Document Type
Article
Publication Date
3-8-2021
Publication Title
Monthly Notices of the Royal Astronomical Society
Volume
503
Issue
2
First page number:
2825
Last page number:
2832
Abstract
Water (H2O), in all forms, is an important constituent in planetary bodies, controlling habitability and influencing geological activity. Under conditions found in the interior of many planets, as the pressure increases, the H-bonds in water gradually weaken and are replaced by ionic bonds. Recent experimental measurements of the water equation of state (EOS) showed both a new phase of H-bonded water ice, ice-VIIt, and a relatively low transition pressure just above 30 GPa to ionic bonded ice-X, which has a bulk modulus 2.5 times larger. The higher bulk modulus of ice-X produces larger planets for a given mass, thereby either reducing the atmospheric contribution to the volume of many exoplanets or limiting their water content. We investigate the impact of the new EOS measurements on the planetary mass–radius relation and interior structure for water-rich planets. We find that the change in the planet mass–radius relation caused by the systematic differences between previous and new experimental EOS measurements is comparable to the observational uncertainties in some planet sizes – an issue that will become more important as observations continue to improve.
Keywords
Methods: Numerical; Planets and satellites: Interiors; Composition
Disciplines
Cosmochemistry | The Sun and the Solar System
File Format
File Size
1274 KB
Language
English
Rights
IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/
Repository Citation
Huang, C.,
Rice, D. R.,
Grande, Z. M.,
Smith, D.,
Boisvert, J. H.,
Tschauner, O.,
Salamat, A.,
Steffen, J.
(2021).
Implications of an Improved Water Equation of State for Water-Rich Planets.
Monthly Notices of the Royal Astronomical Society, 503(2),
2825-2832.
http://dx.doi.org/10.1093/mnras/stab645