Australian scientists map the universe’s magnetic fields
Scientists have published the largest and most detailed map ever made of the universe’s magnetic fields, using data from Australia’s most powerful radio telescope to visualize the hidden force that could help govern the structure of the entire universe.
The project sheds crucial light on the last bastion of cosmic mystery: how these massive magnetic structures influence the formation of galaxies, the birth of stars, the roar of radioactive “space weather” and the longevity of our galaxy.
CSIRO scientist Dr. working at the SKA Observatory in Western Australia. Alec Thomson said the map is five times larger than all previous efforts to visualize the magnetism of the universe.
“This gives us the best view we have yet of magnetic fields in the universe,” Thomson said.
“We can see further than we could before, and we can see the Milky Way in 10 times better detail.”
Intergalactic magnetism may be as important as gravity to the architecture of space; It can affect the flow of matter through space and shape the evolution of the universe as we know it.
Magnetic fields are created when electric charges move (such as electrons flowing through a wire).
For example, electrically conductive molten metal in the Earth’s core produces a broad magnetic field that protects the planet from space radiation and solar flares.
Without it, our atmosphere would be destroyed by the cosmic wind and our planet would be as barren as Mars.
Over the past few decades, we have begun to understand that magnetic fields are also produced by the rotation of galaxies and supernova explosions.
This contributes to a complex network of magnetism that extends throughout the universe.
Approximately 99.9 percent of the visible material in the universe by volume is plasma, or charged gas, which can be manipulated and manipulated by magnetism.
“This is why magnetic fields have such a strong influence on how this material moves through the universe and inside galaxies,” Thomson said.
Large-scale simulations of the universe show that galaxies are not flung randomly through space but gather in clusters connected by filaments, resulting in images that resemble neurons in the brain or red-backed spider webs.
Gravity plays an important role in this structure, but magnetism may be another important architect.
Magnetic fields also act as a barrier to gravity that clumps together gas and dust, slowing the formation of new stars by a factor of three. The fields also support how electromagnetic interstellar winds blast from stars into space.
Thomson and his co-authors have made the map data public so that others can use it to learn more about these phenomena.
The new maps were made using data from CSIRO’s ASKAP radio telescope, 750 kilometers north-east of Perth.
Light speeding towards Earth from distant galaxies is bent as it passes through magnetic fields.
Scientists processed the data captured by the telescope to understand exactly how light waves bend on their way to Earth. By working backwards, the researchers were able to locate and map magnetic fields.
Scientific images produced by the project team show magnetic fields as they appear from Earth.
“Red is where magnetic fields are pointed toward us, and blue is where magnetic fields are pointed away from us,” Thomson said.
The maps also show magnetic fields ejected by nearby galaxies called the Magellanic Clouds. Professor Naomi McClure-Griffiths, principal scientist at the SKA Observatory and co-author of the new study, studies how magnetism affects the interaction of these neighboring galaxies with the Milky Way.
The astrophysicist is also keen to investigate how magnetic fields affect “galactic cannibalism”, the process by which galaxies extract gas from smaller galaxies and use it as raw material to form new stars.
The Milky Way’s magnetic fields and the galaxy it wants to “eat” can repel each other, slowing down this feeding process that helps keep the galaxy going.
“If this process is slowed down by magnetic fields, then it would also have implications for the lifetime of our own galaxy,” McClure-Griffiths said.
Researchers hope the mapping data will accelerate fundamental discoveries about the formation and architecture of the universe and how space becomes a magnetic field.
The first data are called Rapid ASKAP Continuity Surveys (RACS). Add in the new part of the project – Spectrum and Polarization in Intersections of Extragalactic Sources – and you get SPICE-RACS, a name that evokes an ordinary object but represents some of the most enormous and mysterious structures in existence.
Thomson said the maps were “just the beginning” and that major breakthroughs would occur in the coming years.
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Angus Dalton is science correspondent for The Sydney Morning Herald.Connect with: X or email.
