Following a recent large geomagnetic storm on the sun, a possible display of the Northern Lights can be expected across Wales over the coming nights. It is a phenomenon known in Welsh as 'Ffagl yr Arth' (the bear's firebrand). 

Whilst northern areas are favoured to see a display, it is possible that the lights - the Aurora Borealis - could also be seen across more southerly parts.

The solar flare, (or coronal mass ejection - CME), responsible for the possible display of lights, was observed on Saturday October 9 on the side of the sun directly facing the Earth.

The energy from the flare has been travelling from the sun over the past few days on the solar wind toward the Earth where it will interact with the planet's atmosphere causing it to fluoresce in an array of colours. The bright colours we see are dictated by the chemicals in the Earth's atmosphere.

The flare's energized particles will strike the Earth's upper atmosphere at speeds of up to 45 million mph and as they do so, the planet's magnetic field redirects the particles to the North Pole, hence the greater possibility of seeing the northern lights the further north you reside. 

After dark, gaze skyward to the northern horizon.

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