ESA's Solar Orbiter Reveals First Close-Up of the Sun's Polar Magnetic Engine in Motion

ESA's Solar Orbiter captures the Sun's magnetic machinery at the south pole

In a dramatic new observation, the European Space Agency's Solar Orbiter has provided the first close-range view of the Sun's magnetic field near its south pole, revealing unexpectedly rapid poleward motion of magnetic structures.

The composite image — assembled from eight days of observations in March 2025 when the spacecraft first obtained a clear view of the region after tilting its orbit by 17° — shows bright, sweeping arcs around the pole. These luminous arcs trace magnetic structures drifting toward the solar limb at speeds higher than prevailing models predicted.

How the observation was made

Researchers analyzed data from two of Solar Orbiter's primary instruments: the Polarimetric and Helioseismic Imager (PHI) and the Extreme Ultraviolet Imager (EUI). Working together, PHI and EUI map magnetic fields and hot plasma across the solar surface, focusing on the chromosphere where the magnetic network leaves visible imprints.

In the chromospheric images, bright, elongated arcs trace the motion of magnetic features as the Sun rotates. These arcs reveal that supergranules — vast convective cells roughly two to three times the diameter of Earth — are transporting magnetic fields toward the poles at roughly 20–45 miles per hour (32–72 km/h).

"The polar supergranules act as tracers that make the polar part of the Sun's eleven-year circulation visible for the first time," said Lakshmi Pradeep Chitta of the Max Planck Institute for Solar System Research, lead author of the study.

Those polar flows are nearly as fast as comparable surface flows nearer the equator and considerably faster than theoretical expectations. The unexpectedly high poleward speeds indicate the Sun's magnetic field is migrating toward the poles more rapidly than many models had predicted.

Why this matters

The Sun operates on an approximately 11-year magnetic cycle in which field lines twist, flip and rebuild, producing sunspots, flares and occasional powerful storms that can affect Earth. At the heart of this cycle is a slow global circulation — a "magnetic conveyor belt" of plasma currents that transports magnetic field lines toward the poles near the surface and back to the equator deep inside the Sun. The polar regions are a crucial, previously hidden part of this circulation; direct observations like these provide missing constraints for solar dynamo models.

This work, published Nov. 5 in The Astrophysical Journal Letters, opens a new era in polar solar exploration and offers long-awaited data to improve our understanding of the engine that drives the solar cycle and the magnetic environment shaping the solar system.

Image and data: European Space Agency / Solar Orbiter (PHI & EUI). Study published Nov. 5 in The Astrophysical Journal Letters.