Related papers: Possible Internal Structures and Compositions of P…
Massive and water-rich planets should be ubiquitous in the universe. Many of those worlds are expected to be subject to important irradiation from their host star, and display supercritical water layers surrounded by extended steam…
We present the analysis of emission lines in high-resolution optical spectra of the planet-host star Proxima Centauri (Proxima) classified as a M5.5V\@. We carry out the detailed analysis of observed spectra to get a better understanding of…
To aid in the physical interpretation of planetary radii constrained through observations of transiting planets, or eventually direct detections, we compute model radii of pure hydrogen-helium, water, rock, and iron planets, along with…
Recent studies have shown that alpha Centauri B might be, from an observational point of view, an ideal candidate for the detection of an Earth-like planet in or near its habitable zone (0.5-0.9AU). We study here if such habitable planets…
We examine the feasibility of detecting auroral emission from the potentially habitable exoplanet Proxima Centauri b. Detection of aurorae would yield an independent confirmation of the planet's existence, constrain the presence and…
The origin of Mercury still remains poorly understood compared to the other rocky planets of the Solar System. One of the most relevant constraints that any formation model has to fulfill refers to its internal structure, with a predominant…
Planets with masses between Earth and Neptune often have radii that imply the presence of volatiles, suggesting that water may be abundant in their interiors. However, directly observing the precise water mass fraction and water…
We describe the current state of knowledge about Mercury's interior structure. We review the available observational constraints, including mass, size, density, gravity field, spin state, composition, and tidal response. These data enable…
Here it is shown how to find the interior structure of a variety of rock-and-iron planetary bodies by using the rock density and some aspects of the core density as known for the Earth and using a convection principle for the iron-rich…
The mass of CoRoT-7b, the first transiting superearth exoplanet, is still a subject of debate. A wide range of masses have been reported in the literature ranging from as high as 8 M_Earth to as low as 2.3 M_Earth. Although most mass…
Mercury's core mass fraction (CMF) is ~0.7, more than double that of the other rocky planets in the solar system, which have CMFs of ~0.3. The origin of Mercury's large, iron-rich core remains unknown. Adding to this mystery, an elusive…
The recent detection of Earth-sized planets in the habitable zone of Proxima Centauri, Trappist-1 and many other nearby M-type stars has led to speculations, whether liquid water and life actually exist on these planets. To a large extent,…
Planetary formation models predict the existence of massive terrestrial planets and experiments are now being designed that should succeed in discovering them and measuring their masses and radii. We calculate internal structures of planets…
Seeing oceans, continents, quasi-static weather, and other surface features on exoplanets may allow us to detect and characterize life outside the solar system. The Proxima b planet resides within the stellar habitable zone allowing for…
The detection and characterisation of Earth-like planets with Doppler signals of the order of 1 m/s currently represent one of the greatest challenge for extrasolar-planet hunters. As results for such findings are often controversial, it is…
The planet GJ 1214b is the second known super-Earth with a measured mass and radius. Orbiting a quiet M-star, it receives considerably less mass-loss driving X-ray and UV radiation than CoRoT-7b, so that the interior may be quite dissimilar…
We apply Monte Carlo projection to the radial velocity data set that Anglada Escude et al. (2016) use for the discovery of Proxima b. They find an upper limit to the orbital eccentricity of 0.35. To investigate the eccentricity issue…
Using the most recent kinematic and radial velocity data in the literature, we calculate the binding energy of Proxima Centauri relative to the center of mass of the Alpha Centauri system. When we adopt the centroids of the observed data,…
Giant exoplanets on wide orbits have been directly imaged around young stars. If the thermal background in the mid-infrared can be mitigated, then exoplanets with lower masses can also be imaged. Here we present a ground-based mid-infrared…
The high density of the close-in extrasolar planet HD149026b suggests the presence of a huge core in the planet, which challenges planet formation theory. We first derive constraints on the amount of heavy elements and hydrogen/helium…