< Back to 68k.news US front page

Friday night Australian east coast solar storm could lead to spectacular light show

Original source (on modern site) | Article images: [1]

A massive solar storm, set to peak on Friday night, could lead to a spectacular light show across Australia's eastern coast.

But scientists have also warned the opening of an enormous coronal hole on the sun could could cause power and GPS disruptions as charged particles stream towards the Earth.

The unexpected event started on Thursday night and its effects are expected to be felt on Friday night, with visible auroras possible in Tasmania and Victoria.

In 1989, a solar storm sent satellites tumbling from orbit and plunged the entire province of Quebec, Canada, into darkness.

Solar and stellar physics expert, Dr Hannah Schunker, said the world had become "a lot more reliant on technology and power since then".

"So we just don't know the full impact of what a huge solar storm could be these days," the University of Newcastle physicist said.

"They can generate currents that can interfere with electronics. This can mean anything from interfering with satellites in orbit around the Earth, down to affecting power lines on the surface.

"If the storm is very strong, it can interfere with your power, it could completely take out a power system, so there'd be a localised blackout, if there was enough damage at a power station."

The Australian Space Weather Forecasting Centre said increased geomagnetic activity was expected "due to coronal hole high speed wind stream". The activity reached G3 globally and G2 in Australia, although a G3 storm level is "possible", according to the centre.

At G2 (moderate) and G3 (strong), storms can disrupt satellite orbits and impact services. They can also affect radio frequencies and force the Australian Energy Market Operator to fix transmission outages. At G2 and G3, the centre says, "aurora sightings from dark sky locations in southern Australia are very likely, including Tasmania and southern Victoria".

If a storm reached G4 (severe) or G5 (extreme), the GPS would go down, satellites would be destroyed, aircraft could be affected and auroras would be visible as far north as Sydney, Perth and southern Queensland.

Schunker said the sun's magnetic field is on an 11-year cycle and is now heading towards its most active period.

skip past newsletter promotion

"The solar wind is always there, with particles streaming out from the sun, and sometimes those streams can get stronger or there can be an outburst, and this is what we call a storm," she said.

Those particles escape through a coronal hole in that magnetic field.

"A coronal hole appears visually as a dark region … it's cool, it doesn't release much light," Schunker said.

"The magnetic field that covers the sun is usually in an arc-like structure … in a coronal hole, these arches or loops have opened up, so they're streaming directly away from the sun … these particles are then able to escape.

"It's come loose. All sorts of things are blowing out from the tent. And this one's directed towards Earth."

As those charged particles hit Earth's magnetosphere, they create the auroras that are usually only seen closer to the poles. All that energy and those streams of particles mean auroras closer to the equator are possible.

Three weeks ago, intense solar activity created aurora australis that were visible from Tasmania and as far north as New South Wales.

< Back to 68k.news US front page