What Causes the Northern Lights?
The appearance of rainbows after a rain shower and the disappearance of the Sun during a total solar eclipse are not the only observable natural phenomenon in the skies above. The Aurora Borealis, also known as the Northern Lights, are incredible displays of light that occur near the magnetic pole of the Earth’s Northern hemisphere.
But what causes this phenomenon, what makes the Northern Lights so colorful, and when can you actually see them? Let’s take a look at what causes the Aurora Borealis, or the Northern Lights, and how you can experience this amazing natural wonder of the world for yourself!
What Do The Northern Lights Look Like?
The Northern Lights are visible at night, and are best observed in parts of the Northern hemisphere that are devoid of light pollution. This includes places such as Northern Alaska, Norway, and Canada, or Southern Iceland or Greenland.
Like a rainbow, every appearance of the Northern Lights is unique. For many observers, the Northern Lights appear as bands of glowing greenish-blue arcs tinged with red that light up the sky, while others see the lights moving, pulsing, rippling, rolling across the sky!
What Causes the Aurora Borealis, Or Northern Lights?
The presence of the Northern Lights is actually connected to the Sun –– specifically, to solar activity. Part of what makes the Northern Lights so fascinating is this direct relationship between the aurora borealis and solar activity. This relationship was first considered back in the 1880s, and was later confirmed by more modern scientific methods in the 1950s. In fact, research is still underway today to study the Northern Lights at the University of Alaska at Fairbanks.
When the Sun’s atmosphere emits solar winds in the direction of the Earth, those winds carry with them charged particles: protons and electrons. Thanks to the solar wind, those particles eventually reach the Earth’s atmosphere.
Usually, the Earth’s magnetic field deflects the majority of these charged particles from the Sun. However, at the Earth’s northern and southern poles, that magnetic field is weaker. This creates an opening for the charged particles carried by the solar winds to penetrate our atmosphere and collide with gaseous particles in the upper atmosphere, typically oxygen and nitrogen. The result of the charged particles from the Sun striking the atoms of the gases floating above the Earth is a release of energy, which manifests in the form of colorful light.
Colors of the Northern Lights
What makes the Northern Lights so colorful are these collisions, but it all depends on the altitude and the type of gas with which the Sun’s particles are colliding. For example, the most common aurora is the often-photographed greenish-yellow band, which is produced by charged solar particles striking oxygen roughly 60 miles above the Earth’s surface.
There are rare instances where observers will see glowing red Northern Lights; this occurs when particles collide with oxygen at about 200 miles or more above the Earth’s surface. When particles strike nitrogen rather than oxygen at lower altitudes, it produces a blueish purple aurora.
In general, the Northern Lights can extend from 50 miles to nearly 400 miles above the surface of the Earth, with colors that cover the full rainbow spectrum –– from indigo and violet through orange and red!
When to See the Northern Lights
The Northern Lights tend to be most visible between the autumn and spring equinoxes, or in the late fall and early spring. They are at their most brilliant during the phase during the peak of the solar cycle when coronal mass ejections (CMEs) spike, or about every 11 years.
Of course, it is critical that you are in a geographic location that enables you to view the phenomenon, such as Northern Alaska or Southern Greenland. These are remote regions to travel to, and you’ll need to bundle up, but the challenge of getting there is part of what makes the Northern Lights such a rare and unforgettable experience in the first place!
Continue Your Study of Light
At Rainbow Symphony, we want to encourage the next generation of celestial explorers by creating educational tools to assist in your study of light and color. We provide a wide variety of eclipse shades for experiencing solar eclipses, diffraction glasses for observing the full spectrum of visible light, and so much more.
Satisfy your curiosity when you browse our entire inventory of products and find more educational resources when you read the rest of our blog. As always, be sure to contact us at by filling out our contact form!
