Why would a lightning-struck tree glow after being hit?
It is not on fire and does not give off heat, but glows.
It was a dark and stormy night. Chris emails he
was walking in the woods "a little after a thunderstorm" when he
noticed the tree. The tree, shattered by an earlier lightning
stroke, stabbed the night like a broken pike. An eerie glow extended ...
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Auroras and sunspots flare together
![[NOAA] Aurora over Antarctica’s South Pole Station, 1979](http://www.wonderquest.com/images/2003-05-23-aurora-antarctica.jpg) Q: When do auroras occur? —"lbla", Sandy, Utah
Aurora over Antarctica’s South Pole Station, 1979. Photo courtesy of NOAA.
A: Auroras usually happen
one to four days after a solar flare. In fact, the University of Alaska makes
routine aurora forecasts, based on such disturbances. Why?
The Sun radiates a wind of electrons and protons into space,
much like a child’s Sun drawing. The particles, interact with Earth’s magnetic
field, and trickle into the atmosphere usually near the poles. As they hit
molecules and atoms of the high, thin air, the particles glow.
When the Sun erupts at spots along its surface, the solar wind
strengthens in gust-like fashion. In a couple of days, the gusty particles rain
into Earth’s atmosphere and glow as they hit the air with enhanced intensity.
The storm forms the shifting patterns of light we call auroras.
Further Surfing:
University of
Alaska: Aurora forecasts
University of Alaska: Aurora prediction map
Franck Pettersen, University of Tromsr:
Auroras cause
The Exploratorium: Auroras
(Answered May 23, 2003; updated Oct. 22, 2007)
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