Related papers: An observational signature of evolved oceans on ex…
Stellar wind and photon radiation interactions with a planet can cause atmospheric depletion, which may have a potentially catastrophic impact on a planet's habitability. While the implications of photoevaporation on atmospheric erosion…
A variety of terrestrial planets with different physical parameters and exotic atmospheres might plausibly exist outside our Solar System, waiting to be detected by the next generation of space-exploration missions. Some of these planets…
Hot gas giant exoplanets can lose part of their atmosphere due to strong stellar irradiation, affecting their physical and chemical evolution. Studies of atmospheric escape from exoplanets have mostly relied on space-based observations of…
The phase or orbital light curves of extrasolar terrestrial planets in reflected or emitted light will contain information about their atmospheres and surfaces complementary to data obtained by other techniques such as spectrosopy. We show…
Atomic hydrogen escaping from the extrasolar giant planet HD209458b provides the largest observational signature ever detected for an extrasolar planet atmosphere. In fact, the upper atmosphere of this planet is evaporating. Observational…
Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of…
(Abridged) The existence of an extended neutral hydrogen exosphere around small planets can be used as an evidence for the presence of water in their lower atmosphere but, to date, such feature has not been securely detected in rocky…
The population of known low- to intermediate-mass exoplanets shows a large spread in densities, which is believed to be due to the diversity of planetary atmospheres and thus controlled by planetary atmospheric mass loss. One of the main…
Thousands of planets beyond our solar system have been discovered to date, dozens of which are rocky in composition and are orbiting within the circumstellar habitable zone of their host star. The next frontier in life detection beyond our…
Exoplanet atmospheres are known to be vulnerable to mass loss through irradiation by stellar X-ray and extreme-ultraviolet emission. We investigate how this high-energy irradiation varies with time by combining an empirical relation…
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…
Recent observations of the Earth's exosphere revealed the presence of an extended hydrogenic component that could reach distances beyond 40 planetary radii. Detection of similar extended exospheres around Earth-like exoplanets could reveal…
X-rays and extreme ultraviolet radiation impacting on a gas produce a variety of effects that, depending on the electron content, may provide a significant heating of the illuminated region. In a planetary atmosphere of solar composition,…
We propose that astronomers will be eventually be able to discriminate between extrasolar Earth-like planets with surface oceans and those without using the shape of phase light curves in the visible and near-IR spectrum. We model the…
During the post-main sequence phase of stellar evolution the orbital distance of the habitable zone, which allows for liquid surface water on terrestrial planets, moves out past the system's original frost line, providing an opportunity for…
The discovery of thousands of highly irradiated, low-mass, exoplanets has led to the idea that atmospheric escape is an important process that can drive their evolution. Of particular interest is the inference from recent exoplanet…
Exoplanets with substantial Hydrogen/Helium atmospheres have been discovered in abundance, many residing extremely close to their parent stars. The extreme irradiation levels these atmospheres experience causes them to undergo hydrodynamic…
Atmospheric escape from close-in Neptunes and hot Jupiters around sun-like stars driven by extreme ultraviolet (EUV) irradiation plays an important role in the evolution of exo-planets and in shaping their ensemble properties. Intermediate…
Escaping exoplanet atmospheres have been observed as deep transit signatures in a few specific spectral lines. Detections have been made in the hydrogen Ly-$\alpha$ line, the metastable helium line at 10830 {\AA} and some UV lines of…
Extrasolar planets appear in a chemical diversity unseen in our own solar system. Despite their atmospheres being cold, continuous and transient plasma processes do affect these atmosphere where clouds form with great efficiency. Clouds can…