Three large solar flares over the last two days have released a huge cloud of particles from the sun which could knock out satellites and communication systems on Earth.

A 'coronal mass ejection' (CME), a huge cloud of irradiated particles and a magnetic shockwave, could strike the planet on Friday, damaging satellites and knocking out communications.

The three solar flares already caused brief disruptions to high frequency communications, such as radio broadcasts and aircraft communications, when they struck yesterday and twice on Tuesday.

The sun emitted two X-grade solar flares on Tuesday morning at 7.42am and 8.52am - X being the most powerful kind of solar flare - and a third X-class flare early yesterday.

Solar flares are largely harmless, as Earth's atmosphere absorbs most of the harmful particles they emit. However they can cause satellites to malfunction, and disrupt the layer of atmosphere some communications pass through, causing interruptions.

Events on this scale are unlikely, as the NOAA says the CME due on Friday will only strike a 'glancing blow', but satellites could be affected, leading to a drop in mobile phone signal.

The last major CME to hit Earth came in 1859 when compasses were knocked out as Earth's magnetic field was disrupted. 

 

The Aurora Borealis was also visible as far south as Cuba as particles from the sun bounced off of Earth's atmosphere.

Because the last major CME happened before the planet was dependent on electronics for our day-to-day lives, little is known about what the real impact would be.

But it is likely that large electronics would be badly affected, causing weeks or months of disruptions to power supplies, phone networks and the internet which could cost billions to repair.

Small electronics, such as mobile phones and computers, would likely be unaffected, but would be rendered almost useless with large networks knocked out.