Weird world of lightning strikes reveals nuclear fusion bursts in the sky

23 Nov 2017

Image: laptopnet/Shutterstock

A new study into what occurs during a lightning strike has given fascinating insight into some powerful forms of energy.

The next time you find yourself terrified or thrilled during a lightning storm, it’s worth bearing in mind that some advanced particle physics is occurring just above your head.

In a paper recently published to the journal Nature, a team of researchers from Japan revealed that a powerful lightning strike can warp the air around it to incur a nuclear fusion reaction.

Nuclear fusion is most commonly seen in the centre of our own sun, with temperatures of around 16m degrees Celsius. Many attempts have been made here on Earth to harness it to create a source of clean, near-limitless energy.

Flashing lights

When lightning strikes, a series of reactions known as gamma-ray flashes occur and, in fact, the team recorded three distinct gamma-ray bursts.

The first was less than one millisecond in duration, the second was a gamma-ray afterglow that diminished over several dozens of milliseconds and, lastly, there was a prolonged emission of about one minute.

These flashes are so powerful that they are able to break apart nuclei of nitrogen and oxygen to remove the neutrons, resulting in a fleeting radioactive reaction.

However, the flashes were so dazzling that the team’s instruments were not able to record their brightness.

Questions remain

Many other questions are left unanswered by the discovery, such as: how exactly do these gamma-ray flashes occur in lightning storms?

Based on our current understanding, it should be impossible for fusion reactions to occur because the fuel that drives them – a form of hydrogen called deuterium – is nowhere near as abundant in our atmosphere as in the sun.

While much more research needs to be conducted to answer such questions, the team believes that its findings are a major step in the right direction to understanding the phenomenon.

“We have this idea that antimatter is something that only exists in science fiction,” said Teruaki Enoto, lead researcher on the project. “Who knew that it could be passing right above our heads on a stormy day?”

Colm Gorey was a senior journalist with Silicon Republic