While Uranus and Neptune are referred to as “ice giants,” their temperatures and pressures are so high that extraordinary physical reactions occur.
Indeed, scientists believe that diamonds are capable of forming and raining on these worlds.
Nature Communication has published experimental proof that this strange occurrence may occur. Researchers used the astounding SLAC (the US DoE’s National Accelerator Laboratory) Linac Coherent Light Source (LCLS) to investigate how a hydrocarbon would act under the pressure and temperatures predicted 10,000 kilometers (6,200 miles) inside Neptune.
At a pressure of about 1.5 million atmospheres and a temperature of 4,730 °C (8,540 °F), the hydrocarbon separates into its basic elements of carbon and hydrogen. At least a fifth of the carbon clumps together, according to laboratory testing. And it is in these clusters that carbon takes on its most stable configuration: diamonds.
“This research provides data on a phenomenon that is very difficult to model computationally: the ‘miscibility’ of two elements, or how they combine when mixed,” LCLS Director Mike Dunne explained in a statement. “Here they see how two elements separate, like getting mayonnaise to separate back into oil and vinegar.”
“In the case of the ice giants we now know that the carbon almost exclusively forms diamonds when it separates and does not take on a fluid transitional form,” lead author Dr. Dominik Kraus, from Helmholtz-Zentrum Dresden-Rossendorf, said.
Diamond rain on Neptune and Uranus is critical to these faraway worlds’ internal energy balance. Diamonds created in the laboratory would sink, creating heat as they rubbed against the thick substance around them. This would enable the planets to maintain such a high internal temperature.
While this discovery will undoubtedly aid in our understanding of these planets and comparable places outside the Solar System, the approach used in the study, devised by Kraus, has the potential to go far further.
It may be used to investigate the behavior of such extremes on pure hydrogen, simulating conditions observed in tiny stars or nuclear fusion reactors. Investigating these features may be critical for mastering some fusion procedures for which we now lack a thorough grasp.