Extract from ABC News
If you are anywhere north of Brisbane, you might be lucky enough to catch a meteor streaking across the sky in the early hours of tomorrow morning.
Key points:
- Only people in northern Australia will be able to catch a glimpse of the Perseid meteor shower
- It is expected to peak just before dawn on Friday morning
- Australia will have a better view of the Geminids meteor shower in mid-December
The Perseid shower, which shows up every August, is known for its bright and fast meteors caused by the Earth travelling through a trail of debris strewn across the solar system by a comet.
That event, lasting several weeks, is dubbed "one of the best meteor showers" in the Northern Hemisphere, where it has been known to produce 100 meteors an hour.
However, University of Southern Queensland professor of astrophysics, Jonti Horner said the rate would be much lower here.
"For us here in Australia, we don't get a very good show because the place in the sky the meteors are coming from stays very low to the horizon and that means we just don't get to see as many of them," Professor Horner said.
"But it's certainly well worth looking out for if you're out and about anyway, or if you're particularly enthusiastic."
The International Meteor Organisation predicted the shower would peak just before dawn on Friday morning, but Professor Horner said Cairns residents could start seeing meteors around 2:00am.
Professor Horner said the meteor shower would be visible above the northern horizon.
Queenslanders living further south than Cairns may be able to see the meteor shower an hour or two before dawn.
"But don't expect incredible fireworks where there are flashes of light all the time."
The further north you are, the better chance you will have of seeing some action.
"If you're as far north as Cairns, in the hour or two before sunrise you might be lucky enough to see 15 or 20 meteors, shooting stars, per hour," he said.
"Exactly the same applies in the Northern Territory, and in the northern half of Western Australia.
"Darwin's rates would be comparable to, or slightly higher than Cairns, as Darwin is four degrees further north."
Professor Horner said as far south as Rockhampton the rate was reduced to 10 or 15 per hour.
"By the time you're as far south as Toowoomba, it's maybe 5 to 10 and if you're in Sydney or Melbourne, you don't see any at all," he said.
If you are in lockdown, or too far south, NASA will be livestreaming the peak of the shower.
Comet Swift-Tuttle
Outback astronomer Anthony Wesley said the shower was caused by the comet Swift-Tuttle.
"The comet is just a big lump of ice, fairly loosely held together," he said.
"When it comes into a part of the solar system where we happen to live, it gets heated up by the sun and a lot of the outer parts of it just break off.
"You get lots of little pieces of rock and ice and grains of sand that just get warmed up by the heat and left behind as the comet turns around and heads back out again.
The Rubyvale astronomer said the tiny meteors were "no more than a millimetre or two" big.
"It takes something seriously large, like a few centimetres across, to make a really bright fireball in the sky," Mr Wesley said.
He said some meteors could survive the heat of re-entry into the Earth's atmosphere.
"The Earth picks up hundreds of tonnes of just dust from space every day," he said.
"It's quite common for people who live in high-rise buildings to be able to go onto their roof, if you've got a football-pitch-sized roof say, there's a chance you'd find a few little spicks and specks that had fallen out of the sky."
When can you see a better show?
Professor Horner said his favourite show, the Geminids shower, was due to arrive in December.
"The Geminids give better numbers than the Perseids anyway, but it's also higher in the sky so you also see better numbers," he said.
"This year the Moon does interfere and that'll lower things back down a bit but it's still fairly good.
"That's on the night of the 14th of December into the morning of the 15th, so it's like a little bit of a Christmas treat."
Professor Horner urged stargazers to keep an eye on local media rather than international media when it came to astronomy and meteor showers.
Professor Horner said there was an overlap, depending on how close you were to the equator.
"But there's a real risk with just trusting blindly an article that you find on the internet because it's from a really reputable source, like the BBC, because it's not written for you as a target audience," he said.
"The facts might not be the same."
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