Extrasolar Planets


Searching for Earth-mass planets around α Centauri

Searching for Earth-mass planets around α Centauri

This work is part of an ongoing project which aims to detect terrestrial planets in our neighbouring star system α Centauri using the Doppler method.


Astronomers come up dry in search for water on exoplanets

Astronomers come up dry in search for water on exoplanets

A team of astronomers has made the most precise measurements yet of water vapour in the atmospheres of Jupiter-like planets beyond our Solar System and found them to be much drier worlds than expected.


Atmospheric dynamics of terrestrial exoplanets over a wide range of orbital and atmospheric parameters

Atmospheric dynamics of terrestrial exoplanets over a wide range of orbital and atmospheric parameters

The recent discoveries of terrestrial exoplanets and super Earths extending over a broad range of orbital and physical parameters suggests that these planets will span a wide range of climatic regimes.


Direct Imaging of Exoplanets in the Habitable Zone with Adaptive Optics

Direct Imaging of Exoplanets in the Habitable Zone with Adaptive Optics

One of the primary goals of exoplanet science is to find and characterize habitable planets, and direct imaging will play a key role in this effort.


Revision of Earth-sized Kepler Planet Candidate Properties with High Resolution Imaging by Hubble Space Telescope

Revision of Earth-sized Kepler Planet Candidate Properties with High Resolution Imaging by Hubble Space Telescope

We present the results of our Hubble Space Telescope program and describe how our image analysis methods were used to re-evaluate the habitability of some of the most interesting Kepler planet candidates.


Stellar Activity Masquerading as Planets in the Habitable Zone of the M dwarf Gliese 581

Stellar Activity Masquerading as Planets in the Habitable Zone of the M dwarf Gliese 581

The M dwarf Gliese 581 is believed to host four planets, including one (GJ 581d) near the habitable zone that could possibly support liquid water on its surface if it is a rocky planet.


Effects of Refraction on Transit Transmission Spectroscopy: Application to Earth-like Exoplanets

Effects of Refraction on Transit Transmission Spectroscopy: Application to Earth-like Exoplanets

We quantify the effects of refraction in transit transmission spectroscopy on spectral absorption features and on temporal variations that could be used to obtain altitude-dependent spectra for planets orbiting stars of different stellar types.


Water Vapor in the Spectrum of the Extrasolar Planet HD 189733b

Water Vapor in the Spectrum of the Extrasolar Planet HD 189733b

We report near-infrared spectroscopy of the gas giant planet HD 189733b in transit. We used the Hubble Space Telescope Wide Field Camera 3 (HST WFC3) with its G141 grism covering 1.1 um to 1.7 um and spatially scanned the image across the detector at 2\arcsecs−1.


Friction from Tides Could Make Extrasolar Planets Habitable

Friction from Tides Could Make Extrasolar Planets Habitable

As anybody who has started a campfire by rubbing sticks knows, friction generates heat. Now, computer modeling by NASA scientists shows that friction could be the key to survival for some distant Earth-sized planets traveling in dangerous orbits.


Hubble High Resolution Imaging of Kepler Small and Cool Exoplanet Host Stars

Hubble High Resolution Imaging of Kepler Small and Cool Exoplanet Host Stars

High resolution imaging is an important tool for follow-up study of exoplanet candidates found via transit detection with the Kepler Mission. We discuss here HST imaging with the WFC3 of 23 stars that host particularly interesting Kepler planet candidates based on their small size and cool equilibrium temperature estimates.


Detection of Earth-mass Planets Around Active Stars: The Mass of Kepler-78b

Detection of Earth-mass Planets Around Active Stars: The Mass of Kepler-78b

Kepler-78b is a transiting Earth-mass planet in an 8.5 hr orbit discovered by the Kepler Space Mission. We performed an analysis of the published radial velocity measurements for Kepler-78 in order to derive a refined measurement for the planet mass.


Newly Spotted Frozen World Orbits in a Binary Star System

Newly Spotted Frozen World Orbits in a Binary Star System

A newly discovered planet in a binary star system located 3,000 light-years from Earth is expanding astronomers' notions of where Earth-like--and even potentially habitable--planets can form, and how to find them.


Two Goldilocks Planets That Might Support Life are Proven False

Two Goldilocks Planets That Might Support Life are Proven False Video in Story

Mysteries about controversial signals coming from a dwarf star considered to be a prime target in the search for extraterrestrial life now have been solved in research led by scientists at Penn State University.


A Stellar-mass-dependent Drop in Planet Occurrence Rates

A Stellar-mass-dependent Drop in Planet Occurrence Rates

The Kepler Space Telescope has discovered a large number of planets up to one year periods and down to terrestrial sizes.


A Catalog of Nearby Cool Host-Stars for Habitable Exoplanets and Life

A Catalog of Nearby Cool Host-Stars for Habitable Exoplanets and Life

We present an all-sky catalog of 2970 nearby (d≲50 pc), bright ( J<9 ) M- or late K-type dwarf stars, 86% of which have been confirmed by spectroscopy.


GJ 832c: A Super-Earth in the Habitable Zone

GJ 832c: A Super-Earth in the Habitable Zone

We report the detection of GJ 832c, a super-Earth orbiting near the inner edge of the habitable zone of GJ 832, an M dwarf previously known to host a Jupiter analog in a nearly-circular 9.4-year orbit.


Transit and Radial Velocity Survey Efficiency Comparison for a Habitable Zone Earth

Transit and Radial Velocity Survey Efficiency Comparison for a Habitable Zone Earth

Transit and radial velocity searches are two techniques for identifying nearby extrasolar planets to Earth that transit bright stars.


Chemical Modeling of Exoplanet Atmospheres

Chemical Modeling of Exoplanet Atmospheres

The past twenty years have revealed the diversity of planets that exist in the Universe. It turned out that most of exoplanets are different from the planets of our Solar System and thus, everything about them needs to be explored.


Detecting Industrial Pollution in the Atmospheres of Earth-like Exoplanets

Detecting Industrial Pollution in the Atmospheres of Earth-like Exoplanets

Detecting biomarkers, such as molecular oxygen, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life.


Exoplanet Population Inference and the Abundance of Earth Analogs from Noisy, Incomplete Catalogs

Exoplanet Population Inference and the Abundance of Earth Analogs from Noisy, Incomplete Catalogs

No true extrasolar Earth analog is known. Hundreds of planets have been found around Sun-like stars that are either Earth-sized but on shorter periods, or else on year-long orbits but somewhat larger.



Top stories from July.