In planets' cores, molecules may not compress tightly
When squeezed to pressures and temperatures like those inside giant planets, water molecules are less squeezable than anticipated, defying a set of decades-old equations used to describe watery behavior over a range of conditions.
Studying how molecules behave in such environments will help scientists better understand the formation and composition of ice giants like Uranus and Neptune, as well as those being spotted in swarms by planet hunters. The new work, which appears in the March 2 Physical Review Letters, also suggests that textbooks about planetary interiors and magnetic fields may need reworking.
“At this point, it’s worth putting together an accurate equation of state over the entire pressure range for planetary modelers to use,” says Bill Nellis, a physicist at Harvard University. Nellis notes that while the new study has generated reliable data for the conditions in question, more work is needed to determine how the new numbers