For all you Northerners, NASA has good viewing news for you.
What are the signs of spring? They are as familiar as a blooming Daffodil, a songbird at dawn [SkyePuppy: Are they crazy? The mockingbird started singing at 2:09am last night and at 1:22am the night before.], a surprising shaft of warmth from the afternoon sun.
And, oh yes, don't forget the aurora borealis.
Spring is aurora season. For reasons not fully understood by scientists, the weeks around the vernal equinox are prone to Northern Lights. Canadians walking their dogs after dinner, Scandinavians popping out to the sauna, Alaskan Huskies on the Iditarod trail—all they have to do is look up and behold, green curtains of light dancing across the night sky. Spring has arrived!
This is a bit of a puzzle. Auroras are caused by solar activity, but the Sun doesn't know what season it is on Earth. Yet it seemed to know on March 1st when these lights erupted over Tromso, Norway:
"It was a very powerful outburst of Northern Lights," says photographer Bjorn Jorgensen. "The ground actually turned green!"
The NASA article goes into more detail on why we get the Northern Lights, including explaining that the magnetic ropes connecting the earth to the sun are favored in the spring.
So brave the cold at night for the next few weeks, and keep looking up.