Extrasolar Planets


Detection of the Atmosphere of the 1.6 Earth Mass Exoplanet GJ 1132b

Detection of the Atmosphere of the 1.6 Earth Mass Exoplanet GJ 1132b

Detecting the atmospheres of low-mass low-temperature exoplanets is a high-priority goal on the path to ultimately detect biosignatures in the atmospheres of habitable exoplanets.


Cloud Formation in Carbon- and Oxygen-rich Environment

Cloud Formation in Carbon- and Oxygen-rich Environment

Recent observations indicate potentially carbon-rich exoplanet atmospheres. Spectral fitting methods for brown dwarfs and exoplanets have invoked the C/O ratio as additional parameter but carbon-rich cloud formation modeling is a challenge for the models applied.


Timing the Shadow of a Potentially Habitable Extrasolar Planet

Timing the Shadow of a Potentially Habitable Extrasolar Planet

A group of researchers from the National Astronomical Observatory of Japan (NAOJ), the University of Tokyo, and the Astrobiology Center among others has observed the transit of a potentially Earth-like extrasolar planet known as K2-3d using the MuSCAT instrument on the Okayama Astrophysical Observatory 188-cm telescope.


Atmospheric Habitable Zones in Y Dwarf Atmospheres

Atmospheric Habitable Zones in Y Dwarf Atmospheres

We use a simple organism lifecycle model to explore the viability of an atmospheric habitable zone (AHZ), with temperatures that could support Earth-centric life, which sits above an environment that does not support life.


On the Possibility of Habitable Trojan Planets in Binary Star Systems

On the Possibility of Habitable Trojan Planets in Binary Star Systems

Approximately 60 percent of all stars in the solar neighbourhood (up to 80 percent in our Milky Way) are members of binary or multiple star systems. This fact led to the speculations that many more planets may exist in binary systems than are currently known.


Effects of Variable Eccentricity on the Climate of an Earth-like World

Effects of Variable Eccentricity on the Climate of an Earth-like World

The Kepler era of exoplanetary discovery has presented the Astronomical community with a cornucopia of planetary systems very different from the one which we inhabit.


Rotation of Planets Hosting Atmospheric Tides: From Venus to Habitable Super-Earths

Rotation of Planets Hosting Atmospheric Tides: From Venus to Habitable Super-Earths

The competition between the torques induced by solid and thermal tides drives the rotational dynamics of Venus-like planets and super-Earths orbiting in the habitable zone of low-mass stars.


Vital Signs: Seismology of Ocean Worlds

Vital Signs: Seismology of Ocean Worlds

Ice covered ocean worlds are probably seismically active. Measuring that activity can provide information about global and local habitability.


Pressure-dependent water absorption cross sections for exoplanets and other atmospheres

Pressure-dependent water absorption cross sections for exoplanets and other atmospheres

Many atmospheres (cool stars, brown dwarfs, giant planets, extrasolar planets) are predominately composed of molecular hydrogen and helium.


Close-in, low-mass planet candidates and evidence of planet accretion in the solar twin HIP 68468

Close-in, low-mass planet candidates and evidence of planet accretion in the solar twin HIP 68468

[Methods]. We obtained high-precision radial velocities with HARPS on the ESO 3.6 m telescope and determined precise stellar elemental abundances (~0.01 dex) using MIKE spectra on the Magellan 6.5m telescope.


Low Mass Stars Likely Have Earth-sized Planets With Lots of Water

Low Mass Stars Likely Have Earth-sized Planets With Lots of Water

Computer simulations by astrophysicists at the University of Bern of the formation of planets orbiting in the habitable zone of low mass stars such as Proxima Centauri show that these planets are most likely to be roughly the size of the Earth and to contain large amounts of water.


Sub-milli-Kelvin Instruments - Radial Velocity Measurements: Tests with the Habitable-zone Planet Finder

Sub-milli-Kelvin Instruments - Radial Velocity Measurements: Tests with the Habitable-zone Planet Finder

Insufficient instrument thermo-mechanical stability is one of the many roadblocks for achieving 10cm/s Doppler radial velocity (RV) precision, the precision needed to detect Earth-twins orbiting Solar-type stars.


The Habitability of Planets Orbiting M-dwarf Stars

The Habitability of Planets Orbiting M-dwarf Stars

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 hotter, more luminous Sun-like stars.


A Population of Planetary Systems Characterized by Short-period, Earth-sized Planets

A Population of Planetary Systems Characterized by Short-period, Earth-sized Planets

We analyze data from the Quarter 1-17 Data Release 24 (Q1--Q17 DR24) planet candidate catalog from NASA's Kepler mission, specifically comparing systems with single transiting planets to systems with multiple transiting planets, and identify a distinct population of exoplanets with a necessarily distinct system architecture.


Tatooine's Future: The Eccentric Response of Kepler's Circumbinary Planets to Common-Envelope Evolution of their Host Stars

Tatooine's Future: The Eccentric Response of Kepler's Circumbinary Planets to Common-Envelope Evolution of their Host Stars

Inspired by the recent Kepler discoveries of circumbinary planets orbiting nine close binary stars, we explore the fate of the former as the latter evolve off the main sequence.


Ground-based Transit Observation of the Habitable-zone super-Earth K2-3d

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 the multi(grz)-band imager MuSCAT.


Kepler's Ultra-Short-Period Planets Formed Water-Poor

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 <1.5 Earth radii, indicating that they likely have rocky compositions.


Possible Internal Structures and Compositions of Proxima Centauri b

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.


The Space Weather of Proxima Centauri b

The Space Weather of Proxima Centauri b

A planet orbiting in the "habitable zone" of our closest neighboring star, Proxima Centauri, has recently been discovered, and the next natural question is whether or not Proxima b is "habitable".


The Pale Green Dot: A Method to Characterize Proxima Centauri b using Exo-Aurorae

The Pale Green Dot: A Method to Characterize Proxima Centauri b using Exo-Aurorae

We examine the feasibility of detecting auroral emission from the potentially habitable exoplanet Proxima Centauri b.



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