There's some fascinating science behind the spectrum of colours visible in the aurora.
When you think of the northern lights, if green comes to mind, it's because it's most commonly observed and the human eye can detect green more easily versus other colours.
It's also due to a combination of different gases at different altitudes and the way they are excited and collide.
Here are the colours you'll be most likely to see:
(For useful context, aeroplanes fly at around 10km)
Pink/red - nitrogen at up to 100km
On occasions where solar activity is high, it's possible for the lower fringe of the aurora to show pink or red, caused by nitrogen molecules at around 100km.
Green - oxygen at between 100-300km
The most common colour, which can be seen from Earth and in space. This is a result of oxygen molecules colliding with charged particles at between 100km - 300km.
Red - oxygen at between 300-400km
Higher in the atmosphere at around 300-400k, it's possible for oxygen atoms to cause red aurorae.
A quick search online will show you many more spectacular photos than the ones we've captured on our adventures so far.
There are additional colours visible on occasions:
Purple and blue - caused by helium and hydrogen atoms, these colours are not always easy to see with the naked eye and may be more apparent in photography.
Intense pink and purple - likely to the cause of intense solar activity and storms, largely pink aurora can be fairly rare.
Light haze - sometimes there's a faint haze, particularly early in the formation of the aurora. This has less of a colour and more of a gradual increase in intensity leads to , however, whilst sometimes these colours do not intensify, they may look better on camera.
There are occasional pulses of light that are not particularly colourful but cause a ripple of activity across the sky. Quite spectacular even if not as intense as the usual colourful aurora.
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