Tides Between the TRAPPIST-1 Planets
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Author
Matsuyama, Isamu
Affiliation
Univ Arizona, Lunar & Planetary LabIssue Date
2019-04-10Keywords
gravitationplanets and satellites
dynamical evolution and stability
planets and satellites
individual (TRAPPIST-1g)
planets and satellites
interiors
planets and satellites
terrestrial planets
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IOP PUBLISHING LTDCitation
Hay, H. C., & Matsuyama, I. (2019). Tides between the TRAPPIST-1 planets. The Astrophysical Journal, 875(1), 22.Journal
ASTROPHYSICAL JOURNALRights
Copyright © 2019. The American Astronomical Society. All rights reserved.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
The TRAPPIST-1 system is sufficiently closely packed that tides raised by one planet on another are significant. We investigate whether this source of tidal heating is comparable to eccentricity tides raised by the star. Assuming a homogeneous body with a Maxwell rheology, we find that energy dissipation from stellar tides always dominates over that from planet–planet tides across a range of viscosities. TRAPPIST-1 g may experience the greatest proportion of planet–planet tidal heating, where it can account for between 2% and 20% of the total amount of tidal heating, for high-viscosity (1021 Pa s) and low-viscosity (1014 Pa s) regimes, respectively. If planet–planet tidal heating is to exceed that from stellar eccentricity tides, orbital eccentricities must be no more than e = 10−3–10−4 for most of the TRAPPIST-1 planets.ISSN
1538-4357Version
Final published versionSponsors
National Aeronautics and Space Agency (NASA) through the Habitable Worlds program [NNX15AQ88G]Scopus Count
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