NASA's Hubble Telescope Detects Ten-Sided Atmospheric Wave at Saturn's South Pole
Researchers have identified a decagonal structure in Saturn's southern hemisphere, the first regular-sided jet pattern of its kind ever observed there.
What happened
NASA's Hubble Space Telescope, combined with ground-based observatory imagery, has detected a ten-sided atmospheric wave at Saturn's south pole. As Saturn's seasons changed, its south pole came into alignment with ground-based observatories. In images from those telescopes submitted to the Planetary Virtual Observatory Laboratory, amateur astronomers Trevor Barry and Jean-Paul Oger, along with Agustín Sánchez-Lavega of the University of the Basque Country in Spain, noticed an undulating band along Saturn's south pole. In further 2025 ground-based telescope images, this began to suggest a decagonal (ten-sided) structure. With Hubble's incredible image clarity and spatial resolution, the team resolved the decagonal shape with certainty. Hubble data confirmed the feature's presence back to 2023. The wave is a three-dimensional structure extending through multiple atmospheric layers within one of Saturn's jet streams. The findings appear in a September 2, 2026 paper published in Science Advances.
Context
Saturn's north pole has hosted a hexagonal atmospheric wave for more than 40 years, making the sudden appearance of a decagonal counterpart at the south pole scientifically significant. The south pole structure appears to be strengthening, offering researchers a rare opportunity to observe a giant atmospheric pattern developing in real time. The discovery raises fundamental questions about atmospheric dynamics on gas giants: how the decagon formed, why it emerged now when no similar long-lived formation was detected in Cassini spacecraft imagery from 2004-2017, how long it will persist, and how it compares to the northern hexagon. Further observation and computer modeling are required to understand the phenomenon and potentially inform understanding of atmospheric processes on Earth.