Forget Fifty Shades of Grey, what gets us Aurora hunters all steamed up are myriad shades of green.
Green is the predominant colour in the Northern Lights and whilst the science that determines the colours in the Northern Lights isn't quite as racy as E. L. James's erotic romance novel, it's worth looking at what causes the Auroral colours.
When charged particles from the sun collide with the atoms and molecules that constitute the gases in the Earth's atmosphere those atoms are said to be "excited" and as a result, they give off light. The colour of that light is determined by the type of gas involved in the collision.
Are you still with us? Bet you read Fifty Shades of Grey for longer than you did this blog!
Most commonly, the sun's particles hit our atmosphere at altitudes between 75 miles and 120 miles where Oxygen predominates. When the atoms in Oxygen are "excited" they give off green light and hence, the majority of Auroral displays are different shades of swirling, twirling, shimmering, dancing green light.
Sometimes, when the Aurora is really, really bright, it gives off enough light to read by. Perhaps you should take the book with you when you go searching for the Northern Lights but we're prepared to bet that you'll be far too distracted to read even a single page!
Read more about the Aurora Colours here.