Related papers: A Limited Habitable Zone for Complex Life
The TRAPPIST-1 system provides an extraordinary opportunity to study multiple terrestrial extrasolar planets and their atmospheres. Here we use the National Center for Atmospheric Research Community Atmosphere Model version 4 to study the…
The field of astrobiology has made huge strides in understanding the habitable zones around stars (Stellar Habitable Zones) where life can begin, sustain its existence and evolve into complex forms. A few studies have extended this idea by…
We have shown that Earth-mass planets could survive in variously restricted regions of the habitable zones (HZs) of most of a sample of nine of the 93 main-sequence exoplanetary systems confirmed by May 2003. In a preliminary extrapolation…
With most planets and planetary candidates detected in the stellar habitable zone (HZ) being super-Earths and gas giants, rather than Earth-like planets, we naturally wonder if their moons could be habitable. The first detection of such an…
Young terrestrial planets can capture or outgas hydrogen-rich atmospheres with tens to hundreds of bars of H2, which persist for 100 Myrs or longer. Although the earliest habitable conditions on Earth and terrestrial exoplanets could thus…
We show that terrestrial planets in the habitable zones of M dwarfs older than $\sim$ 1 Gyr could have been in runaway greenhouses for several hundred Myr following their formation due to the star's extended pre-main sequence phase,…
The abundances of atmospheric carbon species--carbon dioxide (CO2), carbon monoxide (CO), and methane (CH4)--exert fundamental controls on the climate, redox state, and prebiotic environment of terrestrial planets. As exoplanet atmospheric…
Radial velocity surveys are now able to detect terrestrial planets at habitable distance from M-type stars. Recently, two planets with minimum masses below 10 Earth masses were reported in a triple system around the M-type star Gliese 581.…
Thousands of exoplanets orbit nearby stars, showcasing a remarkable diversity in mass, size, and orbits. With the James Webb Space Telescope now operational, we are observing exoplanet atmospheres and aiming to reach down to small,…
We have shown that Earth-mass planets could survive in variously restricted regions of the habitable zones (HZs) of most of a sample of nine of the 102 main-sequence exoplanetary systems confirmed by 25 September 2003. In a preliminary…
LHS 1140 b is a small planet orbiting in the habitable zone of its M4.5V dwarf host. Recent mass and radius constraints have indicated that it has either a thick H$_2$-rich atmosphere or substantial water by mass. Here we present a…
One of the most fundamental questions in exoplanetology is to determine whether a given planet is habitable. We estimate the relative likelihood of a planet's propensity towards habitability by considering key physical characteristics such…
Exoplanetary science is increasingly prioritizing efforts toward direct imaging of planetary systems, with emphasis on those that may enable the detection and characterization of potentially habitable exoplanets. The recent 2020 Astronomy…
High levels of X-ray and UV activity on young M dwarfs may drive rapid atmospheric escape on temperate, terrestrial planets orbiting within the liquid water habitable zone. However, secondary atmospheres on planets orbiting older, less…
Exoplanets orbiting M dwarfs present a valuable opportunity for their detection and atmospheric characterisation. This is evident from recent inferences of H$_2$O in such atmospheres, including that of the habitable-zone exoplanet K2-18b.…
The search for habitable environments and biomarkers in exoplanetary atmospheres is the holy grail of exoplanet science. The detection of atmospheric signatures of habitable Earth-like exoplanets is challenging due to their small…
In the search for life on Earth-like planets around other stars, the first (and likely only) information will come from the spectroscopic characterization of the planet's atmosphere. Of the countless number of chemical species terrestrial…
Efforts to spectrally characterize the atmospheric compositions of temperate terrestrial exoplanets orbiting M-dwarf stars with the James Webb Space Telescope (JWST) are now underway. Key molecular targets of such searches include O$_2$ and…
M dwarf stars, which have masses less than 60 per cent that of the Sun, make up 75 per cent of the population of the stars in the Galaxy [1]. The atmospheres of orbiting Earth-sized planets are observationally accessible via transmission…
Kepler-452b is currently the best example of an Earth-size planet in the habitable zone of a sun-like star, a type of planet whose number of detections is expected to increase in the future. Searching for biosignatures in the supposedly…