Tidal locking of habitable exoplanets

  title={Tidal locking of habitable exoplanets},
  author={Rory Barnes},
  journal={Celestial Mechanics and Dynamical Astronomy},
  • R. Barnes
  • Published 9 August 2017
  • Physics
  • Celestial Mechanics and Dynamical Astronomy
Potentially habitable planets can orbit close enough to their host star that the differential gravity across their diameters can produce an elongated shape. Frictional forces inside the planet prevent the bulges from aligning perfectly with the host star and result in torques that alter the planet’s rotational angular momentum. Eventually the tidal torques fix the rotation rate at a specific frequency, a process called tidal locking. Tidally locked planets on circular orbits will rotate… Expand
Habitability of polar regions in tidally locked extrasolar planet near the M-Dwarf stars
Since the launch of Kepler and Hubble more than a decade ago, we have come a long way in the quest to find a potentially habitable exoplanet. To date, we have already discovered more than 4000Expand
Effects of Spin–Orbit Resonances and Tidal Heating on the Inner Edge of the Habitable Zone
Much attention has been given to the climate dynamics and habitable boundaries of synchronously rotating planets around low mass stars. However, other rotational states are possible, includingExpand
On The Lack of Circumbinary Planets Orbiting Isolated Binary Stars
We outline a mechanism that explains the observed lack of circumbinary planets (CBPs) via coupled stellar-tidal evolution of isolated binary stars. Tidal forces between low-mass, short-period binaryExpand
Tidal response of rocky and ice-rich exoplanets
The amount of detected planets with sizes comparable to that of the Earth is increasing drastically. Most of the Earth-size planet candidates orbit at close distances from their central star, andExpand
Interior Structures and Tidal Heating in the TRAPPIST-1 Planets
With seven planets, the TRAPPIST-1 system has the largest number of exoplanets discovered in a single system so far. The system is of astrobiological interest, because three of its planets orbit inExpand
Exomoons in the Habitable Zones of M Dwarfs
M dwarfs host most of the exoplanets in the local Milky Way. Some of these planets, ranging from sub-Earths to super-Jupiters, orbit in their stars' habitable zones (HZs), although many likelyExpand
Non-tidal Coupling of the Orbital and Rotational Motions of Extended Bodies.
The orbital motions and spin-axis rotations of extended bodies are traditionally considered to be coupled only by tidal mechanisms. The orbit-spin coupling hypothesis supplies an additionalExpand
Stabilization of Dayside Surface Liquid Water via Tropopause Cold Trapping on Arid Slowly Rotating Tidally Locked Planets
Terrestrial-type exoplanets orbiting nearby red dwarf stars (M-dwarfs) are among the best targets for atmospheric characterization and biosignature searches in the near future. Recent evolutionaryExpand
Tidally Induced Radius Inflation of Sub-Neptunes
Recent work suggests that many short-period super-Earth and sub-Neptune planets may have significant spin axis tilts ("obliquities"). When planets are locked in high-obliquity states, the tidalExpand
Sensitivity of the Atmospheric Water Cycle within the Habitable Zone of a Tidally Locked, Earth-like Exoplanet
Synchronously orbiting, tidally-locked exoplanets with a dayside facing their star and a permanently dark nightside orbiting dim stars are prime candidates for habitability. Simulations of theseExpand


Tidal obliquity evolution of potentially habitable planets
Context. Stellar insolation has been used as the main constraint on a planet’s potential habitability. However, as more Earth-like planets are discovered around low-mass stars (LMSs), aExpand
Tides and the evolution of planetary habitability.
The tidal evolution of hypothetical terrestrial planets around low-mass stars is calculated and it is shown that tides can evolve planets past the inner edge of the habitable zone, sometimes in less than 1 billion years. Expand
Forced libration of tidally synchronized planets and moons
Tidal dissipation of kinetic energy, when it is strong enough, tends to synchronize the rotation of planets and moons with the mean orbital motion, or drive it into long-term stable spin-orbitExpand
We revisit the tidal stability of extrasolar systems harboring a transiting planet and demonstrate that, independently of any tidal model, none, but one (HAT-P-2b) of these planets has a tidalExpand
Tides, planetary companions, and habitability: habitability in the habitable zone of low-mass stars
Earth-scale planets in the classical habitable zone (HZ) are more likely to be habitable if they possess active geophysics. Without a constant internal energy source, planets cool as they age,Expand
The distribution of the orbits of close-in exoplanets shows evidence for ongoing removal and destruction by tides. Tides raised on a planet's host star cause the planet's orbit to decay, even afterExpand
Tidal Heating of Earth-like Exoplanets around M Stars: Thermal, Magnetic, and Orbital Evolutions
A thermal-orbital evolution model calibrated to Earth that couples tidal dissipation, with a temperature-dependent Maxwell rheology, to orbital circularization and migration is developed and identifies a peak in the internal dissipation rate as the mantle passes through a viscoelastic state at mantle temperatures near 1800 K. Expand
Tidal Evolution of the Planetary System around HD 83443
Two planets with an orbital period ratio of approximately 10:1 have been discovered around the star HD 83443. The inner and more massive planet, HD 83443b, has the smallest semimajor axis among allExpand
The inner edge of the habitable zone for synchronously rotating planets around low-mass stars using general circulation models
Terrestrial planets at the inner edge of the habitable zone of late-K and M-dwarf stars are expected to be in synchronous rotation, as a consequence of strong tidal interactions with their hostExpand
Exomoon habitability constrained by illumination and tidal heating.
This work identifies combinations of physical and orbital parameters for which radiative and tidal heating are strong enough to trigger a runaway greenhouse on exomoons and defines a circumplanetary "habitable edge". Expand