Astronomy/Aurora Borealis

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Expert: - 11/8/2005


Question
I realize that the cause of the Aurora Borealis is from the particles from the sun hitting our atmosphere, but what causes those particles to shoot out?  

Answer
The intense energy needed to drive particles that generate a brilliant aurora comes from violent explosions on the Sun known as solar flares. Within three days of such a solar flare (a large one can have the energy equivalent of ten million one-megaton nuclear bombs detonated at once) the particles (electrically charged) reach the Earth's polar region and spiral down its magnetic fields.

The process then triggers large currents in the atmosphere, and what we call the aurora. Which is really the atoms of the upper atmosphere - normally UNCHARGED or
neutral-  suddenly acquiring extra charge then discharging when exposed to the incoming currents from the particles.

These electronic transitions in the atoms of the upper atmosphere thus "light up" the atoms similarly to what we see with atoms in a fluourescent tube.

This is what we call the aurora.

Astronomy

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Philip Stahl

Expertise

I have forty years of experience in Astronomy, specifically solar and space physics. My specialties include the physics of solar flares, sunspots, including their effects on Earth and statistics as applied to astronomical investigations.

Experience

Astronomy: more than forty years experience starting with construction of my own simple telescopes. Worked at university observatory in college, doing astrographic measurements. M.Phil. degree in Physics/Solar Physics and more than ten years as researcher.

Organizations
American Astronomical Society (Solar Physics and Dynamical Astronomy divisions), American Mathematical Society, American Geophysical Union

Publications
Solar Physics (journal), The Journal of the Royal Astronomical Society of Canada, The Proceedings of the Meudon Solar Flare Workshop (1986), The Proceedings of the Caribbean Physics Conference (1985). Books: 'Selected Analyses in Solar Flare Plasma Dynamics', 'Physics Notes for Advanced Level'.

Education/Credentials
B.A. Astronomy, M. Phil. Physics

Awards and Honors
American Astronomical Society Studentship Award (1984), Barbados Government Award for Solar Research

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