Related papers: Energy-limited escape revised
Hydrodynamic atmospheric escape plays a central role in shaping the demographics of small, close-in exoplanets. Two mechanisms have been proposed to drive mass loss: photoevaporation, powered by UV irradiation, and core-powered mass loss,…
Over the past decade, observations of evaporating exoplanets have become increasingly common, driven by the discovery of the near-infrared helium-triplet line as a powerful probe of atmospheric escape. This process significantly influences…
We explore atmospheric escape from close-in exoplanets with the highest mass loss rates. First, we locate the transition from stellar X-ray and UV-driven escape to rapid Roche lobe overflow, which occurs once the 10-100 nbar pressure level…
Atmospheric escape is key to explaining the long-term evolution of planets in our Solar System and beyond, and in the interpretation of atmospheric measurements. Hydrodynamic escape is generally thought to be driven by the flux of extreme…
The atmospheres of highly irradiated exoplanets are observed to undergo hydrodynamic escape. However, due to strong pressures, stellar winds can confine planetary atmospheres, reducing their escape. Here, we investigate under which…
Motivated by the trends found in the observed sample of extrasolar planets, this paper determines tidal equilibrium states for forming planetary systems --- subject to conservation of angular momentum, constant total mass, and fixed orbital…
Intense X-ray and ultraviolet stellar irradiation can heat and inflate the atmospheres of closely orbiting exoplanets, driving mass outflows that may be significant enough to evaporate a sizable fraction of the planet atmosphere over the…
Recent exoplanet statistics indicate that photo-evaporation has a great impact on the mass and bulk composition of close-in low-mass planets. While there are many studies addressing photo-evaporation of hydrogen-rich or water-rich…
Planetary habitability is in part determined by the atmospheric evolution of a planet; one key component of such evolution is escape of heavy ions to space. Ion loss processes are sensitive to the plasma environment of the planet, dictated…
The extra-solar planet HD209458b has been found to have an extended atmosphere of escaping atomic hydrogen (Vidal-Madjar et al. 2003), suggesting that ``hot Jupiters'' closer to their parent stars could evaporate. Here we estimate the…
A multi-fluid model for an atomic hydrogen-proton mixture in the upper atmosphere of extrosolar planet is presented when the continuity and momentum equations of each component have been already solved with an energy equation. The particle…
Strong ionization on close-in extrasolar giant planets suggests that their atmospheres may be affected by ion drag and resistive heating arising from wind-driven electrodynamics. Recent models of ion drag on these planets, however, are…
Accurately determining escape rates from a planet's atmosphere is critical for determining its evolution. Escape can be driven by upward thermal conduction of energy deposited well below the exobase, as well as by non-thermal processes…
Intrinsic magnetic fields have long been thought to shield planets from atmospheric erosion via stellar winds; however, the influence of the plasma environment on atmospheric escape is complex. Here we study the influence of a weak…
Photoionization heating from UV radiation incident on the atmospheres of hot Jupiters may drive planetary mass loss. We construct a model of escape that includes realistic heating and cooling, ionization balance, tidal gravity, and pressure…
We calculate the mass loss driven by MHD waves from hot Jupiters by using MHD simulations in one-dimensional flux tubes. If a gaseous planet has magnetic field, MHD waves are excited by turbulence at the surface, dissipate at the upper…
We have recently hit the milestone of 5,000 exoplanets discovered. In stark contrast with the Solar System, most of the exoplanets we know to date orbit extremely close to their host stars, causing them to lose copious amounts of gas…
We present a method to quantify the upper-limit of the energy transmitted from the intense stellar wind to the upper atmospheres of three of the Trappist-1 planets (e, f, and g). We use a formalism that treats the system as two…
It is now recognized that energetic stellar photon and particle radiation evaporates and erodes planetary atmospheres and controls upper atmospheric chemistry. Key exoplanet host stars will be too faint at X-ray wavelengths for accurate…
Despite the identification of a great number of Jupiter-like and Earth-like planets at close-in orbits, the number of "hot Neptunes" - the planets with 0.6-18 times of Neptune mass and orbital periods less than 3 days - turned out to be…