Scientists have developed an unusual form of ice that remains solid despite temperatures exceeding those of lava. This material could potentially help explain the strange magnetic fields of the planets Uranus and Neptune.
This substance has been named superionic ice. It differs fundamentally from ordinary freezer ice. Under extreme pressure and high temperature, water can transition into a peculiar state where oxygen atoms form a solid framework, while hydrogen nuclei move through it like a liquid. This structure gives the ice electrical conductivity.
Researchers from France presented new details about the arrangement of atoms in this material according to a recent report published in Science and Technology Daily. To study the sample, the team compressed a tiny sample of water more than two million times the Earth's atmospheric pressure and heated it to over 1500 degrees Celsius. Under normal conditions, water should turn into superheated gas at these parameters, but the immense pressure keeps it in a solid state.
The scientists discovered that the oxygen atoms formed a previously unknown crystal structure, which is a discovery contributing to the understanding of this exotic ice's behavior. This is significant because Uranus and Neptune are known for their anomalous magnetic fields. Unlike Earth, whose magnetic field is roughly centered and aligned with the axis of rotation, the magnetic fields of these gas giants are highly tilted and offset.
For a long time, scientists have hypothesized that a layer of electrically conductive superionic ice inside these planets might be the cause of the observed phenomena. If this hypothesis is correct, the strange magnetic fields recorded in the 1980s by the Voyager 2 spacecraft, managed by the National Aeronautics and Space Administration (NASA), will make much more sense. Although superionic ice was predicted decades ago, its experimental confirmation only occurred in 2018. The new work adds another piece to this puzzle, demonstrating that water, so ordinary on Earth, can acquire almost alien properties under certain conditions. This could also help science better understand the internal structure of some of the most mysterious worlds in the Solar System.