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ESA’s Solar Orbiter has given scientists their first clear view of the Sun’s poles, a region that has long remained hidden from observation. The findings reveal unexpected plasma flows and magnetic field movements that may reshape current understanding of how the Sun’s magnetic cycle operates. For decades, the Sun’s poles have been among the least understood parts of our star. From Earth, scientists can only glimpse these regions at a sharp angle, making it nearly impossible to study their magnetic properties. Most space probes orbit the Sun along the same plane as the planets, offering little improvement. “To understand the Sun’s magnetic cycle, we still lack knowledge of what happens at the Sun’s poles. Solar Orbiter can now provide this missing piece of the puzzle,” said Sami Solanki, MPS Director and co-author of the new study. Launched in February 2020, the European Space Agency’s Solar Orbiter has been following a looping path around the Sun. In March this year, it shifted its orbit to tilt about 17 degrees above the plane of the planets, giving scientists a much better vantage point of the polar regions for the first time. Mapping the magnetic network Researchers at the Max Planck Institute for Solar System Research (MPS) used data from two of the spacecraft’s instruments: the Polarimetric and Helioseismic Imager (PHI) and the Extreme-Ultraviolet Imager (EUI). The PHI data were collected on March 21, while the EUI recorded observations between March 16 and 24. Together, they provided new insights into plasma flows and magnetic structures at the Sun’s south pole. The team identified a detailed pattern of supergranulation and the surrounding magnetic network. Supergranules are vast cells of hot plasma, each two to three times the size of Earth, that cover the solar surface. Their horizontal flows push magnetic field lines toward the edges of the cells, creating a web of strong magnetic regions. To their surprise, the researchers found the magnetic field drifting toward the pole at speeds of 10 to 20 meters per second. That rate is almost as fast as the flows seen closer to the equator. Earlier observations made from the ecliptic plane had indicated that magnetic motion slowed dramatically near the poles. Tracking the Sun’s magnetic engine “The supergranules at the poles act as a kind of tracer. They make the polar component of the Sun’s global, eleven-year circulation visible for the first time,” said Lakshmi Pradeep Chitta, research group leader at MPS and first author of the study. These new observations provide key evidence of how the Sun’s magnetic fields travel across its surface and feed into deeper layers, powering the familiar eleven-year solar cycle. However, scientists are still unsure whether the global “magnetic conveyor belt” truly maintains its speed near the poles or eventually slows down. The study offers only a brief snapshot of one stage in the solar cycle. Researchers say more long-term data will be needed to confirm how consistent these polar flows are. With Solar Orbiter continuing its tilted trajectory, future observations are expected to reveal even more about the hidden processes that govern the Sun’s magnetic rhythm.
