What Are the Northern Lights (Aurora Borealis)? And Where Can You See Them?

Primary Image

Where the Northern Lights Are Visible, and What Causes the Auroras

Print Friendly and PDF
No content available.
Body

Aurora alert! In early June 2024, we expect to see colorful, shimmering lights in the night sky. What are the aurora borealis, also called the Northern Lights? What causes them? Almanac astronomer Bob Berman explains.

What Are the Northern Lights?

The aurora borealis, which often appears like dancing ribbons of green and purple in the night sky, originate from the Sun itself!

The stormy, active Sun constantly throws off energized particles from its upper atmosphere. When these particles travel at high speeds toward Earth, our planet’s upper atmosphere protects us. The particles collide with gases in Earth’s atmosphere, creating colorful lights in the sky.

  • In the Northern Hemisphere, the event is called the aurora borealis, which means “dawn of the North,” or the northern lights.
  • In the Southern Hemisphere, it is called the aurora australis, which means “dawn of the South,” or the southern lights.

aurora-borealis-69221_1920_full_width.jpg

2024 Brings the Best Northern Lights in 20 Years

The Sun has weather just like Earth! At times, it is very stormy and ejects more charged particles and solar flares, which are large eruptions of electromagnetic radiation. These create the auroras.

This storminess is especially severe when the Sun is nearing the peak of its 11-year solar cycle and its “solar maximum.” Current Solar Cycle 25 began in December 2019. Experts believe that the Sun may peak in mid- to late 2024. Read more about Solar Cycle 25.

Thanks to the especially stormy Sun, we see auroras more frequently and often more extreme than we have in many years.

See my article about aurora displays forecasted for June 6. 2024!

Solar flares. Credit: NASA

What Causes the Auroras?

The streams of charged particles that erupt from the Sun’s surface can travel at speeds of up to a million miles per hour. As strong solar activity enters the Earth’s magnetic field, the particles (electrons and protons) collide with gases in the upper atmosphere, which causes the gases to glow. As billions of collisions occur in sequence, auroras appear to move or “dance” in the sky.

Because of the shape of Earth’s magnetic field, the charged particles stream towards the poles. This is why auroras are most often seen in the high latitudes near the North and South Poles. They can appear as curtains of light moving across the entire sky and sometimes appear as huge arcs and pillars of color that dance and float through the dark.

Auroras often start with a green glow. You could see shades of green, red, yellow, purple, and blue. The colors depend on the energy level of each gas particle and which gas particles are present. The movement is also beautiful. When the solar winds ripple through the magnetic field, the curtains of light appear to dance, brighten, or fade.

One of the most colorful auroras occurred in March 1989. It was visible in Canada and the United States and as far south as Mexico. The electrical surge that accompanied it was so strong that parts of Canada were blacked out all night!

Aurora borealis as seen from the International Space Station (ISS)
The aurora borealis as seen from the International Space Station (ISS).

When Can You See Auroras? When Are the Northern Lights?

While auroras are triggered at any time by strong solar activity, the traditional aurora-watching season is during the weeks before and after the vernal equinox and autumnal equinoxes, when we transition between seasons.

Why? According to NOAA, the times around the equinoxes are when the Earth is affected more directly by the Sun’s geomagnetic storms, which cause disturbances in Earth’s magnetic field. This seems to be related to the Earth’s orbit around the Sun and the position of our planet’s magnetic poles at any given time of year.

The best time of the day to spot auroras is late at night and in the early morning (from 10:00 P.M. to about 3:00 A.M.). Look north on a clear, moonless night from a dark place away from city lights.

northern-lights-225514_1920_full_width.jpg

Where Can You See the Northern Lights?

Traditionally, the northern lights are most commonly seen at high latitudes. Aurora fans will often travel to Alaska on a tour to see the sights. 

However, if you live in Canada or the northern-tier states (Maine, Michigan, etc.), you are likely to see the northern lights from right where you are if you make an effort. 

However, in 2024, what’s exciting is that people are reporting viewings not only in the usual places, such as the northern-tier states and Canada, but also in the Midwest and even lower Midwest. There have even been sightings in southern states down to North Carolina, central California, and even Arizona!

Why is this happening? Again, it’s all related to the Sun and the solar cycle. The current Solar Cycle 25 is “heating up,” which means that the Sun is especially active; this increased activity in the Sun’s magnetic field will also expand the visibility of the northern lights. When there are massive solar storms (as is more likely near the solar maximum), the lights will appear farther south. Learn more about Solar Cycle 25.

Just get out away from city lights and look up toward the north.

Aurora Borealis

Fun Facts About the Northern Lights

  • No two light shows are ever the same.
  • The most common colors are green and pink, but the aurora may also appear to be purple, red, blue, or yellow.
  • It’s oxygen in the atmosphere that creates the green light, while nitrogen causes the blue light.
  • A single active display can produce one trillion watts of electricity.
  • Some people claim that they have heard the northern lights hiss and crackle.

Web sites such as Spaceweather.com will report on solar explosions and forecast upcoming auroras. NOAA Space Weather Prediction Center also reports solar flare activity.  If you have a shortwave or CB radio, hearing disturbances or skips can also a be a telltale sign.

Have you ever seen the northern lights in person? Tell us about your experience in the comments below!

About The Author

Bob Berman

Bob Berman, astronomer editor for The Old Farmer’s Almanac, covers everything under the Sun (and Moon)! Bob is the world’s most widely read astronomer and has written ten popular books. Read More from Bob Berman