TY - JOUR

T1 - Consequences of Tidal Dissipation in a Putative Venusian Ocean

AU - Green, J,. A. Mattias

AU - Way, Michael J.

AU - Barnes, Rory

N1 - J.A.M.G. received funding from NERC, grant NE/I030224/1. R.B. acknowledges support from NASA grant NNX15AN35G. This work was supported by the NASA Astrobiology Program through collaborations arising from our participation in the Nexus for Exoplanet System Science, and by the NASA Planetary Atmospheres Program. M.J.W. is thankful for support from the Goddard Space Flight Center's Sellers Exoplanet Environments Collaboration (SEEC), which is funded by the NASA Planetary Science Division's Internal Scientist Funding Model. Simulations were done using Supercomputing Wales and their support is greatly appreciated.

PY - 2019/5/10

Y1 - 2019/5/10

N2 - The solar tide in an ancient Venusian ocean is simulated using a dedicated numerical tidal model. Simulations with varying ocean depth and rotational periods ranging from -243 to 64 sidereal Earth days are used to calculate the tidal dissipation rates and associated tidal torque. The results show that the tidal dissipation could have varied by more than 5 orders of magnitude, from 0.001--780 Gigawatts, depending on rotational period and ocean depth. The associated tidal torque is about 2 orders of magnitude below the present day Venusian atmospheric torque, and could change the Venusian day length by up to 72 days per million years depending on rotation rate. Consequently, an ocean tide on ancient Venus could have had significant effects on the rotational history of the planet. These calculations have implications for the rotational periods of similarly close-in exoplanetary worlds and the location of the inner edge of the liquid water habitable zone

AB - The solar tide in an ancient Venusian ocean is simulated using a dedicated numerical tidal model. Simulations with varying ocean depth and rotational periods ranging from -243 to 64 sidereal Earth days are used to calculate the tidal dissipation rates and associated tidal torque. The results show that the tidal dissipation could have varied by more than 5 orders of magnitude, from 0.001--780 Gigawatts, depending on rotational period and ocean depth. The associated tidal torque is about 2 orders of magnitude below the present day Venusian atmospheric torque, and could change the Venusian day length by up to 72 days per million years depending on rotation rate. Consequently, an ocean tide on ancient Venus could have had significant effects on the rotational history of the planet. These calculations have implications for the rotational periods of similarly close-in exoplanetary worlds and the location of the inner edge of the liquid water habitable zone

KW - planets and satellites: dynamical evolution and stability

U2 - 10.3847/2041-8213/ab133b

DO - 10.3847/2041-8213/ab133b

M3 - Article

VL - 876

JO - The Astrophysical Journal Letters

JF - The Astrophysical Journal Letters

SN - 2041-8213

IS - 2

M1 - L22

ER -