Extract from ABC News
If you're up and about an hour before sunrise this week you may catch a 'shooting star' if you're lucky when the annual Orionids meteor shower peaks this week.
"The best time to see it is [Thursday morning] the 22nd, but you'll see decent meteor rates on the 21st and 23rd," says amateur astronomer Ian Musgrave.
And while you're waiting to see a meteor, you can get to know some of the most iconic constellations in our sky.
The Orionids meteor shower is caused by Earth passing through the dust stream of Halley's comet, the same comet that is responsible for the Eta Aquarids meteor shower.
The meteors come out from a point in the constellation of Orion above the northern horizon.
The best time to see it is between 4:00am and 5:00am.
You can see it from anywhere in Australia, but the further north you are, the better.
It's not as spectacular as the Eta Aquarids that occur earlier in the year, or the Geminids we see later in the year, but you should see at least 13 meteors at the peak if you are in a dark area.
How do I find the Orionids in the sky?
To find the Orionids, scan the northern sky and look for the 'Saucepan'.
The three stars in a line that make up the base of the Saucepan are actually the belt of the constellation of Orion.
In Greek mythology Orion is a hunter and many Australian Indigenous people also view this constellation as a hunter or a group of young men.
"Some [Aboriginal communities] see the upper body of a male throwing a spear with an arrow," says Karlie Noon, a Gamilaraay woman and astronomy ambassador for Sydney Observatory.
The meteors will come out from a point below Orion's belt near a big orange star called Betelgeuse, which is the hunter's shoulder, and shoot up through the belt.
Where is the best place to see it in Australia?
Just how many meteors you see will depend upon where you live.
The further north you are, the more you will see because the point at which they come out from will be higher in the sky (so there will be less atmospheric interference, and fewer meteors will disappear below the horizon).
| Location | October 21 | October 22 | October 23 |
|---|---|---|---|
| Adelaide | 12/hr | 16/hr | 12/hr |
| Brisbane | 13/hr | 18/hr | 14/hr |
| Canberra | 12/hr | 15/hr | 12/hr |
| Darwin | 18/hr | 22/hr | 19/hr |
| Hobart | 9/hr | 13/hr | 10/hr |
| Melbourne | 11/hr | 14/hr | 11/hr |
| Perth | 13/hr | 17/hr | 13/hr |
| Sydney | 12/hr | 16/hr | 13/hr |
If you are very lucky, you may even see a meteor shooting in from the left from the neighbouring constellation of Taurus.
The southern Taurid meteor shower (formed out of debris from Comet Encke) peaked on October 10 but runs right through the month, says Jonti Horner, an astronomer at the University of Southern Queensland.
However, the rates are much lower than the Orionids — only two meteors an hour at the peak wherever you live in Australia.
Even though the rates are very low, Taurid meteors tend to be brighter than Orionid meteors, says Professor Horner.
"If it's moving quickly, it's an Orionid meteor, if it's moving slowly it's a Taurid," he says.
While you're outside, check out Orion, Taurus and the Seven Sisters
To spot a meteor you need to let your eyes adjust to the dark, then scan the broad patch of sky where they appear.
Catching a meteor is a bit like catching a bus — you may need to wait for a while, then several may come at once.
While you are waiting, see if you can spot some of the gems in Orion and Taurus.
Many of the stars in these constellations feature in Indigenous stories across Australia, especially a group of stars in Taurus called the Pleiades or Seven Sisters.
The universal theme depicts Orion chasing the Sisters reflecting how the constellations move across the sky.
"With my mob, Gamilaraay mob, there's easily six or seven stories to do with the Pleiades," Ms Noon says.
"One of the stories talks about how the hunter (Birray-Birray) started chasing the sisters (Miyay-Miyay) ... and they ran up into a tree and they sang out to the creator and asked to be saved from the hunter.
"The sisters were put into the sky but a few years later the hunter became so powerful within the young men's group that he was also immortalised and put up into the sky and was able to continue his pursuit of the women."
Other stories explain why one star can be hard to see (one of the sisters is shy) or are linked with the seasons and time of year the group of stars start to appear above the horizon in the evening sky.
At this time of the year you can see the Seven Sisters after 11:00pm but both constellations aren't fully visible until just after midnight.
By 4:00am they are high in the sky.
If you find it hard to spot them above the northern horizon, use the stars in Orion and Taurus as guides.
Start with Betelgeuse below Orion's belt (the bottom of the Saucepan) then follow a line to your left past another bright orange star called Aldebaran, the 'eye' of Taurus.
Aldebaran also plays a role in the Orion-Seven Sisters story in the Kokatha language of the Great Victoria Desert.
In this story, the eldest sister Kambugudha (represented by the beautiful v-shaped Hyades cluster in Taurus) is trying to protect the Yugarilya sisters from Nyeeruna (Orion).
Nyeeruna throws fire magic towards her from his right hand (Betelgeuse), while she retaliates by kicking magic back at him from her left foot (Aldebaran).
"What's similar about these stars is that they are both variable stars so they both brighten and dim over time," Ms Noon explains.
"Again, you have that layer of scientific observation embedded in that narrative."
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