Iridescent red and blue ribbons of light arching over the Australian outback are helping scientists understand how the Milky Way galaxy came to be.
Using an advanced radio telescope in remote Western Australia, more than 700km north of Perth, astronomers have been able to visualise the galaxy’s magnetic fields.
It is the most detailed map of the fields yet, providing more clues about the invisible forces that influence the formation of galaxies.
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Astronomers from the CSIRO and SKA Observatory in the Murchison region looked for the way bright radio waves from distant galaxies changed as they came through the Milky Way’s magnetic fields.
The changes are telltale signs of the magnetic fields’ strength and direction.
“What we’re doing here is looking for those compact, distant, far away galaxies and building up an atlas of those telltale signs,” CSIRO research scientist Dr Tim Galvin said.
Red shows the fields pointing at us
In stunning visualisations of the magnetic fields, the colours also act as directional guides.
The red markings represent the parts of the magnetic field pointing towards Earth, while blue shows the magnetic fields pointing away from us.
More than 1500 observations were made in more than 1400 unique fields, according to a paper published in the journal Publications Of The Astronomical Society Of Australia.
The telescope used to gather the information that helped researchers create the visual map can generate data at the rate of 100 trillion bits per second, or more data at a faster rate than Australia’s entire internet traffic.
To the naked eye, magnetic fields are invisible.
Astronomers looking for them must use the light of distant stars and watch for where it interacts with the magnetic fields.
They can catch the twisting direction of the light — which is itself an electromagnetic wave — in a phenomenon known as polarisation.
A similar map was compiled by researchers in the northern hemisphere 17 years ago, but it could not capture all of the Milky Way because the best view is from the southern hemisphere.
Combining data from the older map and the new, more detailed version would be highly valuable, Galvin said.
“Magnetic fields are a pretty fundamental force and galaxy formation is a pretty big deal because the universe has evolved in a very particular way to get us to where we are now,” he said.
“Understanding how these magnetic fields affect galaxy formation is a pretty important question.”
‘When did magnetic fields first appear?’
Magnetic fields can impact how galaxies evolve.
They can store energy and impact the speed at which new stars are formed.
With the discovery of this new dataset comes the possibility of answering some of the universe’s bigger questions.
“We can even potentially find the answer to questions like ‘When did magnetic fields first appear in the universe?’,” lead scientist professor Naomi McClure-Griffiths said.
“We had once thought it would be impossible to answer these questions. I’m excited to say that is no longer the case.”
Research scientist Dr Stefan Duchesne said the data was public and available for anyone to use.
“There’s a lot of archival data available now for people to go away and do their own science,” Duchesne told AAP.
“Science is innovation … so it’s great that we preserve it and make it available.”
