Saturn and its rings, captured by the Cassini spacecraft NASA/JPL-Caltech/Space Science Institute Specks of dust from Saturn’s rings appear to float much farther above and below the planet than scientists thought possible, suggesting the rings are more like a giant dusty doughnut. The main structure of Saturn’s rings is extremely thin, extending outwards for tens of thousands of kilometres but only vertically for around 10 metres, which creates the planet’s striking appearance when viewed from Earth. There is some variation in this shape, however, such as the puffier outer E ring fed by Saturn’s moon Enceladus, which spurts out ice from its underwater ocean. Now, Frank Postberg at the Free University of Berlin and his colleagues have analysed data NASA’s Cassini spacecraft during 20 orbits in 2017, the mission’s final year, when it took extremely steep paths through the rings, starting from distances up to three times Saturn’s radius above the planet and sweeping to the same distances below. Cassini’s spectrometer, the Cosmic Dust Analyzer, found hundreds of tiny rocky particles near the top of …