Extrasolar Planets


Life on an Aquaplanet

Life on an Aquaplanet

An MIT study finds an exoplanet, tilted on its side, could still be habitable if covered in ocean.


What Asteroseismology Can Do for Exoplanets

What Asteroseismology Can Do for Exoplanets

We describe three useful applications of asteroseismology in the context of exoplanet science: (1) the detailed characterisation of exoplanet host stars; (2) the measurement of stellar inclinations; and (3) the determination of orbital eccentricity from transit duration making use of asteroseismic stellar densities.


The Occurrence of Earth-Like Planets Around Other Stars

The Occurrence of Earth-Like Planets Around Other Stars

The quantity η⊕, the number density of planets per star per logarithmic planetary radius per logarithmic orbital period at one Earth radius and one year period, describes the occurrence of Earth-like extrasolar planets.


The Habitable Zones of Pre-Main-Sequence Stars

The Habitable Zones of Pre-Main-Sequence Stars

We calculate the pre-main-sequence HZ for stars of spectral classes F to M. The spatial distribution of liquid water and its change during the pre-main-sequence phase of protoplanetary systems is important in understanding how planets become habitable.


Finding Infant Earths and Potential Life Just Got Easier

Finding Infant Earths and Potential Life Just Got Easier

Among the billions and billions of stars in the sky, where should astronomers look for infant Earths where life might develop?


Dynamics and Habitability in Binary Star Systems

Dynamics and Habitability in Binary Star Systems

Determining planetary habitability is a complex matter, as the interplay between a planet's physical and atmospheric properties with stellar insolation has to be studied in a self consistent manner.


Looking for Tatooines

Looking for Tatooines

A key discovery of the Kepler mission is of the circumbinary planets known as "Tatooines", which appear to be well aligned with their host stars' orbits.


Mirage Earth Exoplanets May Have Burned Away Chances for Life

Mirage Earth Exoplanets May Have Burned Away Chances for Life

Planets orbiting close to low-mass stars - easily the most common stars in the universe - are prime targets in the search for extraterrestrial life.


Dynamics of Exoplanetary Systems, Links to Their Habitability

Dynamics of Exoplanetary Systems, Links to Their Habitability

Our knowledge of planets' orbital dynamics, which was based on Solar System studies, has been challenged by the diversity of exoplanetary systems.


Ground-Based Detection of Super-Earth Transit Paves Way to Remote Sensing of Small Exoplanets

Ground-Based Detection of Super-Earth Transit Paves Way to Remote Sensing of Small Exoplanets

Astronomers have measured the passing of a super-Earth in front of a bright, nearby Sun-like star using a ground-based telescope for the first time.


Ground-Based Transit Observations of the Super-Earth 55 Cnc e

Ground-Based Transit Observations of the Super-Earth 55 Cnc e

We report the first ground-based detections of the shallow transit of the super-Earth exoplanet 55 Cnc e using a 2-meter-class telescope.


Dynamical Stability Study of Kepler Circumbinary Planetary Systems With One Planet

Dynamical Stability Study of Kepler Circumbinary Planetary Systems With One Planet

To date, 17 circumbinary planets have been discovered. In this paper, we focus our attention on the stability of the Kepler circumbinary planetary systems with only one planet, i.e. Kepler-16, Kepler-34, Kepler-35, Kepler-38, Kepler-64 and Kepler-413.


Extreme Water Loss and Abiotic O2 Buildup On Planets Throughout the Habitable Zones of M Dwarfs

Extreme Water Loss and Abiotic O2 Buildup On Planets Throughout the Habitable Zones of M Dwarfs

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 due to the star's extended pre-main sequence phase, provided they form with abundant surface water.


European Satellite Could Discover Thousands of Planets

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.


Water Trapping on Tidally Locked Terrestrial Planets Requires Special Conditions

Water Trapping on Tidally Locked Terrestrial Planets Requires Special Conditions

Surface liquid water is essential for standard planetary habitability.


Stellar Parameters and Chemical Abundances of 223 Evolved Stars With and Without Planets

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.


From Sub-Neptunes to Super-Earths: The Search for Habitable Worlds

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 being able to see other Earth-like planets, and all that remains unknown.


Accretion and Differentiation of the Terrestrial Planets

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.


Hubble Maps Temperature and Water Vapor on an Exoplanet

Hubble Maps Temperature and Water Vapor on an Exoplanet Video in Story

A team of scientists using NASA's Hubble Space Telescope has made the most detailed global map yet of the glow from a planet orbiting another star, revealing secrets of air temperatures and water.


Formation of Close in Super-Earths and Mini-Neptunes

Formation of Close in Super-Earths and Mini-Neptunes

Recent observations by the Kepler space telescope have led to the discovery of more than 4000 exoplanet candidates consisting of many systems with Earth- to Neptune-sized objects that reside well inside the orbit of Mercury, around their respective host stars.



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