Extract from ABC News
While it might be tempting to stay home and rug up, winter is the best time of year to go out and see the night sky.
This year has been particularly chilly in the southern half of Australia, but if you head outside on a cold, clear night, you'll have an amazing view of our sparkling sky.
You may even see an emu too.
The darker the sky, the better — and this weekend should be particularly good as there's a new moon on Sunday, August 4, so there won't be any moonlight to disrupt your view on that night.
When you're out there, one of the most obvious and largest features we see from a dark area in winter is the thick band of stars that stretches across the sky, which is our galaxy, the Milky Way.
And at this time of the year it is jam-packed with some of the most stunning constellations, star clusters, and clouds of gas. This makes it the prime viewing time for astronomers such as Stefania Barsanti.
Dr Barsanti, from the Australian National University, uses the optical telescope at Siding Spring Observatory, a dark sky site near Coonabarabran.
"Some objects are only visible during a part of the year. So if you miss it, then you have to wait another year to do your science," she says.
"During the winter, these beautiful clusters of galaxies are visible.
"They are the biggest objects in the Universe."
Some features in our winter sky are only visible from the Southern Hemisphere, so Australia gets a front-row seat to the action.
But you don't need to be a professional astronomer to explore the wonders of winter.
Here's what to keep a look out for and how best to see it.
Constellations
At this time of the year, in the early evenings, the Southern Cross lies on its side, close to the southern horizon.
The five major stars are part of a larger constellation known as Crux.
If you're in a dark sky area, look carefully at the area near the brightest star in the crossbar of Crux (Mimosa) with binoculars or a small telescope. You'll see a pretty cluster of red and blue stars known as the Jewel Box.
Moving higher in the sky are "the pointers" in the constellation of Centaurus, and Alpha Centauri, the third-brightest star in the night sky and our closest stellar neighbour.
Moving deeper into the thick part of the Milky Way is the arching beauty of Scorpius (not to be confused with Scorpio the star sign).
Keep an eye out for Antares — the big red star at the heart of the scorpion — and trace down the curving line of stars that make up its tail. If you have binoculars or a telescope, this is where you'll also spot a group of sparklers known as the Butterfly Cluster or M6, which, as its name suggests, looks like a butterfly.
The thickest part of the Milky Way contains the heart of our galaxy, as well as constellations Sagittarius, Ophiuchus, and Serpens.
These constellations are home to beautiful gas clouds, such as Rho Ophichi and the Eagle Nebula (and the Pillars of Creation), which are favourites of astrophotographers.
"[It's always] a great time to look at the stars, because you're always going to see something," Kirsten Banks, an astrophysicist, science communicator and keen stargazer, says.
"But the winter night sky is definitely my personal favourite."
The Dark Emu
If you look carefully at the Milky Way from an area with no light pollution, you'll see the famous Indigenous constellation called the Emu in the Sky.
To spot its head and beak, look for the Southern Cross, says Dr Banks, who is a Wurundjeri woman.
Then continue along the band of the Milky Way, where the darker sections make up the neck and body in Scorpius.
"We call it Gugurmin. It's incredible. Once you see it, you can't unsee it," she says.
"It is a hugely vast constellation, and one that completely changes our understanding of what a constellation is, because it's not made of stars. It's made of the dark parts of the Milky Way galaxy."
Other galaxies
If you look just above the southern horizon at this time of year in dark-sky areas, you'll see two fluffy "clouds" with your naked eye.
These clouds, known as the Large and Small Magellanic Clouds, are not part of the Milky Way but are galaxies in their own right, some 163,000- and 199,000 light-years away respectively.
And you'll only see them from the Southern Hemisphere.
Planets and more
While the same constellations show up at the same time each year, you'll see different planets at different times depending upon their orbit around the Sun and how they align with ours.
The planets and the Moon move along the same path in the sky as the Sun, following an imaginary line known as the ecliptic.
"The planets are always doing interesting things," amateur astronomer Ian Musgrave says.
"For example, on August 6 on the western horizon, we're going to see Venus, Mercury, the bright star Regulus, and the crescent moon all together [in the early evening]."
Over the next few months, he also notes there may also be a "new" star to look out for just above the northern horizon.
Astronomers are also on high alert for nova T Coronae Borealis to explode, which would produce a star visible to the naked eye in the region for the first time in 80 years.
What makes this time of year so special for stargazing?
As Earth moves around the Sun throughout the year, our view of our home galaxy, the Milky Way, changes.
Our galaxy is flat, like a pancake, Dr Banks explains.
In summer, we look out towards the edge of this pancake, so we see fewer stars, but in winter we look right into the heart of it.
If our galaxy wasn't flat "we wouldn't have these gorgeous, dusty lanes stretching across the sky", she says.
The other reason winter is particularly good for stargazing is, somewhat paradoxically, the weather.
Australia is a big country, with plenty of variation in weather patterns, but according to Dr Musgrave, the colder the weather, the better the sky viewing.
"A lot of the dust and nastiness … that makes the skies less brilliant during summer has either been washed out or settled, so the skies are clearer," he says.
In colder weather, air holds less water vapour, so winter skies can look less hazy.
"You spend a lot of time looking at clouds, and then when the clouds clear, you get this brilliant, amazing sky," he said.
Stargazing is also particularly good when the Moon is below the horizon all night long during the new moon phase of the monthly lunar cycle.
What are you waiting for?
OK, it's cold, so you'll need to put some layers on for a start.
"If you're not rugged up to the nines, you are going to get very, very shivery, very, very rapidly," Dr Musgrave says.
But once you've braved the cold, there are a few tricks that'll help you get the most spectacular winter views.
If you're based in an urban area, or you live somewhere that experiences light pollution, the first tip is to head somewhere dark.
This can be a dark-sky site, but a location away from lights such as a reserve, camping spot, or even a large park can help.
The ABC Science team is currently asking readers to answer a survey for National Science Week looking at light pollution in your area.
According to Dr Musgrave, who has been an amateur astronomer for decades, you'll need to let your eyes adjust to the darkness.
"All you need is your eyes," he says.
"You don't need fancy equipment."
To understand where certain stars or celestial objects are, he also recommends a sky guide app on your phone. This will allow you to put in your location, and will provide you a digital version of the sky above.
"It's a lot different from my day … where you had to have a paper map, which you held up against the sky to try to work out what's going on.
"There are very few barriers now."
And, if you really can't bring yourself to go out in winter, don't worry. There are other spectacular sights coming up in spring, including a brand new comet.
The comet, called Comet C/2023 A3 (Tsuchinshan-ATLAS) is currently heading towards Earth, and its closest approach will be in late September this year.
It may be as bright as some of the brightest stars in the sky, so is definitely one to keep an eye out for.
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