Diamond rain? Super-ionic water? These are just two proposals that planetary scientists have come up with for what lies beneath the thick, bluish, hydrogen-and-helium atmospheres of Uranus and Neptune, our solar system’s unique, but superficially bland, ice giants.

A planetary scientist at the University of California, Berkeley, now proposes an alternative theory—that the interiors of both these planets are layered, and that the two layers, like oil and water, don’t mix. That configuration neatly explains the planets’ unusual magnetic fields and implies that earlier theories of the interiors are unlikely to be true.

In a paper appearing in the journal Proceedings of the National Academy of Sciences, Burkhard Militzer argues that a deep ocean of water lies just below the cloud layers and, below that, a highly compressed fluid of carbon, nitrogen and hydrogen.

Using the set of first-light observations from the new William Herschel Telescope Enhanced Area Velocity Explorer (WEAVE) wide-field spectrograph, a team of more than 50 astronomers, led by Dr. Marina Arnaudova at the University of Hertfordshire, has presented the first WEAVE scientific results on Stephan’s Quintet in the Monthly Notices of the Royal Astronomical Society.

This state-of-the-art wide-field spectrograph is a 20-million Euro project that brings together leading experts from around the world. WEAVE is set to revolutionize our understanding of the universe, offering unprecedented detail, as demonstrated in this new study of Stephan’s Quintet.

Stephan’s Quintet, also known as the Hickson Compact Group 92, is a nearby galaxy group that consists of five galaxies (NGC 7,317, NGC 7318a, NGC 7318b, NGC 7,319 and NGC 7320c). Ever since its discovery in 1877, it has captivated astronomers, particularly because it represents a galactic crossroad where past collisions between galaxies have left behind a complex field of debris.

The planet, a very young gas giant, is about 521 light-years away from Earth. Its strange orbit also enables researchers to get exciting information as it transits in front of its parent star with little to no obstructions to Earth-based instruments, like NASA’s Transiting Exoplanet Survey Satellite (TESS), which made the discovery.

IRAS 04125+2902 b is roughly the same age as its parent star, which is far too brief in cosmic terms under our current understanding of planet formation.

IRAS 04125+2902 b has a radius roughly 10.7 times larger than that of Earth, making it comparable in size to Jupiter. However, it is significantly less dense, possessing only 30% of Jupiter’s mass.