Northern lights: myths and facts

Myth: cold weather causes the aurora

The aurora has nothing to do with the temperature on the ground. It is caused by the solar wind interacting with Earth's magnetic field, and the light is produced 100 km or more above the weather. It is just as active on a mild night as on a freezing one.

The link people notice is real but indirect. In the Arctic, the long dark nights happen in winter, and the clearest nights are often the coldest, because clouds trap heat. So cold, clear nights are good for watching, but the cold is a side effect, not the cause.

Myth: you can only see it in winter

The aurora happens all year round, including during the summer. You just cannot see it when the sky is bright. Above the Arctic Circle, the midnight sun and light summer nights hide it from roughly mid-April to late August.

Further south, for example in Scotland, southern Scandinavia, Canada or the northern United States, the summer nights are dark enough for strong displays to be seen even in June and July. In Tasmania and New Zealand, dark nights happen all year too.

Myth: a full moon means no aurora

Moonlight brightens the sky and hides faint aurora, but it does not affect the aurora itself, and moderate to strong displays are clearly visible under a full moon. Many of the most photographed displays are lit by moonlight on snow.

If you can choose your dates freely, a darker moon helps. But do not cancel a trip because of the moon phase. Cloud cover and geomagnetic activity matter far more.

Myth: the aurora is always bright green and moving

Photos and time-lapse videos have set high expectations. To the eye, a typical display starts as a pale, greyish arc that can look like a thin cloud. Only when it brightens does the green become obvious, and the dramatic dancing curtains appear mainly during substorms, which last 15–60 minutes.

Cameras collect light for several seconds and record colour that your eyes, relying on colour-blind rod cells in the dark, cannot see. That is why photos look more vivid. The aurora colours guide explains this in detail.

Myth: you can hear the aurora

This one is genuinely debated. For centuries people in the Arctic have reported faint crackling, hissing or clapping sounds during strong displays. The aurora itself is far too high, at 100 km or more, for sound to reach the ground in any meaningful way, and it would arrive minutes after the light.

Some researchers have proposed that sounds could be produced much closer to the ground, for example by electrical discharges in a temperature inversion layer during geomagnetic storms. Recordings exist, but the explanation is not settled. If you hear something, it is not coming from the aurora itself.

Myth: you need to go to the North Pole

The aurora is centred on the magnetic poles, but it forms a ring, not a spot. The best place to see it is under the auroral oval at around 65–72° magnetic latitude, which runs through northern Scandinavia, Iceland, northern Canada and Alaska. Very close to the magnetic pole, the aurora is actually seen less often than under the oval.

Myth: aurora forecasts can predict weeks ahead

Reliable aurora forecasts only reach a few days ahead, and precise timing only an hour or less, based on solar wind measured by spacecraft about 1.5 million km away. The 27-day rotation of the Sun gives a rough hint of recurring activity, but nobody can tell you in January that a particular night in March will be good.

Be cautious of any site or tour that promises the aurora on specific dates. The honest approach is to choose a good place and season, stay several nights and watch the short-term forecast.

Myth: the aurora is dangerous

Watching the aurora is completely safe. The particles that cause it stop high in the atmosphere. Strong geomagnetic storms can disturb satellites, GPS, radio communication and power grids, and airlines sometimes reroute polar flights, but there is no effect on people on the ground. The real hazards on an aurora night are cold and icy roads.

Folklore that is worth knowing

• In parts of Sámi tradition, the aurora was treated with respect and caution, and children were told not to wave, whistle or tease it.
• Many cultures in the far north saw the lights as spirits of the dead, often playing or dancing in the sky.
• In medieval Europe, rare red aurora seen far to the south was often taken as an omen of war or disaster.
• These stories are a valuable part of northern culture. They are best enjoyed as heritage, not as advice.

Frequently asked questions

Does it have to be very cold to see the northern lights?

No. Temperature has no effect on the aurora, which happens 100 km or more above the weather. What you need is darkness, clear skies and geomagnetic activity. Clear winter nights in the Arctic are often very cold, which is why people associate the two, but mild clear nights work just as well.

Can you see the northern lights in summer?

Not under the midnight sun or bright summer nights above the Arctic Circle, roughly mid-April to late August. Further south, in places such as Scotland, southern Scandinavia, Canada and the northern United States, strong storms can be seen on dark summer nights. The aurora itself occurs all year.

Is the aurora really as colourful as in photos?

Sometimes, during bright displays, but often it looks paler to the eye than on camera. In low light your eyes rely on rod cells that do not see colour, so faint aurora can look grey. Cameras collect light over several seconds and reveal colour that is really there but too faint for your eyes.

Do the northern lights make a sound?

Reports of crackling or hissing are old and widespread, and some recordings exist. The aurora itself is too high for its sound to reach you, so any noise would have to be produced near the ground. Some scientists link it to electrical discharges during geomagnetic storms, but this is not settled.