Hydrogen-Helium Mixtures at Megabar Pressures: Implications for Jupiter and Saturn

Science  15 Nov 1991:
Vol. 254, Issue 5034, pp. 986-989
DOI: 10.1126/science.254.5034.986


Models of Jupiter and Saturn postulate a central rock core surrounded by a fluid mixture of hydrogen and helium. These models suggest that the mixture is undergoing phase separation in Saturn but not Jupiter. State-of-the-art total energy calculations of the enthalpy of mixing for ordered alloys of hydrogen and helium confirm that at least partial phase separation has occurred in Saturn and predict that this process has also begun in Jupiter.