It’s hard to imagine anyone being indifferent to the gloriousness of the northern lights. This incredible atmospheric phenomenon has prompted an entire branch of the tourism industry.
Many people rush to Alaska, Norway, or Greenland every year, hoping to catch glimpses of the beautiful dancing lights in the sky. But that’s unsurprising given that human fascination with these cosmic waves has existed for millennia.
While scientists have discovered what causes the northern lights, some unknowns are waiting to be answered. Still, we know a lot about these twirling colored lights, and you’ll find some interesting facts below.
- The Earliest History of the Northern Lights
- The Name Aurora Borealis
- The Northern Lights Explained
- Understanding the Solar Wind
- Shapes and Colors of Aurora Borealis
- Aurora Borealis vs. Aurora Australis
- Best Time to Observe the Auroras
- Where to See the Auroras
- STEVE, or the Aurora Hybrid
- Can You Hear the Northern Lights?
- Are Auroras Visible From Space?
- Are the Northern Lights Harmful in Any Way?
- Appreciating the Northern and Southern Lights
The Earliest History of the Northern Lights
It’s incredible to think of our ancestors gazing up at the sky and wondering about the northern lights and their meaning. The proof that people have always been mesmerized and curious about this event is found in various historical records.
The earliest suspected evidence of the northern lights is hidden in a cave painting in France and is 30,000 years old. However, more concrete records date back to 568 B.C. during the reign of Nebuchadnezzar II, a king of Babylon. Royal astronomers of this period noted the occurrence of the northern lights, but they weren’t the only ones.
Official Chinese reports from 193 B.C. write about this phenomenon too. These early mentions are significant as they offer insight into how various cultures interpreted the northern lights.
The Name Aurora Borealis
The northern lights are also known as aurora borealis, a name coined by renowned Italian astronomer and engineer Galileo Galilei. Aurora is a Roman goddess of morning, and Boreas, the Greek god of the north wind.
He believed that the auroras occurred due to the sunlight reflecting Earth’s atmosphere, but that’s incorrect. The first use of aurora borealis to depict the northern lights was used in 1619 by Galileo, and it has been the official name of this atmospheric event ever since.
The Northern Lights Explained
More in-depth research into aurora borealis didn’t start until the early 20th century. One of the pioneers in this field was the Norwegian astronomer Kristian Birkeland.
He was the first to introduce the theory that the northern lights are caused by charged electrons coming from the sun’s surface and passing through the Earth’s atmosphere.
His theory was proven correct, and today we know that aurora borealis occurs when the sun’s particles hit against the Earth’s atmosphere at 45 million miles per hour. Still, the planet’s magnetic field protects us from this impact.
Instead of these energized sun particles hitting the Earth’s surface, the magnetic field redirects them toward the poles.
Understanding the Solar Wind
To fully understand how aurora borealis works and what affects it, it’s essential to understand the solar wind. It is a continuous stream of electrons and protons from the sun’s outer atmosphere.
While the solar wind is constant, its speed and density vary and go through different stages during the 11-year cycle of activity. As a result, the radiation levels and the number of ejected particles go from solar maximum to a solar minimum within those 11 years.
These changes during the solar wind cycle affect how the northern lights will appear, how long they will last, and how intense the display will be.
Shapes and Colors of Aurora Borealis
One of the most common misconceptions about the northern lights is that it needs to be cold for them to appear. That’s not accurate, though they can only be observed at nighttime. But you might also wonder what determines the colors and shapes of the northern lights.
The different colors have a straightforward scientific explanation. The lights’ colors depend on which gases the electrons emit and how much energy is exchanged.
For example, oxygen typically shows as green or yellowish, probably the most common color of the auroras. The bright-green color also means that collision occurs between 150 and 50 miles above the Earth.
Nitrogen molecules appear reddish, purple, blue, or even pink and typically occur 150 or more miles above the Earth.
While the changing colors are captivating, the northern lights also appear in different shapes. For now, scientists don’t have a definitive answer as to why the forms occur, but you may be able to see various shapes in a single night.
Auroral shapes are categorized as veils, coronas, patches, rays, curtains, and bands, and some of them appear more static than others.
Aurora Borealis vs. Aurora Australis
We’ve talked about aurora borealis and the northern lights, but this atmospheric phenomenon also occurs in the Southern Hemisphere and is appropriately called the southern lights or aurora australis.
The common name for both is aurora Polaris or the polar lights. While aurora borealis and aurora australis typically occur at the same time during the solar wind, it has been recorded that one lags behind the other occasionally.
Best Time to Observe the Auroras
If you’re planning a trip to see the aurora borealis in person, you should be aware that going after this unique natural phenomenon is risky, meaning there are no guarantees you’ll see it.
Theoretically, you could see aurora borealis any time of the year because it’s a constant occurrence, but clear skies and winter viewing will increase your chances.
Mid-August to late February is the optimal time frame for chasing aurora borealis. On the other hand, catching a glimpse of aurora australis is best attempted between March and September, though clear skies are important too.
Another critical element to consider when choosing the right time to view the auroras is the moon. Most stargazers know that a full moon casts plenty of light into the night sky, which could be a problem when viewing auroras.
For this reason, many travel to the aurora-viewing destination during a new moon. But it’s important to point out that many enjoy seeing the full moon next to the auroras.
Furthermore, the full moon doesn’t necessarily make it harder to see the lights, as it all depends on the strength of the aurora. If the solar wind is particularly strong, the presence of the full moon might not interfere with the experience at all.
Where to See the Auroras
The auroras are most likely to appear within the 1,500-mile radius around the magnetic poles. This area is also known as the auroral oval or auroral zone. While you may see the auroras anywhere in this radius, there are well-known locations to which many go every year.
To observe aurora borealis, it’s probably best to take a trip to Norway, Finland, Greenland, Iceland, Russia, Canada, or Alaska. In addition, you can catch the aurora australis in areas of Australia, New Zealand, Argentina, and South Georgia Island.
Again, going to any of these places does not guarantee seeing the northern or southern lights, but it definitely increases the likelihood of experiencing this fantastic light show.
STEVE, or the Aurora Hybrid
Another relevant atmospheric phenomenon is Strong Thermal Emission Velocity Enhancement, or STEVE, which resembles the auroras but is also different. STEVE can be observed from lower altitudes and is typically closer to the equator than the polar lights.
These narrower lights tend to be more purple and contain distinct green lines. Scientists have discovered that the green lights within the STEVE phenomenon are electrons encountering the Earth’s atmosphere. This discovery classifies STEVE as a form of aurora hybrid.
Can You Hear the Northern Lights?
The tales of the northern lights making sounds come from the Inuit communities, but there hasn’t been any scientific discovery that supports that claim.
The auroras making any sound isn’t feasible, as sound and light travel at different speeds. There are theories that certain solar electrical discharges could make sounds humans can hear, but that’s only a theory.
Are Auroras Visible From Space?
Many astronauts have been lucky to record aurora borealis and aurora australis from space. However, the view of auroras from the International Space Station can sometimes seem more static and less variable than it does from Earth. Still, some recorded occurrences are amazingly beautiful.
Are the Northern Lights Harmful in Any Way?
Sometimes the magnificence of the aurora borealis can be overwhelming and even a little frightening, especially when seeing it for the first time. It might make you wonder if these lights can be damaging to humans in any way.
The good news is that people are perfectly safe to enjoy the northern lights without fear of being harmed. But in some extreme conditions, the electrical particles creating the aurora could damage electric power lines or computer networks.
They could also pose a risk to aircraft flying at extremely high altitudes, although that’s unlikely.
Appreciating the Northern and Southern Lights
Even though aurora borealis and aurora australis represent the same event on two poles of the Earth, there’s no question the northern lights get more publicity.
If you’re planning to experience the northern lights, it’s vital to know that they’re unpredictable, though there are ways to increase your chances of seeing them.
Aurora borealis result from the sun’s gaseous particles colliding with the Earth’s atmosphere and can be viewed from many places worldwide. It appears in many different shapes and colors, all equally fascinating and beautiful. Viewing them in person will surely be a memory that will last a lifetime.