Glossary

Alfven Waves: Magnetic waves that travel along a magnetic field, much as waves will travel along a taught string that is plucked, or a garden hose that is whipped up and down
quickly, generating a bump that moves along the hose.

Aurora: The glowing light that is emitted when molecules of air in the upper atmosphere are excited, often by the impact of high-energy particles streaming down from space, and release this excited energy in a glowing display of colorful, dancing lights in the polar skies.  Technical term: Aurora Borealis (northern hemisphere) and Aurora Australis (southern hemisphere)

Ionization Storm: A huge increase in the ionization of the very thin air in the upper atmosphere due to bombardment by the intense x-ray flux of a powerful solar flare. May lead to a significant impact on radio signals to aircraft as well as communication and GPS navigation satellites.

Magnetic Reconnection: When two differently oriented magnetic field lines are forced to collide, the process by which both field lines are broken and reattached to the opposete field line, generally allowing the newly formed magnetic field lines to snap back like a broken rubber band, potentially releasing a large amount of energy.

Magnetic Storm: The resulting sharp changes in the magnetic field at the Earth’s surface when a coronal mass ejection collides with the Earth and compresses the Earth’s magnetic field. Technical term: Geomagnetic Storm

Magnetic Substorm: A cycle occurring when the magnetic field carried by the solar wind turns to a southward direction, enabling magnetic reconnection to merge the Earth’s magnetic field with the interplanetary magnetic field. The resulting changes in the magnetic flux are carried towards to tail of the Earth’s magnetosphere where a subsequent magnetic reconnection event causes a shift in the configuration of the magnetic field.  These changes are carried by Alfven waves down toward the Earth’s poles, accelerating electrons on their way that generating the glowing lights of the aurora.

Magnetic Tsunami: A massive cloud of plasma and its embedded magnetic field that, during a period of violent activity on the surface of the sun, erupts from the sun and barrels through the solar system at several million miles per hour. Technical term: Coronal Mass Ejection (CME)

Proton Hailstorm: A deluge of protons (and often electrons as well) that, during solar flares or at the leading edge of magnetic tsunamis, are accelerated to nearly the speed of light and spread out as they stream through a region of the solar system. Technical term: Solar Energetic Particle (SEP) Event

Solar Corona: The hot, thin atmosphere of the sun, made up of a plasma of about a million degrees Celsius.

Solar Flare: A massive release of energy as x-rays during a violent event on the surface of the sun.

Solar Wind: The very low density plasma that is continually accelerated in the solar corona and then streams through the solar system at about one million miles per hour.