For the first time, scientists have used satellite data to create a 3D map of the sun’s interior magnetic field, the fundamental driver of solar activity. The research, published in The Astrophysical Journal Letters, should enable more accurate predictions of solar cycles and space weather that affects satellites and power grids.

The sun is more than just a fiery hot ball of hydrogen and helium gas. It is a giant magnetic star. Beneath the surface is a magnetic layer that is responsible for everything from the dark spots we see on its face to violent flares that erupt into space. Because of the disruption caused by solar storms, we need to know what is going on inside. We can’t directly observe the interior, so to date we have relied on models that depend on simplified assumptions. But these can be inaccurate.

To get a better idea of what is going on inside the sun, researchers from India fed 30 years of daily magnetic maps from satellites (from 1996 to 2025) into a sophisticated 3D model of the solar dynamo, the physical process that generates the sun’s magnetic field. By using this real-world data, they could track how magnetic fields move deep beneath the surface, where satellites cannot penetrate.