Overview
- Researchers led by Yamila Miguel at the Netherlands Institute for Space Research modeled the interiors of Uranus and Neptune and found their outer shells could be mostly rock with hydrogen and helium.
- The simulations tested how materials behave under extreme pressure and heat and indicate that silicate minerals may condense deep inside the planets.
- The hypothesis draws on evidence that Kuiper Belt objects such as comets and Pluto contain substantial rocky material, suggesting similar building blocks for the two worlds.
- The authors say the findings warrant rethinking the long-used term “ice giant,” with one proposal to adopt a neutral label like “minor giants.”
- The study remains preliminary and model-based, makes no claim that the atmospheres are rocky, and has not prompted any official reclassification.