Welcome to the Quanta Science podcast. Each episode, we bring you stories about developments in science and mathematics.

I'm Susan Vallett. A new technique has produced detailed maps of the magnetic fields in colossal galaxy clusters.

If confirmed, the approach could be used to reveal

where cosmic magnetic fields come from. That's next.

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By making maps of the magnetic fields hidden inside massive galaxy clusters,

astronomers are getting closer to finding the origin of cosmic magnetism.

Alexander Lazarian is an astronomer at the University of Wisconsin-Madison.

He's a co-author on the paper describing the maps published in Nature Communications.

This is the first maps of the detailed structure of the magnetic fields on the

precedently large scale. Lazzarian and his colleagues studied five galaxy clusters, each spanning millions of light

years.

They made the maps using a technique he devised called synchrotron intensity gradient or

sig mapping.

It relies on radio observations to work out which way a cluster's magnetic field points at a given location.

By applying the same technique across an entire cluster, the researchers say they can

construct a complete map of its magnetic fields. If confirmed, the results would show that

there's a previously undetected order to magnetic fields in giant structures.

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