author={Artie P. Hatzes and Heike Rauer},
  journal={The Astrophysical Journal Letters},
  • A. Hatzes, H. Rauer
  • Published 16 June 2015
  • Geology, Physics
  • The Astrophysical Journal Letters
We present the mass–density relationship (log M − log ρ) for objects with masses ranging from planets (M ≈ 0.01 MJup) to stars (M > 0.08 M⊙). This relationship shows three distinct regions separated by a change in slope in the log M − log ρ plane. In particular, objects with masses in the range 0.3 MJup–60 MJup follow a tight linear relationship with no distinguishing feature to separate the low-mass end (giant planets) from the high-mass end (brown dwarfs). We propose a new definition of giant… 

Two empirical regimes of the planetary mass-radius relation

Today, with the large number of detected exoplanets and improved measurements, we can reach the next step of planetary characterization. Classifying different populations of planets is not only

Evidence of an Upper Bound on the Masses of Planets and Its Implications for Giant Planet Formation

Celestial bodies with a mass of have been found orbiting nearby stars. It is unknown whether these objects formed like gas-giant planets through core accretion or like stars through gravitational

K2-106, a system containing a metal-rich planet and a planet of lower density

Planets in the mass range from 2 to 15 M_Earth are very diverse. Some of them have low densities, while others are very dense. By measuring the masses and radii, the mean densities, structure, and

The Origin of the Heavy-element Content Trend in Giant Planets via Core Accretion

We explore the origin of the trend of heavy elements in observed massive exoplanets. Coupling of better measurements of the mass (Mp) and radius of exoplanets with planet structure models enables

A Sanity Check for Planets around Evolved Stars

We present the radius–period plot for exoplanet candidates around giant stars. The diagram contains two distinct regions. While planets of giants with radii smaller than 21 R ⊙ exhibit a wide range

Planet formation around M dwarfs via disc instability

Context. Around 30 per cent of the observed exoplanets that orbit M dwarf stars are gas giants that are more massive than Jupiter. These planets are prime candidates for formation by disc

Impact of binary stars on planet statistics – I. Planet occurrence rates and trends with stellar mass

  • M. MoeK. Kratter
  • Geology, Physics
    Monthly Notices of the Royal Astronomical Society
  • 2021
Close binaries suppress the formation of circumstellar (S-type) planets and therefore significantly bias the inferred planet occurrence rates and statistical trends. After compiling various radial

Absolute densities in exoplanetary systems: photodynamical modelling of Kepler-138

In favourable conditions, the density of transiting planets in multiple systems can be determined from photometry data alone. Dynamical information can be extracted from light curves, providing

The TOI-763 system: sub-Neptunes orbiting a Sun-like star

We report the discovery of a planetary system orbiting TOI-763(aka CD-39 7945), a V = 10.2, high proper motion G-type dwarf star that was photometrically monitored by the TESS space mission in

Minimum Orbital Periods of H-rich Bodies

In this work we derive the minimum allowed orbital periods of H-rich bodies ranging in mass from Saturn’s mass to 1 M ⊙, emphasizing gas giants and brown dwarfs (BDs) over the range 0.0003–0.074 M ⊙.




We report the results of a study of the intermediate- and high-mass stars in the young, rich star-forming complex IC 1805, based on a combination of optical, near-infrared, and mid-infrared

Discovery of two young brown dwarfs in an eclipsing binary system

This work reports the discovery of a brown-dwarf eclipsing binary system, in the Orion Nebula star-forming region, from which direct measurements of mass and radius establish both objects as brown dwarfs, and finds that the less-massive brown dwarf is the hotter of the pair.

Mass-radius relation of low and very low-mass stars revisited with the VLTI

We measured the radii of 7 low and very low-mass stars using long baseline interferometry with the VLTI interferometer and its VINCI and AMBER near-infrared recombiners. We use these new data,

An orbital period of 0.94 days for the hot-Jupiter planet WASP-18b

Either WASP-18 is in a rare, exceptionally short-lived state, or the tidal dissipation in this system (and possibly other hot-Jupiter systems) must be much weaker than in the Solar System.

The theory of brown dwarfs and extrasolar giant planets

Straddling the traditional realms of the planets and the stars, objects below the edge of the main sequence have such unique properties, and are being discovered in such quantities, that one can

Exoplanetary Geophysics: An Emerging Discipline

A planet-sized transiting star around OGLE-TR-122. Accurate mass and radius near the hydrogen-burning limit

We report the discovery and characterisation of OGLE-TR-122b, the smallest main-sequence star to date with a direct radius determination. OGLE-TR-122b transits around its solar-type primary every

Accurate masses and radii of normal stars: modern results and applications

This article presents and discusses a critical compilation of accurate, fundamental determinations of stellar masses and radii. We have identified 95 detached binary systems containing 190 stars (94

The PLATO 2.0 mission

PLATO 2.0 has recently been selected for ESA’s M3 launch opportunity (2022/24). Providing accurate key planet parameters (radius, mass, density and age) in statistical numbers, it addresses

The Formation of Massive Stars

Abstract There has been considerable progress in our understanding of how massive stars form but still much confusion as to why they form. Recent work from several sources has shown that the