Swiss researchers challenge assumptions about Neptune and Uranus

The planets Uranus and Neptune could be hiding significantly more rock in their interiors than previously assumed. This new discovery by a Zurich research team calls decades of theories into question.

+Get the most important news from Switzerland in your inbox

The two “ice giants” of our solar system could turn out to be “rock giants”, as the University of Zurich (UZH) announced on Wednesday.

The eight planets in our solar system are generally divided into three categories based on their composition: close to the sun are the four “rocky planets” Mercury, Venus, Earth and Mars, followed by the two “gas giants” Jupiter and Saturn and finally the two “ice giants” Uranus and Neptune.

However, the new study turns this classic categorisation on its head. This discovery is based on a newly developed model created by researchers at the University of Zurich to analyse the inner structures of the two planets in more detail.

Thanks to the new model, the UZH team discovered that the possible composition inside the “ice giants” of our solar system is by no means limited to ice. “We first suspected this almost 15 years ago, and now we finally have computational proof,” said UZH professor Ravit Helled, according to the press release.

Gas giants or ice giants?

Despite these promising results, a certain amount of uncertainty remains, according to the researchers. Physicists still have little understanding of how materials behave under the pressure and temperature conditions inside a planet. This could influence the results.

“Both Uranus and Neptune could be rocky giants or ice giants, depending on the modelling assumptions. However, the current data is not sufficient to distinguish between the two variants. This would probably require targeted missions to Uranus and Neptune,” says Helled.

Translated from German by DeepL/mga