Guide · ten winters of notes
Most aurora advice is written for people at 55 or 60 degrees, waiting for a storm to push the lights south to them. Here it is the other way round: the auroral oval is usually right above us, and a big storm can actually move the show past us to the south. This page is what we tell friends who visit.
The Kp index is a measure of how disturbed Earth’s magnetic field is, on a scale from 0 (quiet) to 9 (extreme storm). It is calculated every three hours from a network of magnetometers around the world, and it is quasi-logarithmic: Kp 6 is not twice Kp 3, it is a much bigger event.
Two things to keep in mind. First, Kp is a planetary average and is published after the fact; forecasts of it are guesses based on the solar wind. Second, it was designed for mid-latitudes. In Lapland a “low” Kp of 1 or 2 regularly gives a perfectly good aurora, because we are already under the oval.
What matters more on the night is the solar wind arriving at Earth right now — especially the north–south direction of its magnetic field, Bz. When Bz turns southward (negative) and stays there for twenty minutes or more, energy pours into the magnetosphere and a substorm often follows. We keep an eye on the Finnish Meteorological Institute’s auroras and space weather pages, which include magnetometer readings from the Sodankylä Geophysical Observatory itself, a few kilometres from Aino’s yard.
quietG1 storm at Kp 5G5 at Kp 9
| Kp | What we see from 67°N | Share of our aurora nights |
|---|---|---|
| 0 – 1 | Faint, quiet arcs low in the north or overhead. Easy to mistake for cloud until the camera shows green. | 31 % |
| 2 – 3 | Active arcs and moving curtains overhead; short substorms with rays around 22:00–00:00. | 46 % |
| 4 – 5 | Bright curtains across the whole sky, fast movement, coronas possible. Visible with street lights on. | 17 % |
| 6 – 7 | Storm. Red upper edges, pink lower borders, aurora also in the southern sky. Sometimes quieter overhead than expected. | 5 % |
| 8 – 9 | Rare. Deep red sky, the main display mostly to the south of us. Three nights in ten years. | 1 % |
The aurora shines all year round; what changes is whether the sky is dark enough to see it. At Sodankylä darkness returns around 15 August and is gone again by late April.
Season
September–October and March are reliably our best months. Around the equinoxes Earth’s magnetic field is better oriented to couple with the solar wind (the Russell–McPherron effect), and in autumn the lakes are still open for reflections.
Time of night
Magnetic midnight in Finnish Lapland falls at roughly 23:30 local time in winter. Substorms cluster around it. If the sky is quiet at 20:00, go back inside, warm up and look again at 22:30.
Direction
On quiet nights the aurora starts as an arc low in the north. As activity rises it climbs overhead, and in a storm it can fill the southern sky. A wide horizon to the north and a clear view up are worth more than any forecast.
All of these are public places. Drive times are from central Sodankylä in winter conditions. Be kind to the landowners, park off the road and take your rubbish home.
| Spot | Drive | View | Why we go | Watch out for |
|---|---|---|---|---|
| Kitinen river bank, Sodankylä | 5 min | W – N | Five minutes from home; reflections in the river until it freezes in early November. | Town light to the south-east. |
| Orajärvi road clearing | 15 min | N – E | Open bog with a long northern horizon. Our default “is it worth it?” spot. | Reindeer on the road. Park fully off the asphalt. |
| Ukko-Luosto summit | 35 min + 2 km | 360° | Fell top with an all-round horizon and snow-covered spruce in the foreground. | Wind chill and an icy summit path. Spikes on your boots. |
| Lokka reservoir | 1 h 10 | N | A huge flat horizon over the ice. Very dark; perfect for faint, low arcs. | No phone signal along parts of the road. |
| Kaunispää, Saariselkä | 1 h 40 | 360° | You can drive to the top. Coronas overhead with Saariselkä’s lights far below. | Busy with tour groups and head torches on storm nights. |
| Pallastunturi | 2 h 30 | N – E | National park with almost no artificial light. Our darkest sky readings come from here. | The fell road is not ploughed at night. |
| Lake Inari, Inari village | 2 h 40 | N | Joonas’s home shore. Islands on the horizon and a vast frozen lake. | Ice thickness — ask locals before walking out. |
| Kilpisjärvi and Saana | 5 h | N – E | The most reliable sky in Finland, at the tip of the “arm”, with the shapeliest fell we know. | Weather on the fells changes fast. Tell someone your plan. |
Any camera with manual controls will do; a modern phone in night mode gets surprisingly far. Put it on a tripod, switch to RAW, and start here:
Safety, briefly
Dress for standing still, not for walking: wool base layers, a down parka, insulated boots one size up, and mittens over thin gloves. Bring a hot drink and something sweet. Tell someone where you are going, keep the car fuel tank above half, and never stop on the road itself — the trucks on route 4 cannot brake on ice for a photographer.
And look up with your own eyes now and then. The camera sees more colour, but the movement is something you only get live.
Three nights we still talk about.
16 Feb 2016 · Kaunispää
Joonas was guiding a snowmobile group up Kaunispää; Aino and Saara were on a ski holiday and had walked up with a tripod and a thermos. At Kp 6 the sky went mad, the tourists went home at eleven, and the three of us stayed until two sharing the coffee. We swapped numbers in the car park. This site is, in a way, that thermos.
9 Sep 2021 · Lake Inari
We had a perfect reflection on Lake Inari and a red fox that kept walking through the frame, sniffing the tripod legs. Joonas got eleven frames of aurora and fox before it trotted off. None of them were sharp. We still have them on the fridge.
10 Oct 2024 · Ukko-Luosto
The October storm was forecast days in advance, and half of Lapland seemed to come up Ukko-Luosto. Head torches swept across every exposure until a guide from Pyhä asked everyone, politely and loudly, to switch to red light. The cheer when they all went out was louder than the cheer for the corona.