TECH
15/05/2014 06:00 BST

What Causes Lightning? Scientists Claim Solar Particles Are The Trigger

Solent News

Lightning has long puzzled scientists.

A consensus agrees that it is caused by ice particles in clouds colliding to form an electrical charge but just how this charge reaches the earth has been a mystery.

A team of British brains believe they may now have the answer and it is actually the sun that is responsible.

lightning

Beautiful but often deadly

They theorise that high-energy particles, the solar wind, charge the air in the atmosphere creating a pathway through which a bolt can travel.

The particles, which can travel at around a million miles per hour, can also come from further afield, expelled from exploding stars far away in the universe.

Because the sun is constantly observed by a fleet of Nasa spacecraft called the Solar Dynamics Observatory (SDO), it should be possible to predict when increase in lightning are likely to occur.

An estimated 24,000 people are killed every year by lightning strikes - not to mention numerous livestock - so this vital information could go some way to reducing this.

Lead researcher Dr Chris Scott, from the University of Reading, told the BBC: "Lightning represents a significant hazard.

"Having any understanding or advanced warning of the severity of lightning storms has to be useful.

"The solar wind is not continuous, it has slow and fast streams. Because the Sun rotates, these streams can be sent out behind each other - so if you have a fast solar wind catching up with a slow solar wind, it causes a concentration to occur."

Previously it had been thought solar particles would have the opposite effect on the frequency of lightning strikes by providing a shielding effect in the Earth's atmosphere.

Scott said: "Instead what we actually saw was a marked increase in lightning. It turns out these solar winds bring with them a slightly lower energy population of particle - and these are enhancing the lighting rate."

Last month scientists announced they had developed a new type of laser that essentially recreates the effect of solar particles and could be used to divert strikes away from buildings for instance.