Aurora borealis shines in UK skies after geomagnetic storm
For the second night in a row, the Northern Lights shone across the United Kingdom.
With a solar storm strengthening, they were even – more unusually – seen as far south as Devon and Cornwall on Wednesday night.
It comes after a vibrant display was seen across Scotland on Tuesday.
The current solar storm has now weakened but with overall solar activity remaining high, more sightings in the coming weeks and months are possible.
shafts of purple light in the sky with greens and yellows of the aurora closer to the horizon
trees with purple shafts of light of the aurora in the night sky
Image caption, Weather Watchers in southern England and here in Pembrokeshire, South Wales were treated on Wednesday night
With a solar storm starting on Tuesday night, a strong aurora was initially seen across Scotland.
BBC Weather Watchers were able to capture a spectacular display with vivid purple and green colours filling the sky.
Throughout Wednesday afternoon there was an increase in solar energy entering Earth’s atmosphere, resulting in a strengthening of the aurora.
According to AuroraWatch UK, solar activity increased with “red alerts” being issued from 13:00 BST and persisting through the afternoon.
For the UK, had it not been during daylight hours, a spectacular Northern Lights display would have been seen.
However, red alerts persisted into the darker night with solar activity peaking at around 22:00 BST in a “severe geomagnetic storm”, reaching level four out of five on the geomagnetic storm scale.
With a storm this strong, the aurora was enhanced so much it could be seen across southern England.
Unfortunately for aurora watchers in Scotland, what would have been a spectacular display was spoiled by overcast skies.
bright purple and green of the aurora fills the night sky
What causes the Northern Lights?
There have been frequent sightings of the aurora in the UK over the last year.
The Sun is currently at a “maximum” in its 11-year solar cycle.
This means there are lots of sunspots on the surface which are like volcanoes and occasionally erupt. They are also known as Coronal Mass Ejections (CME’s) and release extra material and energy out to space.
If directed towards Earth, our magnetic field pulls the energy into Earth, entering our atmosphere at the poles.
purple hues in the sky of the aurora.
Will we see the Northern lights again?
The solar energy from the CME responsible for the aurora this week has now weakened.
Activity is therefore expected to remain fairly low over the next few nights.
However, according to the Met Office Space Weather forecast, fast solar winds are likely on 20 April with “active” intervals possible.
Beyond the short term, with the Sun only gradually weakening over the next few years from its maximum, there will still be plenty of activity through 2025.
However, as the northern hemisphere heads towards summer with increasing daylight hours, viewing opportunities will be more limited.
