We show that terrestrial planets in the habitable zones of M dwarfs older than ∼ 1 Gyr could have been in runaway greenhouses for several hundred Myr following their formation […]
extrasolar
Posted inHabitable Zones
Climate Stability of Habitable Earth-like Planets
The carbon-silicate cycle regulates the atmospheric CO2 content of terrestrial planets on geological timescales through a balance between the rates of CO2 volcanic outgassing and planetary intake from rock weathering. […]
Posted inAstronomy & Telescopes, Exoplanets, -moons, -comets, Press Release
European Satellite Could Discover Thousands of Planets
Princeton University and Lund University researchers project that the recently launched European satellite Gaia could discover tens of thousands of planets during its five-year mission. In this image, the colored […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Water Trapping on Tidally Locked Terrestrial Planets Requires Special Conditions
Surface liquid water is essential for standard planetary habitability. Calculations of atmospheric circulation on tidally locked planets around M stars suggest that this peculiar orbital configuration lends itself to the […]
Posted inAstrochemistry, Exoplanets, -moons, -comets
Stellar Parameters and Chemical Abundances of 223 Evolved Stars With and Without Planets
We present fundamental stellar parameters and chemical abundances for a sample of 86 evolved stars with planets and for a control sample of 137 stars without planets. The analysis was […]
Posted inExoplanets, -moons, -comets, Habitable Zones
From Sub-Neptunes to Super-Earths: The Search for Habitable Worlds
During a live Google Hangout, three astrophysicists — Zachory Berta-Thompson, Bruce Macintosh and Marie-Eve Naud — discussed the huge variety of planets discovered so far, how close we are to […]
Posted inExoplanets, -moons, -comets
Accretion and Differentiation of the Terrestrial Planets
In order to test planetary accretion and differentiation scenarios, we integrated a multistage core-mantle differentiation model with N-body accretion simulations. Impacts between embryos and planetesimals result in magma ocean formation […]
Posted inExoplanets, -moons, -comets
Geothermal Heating Enhances Atmospheric Asymmetries on Synchronously Rotating Planets
Earth-like planets within the liquid water habitable zone of M type stars may evolve into synchronous rotators. On these planets, the sub-stellar hemisphere experiences perpetual daylight while the opposing anti-stellar […]
Posted inExoplanets, -moons, -comets
Hubble Search for a Sub-Earth-Sized Exoplanet in the GJ 436 System
The detection of small planets orbiting nearby stars is an important step towards the identification of Earth twins. In previous work using the Spitzer Space Telescope, we found evidence to […]
Posted inAstrochemistry, Habitable Zones
The Ancient Heritage of Water Ice in the Solar System
Identifying the source of Earth’s water is central to understanding the origins of life-fostering environments and to assessing the prevalence of such environments in space. Water throughout the solar system […]