www.flickr.com
Showing posts with label aurora borealis. Show all posts
Showing posts with label aurora borealis. Show all posts

Monday, December 22, 2008

Aurora Anyone?


Stunning photographs from The Telegraph of the Aurora Borealis.

From Wikipedia.

Aurorae are produced by the collision of charged particles from Earth's magnetosphere, mostly electrons but also protons and heavier particles, with atoms and molecules of Earth's upper atmosphere (at altitudes above 80 km (50 miles)). The particles have energies of 1 to 100 keV. They originate from the Sun and arrive at the vicinity of Earth in the relatively low-energy solar wind. When the trapped magnetic field of the solar wind is favourably oriented (principally southwards) it connects with Earth's magnetic field, and solar particles enter the magnetosphere and are swept to the magnetotail. Further magnetic reconnection accelerates the particles towards Earth.
So now you know. Apparently the Southern Hemisphere version is the Aurora Australis. Only visible from really cold parts of this part of the world. Too bad we can't just sit back and watch from our back garden. What we do have living in the suburbs is very clear sky unpolluted by urban light and one in which you can see most of the stars. I find the look of the whole sky more interesting than individual stars.
Reblog this post [with Zemanta]