on Nov 14, 2019 in
Years of hunting the Northern Lights in Iceland with a strong background in science has given me the skill and understanding to know 100% of the time when it’s worth going out searching for them.
It’s still incredibly difficult to predict, despite my acute knowledge of the forecasts. And just as difficult to understand how it happens at all, despite my extensive research.
My previous article on the Northern Lights focused a lot on ‘how to avoid disappointment when hunting the northern lights’. This article focuses more on teaching you a little and giving you some good hints and tips when you do find yourself out there on the hunt. When I’m running tours that include a night of Northern Lights hunting, usually after a day of adventure or sight seeing, it’s always helpful to teach my guests what we’re looking for. Then I have 12 sets of eyes helping me figure it all out. A team of hunters, armed with our cameras.
What are the Northern Lights? The family friendly version
Every single day, across the entire world, the sun is attacking us. Yes, really! The sun is sending out tiny electrically charged particles (electrons and protons) in every direction known as solar winds. When solar winds are fast enough (over 350km/s), and plentiful enough, they are referred to as ‘solar storms’. These storms are strong enough to affect power grids and satellites. Thankfully they have little effect on the human body, and the atmosphere is so thick that these particles never reach ground level anyway.
When these particles, mainly electrons, hit our magnetosphere (the protective force field around the planet) they usually are rebounded or redirected. At the equator the magnetic field is strongest. Nearer the poles it is weaker. When the magnetic field is temporarily weakened, and when the solar winds are strong enough, some of the electrons can enter the atmosphere high up.
The electrons don’t travel far before they hit off other particles in the atmosphere, mostly oxygen and nitrogen. When they collide with these elements they react (ionise) and cause the oxygen and nitrogen to glow (emit light). This is what creates the Northern Lights in the sky.
When they are green or white it is the electrons colliding with the oxygen and nitrogen at a normal height, around 80km up. If you see other colours like pink and purple it’s because the solar storm is really strong and hits the same elements but much higher in the atmosphere (up to 400km), though the colours can vary at all altitudes. These colour variations are much less likely. I’ve personally only seen the pink colour half a dozen times.
I’m going to stop short of discussing things like coronal holes, sun spots, solar rotation, sun cycle, solar flares and the interplanetary magnetic field. These buzz words are useful for people wanting a more in depth understanding of the Northern Lights but is perhaps unneeded detail for this post, or for your holiday. If you want to know more on this subject auroraforecast.is is a site I visit often for forecasts and explanations.
Let the hunt begin with these 7 tips:
1. Find the right website to show you up to date forecasts
Now that you understand the basic principles of the Northern Lights it’s time to understand the forecast a little better and what to look for in the sky. As above, the best website I’ve found for forecasting the Northern Lights is auroraforecast.is. I’m not affiliated with them in anyway btw. I’m just a big fan of their work. They offer a more in depth scientific forecast which would be hard to elaborate on here without making it an Odyssey sized blog post.
The short version for their website is to click on ‘all cloud cover’ to see where you should drive to. Then check the solar wind speed. If the sky is clear and the speed is above 350km/s then get hunting. Refresh the page every 20 minutes or so as they update it very regularly.
2. Don’t trust the KP Index
I hate the KP index. It is the most misleading gauge I’ve ever seen. It is not a strength predictor. Or how likely you are to see them.
The range goes from 1 to 9 on the KP Index and simply tells you how far from the poles the Northern Lights are likely to appear in the sky. In Iceland we are so close to the North Pole (just outside of the Arctic Circle) that even a 1 on the index can be visible. If it’s a 9 you could see it in northern England on a clear night.
All I use this gauge for is to tell my customers where to look in the night sky. If it’s a 1, 2 or 3 I tell them to look north, and quite low in the sky. On these nights I’ll make a bigger effort to avoid north facing mountains too.
If the KP index is 4, 5 or 6 I will get my guests to look directly up. If it’s a 7, 8 or 9 then the chances are you’ll get dizzy and fall over as you search every inch of the night sky. The KP index only gets up above 7 around 1% of the time so I wouldn’t hold out for that.
Sure, a higher number on the KP index undoubtedly means you are slightly more likely to see the Northern Lights. But a lower number doesn’t mean it’ll necessarily be not worth it, and a higher number doesn’t guarantee a sighting either.
3. Focus on the cloud cover
This is by far the most important factor. If you are in an area with lots of cloud cover then don’t bother even going outside. You won’t even see stars. You can still see the Northern Lights if the cloud cover is high, albeit more of a colourful haze than a dancing ribbon.
Most dedicated Northern Lights companies, especially the ones based in Reykjavik, are mainly looking at cloud cover. They then focus on finding cloudless parts of the sky to set up long exposure cameras regardless of strength.
I refuse to diminish the efforts of some of these companies. Guides can be driving in quite difficult conditions for hours, in the dark, scrunching their eyes up looking for a glimmer of hope. It’s a difficult job and many have quite extensive skills when it comes to getting a great picture on your camera.
I prefer to see companies include the Northern Lights as part of a multi-day tour rather than as stand-alone trips, however, so that if you don’t get the perfect conditions, there are at least other things to see and do along the way and then at least you’ve had a fun day anyway.
4. Don’t be put off by a full moon
You will hear that a full moon has a big negative effect on spotting the Northern Lights. Yes and no really.
Having no moon in the sky is perfect conditions. As is having no street lights. But you’re not exactly going to book your holiday in Iceland based on the phase of the moon are you? Actually, I know a guest who did exactly that, but that’s not the norm.
If the Northern Lights are strong enough it doesn’t matter about the moon (as much). I’ve seen great Northern Lights with moon lighting up the faces of the avid photographers. The position of the moon is often the problem. Not the size. As the moon moves across the sky the areas where the Northern Lights shows up can get better (or worse). Either way, having the moon in the sky is out of your control so you might as well stick to what you can control… the location.
5. Get out of the city and into the darkness
I have said on numerous occasions that you can still see the Northern Lights in Reykjavik. This is absolutely true. My partner has only every spotted them in the city. A fact I like to make fun of her for on a regular basis. But, of course you are going to see a less faded version outside of the city. The pictures on your camera will definitely be easier to take without other lights affecting your long exposure too.
So either join those Northern Lights tour companies that take you out of the city if you’re stuck in Reykjavik. Or walk to more secluded spots of the city, perhaps the lighthouse at the harbour. Or even better, join a multi-day tour where the hotels you sleep in are in the middle of nowhere already. Then you can simply walk in and out of your room with a hot chocolate instead of driving around.
6. Tripods and good cameras are a must
So you’ve probably seen the pictures from friends who managed to get a stunning picture of the Northern Lights on their phones? It is possible. New Samsung and Huawei phones seem to have better settings and apps than what I’ve managed to find on my iPhone.
I’ve actually been quite impressed with what some of my guests have managed with a shaky cold hand. But. And there’s always a but. If the Northern Lights are dancing across the sky in every direction and in multiple colours then anyone can take a good picture.
On the lower activity nights sometimes the camera is your only respite from disappointment. Believe it or not, it’s one of the few things that often look better on your camera than in real life. It goes something like this:
Your guide will triumphantly point to the night sky and say, “Look, there they are!”
Your heart skips a beat as you frantically dart your eyes from star to star looking for the Northern Lights. This is what you came to Iceland to see! After 30 seconds or so you see… nothing. Your frustration is visible, even in the dark. But then your eyes start to adjust to the dark a little (it can take 15 to 20 minutes) and you see this weird skinny cloud. Could that be what the guide is pointing at? It’s grey though???
This is where the skill comes in. It’s a low strength night, but all is not lost.
Set up your stable tripod, attach your camera and set it to manual. Make sure to turn off your flash. Then set the ISO between 1600-3200 with a shutter speed of around 8 seconds. This is a rough guide only so take that first picture and see how it comes out. Then it’s up to you to play around with the settings until you get the perfect picture. I won’t labour this point too much as there’s a 1001 blog posts on exact settings. Trial and error is necessary most of the time.
7. Trust the forecast when it hits the news
I used to tell people you can’t predict the Northern Lights more than 2 days in advance, since that’s how long it takes for the particles to get from the sun to us. Technically that’s true. But as I learned more about how the Northern Lights are formed and how the sun rotates I understood that the sun likes to be repetitive.
If a coronal hole (a place with a high concentration of expelled charged particles) on the surface of the sun sent out a solar storm 27 days ago there’s a good chance once the sun rotates fully back around then that same coronal hole might still be there. It might be smaller, or bigger, but if it was large enough the first time around then put a note in your diary.
Please don’t take this as a definite. Coronal holes open up and close over all the time. Predicting them is impossible. But, if they’re big enough they can last a while before disappearing. Most recently I put my research to the test and predicted them 3 weeks early. I even told the travel agent who was coming during that time about their customers chances of seeing them. Risky, I know. But in this case it was exactly correct. Luckily it wasn’t cloudy when they arrived.
So if you hear about a particularly strong light show before you come on holiday count with all your fingers and toes to see if the sun will be back in the same direction when you arrive (27 days later). Then cross all those fingers and toes until you arrive.
So in essence, as with last months post. Try to find other things to do in Iceland that compliment your Northern Lights pursuits. But if you are out hunting get a good camera, a trusted forecast site and a great guide. Then late nature take its course.
Ryan Connolly is Co-Founder of Hidden Iceland. Hidden Iceland specialises in private trips, taking you to some of the hidden gems of Iceland with a passionate and experienced guide.