3 min readMay 14, 2026 02:10 PM IST For decades, scientists have classified Uranus and Neptune as “ice giants” – massive outer planets believed to contain large amounts of icy material beneath their atmospheres. But new research is challenging that long-held understanding, suggesting the two planets may contain far more rock-rich material in their interiors than previously thought. Researchers say the findings could reshape how scientists understand the composition of the two distant planets. “We found out that both Uranus and Neptune have their outer shells made mostly of rocks (and hydrogen and helium gas). This goes against the common belief that they are ice-giant planets,” author Yamila Miguel of the Netherlands Institute for Space Research told Space.com. The new modelling study suggests Uranus and Neptune may contain more rock-rich material internally than scientists previously believed, challenging the traditional idea that the planets are dominated by ice. However, researchers have not concluded that the planets’ atmospheres are rocky, nor have Uranus and Neptune been officially reclassified. The team used computer models to study the internal …