The Conversation contributed the article to Space.com's expert voices.
Christopher Riseley (opens in new tab), Research Fellow, Università di Bologna
Tessa Vernstrom (opens in new tab), Senior research fellow, The University of Western Australia
There are huge structures at the intersection of the Cosmic Web and the universe. A single cluster can span millions of light years and be made up of hundreds, or even thousands, of galaxies.
Only a small portion of a cluster's total mass is represented by these galaxies. About 80% of it is dark matter and the rest is a hot soup of gas and weak magnetic fields.
We and our international team of colleagues have identified a series of rarely observed radio objects, including a radio relic, a radio halo and fossil radio emission. Existing theories about the origins and characteristics of such objects are out of date.
We can study a wide range of processes in environments we can't recreate in our labs.
A lot of energy is put into the particles of the hot plasma when clusters collide. There are different shapes and sizes of this emission.
One example is radio relics. The arcs sit towards the outskirts of the cluster and are powered by the waves that travel through the plasma. When an aircraft breaks the sound barrier, there is a sonic boom.
There are radio haloes that lie towards the center. The particles get their energy from the turbulence in the hot plasma. Many of the details of haloes and relics are not known.
There are radio sources that arefossil. The radio leftovers come from the death of a black hole.
Black holes shoot huge jets of gas far out into the universe. The jets start to evaporate as they run out of fuel. Radio fossils are what we find when we look at the remnants.
Our new paper was published in the Monthly Notices of the Royal Astronomical Society.
Around 800 million light-years away, this is a chaotic and messy colliding system. All of the hallmarks of a system that should be host to relics and haloes have been found.
We used new data from the ASKAP radio telescope and the Australia Telescope Compact array after conducting work using the Murchison Widefield array.
Data paints a complex picture. The lead image shows features where energy input is active. The hot plasma is captured at X-ray wavelength.
Features that are only visible at lower frequencies are shown in red. These objects are old and have less energy. They have lost a lot of energy over the years.
The radio relic can be seen in red near the bottom of the picture. Our data shows features that have never been seen before.
It is called a "wrong-way relic" due to its unusual shape. Our data breaks our understanding of how relics are created, and we are still trying to understand the physics behind radio objects.
The radio fossil is very faint and red and indicates that it is old. A central black hole that has been switched off is believed to be the source of this radio emission.
Our models can't fit the data Gaps in our understanding of how these sources evolve are revealed by this.
We found the first detection of a radio halo in Abell 3266 by de-focusing the lead image to look for a faint emission that was invisible at high resolution.
This is the beginning of the journey to understand Abell 3266. Our study has raised more questions after uncovering a wealth of new information.
We used telescopes to lay the groundwork for the Square Kilometre Array project. Astronomers can use studies like ours to figure out what they don't know.
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