We’ve had a number of aurora australis sightings in Melbourne in recent years, and if you can’t get enough of this cosmic show, you’re in luck. There’s a very good chance that the aurora australis will be visible tonight (Tuesday, January 20). The Australian Space Weather Forecasting Centre has issued an aurora alert, stating that there is a “severe geomagnetic storm in progress”. According to the NOAA Space Weather Prediction Center, this is also the “largest solar radiation storm in over 20 years”. When night falls, the aurora could be visible in the southern parts of Australia, including Melbourne. While it’s hard to predict exactly when and where you can see the Southern Lights, there are some things you can do to increase your chances.
Spotting aurora australis in Melbourne
Conditions for auroras are more likely when the sun is more active. During periods of increased solar activity, such as coronal mass ejections, dense plasma is thrown into the solar wind. These particles then interact with the Earth’s magnetic field, creating dancing displays of green, red and purple.
Recently, a powerful X-class solar flare launched a halo coronal mass ejection directly to Earth. The solar radiation storm has been classified as an S4, and conditions like this have not been observed since October 2003. The coronal mass ejection triggered the severe geomagnetic storm conditions. If there’s no clouds tonight, there’s a very strong chance you’ll see a spectacular display of the Southern Lights.
You can keep an eye on conditions by looking at handy websites like the Australian Space Weather Forecasting Centre or Space Weather Live. You can also join Facebook groups, like Aurora Hunters Victoria, for local information and updates.
To see the Southern Lights, you’ll need to rug up, then find somewhere dark with a view to the south. Looking out over the ocean is a particularly good plan, because it’s flat and you don’t have to worry about light pollution getting in the way. But, if you can’t make it to the coast, you can still see the aurora inland, as long as there aren’t any obstructions like mountains or buildings blocking the view.
Allow time for your eyes to adjust to the darkness. This can range from ten to twenty minutes. You’ll also need to adjust your expectations, because what your eyes see and what your camera sees are different. While you might be expecting vivid colours of greens and reds, the naked eye will more likely see moments of brightness, like a flickering white light. Cameras, which have a longer exposure, can pick up the colours to create the spectacular photos you’re more familiar with. When the particles interact with oxygen in our atmosphere, they give off a green and red light, whereas nitrogen creates gorgeous hues of blue and purple.
Keep in mind that this is a natural phenomenon, and sightings aren’t guaranteed.