Surely you’ve heard of the aurora borealis, also known as the northern lights. It’s probably one of the most visually stunning scientific phenomenons there is, but do you know why it happens, or what makes it so colorful and spectacular? This list is full of aurora borealis facts that you probably didn’t know. It explains how, where, and when these lights happen, and much more about their properties and their history.
The aurora borealis pictures on this list are also stunning. You’ll be ready to pack your bags and head to the Arctic to see the lights for yourself. But be sure to finish reading the list first for some helpful hints on the best times to catch them.
It’s Caused by Sun Particles Colliding with Gas
The sun releases particles of plasma, known as solar wind, and sends them shooting towards earth. These particles are then drawn to the charged poles of earth’s magnetic field, which is why the aurora borealis is only visible near the north pole. As the particles pass through the magnetic shield, they collide with gases, creating the colored lights.
It Has a Twin at the South Pole
Charged ions from the sun are as drawn to the South Pole as they are to the North Pole. The southern light show, called the aurora australis, is less well-known than the aurora borealis because not many people have seen it. Antarctica is an inhospitable continent, and there aren’t many locations on other continents where the southern lights are visible.
Different Elements Make Different Colors
When the sun particles collide with oxygen gas, they produce green light, or a mixture of red and green. Nitrogen creates either blue or red, and helium creates blue or purple.
Green Is the Most Common Color
If you ever see the aurora borealis, you’re most likely to see a lot of green. The second most common color is pink, followed by a mixture of green and red, then pure red, then yellow. Pure blue is the rarest color.
It’s Named After a Greek God and a Roman Goddess
Aurora is the Roman goddess of the dawn who used her torch to wake the world every morning. The second part of the name, “Borealis,” comes from Boreas, the Greek god of the north wind.
It Was Named by Galileo (Possibly)
It’s Been Studied Since Aristotle’s Time
Whether it was first named by Galileo or Gassendi, the aurora borealis was fascinating intellectuals long before it got its modern name. Aristotle was one of the first thinkers to try to explain the phenomenon. It’s also provoked the curiosity of Descartes, Tycho de Brahe, and Benjamin Franklin.
It Can Cause Radio Interference
The sun particles that cause the aurora borealis can also cause radio interference. During solar storms, people have noticed effects on satellites and other electronic equipment.
It Can Cause Power Blackouts
In addition to radio interference, some major power blackouts have been attributed to intense solar storms. Clearly, the northern lights are more than just a pretty show.
It Can Crackle and Clap
The aurora borealis isn’t just a visual phenomenon; it can also produce crackling and clapping sounds. A 2012 study attributed these claps to geomagnetic disturbances caused by the solar ions, but even that explanation seems murky.
It Used to Be Visible Much Farther South
Archeologists have found cave paintings in southern France which they believe depict the aurora borealis. The paintings are about 30,000 years old. The northern lights may have been visible much farther south back then because there were no artificial light sources, and therefore no light pollution.
It Happens on Other Planets, Too
It Follows a Cycle
Auroras occur more frequently and with greater vibrance when there is high solar sunspot activity. This sunspot activity peaks every 11 years. The last peak was in 2013, so 2024 will be the next year when the northern lights will occur often and will be the most beautiful.
It’s Very Difficult to Predict
Even though the aurora borealis follows a cycle, it is very difficult to predict exactly when the light shows will be visible, so planning a trip to see the aurora borealis involves a lot of luck. Even during years of peak solar activity, scientists cannot tell which direction the solar magnetic fields will point until they are already happening.
It Occurs in the Daytime, Too
The waves of solar ions that produce the northern lights can arrive at any time of the day or night. But you can’t view the aurora borealis unless it’s dark. You also need to be in a place that does not have any light pollution.
Some People Call It “Fox Fires”
There are endless cultural legends about the aurora borealis. In Finland, the phenomenon is calledrevontulet, which translates to ” fox fire.” A Finnish folk story says that lights are caused by a fox running through the snow, sending sparks flying into the sky with its sweeping tail.
The Lights Are Farther Away Than You Think
If you’ve ever seen the northern lights first hand, you probably felt like you could reach out and touch them. This is an optical illusion, though. In fact, the lights are about 60 miles above the earth’s surface, and they can be up to 200 miles away.
It’s Visible from Space
Astronauts on the International Space Station get a side view of the aurora borealis. Sometimes, they find themselves right in the middle of it while they’re passing the North Pole during their orbit.