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Title: The Fuzziness of Giant Planets’ Cores

Abstract

Giant planets are thought to have cores in their deep interiors, and the division into a heavy-element core and hydrogen–helium envelope is applied in both formation and structure models. We show that the primordial internal structure depends on the planetary growth rate, in particular, the ratio of heavy elements accretion to gas accretion. For a wide range of likely conditions, this ratio is in one-to-one correspondence with the resulting post-accretion profile of heavy elements within the planet. This flux ratio depends sensitively on the assumed solid-surface density in the surrounding nebula. We suggest that giant planets’ cores might not be distinct from the envelope and includes some hydrogen and helium, and the deep interior can have a gradual heavy-element structure. Accordingly, Jupiter’s core may not be well defined. Accurate measurements of Jupiter’s gravitational field by Juno could put constraints on Jupiter’s core mass. However, as we suggest here, the definition of Jupiter’s core is complex, and the core’s physical properties (mass, density) depend on the actual definition of the core and on the planet’s growth history.

Authors:
 [1];  [2]
  1. Institute for Computational Science, University of Zurich, Zurich (Switzerland)
  2. Division of Geological and Planetary Sciences, Caltech, Pasadena, CA (United States)
Publication Date:
OSTI Identifier:
22654489
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 840; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DENSITY; GRAVITATIONAL FIELDS; HELIUM; HYDROGEN; JUPITER PLANET; LIMITING VALUES; MASS; NEBULAE; SATELLITES

Citation Formats

Helled, Ravit, and Stevenson, David. The Fuzziness of Giant Planets’ Cores. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA6D08.
Helled, Ravit, & Stevenson, David. The Fuzziness of Giant Planets’ Cores. United States. doi:10.3847/2041-8213/AA6D08.
Helled, Ravit, and Stevenson, David. Mon . "The Fuzziness of Giant Planets’ Cores". United States. doi:10.3847/2041-8213/AA6D08.
@article{osti_22654489,
title = {The Fuzziness of Giant Planets’ Cores},
author = {Helled, Ravit and Stevenson, David},
abstractNote = {Giant planets are thought to have cores in their deep interiors, and the division into a heavy-element core and hydrogen–helium envelope is applied in both formation and structure models. We show that the primordial internal structure depends on the planetary growth rate, in particular, the ratio of heavy elements accretion to gas accretion. For a wide range of likely conditions, this ratio is in one-to-one correspondence with the resulting post-accretion profile of heavy elements within the planet. This flux ratio depends sensitively on the assumed solid-surface density in the surrounding nebula. We suggest that giant planets’ cores might not be distinct from the envelope and includes some hydrogen and helium, and the deep interior can have a gradual heavy-element structure. Accordingly, Jupiter’s core may not be well defined. Accurate measurements of Jupiter’s gravitational field by Juno could put constraints on Jupiter’s core mass. However, as we suggest here, the definition of Jupiter’s core is complex, and the core’s physical properties (mass, density) depend on the actual definition of the core and on the planet’s growth history.},
doi = {10.3847/2041-8213/AA6D08},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 840,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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