There was a rainbow-like shimmer above the Ballarat airport, and the sky glowed hot pink in Busselton, Western Australia.
In the small hours of Monday morning, there were reports of aurora australis sightings from Tasmania to Canberra, across Victoria, and all the way west.
A geomagnetic storm on the sun had sent particles streaming towards Earth, where they hit the atmosphere and caused the luminous display. Auroras are more commonly seen at the north and south poles, but a fierce eruption from the sun’s surface can drive the spectacular phenomenon closer to the equator.
Dr Brad Tucker, an astrophysicist at Australian National University, said the bigger the storm, the more energy is released, and the more visible the aurora becomes.
“You have some sort of eruption – a coronal mass ejection – where the sun ejects its plasma stuff and it travels into space,” he said.
“The electromagnetically charged plasma slams into the Earth’s atmosphere [and] it excites the gas in our own atmosphere, kind of like a neon sign. You get a gas and put a charge through it and it causes the electronics to glow.
“That’s pretty much what’s happening.”
The same eruption saw aurora borealis in the northern hemisphere, including a ghostly pink haze over Stonehenge.
The Bureau of Meteorology put out an aurora alert on Monday morning.
“Geomagnetic storm in progress. Aurora may be observed during local night-time hours in good observing conditions at high latitudes,” it said. The BoM recommends aspiring aurora observers find somewhere dark, with no light pollution and a clear view to the south between 10pm and 2am.
When the sun’s activity is low, aurora australia can be seen in Antarctica and southern Tasmania. A severe sun storm can mean it is visible in Queensland.
Tucker said aurora follow the 11-year solar cycle, which is now in its maximum stage.
“So that’s why people are seeing it quite a lot this year, we’re in the solar maxima, and it’ll last for another year or two, so you can expect more of them to come to Australia,” he said.
Increased sightings could also be due to better technology and communication, he said.
“Our equipment from the last maxima, is a lot better, a lot more accessible,” he said.
“People are capturing it on their mobile phone, that’s where you get the colour.
“It is visible to the naked eye. But more vivid colours, definitely that is a factor as well, people are noticing it on social media, they’re joining aurora groups.”