Topic
Planetary body
About: Planetary body is a research topic. Over the lifetime, 251 publications have been published within this topic receiving 5548 citations.
Papers published on a yearly basis
Papers
TL;DR: In this paper, the authors examine the uncertainties in current planetary models and quantify their impact on the planet cooling histories and massradius relationships, including the differences between the various equations of state used to characterize the heavy material thermodynamic properties, the distribution of heavy elements within planetary interiors, their chemical composition, and their thermal contribution to the planet evolution.
Abstract: Aims. We examine the uncertainties in current planetary models and quantify their impact on the planet cooling histories and massradius relationships. Methods. These uncertainties include (i) the differences between the various equations of state used to characterize the heavy material thermodynamical properties, (ii) the distribution of heavy elements within planetary interiors, (iii) their chemical composition, and (iv) their thermal contribution to the planet evolution. Our models, which include a gaseous H/He envelope, are compared with models of solid, gasless Earth-like planets in order to examine the impact of a gaseous envelope on the cooling and the resulting radius. Results. We find that, for a fraction of heavy material larger than 20% of the planet mass, the distribution of the heavy elements in the planet’s interior substantially affects the evolution and thus the radius at a given age. For planets with large core mass fractions (>50%), such as the Neptune-mass transiting planet GJ 436b, the contribution of the gravitational and thermal energy from the core to the planet cooling history is not negligible, yielding a ∼10% effect on the radius after 1 Gyr. We show that the present mass and radius determinations of the massive planet Hat-P-2b require at least 200 M⊕ of heavy material in the interior, at the edge of what is currently predicted by the core-accretion model for planet formation. As an alternative avenue for massive planet formation, we suggest that this planet, and similarly HD 17156b, may have formed from collisions between one or several other massive planets. This would explain these planets unusually high density and high eccentricity. We show that if planets as massive as ∼25 MJ can form, as predicted by improved core-accretion models, deuterium is able to burn in the H/He layers above the core, even for core masses as high as ∼100 M⊕. Such a result highlights the confusion provided by a definition of a planet based on the deuterium-burning limit. Conclusions. We provide extensive grids of planetary evolution models from 10 M⊕ to 10 MJup, with various fractions of heavy elements. These models provide a reference for analyzing the transit discoveries expected from the CoRoT and Kepler missions and for inferring the internal composition of these objects.
434 citations
TL;DR: In this article, atmospheric pollution by various elements heavier than helium has been used to infer that a comparable fraction of the white dwarf descendants of such main-sequence stars are orbited by planetary systems, and for plausible planetary system configurations, this total mass is likely to be at least equal to that of the Sun's asteroid belt.
Abstract: Infrared studies have revealed debris likely related to planet formation in orbit around ~30% of youthful, intermediate mass, main-sequence stars. We present evidence, based on atmospheric pollution by various elements heavier than helium, that a comparable fraction of the white dwarf descendants of such main-sequence stars are orbited by planetary systems. These systems have survived, at least in part, through all stages of stellar evolution that precede the white dwarf. During the time interval (~200 million years) that a typical polluted white dwarf in our sample has been cooling it has accreted from its planetary system the mass of one of the largest asteroids in our solar system (e.g., Vesta or Ceres). Usually, this accreted mass will be only a fraction of the total mass of rocky material that orbits these white dwarfs; for plausible planetary system configurations we estimate that this total mass is likely to be at least equal to that of the Sun's asteroid belt, and perhaps much larger. We report abundances of a suite of eight elements detected in the little studied star G241-6 that we find to be among the most heavily polluted of all moderately bright white dwarfs.
329 citations
TL;DR: In this paper, the authors provide a summary of knowledge about the Moon geologic processes and describe major scientific advancements of the last decade that are mainly related to the most recent lunar missions such as Galileo, Clementine, and Lunar Prospector.
Abstract: Beyond the Earth, the Moon is the only planetary body for which we have samples from known locations. The analysis of these samples gives us “ground-truth” for numerous remote sensing studies of the physical and chemical properties of the Moon and they are invaluable for our fundamental understanding of lunar origin and evolution. Prior to the return of the Apollo 11 samples, the Moon was thought by many to be a primitive undifferentiated body (e.g., Urey 1966), a concept shattered by the data returned from the Apollo and Luna missions. Ever since, new data have helped to address some of our questions, but of course, they also produced new questions. In this chapter we provide a summary of knowledge about lunar geologic processes and we describe major scientific advancements of the last decade that are mainly related to the most recent lunar missions such as Galileo, Clementine, and Lunar Prospector.
### 1.1. The Moon in the planetary context
Compared to terrestrial planets, the Moon is unique in terms of its bulk density, its size, and its origin (Fig. 1.1a–c⇓), all of which have profound effects on its thermal evolution and the formation of a secondary crust (Fig. 1.1d⇓). Numerous planetary scientists considered the Moon as an endmember among the planetary bodies in our solar system because its lithosphere has been relatively cool, rigid, and intact throughout most of geological time (a “one-plate” planet), and its surface has not been affected by plate recycling, an atmosphere, water, or life. Therefore the Moon recorded and preserved evidence for geologic processes that were active over the last 4–4.5 b.y. and offers us the unique opportunity to look back into geologic times for which evidence on Earth has long been erased (Fig. 1.1c,d⇓). Impact cratering, an exterior process, is considered the most important surface process on the Moon. Internal …
234 citations
TL;DR: In this article, the authors show that mass loss from a central star during post main sequence evolution can sweep planetesimals into interior mean motion resonances with a single giant planet.
Abstract: It has long been suspected that metal polluted white dwarfs (types DAZ, DBZ, and DZ) and white dwarfs with dusty disks possess planetary systems, but a specific physical mechanism by which planetesimals are perturbed close to a white dwarf has not yet been fully posited. In this paper we demonstrate that mass loss from a central star during post main sequence evolution can sweep planetesimals into interior mean motion resonances with a single giant planet. These planetesimals are slowly removed through chaotic excursions of eccentricity that in time create radial orbits capable of tidally disrupting the planetesimal. Numerical N-body simulations of the Solar System show that a sufficient number of planetesimals are perturbed to explain white dwarfs with both dust and metal pollution, provided other white dwarfs have more massive relic asteroid belts. Our scenario requires only one Jupiter-sized planet and a sufficient number of asteroids near its 2:1 interior mean motion resonance. Finally, we show that once a planetesimal is perturbed into a tidal crossing orbit, it will become disrupted after the first pass of the white dwarf, where a highly eccentric stream of debris forms the main reservoir for dust producing collisions. These simulations, in concert with observations of white dwarfs, place interesting limits on the frequency of planetary systems around main sequence stars, the frequency of planetesimal belts, and the probability that dust may obscure future terrestrial planet finding missions.
210 citations
TL;DR: In this article, the authors analyzed the transit times of the TrES-1 system given in Charbonneau et al. and found no convincing evidence for a second planet from those data and constrain the mass that a perturbing planet could have as a function of the semi-major axis ratio of the two planets.
Abstract: The presence of a second planet in a known, transiting-planet system will cause the time between transits to vary. These variations can be used to constrain the orbital elements and mass of the perturbing planet. We analyse the set of transit times of the TrES-1 system given in Charbonneau et al. We find no convincing evidence for a second planet in the TrES-1 system from those data. By further analysis, we constrain the mass that a perturbing planet could have as a function of the semi-major axis ratio of the two planets and the eccentricity of the perturbing planet. Near low-order, mean-motion resonances (within ∼1 per cent fractional deviation), we find that a secondary planet must generally have a mass comparable to or less than the mass of the Earth ‐ showing that these data are the first to have sensitivity to subEarth-mass planets. We compare the sensitivity of this technique to the mass of the perturbing planet with future, high-precision radial velocity measurements. Ke yw ords: eclipses ‐ stars: individual: GSC 02652 − 01324 ‐ planetary systems.
132 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 2 |
| 2020 | 7 |
| 2019 | 8 |
| 2018 | 6 |
| 2017 | 15 |
| 2016 | 10 |