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ABC News
2 days ago
- Climate
- ABC News
A peak in the solar cycle means we're getting spectacular aurora australis sightings — for now
We've been treated to some stunning aurora australis light displays over the past few days, but don't expect the glow to last forever. The Sun's 11-year cycle means we're currently in the midst of an explosion of aurora activity. But that'll simmer down soon. It's a phenomenon when the sky in the Southern Hemisphere is lit up by glowing whirls of colour. You'll also hear it referred to as the southern lights. "Australis" comes from the Latin word for "southern". In the Northern Hemisphere, it's called the aurora borealis, or the northern lights. Geomagnetic storms. It's triggered by something called coronal mass ejections. "A coronal mass ejection is the literal ejection of material from the Sun out into space," Australian Space Weather Forecasting Centre (ASWFC) forecaster Andrew Jackling says. This sends charged particles from the Sun towards Earth, causing geomagnetic storms that can disrupt Earth's magnetic field. "Kind of like in a normal thunderstorm, your shutters on your house would get a bit rattled by the wind and the rain," he said. In a geomagnetic storm, the disruption can cause atoms of oxygen and nitrogen in the atmosphere to emit bright, colourful light. "There was a large solar storm on the 31st of May," Australian National University astrophysicist Brad Tucker says. "The storm was large enough to trigger a G4 storm on Earth. "The scale is 1-5, like cyclones, with G5 the largest." Here are some of the latest photos, posted to the ABC's Weather Obsessed Facebook group: While auroras are usually limited to the southernmost parts of the country, there were sightings as far north as Tamworth in New South Wales. And a big part of this is because of where we are in the solar cycle, which goes for roughly 11 years. "The current solar cycle began in 2019, since which time solar activity has generally increased as the Sun progresses toward solar maximum, which officially began in October 2024," Mr Jackling says. And that means spectacular auroras. "During solar maxima, which we are at, the Sun produces more storms, and more extreme storms," Dr Tucker says. "The activity is stronger so it is producing more of these." But it's not just the individual storm from the past few days. We've had some fairly spectacular aurora displays over the past year — check out the ABC's collection of photos from January, October, September and last July. However, the most notable aurora displays happened in May 2024, when a G5 storm hit Earth. It was the biggest geomagnetic storm we'd seen in 20 years, NASA says. While it didn't cause any catastrophic damages, the event was so big it was given a name — Gannon storm — and was the subject of a big NASA study. The solar maximum may continue for another year or two, Mr Jackling says. "By 2027, solar activity is likely to have reduced from present levels, making geomagnetic storms and subsequent auroral displays less likely to occur," he says. However, it's hard to tell exactly how long the aurora boom will last. "Every 11-year period of maximum activity varies in strength," Dr Tucker says. "Just like summers vary in how hot they are, or how wet/cold winters are, same, with the Sun, so some periods are better and others are less. "This has been a good period." No, they could still happen. "Significant space weather can occur at other times in the cycle too," Mr Jackling says. However, aurora australis activity during this time might not be visible as far north as we've been enjoying lately. So aurora chasers may have to travel much further south. "There is still an often low level of activity in the quiet years that you can get, but you need to be very near the south or north pole, which is why people make trips to the Arctic circle to see them," Dr Tucker says. Also, it's important to remember that the solar cycle means we'll come back around to another solar maximum — we'll just have to wait about a decade. Yep. "The northern and southern lights are affected equally so they will reduce as well," Dr Tucker says. However, people in the Northern Hemisphere have a better chance of seeing an aurora. "It is generally easier to see the northern lights than the southern lights due to the geographic distribution of land in the northern hemisphere, where there are more populated areas closer to the northern polar region," Mr Jackling says. "This is true at all times of the solar cycle." The ASWFC, which is part of the Bureau of Meteorology, sends out geomagnetic storm alerts via email. If you sign up to the ASWFC alerts via this online portal, you'll get an email when there's an alert.
The Independent
3 days ago
- Climate
- The Independent
Bright green meteor zooms past Sydney as auroras dazzle across Australia
A bright green meteor was seen zooming past Sydney on Sunday as spectacular southern lights lit up the skies across most of Australia and New Zealand. A Sydney resident named Tom McCallister posted a video of the meteor, about the size of a basketball, traversing the city's skies. 'Absolutely magnificent meteor seen travelling east to west over Sydney this evening,' Mr McCallister captioned the video posted on Facebook. 'This was looking north at 17:57 local time.' Astrophysicist Brad Tucker, from the Australian National University, agreed that the object was indeed a meteor due to its unique blue-green colour, indicative of iron and nickel content. People across New Zealand and on Australia 's east coast were also treated to a dazzling display of southern lights on Sunday. Many skygazers later shared photos of aurora australis on social media. The space weather phenomenon is caused when bursts of charged particles released from the Sun – known as coronal mass ejections, or CMEs – interact with the Earth's magnetic field, creating what's called a geomagnetic storm. The lights are called aurora australis in the southern hemisphere and aurora borealis in the northern hemisphere. Pictures posted on social media showed the sky glowing in hues of pink, red and green, with slight traces of yellow. The colours come from different molecules in the atmosphere getting charged by the Earth's magnetic field. Oxygen gives off a fluorescent green hue while nitrogen molecules interacting with the magnetic field generate a blue, red or pink shade. Auroras are seen when a strong solar storm from the Sun hits the Earth. They are more clearly visible around polar regions since the magnetic field is the strongest there. Astronomers have predicted a strong geomagnetic storm on Sunday and Monday after a powerful CME was seen erupting from the Sun on Friday. The latest CME also caused aurora borealis across most of the continental US as far down south as Alabama. The US National Oceanic and Atmospheric Administration said the possibility of a severe geomagnetic storm remained 'in effect'. 'There are indications that the coronal mass ejection passage is weakening, but the solar wind conditions remain elevated, therefore additional periods of G3-G4 levels remain possible,' the NOAA said, using the designations for strong and severe category storms. 'However, we now anticipate that conditions should weaken enough by tomorrow evening, 2 June, that G1 storm levels are the most likely peak response.' The Sun is currently at the peak of its 11-year activity cycle.
ABC News
3 days ago
- Climate
- ABC News
Aurora australis thrills light show chasers
Australian stargazers enjoyed a brilliant show Sunday night, with auroras illuminating the dark winter sky with pink and green hues. In areas as far north as Tamworth in New South Wales, clear skies aligned with a geomagnetic storm to show off a vibrant aurora australis that was visible to the naked eye. Astronomer Fred Watson said it was "quite unusual to see the aurora this far north", and that a particularly strong solar storm was behind its visibility. Auroras are caused by geomagnetic storms, which in turn, are triggered by ejections of material from the Sun into space. In a geomagnetic storm, atoms of oxygen and nitrogen in the atmosphere emit the bright, colourful lights that create auroras. "The more active the energy is, the closer to the equator it can be seen," Dr Watson said. Cressida Toorenburg was lucky enough to catch the light show in East Devonport, Tasmania after clouds parted overhead. "We sat for half an hour in the hope that the clouds would move away and then wow," she said. "There was Lady Aurora! It was breathtaking — you could see her with the naked eye, but much bigger and brighter through the screen on my phone." Ms Toorenburg said she has lived in the area for seven years and never seen an aurora as dazzling. "The colours were so beautiful and vibrant," she said. Separately, a meteor lit up Sydney skies about 6pm on Sunday. Australian National University astrophysicist Brad Tucker said Sunday's especially visible auroras were caused by a strong solar storm. "The bigger the storm that leaves the Sun, the more likely the aurora is to be on Earth and the stronger the aurora is," he said. He said aurora fans should get outside just after sunset Monday night for another chance to catch some colour. An updated geomagnetic warning published by the Australian Space Weather Forecasting Centre (ASWFC) says increased activity is expected to continue until June 3. Monday's forecast carries a G-scale rating of 4 out of 5, which indicates a higher chance of a light show. The ASWFC, which is part of the Bureau of Meteorology, sends out geomagnetic storm alerts via email. If you sign up to the ASWFC alerts via this online portal, you'll get an email when there's an alert. Here are some more stunning photos taken of the aurora overnight.
ABC News
3 days ago
- Climate
- ABC News
Meteor flashes through skies in Sydney as Aurora Australis seen across southern NSW
A bright flash of light that briefly lit up the Sydney sky on Sunday night was not a rogue Vivid installation but is believed to have been a meteor. Sydney resident Tom McCallister said he was waiting at traffic lights about 6pm when he saw the light appear in the sky. "I was luckily on the ball and had my phone to hand to quickly capture the last few seconds of its flight." Australian National University astrophysicist Brad Tucker said it was definitely a meteor as it flashed a blue-green colour and was travelling faster than space debris does when it is typically seen falling towards Earth. "Meteors have lots of iron and nickel, when it burns up in the Earth's atmosphere you get to see it as burning as a blue-green colour," Dr Tucker said. "It would have been a good-sized meteor, maybe anywhere between a tennis and basketball sized," Dr Tucker said. It capped off a busy week for star-gazers, who have been treated to clear views of the Aurora Australis on the east coast. Joe Cali captured the pink glow in the night sky from a property outside Young in the NSW Riverina region. "It put on an entertaining show for south eastern Australia for 6 hours from the end of twilight until around midnight," Mr Cali told 702 ABC Radio Sydney. "At its brightest a pink glow with some vertical pillars of light were visible to the naked eye. "For other parts of the night, the brightness reduced and you could only see it as a pale grey glow with my night vision." Dr Tucker said the especially visible auroras were down to a strong solar storm ejected from the sun hitting the Earth. "The bigger the storm that leaves the Sun, the more likely the aurora is to be on Earth and the stronger the aurora is," Dr Tucker said. Dr Tucker said the Sun was in the peak of a 11-year cycle of solar activity, leading to the stronger auroras that could be seen as far north as northern New South Wales. "This year and last year have been very active periods from the sun which is quite rare."
