On Sunday the Met said the best chances to see the northern lights, also known as aurora borealis, were in Scotland, but “it could be possible as far south as central Wales and England”.
Professor Don Pollacco, department of physics at the University of Warwick, said the phenomenon was caused by “the interaction of particles coming from the sun, the solar wind, with the Earth’s atmosphere – channelled to the polar regions by the Earth’s magnetic field.
“It’s actually a bit like iron filings and the field of a bar magnetic.
“The solar wind contains more particles when there are sun spots, as these are regions on the sun’s surface where the magnetic field is interacting with the plasma in the sun, and the particles can be released.
“Once the particles are channelled into the Earth’s atmosphere they interact with molecules and have distinctive colours (eg oxygen molecules produce green light, nitrogen red light etc) and patterns such as light emissions that look like curtains or spotlights.
“These shapes change quickly over timescales of minutes/seconds.”