Aurora Explained: What Causes The Northern And Southern Lights?

~9 min

Don’t let aurora season pass you by! The equinox is approaching, bringing one of the year’s best periods for auroral activity. Whether you hope to see the northern or southern lights, this guide will show you the best times and places to look — and explain what causes this glow in the sky. Use the Sky Tonight app to find the darkest hours in your location, then head outside and look up!

Contents

When is the best time to see auroras?

The best chances to see auroras come when three conditions align: dark skies, clear weather, and high solar activity. This is why winter, the New Moon, and periods of solar maximum are the most favorable times in both hemispheres. Additionally, equinoxes are the times when auroras are especially active.

During winter, nights are longer, especially near the poles, where the Sun doesn't rise at all during the polar night. With the Moon out of sight during its new phase, the sky is even darker, making auroras easier to spot.

However, darkness alone isn’t enough; auroras also depend on the interaction between the solar wind and Earth’s magnetic field. This is where the equinoxes come in. As Earth orbits the Sun, its axial tilt causes the angle between its magnetic field and the solar wind to shift. Around the equinoxes, the alignment is optimal, creating temporary “cracks” in the magnetosphere. These openings allow more solar particles to enter, increasing the likelihood of visible auroras.

When to see the northern lights and southern lights
The graphic shows when you can see the northern and southern lights. The top half is the northern lights’ observation window (September to March), and the bottom half is for the southern lights (March to September). The darkest months — December and January in the north, June and July in the south — are represented with brighter auroras. The strongest aurora activity in March and September is shown as bursts of light.

When is the best time to see the northern lights?

The aurora borealis is most likely to be visible from September to March. It can appear at any time during darkness, but the strongest displays typically occur between 9 p.m. and 2 a.m., with a peak often seen around 11 p.m. to midnight.

The weeks around the March and September equinoxes often bring increased auroral activity. December and January, meanwhile, offer the longest nights at high northern latitudes, giving you more time to catch a display.

Did you know? In high-latitude locations like Svalbard, the Sun remains below the horizon all day from mid-November to late January. That is why you can see the Northern Lights in the middle of the day there.

When is the best time to see the southern lights?

In the Southern Hemisphere, the main aurora-viewing season runs from March to September — the opposite of the northern season. As with the northern lights, your best chances are usually between 9 p.m. and 2 a.m., particularly around 11 p.m. to midnight.

Here, June and July provide the longest, darkest nights, while the periods around the March and September equinoxes tend to bring increased auroral activity.

At the South Pole, the Sun remains below the horizon from March equinox to September equinox. During this months-long polar night, the Southern Lights can appear even in the middle of the day. But, honestly, would you really go to the South Pole just to see the aurora? There are much easier places to see them. Bear with us, and we'll show you where to go.

Polar Lights
Discover how auroras work, what colors they can be, where to see them, and how to photograph them – all in one vivid infographic.
See Infographic

How long do the northern and southern lights last?

Some auroras last only a few minutes, while others can stretch on for hours. There is no fixed average duration, but multiple waves of auroras can appear throughout the night. Especially during periods of heightened geomagnetic activity, which tend to occur more often around equinoxes.

The intensity and duration can vary greatly from one night to the next, making every aurora sighting unique. This unpredictability is part of what makes aurora hunting so exciting — you never know when the sky might suddenly light up.

What is an aurora?

An aurora is a beautiful light display in the sky near Earth's polar regions. An aurora in the Northern Hemisphere is called the aurora borealis or northern lights, and in the Southern Hemisphere, it is known as the aurora australis or southern lights.

Galileo Galilei is generally credited with coining the term “aurora borealis” in 1619. The name combines Aurora, the Roman goddess of dawn, with Boreas, the Greek god of the north wind. “Aurora australis,” the name for the southern lights, comes from the Latin word australis, meaning “southern” and derived from Auster, the Roman god of the south wind.

What causes the northern and southern lights?

The northern and southern lights occur when charged particles from the Sun (the solar wind and bursts from solar storms) collide with gases in Earth's upper atmosphere (mostly oxygen and nitrogen). These particles are directed by Earth’s magnetic field toward the poles.

Auroras appear between 80 and 1,000 kilometers above Earth, forming vibrant curtains, spirals, coronas, rays, and other forms. These shapes follow magnetic field lines. What makes auroras even more mesmerizing is that they seem to “dance,” constantly changing as particle flows and magnetic fields in Earth’s magnetosphere evolve.

Shapes of the northern and southern lights
Just like clouds, the auroras can take many different shapes, from simple arcs of color to intricate, swirling patterns. Here are just a few of the common types.

Why auroras can still be strong in 2026: Solar Cycle 25

Auroras are closely linked to the Sun’s roughly 11-year activity cycle. During its most active phase, known as solar maximum, the Sun produces more sunspots, solar flares, and coronal mass ejections (CMEs) — huge clouds of charged particles that can trigger geomagnetic storms and intensify auroras on Earth.

Solar Cycle 25 reached its maximum in October 2024, with activity far exceeding initial predictions. The cycle is now in its declining phase, but that doesn’t mean the solar activity has suddenly gone quiet. It decreases gradually and unevenly, so powerful flares and CMEs can still occur throughout 2026.

When a strong Earth-directed eruption reaches our planet, it can produce brighter auroras and push them much farther from the poles than usual. So 2026 may still deliver spectacular displays — including in places where auroras are rarely seen.

The Sun lights up your days, but do you really know it? Discover its secrets — from sunspots to the core — in our fun quiz!

Solar Quiz: Discover the Sun's Secrets
How much do you know about our star? Take this quiz to learn fascinating facts about the Sun, its features, and related phenomena.
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Where can you see the aurora borealis and aurora australis?

Auroras are most frequently seen within the auroral zone — a belt about 6° wide, approximately centered around the geomagnetic latitude of 67°. The area where auroras appear at any given moment is called the auroral oval.

During geomagnetic storms, these ovals can expand, allowing auroras to be seen much farther from the poles. The aurora borealis has occasionally reached as far south as the Mediterranean and the southern United States, while the aurora australis has been visible as far north as New Caledonia and Western Australia’s Pilbara region. One of the most extreme cases was the Carrington Event in 1859, when auroras were seen even in the tropics.

Auroral oval
On September 11, 2005, just four days after a record-breaking solar flare, the IMAGE satellite captured this view of the southern lights. The size and shape of the auroral oval change with solar activity. You can check the current auroral ovals on the NOAA Space Weather Prediction Center website.

Best places to see the aurora borealis (northern lights)

Here are some popular and accessible destinations for observing the northern lights:

  • Norway – Tromsø, Alta, and the Lofoten Islands
  • Sweden – Abisko and Kiruna in Swedish Lapland
  • Finland – Rovaniemi and areas north of the Arctic Circle
  • Russia – The Murmansk region, including Teriberka and the Kola Peninsula
  • Iceland – Almost the entire country offers excellent visibility
  • Canada – Yukon, Northwest Territories, Nunavut, and northern Alberta
  • Alaska (USA) – Fairbanks and Denali National Park

During strong geomagnetic storms, the northern lights can occasionally be seen much farther south, reaching parts of Scotland, northern U.S. states (like Minnesota, Michigan, and Maine), and even lower latitudes.

Best places to see the aurora australis (southern lights)

The aurora australis is harder to spot due to the vast oceans surrounding the South Pole and fewer populated areas at high southern latitudes. Still, some places offer great viewing potential:

  • Tasmania (Australia) – Areas south of Hobart and remote beaches like Cockle Creek
  • New Zealand – The South Island, particularly around Dunedin, Invercargill, and Stewart Island
  • Southern Argentina and Chile (Patagonia) – Here, auroras are occasionally visible during strong solar storms
  • Sub-Antarctic islands – Such as South Georgia or the Falklands (for expeditions or researchers)
  • Antarctica – The most active region for the southern lights, but also the least accessible

How to see an aurora?

Here is how to increase your chances of witnessing the northern lights (aurora borealis) or southern lights (aurora australis):

  • Choose the ideal location

Aim for locations within or near the auroral zones, but keep in mind that some areas closer to the poles can have harsh or unpredictable weather. Check the recommended spots listed in the Best places to see auroras section of this article.

  • Time it well

The northern lights are visible from September to March, and the southern lights can be seen from March to September. The optimal viewing hours are from 9 p.m. to 2 a.m., especially from 11 p.m. to midnight.

  • Monitor aurora forecasts

Use websites like Space Weather Prediction Center and SpaceWeatherLive to stay updated on upcoming aurora activity. Watch the Kp index — a value of 5 or higher means there's a good chance of seeing strong auroras.

  • Seek clear dark skies

Avoid city lights to keep the skies as dark as possible. Plan your aurora hunt around the New Moon for minimal natural light, and aim for nights with clear skies and low cloud cover.

To easily find the darkest night for aurora viewing, use the Sky Tonight app. It features a Stargazing Index that combines the Moon phase, weather conditions, and light pollution to show how good the observing conditions are tonight. In the app's Calendar, you can check the Moon phases for each day, and see when total darkness begins and how long it lasts.

Sky Tonight – plan your stargazing night
Use the Visible Tonight and Calendar features in the Sky Tonight app to find the longest and darkest night for aurora viewing.
  • Face the best direction

Once you're at your viewing spot, face north in the Northern Hemisphere and south in the Southern Hemisphere. Make sure you have a wide, clear view of the horizon.

  • Warm up and stay patient

Dress warmly and bring a blanket or chair for comfort. Avoid looking at bright light sources, so your eyes can adjust to the dark. While you wait, use Sky Tonight in night mode to explore stars and planets — it’ll make the time pass more enjoyably.

With the right conditions and a bit of luck, you’ll be rewarded with one of nature’s most awe-inspiring sights!

Aurora myths and legends

Throughout history, people have looked to the glowing skies with awe and curiosity, crafting rich stories to explain the mysterious lights. Here are some of the most fascinating aurora myths from around the world.

  • Scandinavia: The Vikings believed the northern lights were the reflections of the Valkyries’ shining weapons guiding fallen warriors to Valhalla.

  • Finland: The Sámi people thought that auroras were caused by a magical fox sweeping snow into the sky with its tail — that’s why the Finnish word for auroras is translated as “fox fires.”

  • Siberia: The Chuvash believed the aurora borealis was a flying snake and a god of childbearing who distributed the souls of babies.

  • Greenland: The Inuit considered auroras to be the souls of the dead playing football with a walrus skull.

  • North America: The Algonquin people thought auroras were fires lit by their creator, Nanahbozho, to remind them of him and to watch over them.

  • New Zealand: The Māori saw the aurora australis as the reflected glow of torches or campfires lit by their ancestors, who had journeyed south and settled in those distant lands.

  • Australia: The Aboriginal Australians interpreted the aurora australis as fires in the spirit world or omens from ancestral beings.

FAQ

Why do the auroras have different colors?

Aurora colors depend on the type of gas in the atmosphere and the altitude where the charged particles collide with it:

  • Green – Caused by oxygen at altitudes of about 100 to 200 km
  • Red – Also from oxygen, but higher up, above 200 km
  • Blue/Purple – Produced by nitrogen at about 100–200 km
  • Pink/Yellow: Rare blends of red with green or blue, seen during high solar activity

The most common aurora color is green.

Are the northern and southern lights really that colorful?

Yes, the northern and southern lights can be marvelously colorful, but what you see with the naked eye is usually less vivid than in photos. Green is the most common and visible color, while reds, purples, and blues often appear faint or grayish in real time. Light pollution and clouds may also obscure the view. However, under very dark conditions with strong aurora activity, you may naturally see a wide range of colors.

Is there a difference between the northern and southern lights?

The northern and southern lights are essentially the same natural phenomenon. However, they are viewed from opposite poles of Earth, and their visibility seasons are reversed. Auroras in both hemispheres can occur simultaneously and in similar patterns, but there may be slight differences in their shapes and timing due to variations in the Earth's magnetic field and the direction of the solar wind. Also, the aurora borealis is better known and more frequently observed because it’s easier to reach high-latitude locations in the Northern Hemisphere.

Are auroras dangerous?

Auroras occur so high up in the atmosphere that they don’t pose any danger to people watching them on the ground. However, the solar storms that trigger strong auroras can impact technology, potentially disrupting GPS, radio signals, and satellite operations.

Are there auroras on other planets?

Auroras aren’t exclusive to Earth — they have also been detected on other planets and moons. Jupiter’s auroras are particularly spectacular: its enormous magnetic field channels charged particles toward the poles, producing displays that are much larger and more powerful than those on Earth. Unlike Earth’s auroras, they are driven mainly by Jupiter’s rapid rotation rather than by the solar wind.

Auroras can even occur on Mercury, despite its lack of a substantial atmosphere: energetic electrons can strike its surface and produce X-ray fluorescence. These emissions are invisible to the naked eye and can only be detected by specialized telescopes and spacecraft.

Northern lights and southern lights: conclusion

The northern and southern lights (aurora borealis and aurora australis) are among the most mesmerizing natural wonders on Earth — dancing waves of light that can be seen with the naked eye. They’re a result of solar wind interacting with Earth’s magnetic field.

The best chances to see auroras come when solar activity is high, the nights are darkest, and you’re in a low light pollution area close to the poles. Use the Sky Tonight app to find the darkest night and plan ahead for the perfect viewing conditions. Save this article so you can come back to it when your ideal aurora night approaches.

Wishing you clear skies and a stunning display of colorful auroras!

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