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Experimentalists can now generate terapascal pressures in the laboratory, conditions sufficient to alter the structure of atoms and the nature of interatomic bonding ( 1 ). These are the pressures of planets' interiors and origins—7 TPa at Jupiter's center, 4 TPa in the middle of Saturn, 0.36 TPa for Earth's inner core—and planet growth involves impacts that generate pressures into the terapascal range ( 2 ). Understanding materials and their properties at such conditions provides key insights into how planetary bodies form and then evolve over billions of years. On page 1063 of this issue, Fratanduono et al. ( 3 ) establish a new calibration for such experiments, and their pressure-volume relations for gold (Au) and platinum (Pt) can now serve as reliable standards to >1 TPa.
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Exoplanets and High Energy Density Plasma Science
Exoplanet science has moved rapidly beyond its initial observational discovery phase with an emerging enterprise of understanding planet formation, evolution, structure and habitability. Understanding conditions in planetary interiors is essential to all of these issues. The evolving state of a planet’s deep interior will determine not only bulk physical characteristics like density and radius but also whetherdynamo and plate tectonics canoccur, both of which may be key to understanding the potential for a rich and detectablebiosphere.But understanding planetary interiors depends on understandingmatter under extreme pressures. This takes researchers into new regimes of physics which in turn, demand new methods. Material underMegabar pressures represents a frontier domain of plasma physics called Warm Dense Matter (WDM) which has recently become accessible via direct laboratory studies. In this white paper we review the state of exoplanet interior studies and the ability of High Energy Density Plasma (HEDP) WDM techniques to address critical open issues.
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- Award ID(s):
- 1725178
- PAR ID:
- 10174370
- Date Published:
- Journal Name:
- Baas
- Volume:
- 51
- Issue:
- 3
- ISSN:
- 2468-1083
- Page Range / eLocation ID:
- 36
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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