Aurorae glow when charged atom
particles trapped in Earth's magnetosphere
cascade into the upper atmosphere (ionosphere)
more than 50 miles (80 km) up, producing photons as the particles interact
with atmospheric gases. When coronal mass ejections from the Sun buffet
our magnetosphere in a turbulent
way, a veritable storm of protons
and electrons showers down.
Midnight is the best time to see their spectacular action. The light energy in their displays depends upon the nature of the molecules involved. Nitrogen gases in the atmosphere create blueish hues. Oxygen creates greenish hues. An equal amount of both creates reddish hues. Southern aurora can be seen in the southern hemisphere, New Zealand, etc. Northern aurora can be seen throughout the northern hemisphere. (The Northern Lights)
Forecast of activity -http://www.gi.alaska.edu/cgi-bin/predict.cgi
Select a satellite to view the Earth from.
A view of Earth's lights at night.
A free download for you from John Walker (thanks John), co-author of AutoCAD and, view the Earth from anywhere, the Sun, Moon, etc. A comprehensive astronomy / space / satellite tracking package for Microsoft Windows.
Also from John
-Quantum mechanics teaches us that, at the deepest level, uncertainty rules the universe. There are things we cannot predict, even in principle. HotBits harnesses this fundamental uncertainty of nature to generate truly random bits, unlike the pseudo-random-sequences created by an algorithm on a computer. Along the way, you'll find a discussion of the hardware and software used to generate the random bytes comprehensive enough to build your own, and peek under the hood of quantum mechanics to see why the data are genuinely random, and some of the implications of all this.
-xsunclock: shows you, as an icon or resizeable window, the portion of the Earth currently day and night.
-More from John: Astronomy and space links
-Astronomy link – http://planetary.org
January 2000, pages 28-30, Chandra (NASA's
X-ray Observatory) images reveal a never before seen ring of x-rays around
pulsar at the heart of the Crab
Nebula. "Chandra was able to see the light
year wide ring because the space telescope's angular resolution is
10 times sharper than any other
-Why light is at a constant speed, and what produces it? If the speed of the wave (particles of light) were to fall, charge would be deposited faster than picked up, resulting in a net creation of positive charge. If it weren't constant, then charge conservation (a central tenet of physics) would be breached.
B. Kaler is based at the University of Illinois and studies and reports
on a new star weekly. James wrote
Beyond The Rainbow,
September, 2000. His most recent book is Cosmic Clouds.
next page he talks about light-(from
his latest book).