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How the dazzling lights of the aurora australis and borealis were captured in each hemisphere.
Striking hues of green, pink, red and yellow have transformed the world's skies over the past three days.
The phenomenon, known as aurora australis in the southern hemisphere, and borealis in the northern hemisphere, was triggered by the first extreme geomagnetic storm in 20 years.
From Friday to Sunday, the world got to witness the most spectacular show of northern and southern lights many have ever seen.
A 'crescendo' of solar activity
It all started with a rare "confluence" of solar activity, says Monash University astronomer Michael Brown.
The sun is currently near its maximum in its natural 11-year magnetic field cycle.
But over the past week, a large cluster of sunspots, estimated to be 15 times wider than the Earth, also popped up and began producing solar flares.
On Wednesday and Thursday, sunspots emitted four coronal mass ejections.
These are large expulsions of plasma and magnetic fields that can travel outward at speeds ranging from slower than 250 kilometres per second (km/s) to as fast as 3,000km/s, according to the US National Oceanic and Atmospheric Administration (NOAA).
The result was a "crescendo here on earth" as those combined forces hit the Earth's upper atmosphere over the weekend, Dr Brown says.
He watched the aurora from his home in suburban Melbourne before driving an hour south to Victoria's Cape Schanck.
There he joined thousands of other sightseers in capturing the sight.
"It was one of the most amazing astronomical sights I've ever seen," Dr Brown said.
Adding to the significance of the light show was just how far it travelled, with Australian sightings coming in as far north as Queensland's Mackay region.
Globally, the aurora was seen in previously unheard-of places such as northern Italy and the US state of Mississippi.
"Auroras happen a lot of the time, and in the polar regions they're very common," Dr Brown said.
"But to see auroras further and further from the pole gets rarer, and in Queensland, it's exceptionally rare to see auroras that far.
"In fact, it's entirely possible it hasn't been seen in 50 years."
With a history of "over hyping astronomical events," Dr Brown believes initial reports were cautious.
Instead, the display we got was "ludicrous" he says.
Some experts have already started comparing it to one of the most intense geomagnetic storms in recorded history, back in 1938.
While Dr Brown says it will take a while to scope its full magnitude, one thing about this weekend's solar event is for sure.
"It's certainly one of the biggest aurora displays for decades," he says.
Photographers in awe
Photographers and amateurs were quick to capture the stunning show of colours.
In Australia, clear skies meant stargazers caught some amazing snaps.
But the colours varied depending on where you were, as Karl Kruszelnicki explains.
"At high altitudes you get the oxygen giving you a bluey colour. At lower altitudes more of a reddy colour," he told ABC News Breakfast.
On Saturday night in a paddock in the small South Australian town of Wudianna, Kristy Sampson rushed to the paddock with her camera.
The sky above was bathed in pinks and purples.
She had never seen anything like it.
"I thought, 'how awesome', I really didn't expect it to be that clear," she said.
"It was just stunning to be able to see this."
Photographer Sandy Horne drove around north of Adelaide on Saturday night searching for the perfect shot.
"Driving along, I could see the sky full of light and beams and quickly pulled over for more pics between Eudunda and Truro," she said.
"I haven't enhanced the colour of any of my photos.
"They are just naturally ridiculous."
"I've seen things tonight that have blown my mind," Simon Gregory from Southern Tasmania added.
The southern lights were also seen in Latin America, where people in Chile and Argentina witnessed dazzling displays of red and magenta.
Northern hemisphere bathed in colour
In the northern hemisphere, time-lapses captured the light.
It danced across the sky from Europe to the United States, Central America and Asia.
In China, tourists flocked to the north to see the lights.
One tourist, Ma Jingxuan, said he drove from Beijing to Mohe which is a 25-hour journey.
"It was red with pink colours, and the lights were swaying left and right," he said.
"It was very nice and stunning."
In Canada, some were lucky to see the International Space Station streak across the sky at the same time.
While there were some fears for the astronauts onboard, NASA confirmed the weather was "no risk" to the crew and no additional precautions were taken.
In Europe, the sky glowed on Saturday in Switzerland, Poland, Czechia, Spain and Germany.
Britons watched the solar flares dance along the coastline.
In the US, residents in Washington, California, Colorado, Missouri, Virginia, Maine and Oregon all caught a glimpse.
NOAA Space Weather Prediction Center scientist Rob Steenburgh said the show was one to behold.
"That's really the gift from space weather: the aurora," he said.
While there may be more auroras over the coming days and months, Dr Brown said he would be "pleasantly surprised" to see it match this weekend's international performance.
For those eager to keep a lookout, he encouraged stargazers to check out NOAA's 30-minute prediction website or local aurora hunter Facebook groups.
Credits:
Images: AP, Reuters and supplied
Words and production: Tessa Flemming, Georgie Hewson and Basel Hindeleh