A stunning display of the Aurora Australis, or Southern Lights, captivated the skies over New Zealand and Australia on Wednesday, painting the horizon in vibrant hues of pink, violet, and green. This breathtaking spectacle was triggered by a 'cannibal' solar storm, a powerful geomagnetic event caused by bursts of solar energy colliding with Earth's magnetic field. The Bureau of Meteorology confirmed the storm reached G4 geomagnetic storm conditions, one of the highest categories on the intensity scale. Social media lit up with images from across the continent, stretching as far north as Port Macquarie in New South Wales, while New Zealanders were also treated to a rare auroral glow.
But here's where it gets controversial... The formation of this rare solar storm is a fascinating interplay of solar physics. When two coronal mass ejections (CMEs) - massive bursts of charged particles from the Sun - collided en route to Earth, they triggered the stunning phenomenon. Dr Laura Driessen from the Sydney Institute for Astronomy explained that a 'really strong and magnetically active sunspot' had released the CMEs on November 9 and 10, with the faster one catching up to the first. The second CME caught up with the first one and they amalgamated together by the time they reached Earth, hence the term 'cannibalized'.
The Northern Lights have also been shining brightly, with aurora borealis displays stretching as far south as Mexico and the northern United States. The US National Oceanic and Atmospheric Administration (NOAA) recorded one of the strongest solar storms of the year, describing it as a level 4 storm on a five-point scale. NOAA meteorologist Mike Bettwy explained that electrons released during these CMEs collide with atoms in Earth's atmosphere, creating the vivid curtains of light seen worldwide.
And this is the part most people miss... While the Aurora Australis put on a dazzling show, it's important to note that these solar storms carry risks. As per The Guardian, these events can generate electric fields capable of disrupting power grids and satellite systems. The surge in solar activity also prompted NASA and Blue Origin to postpone the launch of two Mars-bound spacecraft due to safety concerns. With the Sun now at its most active phase of its 11-year solar cycle, 9News quoted Dr Sarah Reeves of the Bureau of Meteorology saying, 'We've passed the peak of the geomagnetic activity now, but it's something we're monitoring constantly.'
So, if you missed the display, there may be another chance to see the Southern Lights tonight. The same geomagnetic storm could continue interacting with Earth's atmosphere, offering a second night of visibility. The Bureau of Meteorology anticipates the best viewing times to be between 8 pm and 8.30 pm AEST, especially in southern and coastal regions such as Victoria, South Australia, and Tasmania. However, as per Marie Claire, Dr Rebecca Allen from Swinburne's Space Technology and Industry Institute noted that tonight 'will most likely be the last chance to catch a glimpse,' as geomagnetic activity begins to decline. These things build up over a few days, and then they release.
For optimal viewing, experts suggest heading to dark, rural areas with a clear view of the southern horizon, such as beaches or rural areas. City lights can diminish the spectacle, while long-exposure photography can help capture the most vibrant hues. Auroras can appear visible up to 1,000 kilometres away, with vivid colours often best captured through long-exposure photography. While breathtaking, these solar storms carry risks, and it's crucial to stay informed and prepared.
