The prospects for the habitability of M-dwarf planets have long been debated, due to key differences between the unique stellar and planetary environments around these low-mass stars, as compared to […]
extrasolar
Posted inHabitable Zones, Press Release
Transition to a Moist Greenhouse With CO2 and Solar Forcing
Water-rich planets such as Earth are expected to become eventually uninhabitable, because liquid water does not remain stable at the surface as surface temperatures increase with the solar luminosity over […]
Posted inExoplanets, -moons, -comets, Habitable Zones, Press Release
Ground-based Transit Observation of the Habitable-zone super-Earth K2-3d
We report the first ground-based transit observation of K2-3d, a 1.5 R_Earth planet supposedly within the habitable zone around a bright M-dwarf host star, using the Okayama 188-cm telescope and […]
Posted inExoplanets, -moons, -comets, Habitable Zones
Kepler's Ultra-Short-Period Planets Formed Water-Poor
Recent surveys have uncovered an exciting new population of ultra-short-period (USP) planets with orbital periods less than a day. These planets typically have radii 2 Earth radii today, which is […]
Posted inExoplanets, -moons, -comets, Press Release, Proxima Centauri
Possible Internal Structures and Compositions of Proxima Centauri b
We explore the possible Proxima Centauri b’s interiors assuming the planet belongs to the class of dense solid planets (rocky with possible addition of water) and derive the corresponding radii. […]
Posted inExoplanets, -moons, -comets, Press Release, Water/Hycean Worlds & Oceanography
The Abundance of Atmospheric CO2 in Ocean Exoplanets: A Novel CO2 Deposition Mechanism
We consider super-Earth sized planets which have a water mass fraction that is large enough to form an external mantle composed of high pressure water ice polymorphs and that lack […]
Posted inExoplanets, -moons, -comets, Press Release
Terrestrial-type Planet Formation: Comparing Different Types of Initial Conditions
To study the terrestrial-type planet formation during the post oligarchic growth, the initial distributions of planetary embryos and planetesimals used in N-body simulations play an important role. Most of these […]
Posted inExoplanets, -moons, -comets, Press Release
New Indexing and Surface Temperature Analysis of Exoplanets
Study of exoplanets is the holy grail of present research in planetary sciences and astrobiology. Analysis of huge planetary data from space missions such as CoRoT and Kepler is directed […]
Posted inBiosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Press Release
Biological Fluorescence as a Temporal Biosignature for Flare Star Worlds
Habitability for planets orbiting active stars has been questioned. Especially, planets in the Habitable Zone (HZ) of M-stars, like our closest star Proxima Centauri, experience temporal high-ultraviolet (UV) radiation. The […]
Posted inExoplanets, -moons, -comets, Habitable Zones, Press Release, Proxima Centauri
Rocky Planet Found in Habitable Zone of Proxima Centauri
An international team of astronomers including Carnegie’s Paul Butler has found clear evidence of a planet orbiting Proxima Centauri, the closest star to our solar system. The new world, designated […]