Related papers: A Gaian Habitable Zone
Observations of exoplanets and protoplanetary disks show that binary stellar systems can host planets in stable orbits. Given the high binary fraction among stars, the contribution of binary systems to Galactic habitability should be…
In exoplanet research, the focus is increasingly on identifying Earth analogs, planets similar in density and habitability potential. As the number of rocky exoplanets grows, parallel discussions have emerged on system architectures and…
In this paper we introduce some simple models, based on rolling dice, to explore mechanisms proposed to explain planetary habitability. The idea is to study these selection mechanisms in an analytically tractable setting, isolating their…
Definition of habitability depends on the organisms under consideration. One way to determine habitability of some environment is to compare its certain parameters to environments where extremophilic micro-organisms thrive on Earth. We can…
In recent years, numerical models that were developed for Earth have been adapted to study exoplanetary climates to understand how the broad range of possible exoplanetary properties affects their climate state. The recent discovery and…
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…
A rigorous definition of the habitable zone and its dependence on planetary properties is part of the search for habitable exoplanets. In this work, we use the general circulation model ExoCAM to determine how the inner edge of the…
A key goal of the Kepler mission is the discovery of Earth-size transiting planets in "habitable zones" where stellar irradiance maintains a temperate climate on an Earth-like planet. Robust estimates of planet radius and irradiance require…
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 4000 exoplanets most of which are not suitable for…
Orbital phase-dependent variations in thermal emission and reflected stellar energy spectra can provide meaningful constraints on the climate states of terrestrial extrasolar planets orbiting M dwarf stars. Spatial distributions of water…
The detection of many extrasolar gas giants with high eccentricities indicates that dynamical instabilities in planetary systems are common. These instabilities can alter the orbits of gas giants as well as the orbits of terrestrial planets…
With more and more exoplanets being detected, it is paid closer attention to whether there are lives outside solar system. We try to obtain habitable zones and the probability distribution of terrestrial planets in habitable zones around…
The aim of this paper is to underline conditions necessary for the emergence and development of life. They are placed at local planetary scale, at Galactic scale and within the cosmological evolution, as pointed out by the Anthropic…
A star will become brighter and brighter with stellar evolution, and the distance of its habitable zone will become farther and farther. Some planets outside the habitable zone of a host star during the main sequence phase may enter the…
Planets residing in circumstellar habitable zones (CHZs) offer our best opportunities to test hypotheses of life's potential pervasiveness and complexity. Constraining the precise boundaries of habitability and its observational…
The liquid water habitable zone (HZ) describes the orbital distance at which a terrestrial planet can maintain above-freezing conditions through regulation by the carbonate-silicate cycle. Recent calculations have suggested that planets in…
Planetary rotation rate is a key parameter in determining atmospheric circulation and hence the spatial pattern of clouds. Since clouds can exert a dominant control on planetary radiation balance, rotation rate could be critical for…
We discuss the possibility of screening the atmosphere of exomoons for habitability. We concentrate on Earth-like satellites of extrasolar giant planets (EGP) which orbit in the Habitable Zone of their host stars. The detectability of…
Planets similar to Earth - but slightly more irradiated - are expected to enter into a runaway greenhouse state, where all surface water rapidly evaporates, forming an optically thick H2O-dominated atmosphere. For Earth, this extreme…
We use a probability theory framework to discuss the search for biosignatures. This perspective allows us to analyse the potential for different biosignatures to provide convincing evidence of extraterrestrial life and to formalise…