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Now, an international research team including astronomers from WA’s Curtin University are using information gleaned from the signal’s journey through that intergalactic gas to broaden our understanding of the forces shaping those giant pinwheels of stars.

And the study has yielded a few surprises.

Astrophysicist Associate Professor Jean-Pierre Macquart, from Curtin’s node of the International Centre for Radio Astronomy Research, said the team initially thought the FRB signal would be distorted by the gas as it travelled through, similar to air shimmering on a hot summer’s day.

Instead, the research, published today in the journal Science, showed the pulse of energy appeared to travel through a “calm sea of unperturbed gas”.

This paints a picture of a more “serene” environment surrounding galaxies, where gas can extend up to 10 times further than the stars which make them up.

“We think that all galaxies – or at least, a large number of massive galaxies – have these gaseous halos around them, and they extend out into intergalactic space,” Dr Macquart said.

But what is interesting is what happens to these massive galaxies as they grow – or, rather, when they stop.

According to the laws of physics as researchers understand them, when taking into account the abundance of gas and other material, galaxies should keep growing and growing and producing more stars.

Except they don’t, instead going through what Dr Macquart described as a “cosmic downsizing”.

“And one the reasons is, a lot of the fuel they have to continue forming stars, they actually throw out of the galaxy, right out into intergalactic space, and then they stop growing,” he said.

“What we have been able to do with this fast radio burst is actually get a completely new diagnostic on what is happening out in these outer regions of galaxies.”

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A “serene” environment is surprising, Dr Macquart said, because it stands in contrast to the violent process of the creation of stars and ejection of matter at high speeds.

“You would expect there to be at least a measurable magnetic field and a signature of that turbulence, and you’d expect there to be a fair bit of dense gas lingering around,” he said.

“And the surprising thing was that we saw none of that. It was like the sea of tranquillity.”

Why these gaseous halos are so calm of course remains a mystery to be unravelled through further study; the researchers plan to use the FRB method to peer at environments around other galaxies.

University of California Professor of Astronomy and Astrophysics Xavier Prochaska, who led the research, said the results appeared to reveal something new about galactic halos.

“Unless of course, this galaxy happens to be just some weird exception – and with only one subject you can’t be sure about that,” he said.

And the mystery of fast radio bursts has deepened thanks to the power of the ASKAP facility in WA’s Mid West.

The burst detected last year was initially thought of as a huge, “blobby” explosion.

But by going through the data and looking at the event across the most miniscule timescales, Dr Macquart and his colleagues revealed the burst was in fact a series of four “pulses”, which left them pondering what in the universe could create such a signal.

“We detect these pulses with a time resolution of about 800 microseconds,” Dr Macquart said.

“But we can get that data again and look at it in a timescale of about 40 microseconds ... when we did that we saw that what we thought was just one ‘blobby’ pulse actually broke up into these four separate things, it’s just remarkable.

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“If it’s one explosion that blows the system apart, then how does it survive to emit four pulses, but then we don’t see anything ever more?

“Were those four pulses all part of the one explosion? Was it not an explosion at all? It does deepen the mystery.”