Aurora Glossary

Key Terms and Concepts

A

Aurora Borealis: The Northern Lights, a natural light display in Earth's northern hemisphere.

Aurora Australis: The Southern Lights, a natural light display in Earth's southern hemisphere.

B

Bz Component: The north-south component of the interplanetary magnetic field. Negative Bz values (southward) enhance aurora activity.

C

Coronal Mass Ejection (CME): A large expulsion of plasma and magnetic field from the sun's corona that can trigger geomagnetic storms.

G

Geomagnetic Storm: A disturbance in Earth's magnetosphere caused by solar wind, which can produce intense auroras.

K

Kp Index: A global geomagnetic activity index ranging from 0 to 9, with higher values indicating stronger aurora displays.

M

Magnetosphere: The region around Earth controlled by its magnetic field, which protects us from solar wind.

S

Solar Wind: A stream of charged particles released from the sun's upper atmosphere, which interacts with Earth's magnetic field to create auroras.

Solar Flare: A sudden flash of increased brightness on the sun, often accompanied by a coronal mass ejection.

I

IMF (Interplanetary Magnetic Field): The magnetic field carried by the solar wind through the solar system.