coronal

The heightened chance of a UK sighting has been caused by a fast-moving coronal mass ejection, which is a "release of plasma and magnetic field from the Sun's corona", late on Saturday night.

The most vivid auroras occur when the Sun emits large clouds of particles called coronal mass ejections.

During this phase there is an increase in the number of eruptions from the Sun, including solar flares and coronal mass ejections.

But solar storms, solar flares and coronal mass ejections routinely impact Earth's weather.

This time around there is only one coronal mass ejection and experts believe the duration of the event will be much shorter.