Related papers: The Potato Radius: a Lower Minimum Size for Dwarf …
At approximate radii of 200-300 km, asteroids transition from oblong `potato' shapes to spheres. This limit is known as the Potato Radius, and has been proposed as a classification for separating asteroids from dwarf planets. The Potato…
The International Astronomical Union definitions for Planet and Dwarf Planet both require that a body has sufficient mass to overcome rigid body forces and self gravitate into a nearly round shape. However, quantitative standards for…
We have analyzed the effects of rotation on mass-radius relationships for single-layer and two-layer planets having a core and an envelope made of pure materials among iron, perovskite and water in solid phase. The numerical surveys use the…
Planets have maximum radii close to that of Jupiter. Qualitatively, the reason for this maximum size is that, as one adds mass, the force of gravity becomes sufficiently strong to cause the radius to decrease. We show that this effect can…
Condensed planets contract or expand as their temperature changes. With the exception of the effect of phase changes, this phenomenon is generally interpreted as being solely related to the thermal expansivity of the planet's components.…
Satellites around large asteroids are preferentially found among those with the most rapid rotation and elongated shape. The taxonomic statistics are similarly skewed; in total, 13 asteroids larger than 100 km are known to have satellites,…
A tidal radius is a distance from a satellite orbiting in a host potential beyond which its material is stripped by the tidal force. We derive a revised expression for the tidal radius of a rotating satellite which properly takes into…
Existing upper limits on variations in the photospheric radius of the Sun during the solar magnetic activity cycle are at a fractional amplitude of 2x10^{-4}. At that level, the transit duration of a close-in planet around a Sun-like star…
The radius of an exoplanet may be affected by various factors, including irradiation, planet mass and heavy element content. A significant number of transiting exoplanets have now been discovered for which the mass, radius, semi-major axis,…
We calculate an empirical, non-parametric estimate of the shape of the period-marginalized radius distribution of planets with periods less than 150 days using the small yet well-characterized sample of cool ($T_{\rm eff} <4000 $K) dwarf…
It is well known that planets with radii between that of Earth and Neptune have been the most commonly detected to-date. To classify these planets as either terrestrial or gaseous, typically we turn to mass-radius relations and composition…
The radius valley, i.e., a dearth of planets with radii between 1.5 and 2 Earth radii, provides insights into planetary formation and evolution. Using homogenously revised planetary parameters from Kepler 1-minute short cadence light…
Mass and radius are two of the most fundamental properties of an astronomical object. Increasingly, new planet discoveries are being announced with a measurement of one of these terms, but not both. This has led to a growing need to…
The destiny of planetary systems through the late evolution of their host stars is very uncertain. We report a metal-rich gas disk around a moderately hot and young white dwarf. A dynamical model of the double-peaked emission lines…
Masses and radii of transiting brown dwarfs can be measured directly in contrast to isolated field brown dwarfs, whose mass and radius inferences are model dependent. Therefore, transiting brown dwarfs are a testbed for the interior and…
Considering effects of tidal plus centrifugal stress acting on icy-rocks and the tensile strength thereof, icy-rocks being in the density range (1-2.4) g cm-3 which had come into existence as collisional ejecta (debris) in the vicinity of…
Transiting planet surveys like Kepler have provided a wealth of information on the distribution of planetary radii, particularly for the new populations of super-Earth and sub-Neptune sized planets. In order to aid in the physical…
Since white dwarfs are small, the contrast between the thermal emission of an orbiting object and a white dwarf is dramatically enhanced compared to a main sequence host. Furthermore, rocky objects much smaller than the moon have no…
A few studies have reported a significant dearth of exoplanets with Neptune mass and radius with orbital periods below $2$--$4$ d. This cannot be explained by observational biases because many Neptunian planets with longer orbital periods…
We investigated the formation and evolution of satellite systems in a cold, extended circumplanetary disc around a 10 $M_{\rm{Jupiter}}$ gas giant which was formed by gravitational instability at 50\,AU from its star. The disc parameters…