Whether or not you’ve seen them in Alaska or Greenland, the spectacular aurora borealis — or, the northern lights — are a mystical, fascinating sight.
The natural phenomenon can be seen in both the northern and southern hemispheres and originate at the sun’s core. When hydrogen and helium atoms are squeezed together, they create a nuclear reaction that releases energy and produces magnetic fields inside the sun, according to the In The Know video above.
Some of those magnetic fields then break off into space, which creates a solar storm. The storm, which looks like a light flare in space, travels past Mercury and Venus until it reaches Earth within two or three days, where our planet’s magnetic field breaks up the storm.
This process releases gases that get funneled to the north and south poles, which creates the stunning colors you see in the sky.
The northern lights can be seen most nights in certain areas in the world and can occur at any time of the day, but are only visible to the naked eye at night.
The colors depend on how far away the Earth’s magnetic field is breaking up a solar storm. Blue and purple mean it’s occurring less than 60 miles away, bright green means it’s between 60 to 150 miles away and red means it’s over 150 miles away.
Researchers have discovered that auroral activity is cyclic, and peaks roughly every 11 years. The next peak period is 2025.
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