Aurora Borealis - Also called the “Northern Lights,” the aurora borealis is a natural display of lights in the sky triggered by collisions of charged particles from the Sun with the upper atmosphere of the Earth.
Electromagnetic Wave - Waves containing electric and magnetic fields that make up light, microwaves, x rays as well as over-the-air TV and radio broadcasts.
Plasma - a collection of electrically charged particles, such as those streaming from the sun; the earth’s upper atmosphere also contains lots of plasma.
Alfvén Wave - A kind of electromagnetic wave that describes the motion of an aurora; it exists in a plasma and in the presence of a magnetic field and travels in the direction of the magnetic field’s force.
Solar Activity - The sun is an active star, and experiences its activity in patterns called solar cycles, where one cycle lasts over approximately 11 years. At its solar maximum, next expected to peak in early 2013, the sun is most active, and can have the greatest effect on electronic devices and the occurrence of auroras on Earth.