Hunting Aurora Borealis : a Cookbook
I wrote this guide after a journey to Tromsø, Norway. My dream was to see Aurora Borealis, or Nothern Lights, but the price of the proposed Nothern Light Chase excursions (where local guides take you by bus to secret spots to see them) was prohibitely high; I was sure you could see them by yourself. Funny thing, at first we didn't find many information on how to bypass those organized tours ;)
You'll find here the techniques and the spots near Tromsø to see some Auroras without the tours.
We booked a car at the airport, and went on the hunt. The first two days were completely unsuccessful : even with a clear sky, we could not catch any glimpse of a green moving light.
A key discovery. After a few days of frustration, we realized that bad luck was not the only factor. While talking with a local waitress, we were told that northern lights are similar to rainbows : under the right meteorological conditions, it is rather common to see them. We also learnt that spotting those lights is best done using a DSLR (a Reflex camera), a totally new information! As surprising as it may seem, we started seeing Auroras right after that :)
If you're on this hunt yourself, good luck !
Structure of this guide. This is a cookbook, a step-by-step guide, rather than an verbose article. Tips on the hunt are organized in chapters and sorted by importance.
Step 1 : The obvious
Plan your trip during the winter, and during well-known peak activity periods (we went during the end of February).
Step 2 : The kinda-obvious
Have a way of moving around; we rented a car at the airport for around 200€ for four days (that’s the price for one person, one night on a Nothern Light Chase excursion).
Check the weather forecast; on one hand, massive clouds (and rain, snow, blizzard) will prevent you from seeing the auroras which materialize high in the atmosphere, above those clouds; on the other hand, small clouds are not a problem.
Use your car to reach a darker spot: partially true, as it is easier to see them in a dark environment; you do not need a pitch-black night (we saw auroras at KP0 with a full moon, and we were not too far from a street light). However, you do want to travel away from cities, which make the whole area brighter.
Check on http://yr.no which provides a real-time cloud map, with 4-hour predictions. Unfortunately the system really displays only rain clouds, so it might indicate a clear sky when there is fog, but at least you should not wait hopelessy below a big rainy cloud, and you can plan ahead.
You also need a DSLR, or Reflex camera, and a tripod in order to sucessfully chase weak auroras.
Step 3 : The non-obvious, black-magic part
Checking the KP-index, or the expected strenght of solar activity (linked to expected strength of auroras), is not really important (we saw weak but beautiful auroras at KP0/KP1). Obviously, a high KP-index means a better chance to see auroras, and a better intensity.
You need to chase auroras with a camera, not with the human eye. Set your camera as explained below. Then, with your eyes, be patient and wait for something that could be an aurora. When in doubt, use your DSLR to take a picture : even the weakest aurora will show as green on your camera. No green -> no aurora; some green -> there is one, and if your lucky, it will grow stronger in the coming seconds / minutes. Success !
It is really a chase : weak auroras are completely gray to the human eye (example here), and look like a cloud; only the shape is a hint (long strips that move much faster than a cloud / in the opposite direction of the wind). In addition, the phenomena is really ephemeral : if you wait in the car, you need to rush out to take a picture, as weak ones stay only for a few seconds.
Auroras are really bursty events : on a several-hour wait in our car, a normal pattern would be :
- the sky is cloudy, we wait (1 hour)
- the sky is clear, no sign of anything, we wait and check actively (30 min)
- weak aurora spotted, confirmed with DSLR : we go out and enjoy / pray.
- multiple auroras follow the first one, with increasing intensity. Incredible time :) (5-15min)
- auroras have disappeared, sky is calm again. Wait for the next one (30min)
Step 5 : ???
Step 6 : Profit
You definitely do not need to use the organized trips, which are expensive and constraining; while we lost two first days not really knowing what to do, and probably missed a few auroras, the two last days were a success. Plus, it seems much more fun to be hunting on your own, rather than following the bus guide surrounded by a crowd of noisy tourists (we actually followed a bus with the car once, that was fun).
Step 7 : Additional information
7.1. Camera tuning
|Focus||Manual (Automatic doesn't work with low contrast scenes anyway)|
|Focus Point||Infinity (remote objects are sharp, close ones are blurry)|
|Vibration Reduction (VR)||Off (not needed on a tripod)|
|Aperture||Biggest aperture (2.8", 3.5")|
|ISO||800 (maybe 1600 but not higher to avoid noise)|
|Exposure time||around 5-10sec, to be tuned on the spot|
7.2. How a weak aurora looks like to the human eye
The left column shows degraded pictures, trying to mimic what I saw.
7.3. Spots were we saw auroras
This is our lucky spot, we saw beautiful ones two days in a row at KP1/KP0.
This is one of the spots were the Nothern Light Chase buses go. The scenery is nice, but expect a few buses of people waiting (also they all say "ahhhh" when one arrive, which might or might not be a good thing)
This is known to be a really nice spot (the Norvegian waitress pointed us there), but we didn't see anything.
Generally speaking, the island of Grøtfjord has really nice spots for aurora photography.