Awrabest if you’re looking for aurora
OVER the past few nights, observers across Scotland have been keeping watch for displays of the famous aurora borealis – the Northern Lights – a glowing green phenomenon in the sky.
The Sun, our nearest star, is a very active and dynamic environment. From time to time, its strong magnetic field is disturbed and a powerful solar flare can occur.
Such flares can eject large clouds of charged material from the solar atmosphere (the corona) out into space.
If that solar flare is pointed toward the Earth, that “coronal mass ejection” travels across space to our planet. There it interacts with the Earth’s magnetic field and those charged particles get funnelled down into our atmosphere near the poles. As those particles collide with molecules of gas in the Earth’s atmosphere, they begin to glow – mainly green but also red and blue.
The green colour is due to the glow from oxygen atoms. But there are also reports of red and blue columns of light during aurora, due to the glow from nitrogen atoms.
Earlier this week, intense bands of luminous green were seen swirling in Scandinavian skies as solar wind buffeted the Earth’s magnetic field.
But remember – space weather is as hard to predict as Earth’s weather. The aurora forms as a massive oval around the Earth’s poles. For the most part, you can only see the Northern Lights from high latitudes. This means you usually have to travel to northern locations such as Finland, Norway, Iceland and Canada to see this awe-inspiring phenomena.
From time to time, we see huge spikes of solar and auroral activity. Sometimes we get an extra-large flare from the Sun which causes the auroral oval to expand out and reach much lower latitudes. This we can sometimes see it from Scotland.
However, it’s not always the easiest thing to catch. The Sun is somewhat unpredictable and can produce flares unexpectedly.
Secondly, the Earth isn’t always aligned in such a way as to produce a spectacular aurora – so even a large solar flare doesn’t always mean large aurorae. Lastly, your view of the Northern Lights depends on how dark your location is. The unwanted glow of light pollution will easily block out the glow of the aurora.
If you have access to the internet, there are a number of ways you can increase your chances of observing.
Spaceweather.com has lots of information about the current state of the Sun.
Twitter feeds such as @aurorawatchuk and @Aurora_Alerts can provide up-to-the-minute alerts of aurora, and phone apps like AuroraNotifier will send alerts direct to you. So on a clear night, find somewhere dark, and you might see the Northern Lights.