Related papers: Characterizing Exoplanet Habitability
The tidal heating of hypothetical rocky (or terrestrial) extra-solar planets spans a wide range of values depending on stellar masses and initial orbits. Tidal heating may be sufficiently large (in many cases, in excess of radiogenic…
We propose the concept of a "Galactic Habitable Zone" (GHZ). Analogous to the Circumstellar Habitable Zone (CHZ), the GHZ is that region in the Milky Way where an Earth-like planet can retain liquid water on its surface and provide a…
'Most habitable worlds in the cosmos will have no remotely detectable signs of life' is proposed as a biological hypothesis to be tested in studies of exoplanets. Habitable planets could be discovered elsewhere in the Universe, yet there…
Theory and observation for the search for life on exoplanets via atmospheric "biosignature gases" is accelerating, motivated by the capabilities of the next generation of space- and ground-based telescopes. The most observationally…
Planetary obliquity (axial tilt) plays an important role in regulating the climate evolution and habitability of water-covered planets. Despite the suspicion of large obliquities in several exoplanetary systems, this phenomenon remains hard…
We investigate how well the Large Interferometer for Exoplanets (LIFE) mission concept can detect habitable conditions on exoplanets through the presence of atmospheric water vapor as a proxy for surface oceans. We model the atmosphere of a…
The field of exoplanets is quickly expanding from just the detection of new planets and the measurement of their most basic parameters, such as mass, radius and orbital configuration, to the first measurements of their atmospheric…
Over the past two decades, enormous advances in the detection of exoplanets have taken place. Currently, we have discovered hundreds of earth-sized planets, several of them within the habitable zone of their star. In the coming years, the…
The habitable zone (HZ) is commonly defined as the range of distances from a host star within which liquid water, a key requirement for life, may exist on a planet's surface. Substantially more CO2 than present in Earth's modern atmosphere…
The investigation of planets around other stars began with the study of gas giants, but is now extending to the discovery and characterization of super-Earths and terrestrial planets. Motivated by this observational tide, we survey the…
How can scientists conclude with high confidence that an exoplanet hosts life? As telescopes come on line over the next 20 years that can directly observe photons from terrestrial exoplanets, this question will dictate the activities of…
We explore the impact of obliquity variations on planetary habitability in hypothetical systems with high mutual inclination. We show that large amplitude, high frequency obliquity oscillations on Earth-like exoplanets can suppress the…
Liquid water is one of the most important materials affecting the climate and habitability of a terrestrial planet. Liquid water vaporizes entirely when planets receive insolation above a certain value, which is called the runaway…
Here, we evaluate our nearest planetary neighbor, Venus, as an exemplar of the runaway greenhouse state that bounds the inner edge of the habitable zone. Despite its current hellish surface environment, Venus may once have been habitable…
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…
A planet's climate can be strongly affected by its orbital eccentricity and obliquity. Here we use a 1-dimensional energy balance model modified to include a simple runaway greenhouse (RGH) parameterization to explore the effects of these…
Our present-day atmosphere is often used as an analog for potentially habitable exoplanets, but Earth's atmosphere has changed dramatically throughout its 4.5 billion year history. For example, molecular oxygen is abundant in the atmosphere…
The current search for habitable planets has focused on Earth-like conditions of mass, volatile content and orbit. However, rocky planets following eccentric orbits, and drier than the Earth, may be a more common phenomenon in the Universe.…
Water is fundamental to our understanding of the evolution of planetary systems and the delivery of volatiles to the surfaces of potentially habitable planets. Yet, we currently have essentially no facilities capable of observing this key…
Whether binaries can harbor potentially habitable planets depends on several factors including the physical properties and the orbital characteristics of the binary system. While the former determines the location of the habitable zone…