In the past few months the Sun has come roaring back to life, blasting out flares and fierce waves of subatomic particles. These space storms are caused by the magnetic field of the Sun, which stores huge amounts of energy. Near sunspots the magnetic field lines get tangled and can suddenly erupt, hurling that energy into space.
If these tsunamis of particles head our way, they interact with our own planet's magnetic field. Through complicated processes, the particles are focused down into our atmosphere, where they light it up (literally) like a neon sign. The result: aurorae, also called the northern (or southern) lights.
During a recent storm, photographer Dave Brosha was up in Yellowknife, in Canada's Northwest Territories, which is at a latitude of 62° north, not all that far south of the Arctic Circle. The aurora display that night was, well, unearthly. He got some amazing shots, including this one:
[Click to stimulatedemissionate.]
Wow. That's breathtaking. The silhouette belongs to photographer Thomas Koidhis, also a Canadian from the NWT. The stream of green aurora is simple amazing, like a solid path you could walk right into the sky. The Milky Way hangs as a backdrop, the constellations of Cygnus and Lyra punctuating the glowing stream.
He has many more such gorgeous shots in his Flickr set, and I particularly like this one, which shows the ribbons and curved streamers of the lights, caused by the curves in the Earth's magnetic field itself.
I've said it before, and I'll say it many more times in the future: people who say science takes away the magic of reality are wrong. The aurorae are among the most beautiful and amazing sights that nature has to offer, and their beauty is enhanced, magnified, by knowing what it is that causes them.
Knowing is half the fun. The other half? Finding out.
Credit: Dave Brosha, used by permission.