Australia and New Zealand recently got a surprise light show, and some stunning images are showing up online.
When it comes to coloured lights in the sky, we hear a lot more about the Northern Lights than we do about their Southern counterpart, but that’s probably just because there are more people up there. If anything, the Southern Lights might even be more beautiful.
Chances are if you ask someone to give the technical names of these phenomena, they’ll mutter something about aurora borealis, the proper name for the Northern Lights, which have been immortalised in the lyrics of a famous Neil Young song. But how many would know the proper name of the Southern Lights, aurora australis?
That’s right: one of the most beautiful natural phenomena in the night sky is named after Australia. And a particularly spectacular display of these lights recently lit up the skies of Tasmania and New Zealand.
Social media users were eager to share their pics of the display, so if you’ve never had the chance to look at the aurora australis, don’t worry, we’ve got you covered:
— Anne-Marie (@AnneMarie224) May 28, 2017
— Ian Griffin (@iangriffin) May 28, 2017
— Chris Hibberd (@chrisanddannz) May 28, 2017
So wait, what exactly are these things again? And if the night sky can light up like that, why doesn’t it do it all the time? Well, for those of you who can’t remember the answer from your basic science class, the answer is that aurora phenomena, whether borealis (Northern) or australis (Southern) occur only under certain conditions.
The key ingredient is something called solar wind, which is the name given to the enormous streams of protons and electrons that are periodically emitted by the sun:
Solar wind varies in intensity, but when Earth takes a particularly big hit of the stuff, the intensity crosses a threshold, above which it has certain observable effects on Earth’s magnetosphere. Because most solar wind particles are charged, dumping a lot of them on top of the magnetosphere leads to a huge amount of particles being absorbed over a short time, losing much of their energy.
And humans have always been fascinated by on of the most noticeable side effects of that energy transfer: the intense, coloured light patterns that result. And in case you’re wondering why these phenomena are seen in the far South and the far North, but usually nowhere else, think about magnets and magnetic poles. Earth’s magnetic poles are at the most northerly and southerly extremities of the planet. And this is precisely where the magnetosphere tends to absorb solar wind particles.
But enough with the science for now. The beautiful thing about aurora phenomena is that everyone can appreciate them on an aesthetic level, even with no knowledge of or interest in the underlying science. So as interesting as it is to know about how this stuff works, let’s end this with a few more pictures of recent night skies over Australia and New Zealand.
And if you really want to see these tonight, close your laptop, turn off your phone, go outside, and look up. You never know when they’ll appear.
— Vince Taskunas (@VinceTaskunas) May 28, 2017
— Catherine Cavallo (@CavalloDelMare) May 28, 2017