The dynamics of systems of two and three planets, initially placed on circular and nearly coplanar orbits, is explored in the proximity of their stability limit. The evolution of a […]
astro-ph.EP]
Posted inExoplanets, -moons, -comets
On the Abundance of Circumbinary Planets
Circumbinary planets have been the subject of much recent work, providing both simulations and new discoveries. We present the first observationally based determination of the rate of occurrence of these […]
Posted inBiosignatures & Paleobiology, Exoplanets, -moons, -comets, Plant Biology
Prospects for Detecting Oxygen, Water, and Chlorophyll in an Exo-Earth
The goal of finding and characterizing nearby Earth-like planets is driving many NASA high-contrast flagship mission concepts, the latest of which is known as the Advanced Technology Large-Aperture Space Telescope […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Strong Dependence of the Inner Edge of the Habitable Zone on Planetary Rotation Rate
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 […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Habitable Zones Around Main-Sequence Stars: Dependence on Planetary Mass
The ongoing discoveries of extrasolar planets are unveiling a wide range of terrestrial mass (size) planets around their host stars. In this letter, we present estimates of habitable zones (HZs) […]
Posted inExoplanets, -moons, -comets
N-body Simulations of Terrestrial Planet Formation under the Influence of a Hot Jupiter
We investigate the formation of multiple-planet systems in the presence of a hot Jupiter using extended N-body simulations that are performed simultaneously with semi-analytic calculations. Our primary aims are to […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Earth-like Habitats in Planetary Systems
Understanding the concept of habitability is related to an evolutionary knowledge of the particular planet-in-question. Additional indications so-called “systemic aspects” of the planetary system as a whole governs a particular […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Formation, Tidal Evolution and Habitability of the Kepler-186 System
The Kepler-186 system consists of five planets orbiting an early-M dwarf. The planets have physical radii of 1.0-1.50 R⊕ and orbital periods of 4 to 130 days. The 1.1 R⊕ Kepler-186f […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Effect of Planetary Illumination on Climate Modelling of Earthlike Exomoons
From analytical studies of tidal heating, eclipses and planetary illumination, it is clear that the exomoon habitable zone (EHZ) – the set of moon and host planet orbits that permit […]
Posted inAstrochemistry, Radiation
Radiolysis of Amino Acids by Heavy and Energetic Cosmic Ray Analogs in Simulated Space Environments
In this work, we studied the stability of the glycine molecule in the crystalline zwitterion form, known as {alpha}-glycine (+ NH3 CH2 COO− ) under action of heavy cosmic ray […]