Inside the cores of ice giant planets, the pressure and temperature are so extreme that the water residing there transitions into a phase completely unfamiliar under natural conditions on Earth.

Known as ‘superionic water’, this form of water is a type of ice. However, unlike regular ice, it’s actually hot, and also black.

For decades, scientists thought that the superionic water in the core of Neptune and Uranus was responsible for the wild, unaligned magnetic fields that the Voyager 2 spacecraft saw when passing them.