Earth braced for more solar storms this week as radio blackout hits

On Monday, a huge solar flare erupted from the Sun (Picture: Nasa)

Get ready for another bout of epic space weather. The mega sunspot group that pummelled Earth with solar radiation earlier this month is on its way back – and could bring more aurora and radio blackouts with it.

Known as AR3664 to its friends, the huddle of spots on the Sun’s surface fired powerful solar flares our way, resulting in dazzling aurora across the UK and Ireland on May 9.

A week later, things got even wilder as AR3664 sent out the strongest solar flare of the current 11-year solar cycle, officially classed as an X8.7-class flare. 

However, the Sun is slowly spinning, taking 27 Earth days to complete one full rotation. This means shortly after that monster flare, the sunspot group turned away from the planet.

But they’ll soon be back – and seem just as angry as before.

On Monday, another X-class flare was seen erupting from the Sun’s southeastern limb, just beyond where the surface is visible from Earth.

While not yet in view, scientists are tracking the sunspots, and a map available on spaceweather.com suggests AR3664 was the culprit.

However, because they have been hidden for two weeks, there’s no way to be 100% sure – and so will be given a new name, as is the case for all sunspots when they roam into view.

But whether it’s AR3664 or not, we know it’s feisty. 

The Northern Lights, officially known as the aurora borealis, over St Mary’s lighthouse in Whitley Bay (Picture: PA)

The Aurora Borealis, also known as the northern lights, put on a show over Bingham, Nottingham (Picture: Alamy)

Solar flares fall into one of five categories – A, B, C, M and X, with X being the largest. Each class is then graded on a scale of one to nine. So this month’s X8.7 flare was almost as strong as they come, while an A1.2 is little more than a solar hiccup.

Monday’s flare was an X2.9, and was so powerful it caused shortwave radio blackouts in East Asia.

Solar flares are massive bursts of radiation from the electromagnetic spectrum, including X-rays and UV radiation. When they smash into Earth, they give an electrical charge to particles in the atmosphere, getting them all excited and sending them zooming around. 

This makes it harder for shortwave radio signals to travel through the ionosphere, because they keep bashing into them, scrambling the signals or absorbing them completely.

But it is also this phenomenon that helps create the aurora borealis, or Northern Lights.

The Northern Lights over Crosby beach, Liverpool (Picture: Peter Byrne/PA Wire)

A view of the lights at Minster on Sea, Kent (Picture: Alamy)

Alongside solar flares, sunspots can also emit coronal mass ejections (CEMs), huge burps of solar plasma, as happened on Monday.

While solar flares travel at the speed of light – taking just eight minutes to arrive – CEMs travel much solar, taking a few days.

Nasa projections suggest the most recent CEM isn’t heading our way. But the next one might.

As the sunspots turn into view, and with the Sun close to its solar maximum – the most active period during its cycle – we can expect more solar fireworks.

UK stargazers were wowed when the earlier flares hit, with the Northern Lights, or aurora borealis, shimmering across the country, which was largely blessed with clear skies.