相关论文: Most 1.6 Earth-Radius Planets are not Rocky

Approximately half of the extrasolar planets (exoplanets) with radii less than four Earth radii are in orbits with short periods. Despite their sheer abundance, the compositions of such planets are largely unknown. The available evidence…

Super-Earths and mini-Neptunes exhibit great diversity in their compositional and orbital properties. Their bulk densities span a large range, from those dense enough to be purely rocky to those needing a substantial contribution from…

Solar system planets move on almost circular orbits. In strong contrast, many massive gas giant exoplanets travel on highly elliptical orbits, whereas the shape of the orbits of smaller, more terrestrial, exoplanets remained largely…

We present newly derived stellar parameters and the detailed abundances of 19 elements of seven stars with small planets discovered by NASA's Kepler Mission. Each star save one has at least one planet with a radius <= 1.6 R_Earth,…

NASA's Kepler Mission uses transit photometry to determine the frequency of earth-size planets in or near the habitable zone of Sun-like stars. The mission reached a milestone toward meeting that goal: the discovery of its first rocky…

The Kepler mission revealed a class of planets known as ''super-puffs,'' with masses only a few times larger than Earth's but radii larger than Neptune, giving them very low mean densities. All three of the known planets orbiting the young…

Space-based transit missions such as Kepler and TESS have demonstrated that planets are ubiquitous. However, the success of these missions heavily depends on ground-based radial velocity (RV) surveys, which combined with transit photometry…

The ongoing High Accuracy Radial velocity Planet Search (HARPS) has found that 30-50% of GK dwarfs in the solar neighborhood host planets with sub-Neptune masses in orbits of P < 50 days. At first glance, this overall occurrence rate seems…

Short-period super-Earths and mini-Neptunes encircle more than $\sim50\%$ of Sun-like stars and are relatively amenable to direct observational characterization. Despite this, environments in which these planets accrete are difficult to…

We extract densities and eccentricities of 139 sub-Jovian planets by analyzing transit time variations (TTVs) obtained by the Kepler mission through Quarter 12. We partially circumvent the degeneracies that plague TTV inversion with the…

Kepler has found hundreds of Neptune-size (2-6 R_Earth) planet candidates within 0.5 AU of their stars. The nature of the vast majority of these planets is not known because their masses have not been measured. Using theoretical models of…

We investigated the underlying architecture of planetary systems by deriving the distribution of planet multiplicity (number of planets) and the distribution of orbital inclinations based on the sample of planet candidates discovered by the…

In the Solar system the planets' compositions vary with orbital distance, with rocky planets in close orbits and lower-density gas giants in wider orbits. The detection of close-in giant planets around other stars was the first clue that…

Discoveries from the prime Kepler mission demonstrated that small planets (< 3 Earth-radii) are common outcomes of planet formation. While Kepler detected many such planets, all but a handful orbit faint, distant stars and are not amenable…

The Kepler Mission has discovered thousands of exoplanets and revolutionized our understanding of their population. This large, homogeneous catalog of discoveries has enabled rigorous studies of the occurrence rate of exoplanets and…

We report the detection of three transiting planets around a Sunlike star, which we designate Kepler-18. The transit signals were detected in photometric data from the Kepler satellite, and were confirmed to arise from planets using a…

The majority of the transiting planets discovered by the Kepler mission (called super-Earths here, includes the so-called 'sub-Neptunes') orbit close to their stars. As such, photoevaporation of their hydrogen envelopes etch sharp features…

The search for Earth-like planets around Sun-like stars and the evaluation of their occurrence rate is a major topic of research for the exoplanetary community. Two key characteristics in defining a planet as 'Earth-like' are having a…

Characterizing the dependence of the orbital architectures and formation environments on the eccentricity distribution of planets is vital for understanding planet formation. In this work, we perform statistical eccentricity studies of…

The determination of exoplanet properties and occurrence rates using Kepler data critically depends on our knowledge of the fundamental properties (such as temperature, radius and mass) of the observed stars. We present revised stellar…