相关论文: A Pilot Search for Evidence of Extrasolar Earth-an…
Extrasolar planet host stars have been found to be enriched in key planet-building elements. These enrichments have the potential to drastically alter the composition of material available for terrestrial planet formation. Here we report on…
Extrasolar planetary host stars are enriched in key planet-building elements. These enrichments have the potential to drastically alter the building blocks available for terrestrial planet formation. Here we report on the combination of…
A persistent question in exoplanet demographics is whether exoplanetary systems form from similar compositional building blocks to our own. Polluted white dwarf stars offer a unique way to address this question as they provide measurements…
Earth's tectonic processes regulate the formation of continental crust, control its unique deep water and carbon cycles, and are vital to its surface habitability. A major driver of steady-state plate tectonics on Earth is the sinking of…
To first order, the Earth as well as other rocky planets in the Solar System and rocky exoplanets orbiting other stars, are refractory pieces of the stellar nebula out of which they formed. To estimate the chemical composition of rocky…
Prior studies have hypothesized that some polluted white dwarfs record continent-like granitic crust--which is abundant on Earth and perhaps uniquely indicative of plate tectonics. But these inferences derive from only a few elements, none…
The abundances of elements in the Earth and the terrestrial planets provide the initial conditions for life and clues as to the history and formation of the Solar System. We follow the pioneering work of Bond et al. (2010) and combine…
The relationship between stars and planets provides important information for understanding the interior composition, mineralogy, and overall classification of small planets (R $\lesssim$ 3.5R$_{\oplus}$). Since stars and planets are formed…
Planetary systems that orbit white dwarf stars can be studied via spectroscopic observations of the stars themselves. Numerous white dwarfs are seen to have accreted mostly rocky minor planets, the remnants of which are present in the…
Plate tectonics is a geophysical process currently unique to Earth, has an important role in regulating the Earth's climate, and may be better understood by identifying rocky planets outside our solar system with tectonic activity. The key…
We'll examine plate tectonics on Earth -- its features and forces -- and examine some concepts that may allow astronomers to ask useful questions regarding numeric models that putatively predict tectonic activity. But exo-planetologists…
Context. The crust composition of rocky exoplanets with a substantial atmosphere can not be observed directly. However, recent developments start to allow the observation and characterisation of their atmospheres. Aims. We aim to establish…
The search for extrasolar Earth-like planets is underway. Over 100 extrasolar giant planets are known to orbit nearby sun-like stars, including several in multiple-planet systems. These planetary systems are stepping stones for the search…
Tidal disruption and subsequent accretion of planetesimals by white dwarfs can reveal the elemental abundances of rocky bodies in exoplanetary systems. Those abundances provide information on the composition of the nebula from which the…
No terrestrial planet formation simulation completed to date has considered the detailed chemical composition of the planets produced. While many have considered possible water contents and late veneer compositions, none have examined the…
We report Keck High Resolution Echelle Spectrometer data and model atmosphere analysis of two helium-dominated white dwarfs, PG1225-079 and HS2253+8023, whose heavy pollutions most likely derive from the accretion of terrestrial-type…
In the last few years astronomical surveys have expanded the reach of planetary science into the realm of small and dense extrasolar worlds. These share a number of characteristics with the terrestrial and icy planetary objects of the Solar…
The recent discovery of super-Earths (masses less or equal to 10 earth-masses) has initiated a discussion about conditions for habitable worlds. Among these is the mode of convection, which influences a planet's thermal evolution and…
Oxygen fugacity is a measure of rock oxidation that influences planetary structure and evolution. Most rocky bodies in the Solar System formed at oxygen fugacities approximately five orders of magnitude higher than a hydrogen-rich gas of…
The field of extrasolar planets has rapidly expanded to include the detection of planets with masses smaller than that of Uranus. Many of these are expected to have little or no hydrogen and helium gas and we might find Earth analogs among…