Scientists discover superionic water—a bizarre state hidden in ice giants

Scientists have uncovered a new form of water called superionic water. This unusual state forms under extreme heat and pressure, with hydrogen ions flowing freely through a fixed lattice of oxygen atoms. The discovery could reshape our understanding of distant planets like Uranus and Neptune.

An international research team made the breakthrough using two of the world's most advanced X-ray lasers: the European XFEL and the LCLS. These facilities allowed them to capture the atomic structure of superionic water with ultra-precise, ultrashort X-ray pulses.

The experiments revealed that superionic water has a hybrid, disordered oxygen structure. It combines elements of face-centred cubic and densely packed hexagonal arrangements. Under extreme conditions, hydrogen ions move like a liquid while oxygen atoms remain locked in a solid framework.

This newly identified phase may exist deep inside ice giants such as Uranus and Neptune. If so, it could explain their puzzling magnetic fields. Recent findings suggest that superionic water alters thermal conductivity and electrical properties in planetary interiors. These changes might influence how magnetic fields are generated, though further research is needed to confirm the full impact on planetary models.

The discovery of superionic water provides new insights into the behaviour of matter under extreme conditions. Its potential presence in ice giants could refine models of their internal structures and magnetic fields. Scientists continue to study how these findings will integrate into broader planetary research.