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Extrasolar Planets: August 2016


The NASA Kepler mission has discovered thousands of new planetary candidates, many of which have been confirmed through follow-up observations. A primary goal of the mission is to determine the occurrance rate of terrestrial-size planets within the Habitable Zone (HZ) of their host stars. Here we provide a list of HZ exoplanet candidates from the Kepler Data Release 24 Q1-Q17 data vetting process.

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 studies typically use ad hoc initial distributions based on theoretical and numerical studies.

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 ultimately at finding a planet similar to Earth\-the Earth's twin, and answering the question of potential exo-habitability.

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.

We analyze the evolution of the potentially habitable planet Proxima Centauri b to identify environmental factors that affect its long-term habitability. We consider physical processes acting on size scales ranging between the galactic scale, the scale of the stellar system, and the scale of the planet's core.

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.

A new generation of dedicated Doppler spectrographs will attempt to detect low-mass exoplanets around mid-late M stars at near infrared (NIR) wavelengths, where those stars are brightest and have the most Doppler information content.

The search for habitable, alien worlds needs to make room for a second "Goldilocks," according to a Yale University researcher.

We reconsider the commonly held assumption that warm debris disks are tracers of terrestrial planet formation. The high occurrence rate inferred for Earth-mass planets around mature solar-type stars based on exoplanet surveys (roughly 20%) stands in stark contrast to the low incidence rate (less than 2-3%) of warm dusty debris around solar-type stars during the expected epoch of terrestrial planet assembly (roughly 10 Myr).

The habitability of planets in binary star systems depends not only on the radiation environment created by the two stars, but also on the perturbations to planetary orbits and rotation produced by the gravitational field of the binary and neighbouring planets.

The distant planet GJ 1132b intrigued astronomers when it was discovered last year. Located just 39 light-years from Earth, it might have an atmosphere despite being baked to a temperature of around 450 degrees Fahrenheit. But would that atmosphere be thick and soupy or thin and wispy? New research suggests the latter is much more likely.

Short-period Earth to Neptune size exoplanets (super-Earths) with voluminous gas envelopes seem to be very common. These gas atmospheres are thought to have originated from the protoplanetary disk in which the planets were embedded during their first few Myr.

We classified the reddest (r-J> 2.2) stars observed by the NASA Kepler mission into main sequence dwarf or evolved giant stars and determined the properties of 4216 M dwarfs based on a comparison of available photometry with that of nearby calibrator stars, as well as available proper motions and spectra.

O2 and O3 have been long considered the most robust individual biosignature gases in a planetary atmosphere, yet multiple mechanisms that may produce them in the absence of life have been described.

We investigate 3D atmosphere dynamics for tidally locked terrestrial planets with an Earth-like atmosphere and irradiation for different rotation periods (Prot=1100 days) and planet sizes (RP=12REarth) with unprecedented fine detail.

Binary systems with similar components are ideal laboratories which allow several physical processes to be tested, such as the possible chemical pattern imprinted by the planet formation process.

Looking for another Earth? An international team of researchers has pinpointed which of the more than 4,000 exoplanets discovered by NASA's Kepler mission are most likely to be similar to our rocky home.