Northern Lights -- Aurora Borealis

Northern Lights over the Headquarters entrance sign in Copper Center, Alaska.

W. Davis BLM

The Northern Lights, also known as Aurora Borealis is a spectacular natural night sky phenomenon in the Northern Hemisphere, especially in Alaska during Fall - Winter and early Spring from late August to April.

Visit the University of Alaska Fairbanks (UAF) Geophysical Institute website for the Aurora Forecast.

What is the Aurora Borealis?

"The aurora is a luminous glow seen around the magnetic poles of the northern and southern hemispheres. The light is caused by collisions between electrically charged particles streaming out from the sun in the solar wind that enter Earth’s atmosphere and collide with molecules and atoms of gas, primarily oxygen and nitrogen.

When the electrons and protons from the sun collide with oxygen and nitrogen in the Earth’s atmosphere, they gain energy. To get back to their normal state, they release that energy in the form of light. The principle is similar to what happens in a neon light. Electricity runs through the light fixture to excite the neon gas inside, and when the neon is excited, it gives off a brilliant light.

The dancing lights of the aurora are seen around the magnetic poles of the northern and southern hemispheres because the electrons from the sun travel along magnetic field lines in the Earth’s magnetosphere. The magnetosphere is a vast, comet-shaped bubble around our planet. As the electrons from the solar wind penetrate into the upper atmosphere, the chance of colliding with an atom or molecule increases the deeper into the atmosphere they go." -- Courtesy of UAF