Explosions in the sky / by Mark Roberts

My Northern Lights Photography Tours have proven very popular, but as I made an ethical decision to only take people out on nights when the aurora borealis are likely to be visible, trips this year have been few and far between. Not because there hasn't been any aurora, but because it's mostly been cloudy.

When I got advance bookings for four people last year for a trip in March, I wasn't very hopeful, but one of the participants said he always has good luck on his trips. He wasn't wrong.

We started off at Raanujärvi, and straight away there was an arc of aurora across the sky. Even at this point I think the group would have been happy. We moved around on the frozen lake, and I took the chance to shoot the lights against the Milky Way.

After a while they seemed to be quieting down. The arc faded, but I was surprised how long it had stayed – almost two hours.

I thought we could move to a different location nearby, to shoot from a new angle. Sometimes it's good to vary your perspective and get some different foreground details.

I honestly didn't think it would get much better. The arc was breaking up a little, but I also saw it was moving a little faster. It still looked good, so we hung around a little longer. I'm glad we did, because soon after it all started to kick off in full force.

I read afterwards that this wasn't the arrival of the expected coronal mass ejection, but a polarity reversal on the Earth's magnetic field, which tipped southwards, letting a stream of solar wind in.

It was very impressive. But then it got even better. Suddenly the whole sky exploded above us! Streams of aurora flickered and blasted down from the horizon to the sky directly above us. I quickly switched to my Rokinon 14mm to capture a wider net of the night sky.

It was just incredible! The whole sky above us was filled with fast moving streams of light, yellow, red, purple. I snapped away, but the one above is my favourite: it looks like Skeletor is looking down upon us about to unleash vengeance!

Even after the main event was over, the sky still shimmered with light; aftershocks from the heavens.

It was one of the best displays I've ever seen. As I write this, a CME is hammering the atmosphere above North America... I can only hope it will continue until tonight. If it does, it could be even more spectacular.