Saturn’s northern pole is famous for its hexagonal jet stream, a striking atmospheric feature that has been observed for over 44 years. Recently, scientists have discovered a new pattern at Saturn’s southern pole: a decagonal, or 10-sided, atmospheric structure. This decagon, with each vertex about 17,000 kilometers apart, was first spotted in October 2023 by the Hubble telescope as part of the OPAL (Outer Planet Atmospheres Legacy) program, a collaboration between NASA and the European Space Agency (ESA). The program uses the Hubble telescope to study the atmospheres of gas and ice giants like Saturn. Follow-up observations in 2024 and 2025 helped confirm the decagon’s shape and characteristics. The decagon moves slowly from west to east at about 9 km/h, much slower than the hexagon’s speed of 360 km/h. It spans from 53°S to 66°S latitude, covering a width of 13,000 kilometers. It is part of Saturn’s powerful jet stream and forms multiple layers in the atmosphere. Unlike Earth’s violent storms or hurricanes, this decagonal pattern is likely a wave-like movement of air, similar to those seen in Earth’s mid-latitudes, which influence weather systems. Nearby, a smaller decagon has been observed in a less bright area, and it seems to be part of the same dynamic structure. This smaller decagon becomes visible due to clouds at a different latitude. Agustín Sánchez-Lavega, an astrophysicist at the University of the Basque Country in Spain and lead author of the study, explained that the two decagons are linked and represent the same atmospheric phenomenon. Images taken between 2023 and 2025 also show a "red spot" on Saturn’s surface, about 4,000 kilometers long, located at latitude 55°S. Wind measurements suggest it is a massive anticyclone, moving much faster than the decagon at around 83 km/h. This structure is similar to "Anne’s Spot," a feature detected by the Voyager 1 and 2 probes in 1981. Scientists think this high-pressure system could be pushing the jet stream southward, contributing to the formation of the decagon. Amy Simon, a principal scientist leading the OPAL program and co-author of the study, noted that the decagon appears to have formed recently, raising the question of why it wasn’t detected earlier. The researchers suggest using the Hubble and James Webb telescopes for further observations to understand the origin of the decagonal wave. Saturn is the only planet in the Solar System known to have polygonal cloud bands around its poles, making these discoveries especially intriguing for understanding its atmospheric dynamics.