06/12/2026
🧲 Astronomers have released the most detailed map yet of the Universe’s hidden magnetic fields.
The map is called SPICE-RACS, and it was built using CSIRO’s ASKAP radio telescope in Western Australia. Instead of photographing magnetic fields directly, ASKAP measured how radio light from distant galaxies twists as it travels through magnetized space.
That twisting is called Faraday rotation. It tells astronomers where magnetic fields lie along the line of sight, and gives clues to their strength.
The scale is enormous. The team reprocessed data from nearly 4 million radio sources and extracted spectra from about 5 million radio components across roughly 87.5 percent of the sky.
After filtering the data, SPICE-RACS produced the largest single catalog of Faraday rotation measurements ever made, with about 250,000 high-confidence measurements. That is about five times more than all previous rotation measure catalogs combined.
This matters because magnetism is one of the Universe’s great hidden forces. It shapes gas between stars, influences how galaxies grow, and may help reveal how cosmic magnetic fields first appeared after the Big Bang.
The Universe has always been magnetic. Now we are finally beginning to map it.
đź“„ RESEARCH PAPER
📌 Thomson et al., “The Rapid ASKAP Continuum Survey VII: Spectra and Polarisation In Cutouts of Extragalactic Sources (SPICE-RACS) Second Data Release: Unveiling the Magnetised Sky”, Publications of the Astronomical Society of Australia (2026)
