# Consequences of Tidal Dissipation in a Putative Venusian Ocean

## TL;DR

This study models tidal dissipation in a hypothetical ancient Venusian ocean, revealing significant variability in energy loss and potential impacts on Venus's rotational history and habitability zone boundaries.

## Contribution

It provides the first detailed numerical analysis of tidal dissipation effects on Venus's rotation and explores implications for exoplanet habitability.

## Key findings

- Tidal dissipation varies by over 5 orders of magnitude depending on ocean depth and rotation.
- Tidal torque could alter Venus's day length by up to 72 days per million years.
- Implications for the rotational evolution of Venus and similar exoplanets.

## Abstract

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.