December 2015 Skynotes: Aurora

The outer layer of the sun, called the corona, it is continuously expanding and throwing out charged particles into space called Plasma – this is called the Solar Wind. Occasionally there are eruptions on the Sun in the form of Coronal Mass Ejections CME when large amounts of Plasma are thrown out in to space.

If the Earth is in way of one of these  CME then the charged particles interact with the Earth's magnetic field and they are drawn to the poles. The larger the CME the larger the the Aurora light display and the further south that it can be seen.

Big displays can be seen over a number of nights but you need a certain amount of luck to see a them, as individual displays may only last a few minutes. They can be repeated over the night.

If you are lucky enough to see them then they are normally quite feint - you will see large areas of colour, probably green or red, in the direction due north.

This is a short video made from single images taken with a Canon 1000d DSLR camera and a 18mm lens and tripod. Taken looking North over my observatory in Eynsham near Oxford.

Video taken at 10pm on 20-12-2015.

Matt Armitage


You can sign up for alerts whan the aurora is visible in the UK here.