Extrasolar Planets: October 2013

Astronomers have discovered the first Earth-sized planet outside the solar system that has a rocky composition like that of Earth. Kepler-78b whizzes around its host star every 8.5 hours, making it a blazing inferno and not suitable for life as we know it. The results are published in two papers in the journal Nature.

Carbon Worlds May be Waterless

Planets rich in carbon, including so-called diamond planets, may lack oceans, according to NASA-funded theoretical research.

The existence of water in extrasolar planetary systems is of great interest as it constrains the potential for habitable planets and life. Here, we report the identification of a circumstellar disk that resulted from the destruction of a water-rich and rocky, extrasolar minor planet.

We investigate water and deuterated water chemistry in turbulent protoplanetary disks. Chemical rate equations are solved with the diffusion term, mimicking turbulent mixing in vertical direction.

Previous attempts to describe circumbinary habitable zones have been concerned with the spatial extent of the zone, calculated analytically according to the combined radiation field of both stars.

We used Keck adaptive optics observations to identify the first planet discovered by microlensing to lie in or near the habitable zone.

On the exoplanet Kepler 7b, the weather is highly predictable, an international team of scientists has found: On any given day, the exoplanet, which orbits a star nearly 1,000 light-years from Earth, is heavily overcast on one side, while the other side likely enjoys clear, cloudless weather.