 1621. The Europeans in the Middle Ages believed that it's a sign from God.
There is also similar light in the south called Aurora Australis or the southern lights.
I'd love to see the northern lights myself some day, but even Cathrine who lives in Norway says that she can rarely see the norther lights in Alesun because of the clouds. Thank you, anyway!