How this cosmic map of magnetic fields could help illuminate one of the universe’s most mysterious forces

The CSIRO used its ASKAP radio telescope to map magnetic fields, illustrated in red (pointing towards Earth) and blue (pointing away). Photograph: CSIRO/Alec Thomson et al./Alex Cherney/Sam Moorfield View image in fullscreen The CSIRO used its ASKAP radio telescope to map magnetic fields, illustrated in red (pointing towards Earth) and blue (pointing away). Photograph: CSIRO/Alec Thomson et al./Alex Cherney/Sam Moorfield How this cosmic map of magnetic fields could help illuminate one of the universe’s most mysterious forces Light from nearly 4m galaxies measured as it twisted and travelled through intergalactic space Follow our Australia news live blog for latest updates Get our breaking news email , free app or daily news podcast A cosmic map of magnetic fields – the largest ever produced – could help scientists delve into one of the major and most mysterious forces in the universe. A global team led by Australia’s national science agency, the CSIRO charted the magnetic fields by measuring light from nearly 4m galaxies as it twisted and travelled through intergalactic space. Sign up for the Breaking News Australia email Dr Alec Thomson, a CSIRO astronomer and astrophysicist said the Earth, stars, galaxies – and the material between galaxies – all had magnetic fields, so the map would enable scientists to investigate fundamental questions about the physics of the universe, and the galaxy we live in. “We still don’t actually know how magnetic fields started in the universe, or how they’ve changed across time since the big bang. And so this type of map helps us start to answer those questions and be able to look at the details of the magnetic universe.” View image in fullscreen CSIRO’s ASKAP radio telescope at Inyarrimanha Ilgari Bundara, at Murchison Radio-astronomy Observatory. Photograph: CSIRO/Alex Cherney The encyclopaedic chart, now published and named “SPICE_RACS” (Spectra and Polarisation In Cutouts of Extragalactic Sources from the Rapid ASKAP Continuum Survey), was made possible by the country’s most powerful radio telescope array, the Australian Square Kilometre Array Pathfinder – located at the Inyarrimanha Ilgari Bundara observatory in Western Australia. The instrument is capable of scanning immense areas of the sky and deep into the far reaches of distant galaxies. Prof Naomi McClure-Griffiths, an author of the paper and chief scientist of the Square Kilometre Array observatory, said previous efforts to map magnetic fields didn’t even cover the southern sky. The largest cosmic map of the universe ever produced “For the past 20 years we have been working with essentially the same dataset,” she said. “Now, we can finally answer some big questions with a much better picture of the universe’s magnetic structures.” The dataset, which was five times larger and much more detailed than previous efforts, has been made available to scientists around the world, and published by the Astronomical Society of Australia. Prof Lisa Harvey-Smith, an a