The Northern Lights

The Northern Lights: Where, Why and How

Almost everyone who travels to Finnmark or the North of Troms in Norway, is chasing the same thing, whether they say it out loud or not. A night when the sky stops being a sky and starts moving. The aurora borealis is the reason a lot of visitors (and even some locals) put up with sub-zero temperatures and long, dark drives in the first place, and it deserves a proper explanation rather than just a photo gallery — what it actually is, why it happens here specifically, and how to give yourself the best realistic shot at seeing it.

What's actually happening up there 🌠

The sun isn't just a ball of light — it constantly throws off a stream of charged particles called the solar wind, and every so often, a solar flare or coronal mass ejection sends a much larger, faster burst of that material toward Earth. Most of it gets deflected by Earth's magnetic field, but the field itself funnels a portion of those particles down toward the two magnetic poles, where they collide with oxygen and nitrogen atoms high in the atmosphere.

Those collisions excite the gas atoms — bump them into a higher energy state — and as the atoms settle back down, they release that extra energy as light. It's the same basic principle as a neon sign: electricity excites gas inside a glass tube, and the gas glows. The aurora is that process happening across hundreds of kilometres of open sky instead of a few centimetres of glass tubing, which is a large part of why it looks the way it does.

This is also why the aurora only ever appears in rings around the two poles — the "auroral oval" — rather than anywhere on the planet at random. Norway's Arctic north, sitting directly under that oval for much of the year, is one of the most reliable places on Earth to be standing in the right spot when it lights up.

Why the colours change 🌌

The colour you see depends on which gas gets struck, and at what altitude:

• Green, the colour most people picture, comes from oxygen at roughly 100–150 km altitude — the most common and easiest colour for both the human eye and ordinary cameras to pick up.

• Red comes from oxygen much higher up, generally above 200–300 km, and needs considerably more energetic particles to appear — which is why a pure red aurora, or a red fringe along the top of a green display, usually signals a stronger geomagnetic storm.

• Blue and purple come from nitrogen, typically lower in the atmosphere (below around 100 km), and tend to show up along the base of a bright, active display.

• Pink, a rarer sight, results from nitrogen at very low altitude during genuinely extreme storms — if you see it, you're watching a significant space weather event, not an average night.

Cameras are also considerably more sensitive to these colours than the naked eye, particularly red — which is why photos from a night out often look far more vivid than what you remember standing there watching. That's not a trick or an editing exaggeration; it's a real difference in how eyes and camera sensors register faint light.

The Kp index, and why it matters more than the calendar

Aurora forecasts are built around the Kp index, a scale from 0 to 9 measuring how disturbed Earth's magnetic field currently is. The higher the number, the further the auroral oval expands away from the poles, and the more intense and lower-latitude the display becomes:

• Kp 0–3: quiet to unsettled conditions — aurora, if visible, tends to sit low on the northern horizon and stay green.

• Kp 4–5: active conditions — the display strengthens and reds can start appearing at the top of taller curtains.

• Kp 6–7: a moderate to strong storm — green, red and purple can all appear together, and the oval expands far enough south to bring aurora to places that rarely see it, like southern Scandinavia or Scotland.

• Kp 8–9: severe storm conditions — rare, and capable of producing aurora visible from much of Europe and the northern United States.

Finnmark and North Troms sit far enough north that even a fairly modest Kp value is often enough for a good show — one real advantage of travelling this far north rather than chasing the lights from somewhere further south, where you'd need a genuinely major storm just to see anything at all.

Why 2026 is an unusually good year to be trying

The sun runs on an roughly 11-year cycle of rising and falling activity, and we are currently deep into Solar Cycle 25, which multiple space-weather forecasters — including NASA and NOAA — place at or near its peak through 2024–2026. Some researchers now expect this cycle to have a "double peak," meaning the elevated activity window extends further into 2026 than a single, simple peak would. Practically, that means more frequent solar storms, a wider and more active auroral oval, and displays that are, on average, brighter and more colourful than they'll be once the cycle starts declining toward its next minimum in the early 2030s. None of this guarantees a display on any specific night — local weather and short-term space weather still decide that — but the underlying conditions this year are genuinely more favourable than they'll be for a while.

When to go 🌃

The aurora is happening above the clouds year-round — the sun doesn't stop emitting solar wind in summer. What changes is whether the sky is dark enough to see it. Above the Arctic Circle, that rules out the midnight sun months almost entirely: from roughly late May to late July, it simply never gets dark enough. The realistic viewing season runs from early September to early April, with the darkest, longest nights — and generally the best odds — falling between November and February, when Finnmark and Troms see close to 24 hours of darkness or near-darkness a day.

Within that season, no single month is definitively "best" — clear skies matter as much as darkness, and this region's weather can vary sharply from one valley or coastline to the next on the same night.

Where to actually stand

Get away from town lights. Even a small town's streetlights wash out all but the brightest displays, and light pollution is the single most avoidable reason people miss a show that was genuinely happening right above them. A short drive out of Alta, Kirkenes, Hammerfest or wherever you're based, to open ground away from direct light sources, makes an enormous difference.

Elevation and open sky help, but aren't essential. A clear, unobstructed view to the north — away from hills, forest or buildings blocking the horizon — matters more than height above sea level. Coastal viewpoints, frozen lakes and open tundra all work well precisely because there's nothing in the way.
Check the weather, not just the aurora forecast. A high Kp forecast is worthless under total cloud cover. This region's microclimates genuinely differ — a cloudy coastal fjord can sit an hour's drive from a completely clear inland valley — so a flexible plan that lets you drive toward clearer skies on the night beats committing to one fixed viewing spot in advance.

Give it time. The aurora rarely performs on command. A quiet-looking sky can burst into activity an hour later, and a lot of "we didn't see anything" reports come from people who gave up after twenty minutes. Dress warmly enough to comfortably wait outside for two or three hours, because that patience is often what separates a good night from a missed one.

Consider a guided tour for your best single shot. Local guides track real-time cloud cover and aurora activity across a much wider area than a visitor checking one app, and can drive to wherever the sky is actually clear that night — a genuine advantage over choosing a fixed spot yourself, especially on a short trip where you can't afford a wasted evening.

Photographing it 💫

A phone camera in a recent "night mode" can pick up a surprisingly good aurora photo these days, but a dedicated camera on a tripod still gives far more control. As a starting point: a wide-angle lens, manual focus set to infinity, an aperture as wide as your lens allows, ISO somewhere around 800–3200 depending on brightness, and an exposure of roughly 2–10 seconds — adjust from there based on how fast the display is moving. A tripod is non-negotiable; even the best settings won't save a handheld shot in near-total darkness. Bring spare, warm batteries — cold drains them fast, and there's nothing worse than a camera dying on the one night everything else lines up.

Setting realistic expectations

The aurora is a natural phenomenon, not a scheduled show, and no operator, app or forecast can promise you'll see it on a given night. What you can do is stack the odds in your favour: travel in the right season, get away from light pollution, stay out long enough to give a quiet sky a chance to change, and keep an eye on both the Kp forecast and the actual weather rather than either alone. Do that consistently over several nights in Arctic Norway during a strong solar year like this one, and the odds are about as good as they get anywhere on Earth.

Solar activity and aurora forecasts shift night to night — check a live Kp forecast and local cloud cover before heading out, rather than relying on general seasonal averages alone. See some of my pictures, taken with just a normal iPhone: