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Formation of exoplanetary satellites by pull-down capture.

ABSTRACT: The large size and wide orbit of the recently announced exomoon candidate Kepler-1625b-i are hard to explain within traditional theories of satellite formation. We show that these properties can be reproduced if the satellite began as a circumstellar co-orbital body with the original core of the giant planet Kepler-1625b. This body was then drawn down into a circumplanetary orbit during the rapid accretion of the giant planet gaseous envelope, a process termed "pull-down capture." Our numerical integrations demonstrate the stability of the original configuration and the capture process. In this model, the exomoon Kepler-1625b-i is the protocore of a giant planet that never accreted a substantial gas envelope. Different initial conditions can give rise to capture into other co-orbital configurations, motivating the search for Trojan-like companions to this and other giant planets.

SUBMITTER: Hansen BMS

PROVIDER: S-EPMC6774722 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Formation of exoplanetary satellites by pull-down capture.

Hansen Bradley M S BMS

Science advances 20191002 10

The large size and wide orbit of the recently announced exomoon candidate Kepler-1625b-i are hard to explain within traditional theories of satellite formation. We show that these properties can be reproduced if the satellite began as a circumstellar co-orbital body with the original core of the giant planet Kepler-1625b. This body was then drawn down into a circumplanetary orbit during the rapid accretion of the giant planet gaseous envelope, a process termed "pull-down capture." Our numerical ...[more]

PMID: 31616785

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Dataset Information

Formation of exoplanetary satellites by pull-down capture.

Publications

Formation of exoplanetary satellites by pull-down capture.

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