Square Kilometre Array: The Australian telescope built to see the dawn of the universe
Posted
In a West Australian landscape billions of years old sits the Australian Square Kilometre Array Pathfinder, a cutting edge astronomical facility designed to listen to the dawn of time.
Four workers pile into a small charter plane, the morning's papers in hand, ready to fly to their remote work site.
But these are not miners: they are the engineers that will enable the world's astronomers to see the birth of the universe.
The plane takes off from the Geraldton aerodrome, gaining height over wheat fields, then pastoral land, then red earth.
Water holes in a creek shine steel grey in the sunlight, but there's no sign of humanity for more than an hour.
The plane lands at a desert airstrip, greeted in silence by a hot wind, a kestrel and a roosting pair of kites.
With modern transport it's a short hop, but it's also a journey to a place that lives as much for the past and the future as it does for the present.
An ancient landscape
In the very beginning, the Earth was a ferocious place. Vast asteroid storms pummelled the surface and enormous spurts of red hot magma flowed across its shell, destroying the planet's early crust.
Despite the trauma, tiny fragments of the earliest proto-crust, zircon fragments 4.4 billion years old, can be found in a small area in the Jack Hills of Western Australia, 400 kilometres north-east of Geraldton.
The fragments are found in an area called the Yilgarn Craton, an ancient and stable geological zone, and the home of the Australian Square Kilometre Array Pathfinder (ASKAP).
"The Earth is only 4.7 billion years old," says Antony Schinckel, ASKAP project director.
"So in this area of the world is some of the oldest rock ever discovered. You really get a sense of that, I think, when you're in the landscape out here."
The array
The array, built to receive radio waves from the universe's very beginnings, is a good place to ponder mind-bending timescales.
It takes time for radio waves to travel from the stars all the way to Earth — hundreds, thousands, millions or even billions of years.
The antennas that form the array are tall, white dishes, standing in the landscape like inverted mushrooms. The facility comprises 36, arranged across a 4 square kilometre patch of the Earth, like a constellation version of the Vitruvian Man.
Each antenna features the best radio camera the world has ever seen, designed by the CSIRO, called a phased array feed.
It's expected that the ASKAP telescopes will be able to detect radio waves sent out in the first half a billion years of the universe's existence.
ASKAP will be used for many projects including EMU — the evolutionary map of the universe.
Images of about 70 million galaxies new to science will be used, each at various stages in their own evolution.
When lined up, the images will plot a timeline of galaxy formation, right through to when planets are formed, perhaps even planets that could support life.
One of the early pictures taken as a test had more than 2,000 galaxies in it, an exciting sample of what is to come.
The quiet zone
ASKAP sits in a quiet place, where the silence is protected by law.
The array is in the middle of the Australian Radio Quiet Zone, some 260km2 where the use of electronics, which occlude radio telescopes in the same way light does their optical cousins, is strictly controlled.
"Everything that mankind does these days — our phones, our refrigerators, our cars — it generates radio frequency noise and it's often doing that in the same frequency bands that we want to be looking at the universe in," says Mr Schinckel.
"So we have to get away from people, we have to get away as far as we can from anything that's man-made, from any man-made activities.
"We know the energy that's being expended in stars and the movement of objects is incredible — our Sun is a star like many other stars in the universe and there's billions of them in every galaxy."
Yet because of the distances, the energy that we receive from these objects, in any of the bands in optical or in radio, is tiny.
"The numbers we deal with are so extreme. On the one hand everything in the universe is so big, and yet it's also so far away that it looks tiny," Mr Schinckel says.
Big numbers, big data
It looks like a very plain shed in an industrial suburb. There are no windows, and the doors are double layered, like you might imagine on a spaceship.
Inside is a very normal office environment. Desks spill over with half-eaten biscuits and cups of tea and there is a workshop where equipment can be repaired.
"We'll have the equivalent of the entire internet's worth of data going in there every second," says Mr Schinckel.
"So think of all your worst movies — everything that's flying through the internet every second — the equivalent of that but in better taste is going into that building every second."
Inside a bunker within the very core of the building is a supercomputer receiving nearly 5.2 terabytes of data a second (and not all the antennas are online yet).
"What's happened with radio astronomy recently is that the things that we used to think of as cutting edge and the expensive difficult parts — the antenna — they're not," says Mr Schinckel.
"The really cutting edge part these days is all in the signal processes, it's all in the computing system.
"Only a tiny percentage of the budget for this telescope has gone into the telescopes!
"Most of the budget goes into the phased array feeds, these very exciting radio cameras we've developed, and then into the huge supercomputing back end, which is a largely custom system that CSIRO has had to build itself.
"So it's just this bizarre juxtaposition between the classic Australian outback and literally something that's at the cutting edge of the data processing world."
Forty thousand years
Leonie Boddington is a Wajarri woman and a CSIRO Aboriginal liaison officer.
Indigenous people have called the Murchison area home for at least 40,000 years.
"Everything has a name," says Ms Boddington. "The trees have a Wajarri name, the rocks, the hills, so everything comes to life for us as you come and drive back onto country."
The antenna have also been given Wajarri names, such as Jirdilungu (the Milky Way). One is named after Ms Boddington's own father, Ross, one of the last-known song men of the Wajarri people.
"I'm not sure about anybody else, but I'm quite excited and proud that we've got the leading scientific organisation in the world, the CSIRO, on our country," Ms Boddington says.
"I don't think I'm against, most Aboriginal are not against, the building out on country. We just want you to respect us, respect our land.
"My ancestors have been here 40-odd thousand years. While they were building empires and state buildings, our Aboriginal ancestors were building a survival system."
ABC and iview April 4-6
Professor Brian Cox and Julia Zemiro will be joined by scientists and personalities to inspire Australia to explore our solar system. Live from Siding Spring Observatory they will tackle astronomy's most intriguing questions.
In her work liaising between locals and CSIRO, Ms Boddington has learned a lot from both sides. She says one day an elder told her something that surprised her.
"Out on that site out there we actually had a Yamatji god — and his name was Bidgel. I asked where [the god] was from and he goes, 'Out there where the antennas are'.
"I thought, 'Wow, how cool is that?' He's up there looking down on us. I'm a bit excited, I don't know about anyone else."
The creation of ASKAP has been a study in contrasts: ancient stories from distant galaxies, prehistoric rocks and the oldest continuous culture on Earth.
It is futuristic technology built to look into the past. It is one of Australia's most advanced scientific facilities. And it is Wajarri country.
Credits
- Reporter: Ann Jones
- Video: Chris Lewis
Topics: astronomy-space, science-and-technology, computers-and-technology, information-and-communication, indigenous-aboriginal-and-torres-strait-islander, geraldton-6530
