相关论文: The surface sensitivity of rubble-pile asteroids d…
Asteroids are frequently colliding with small projectiles. Although each individual small collision is not very important, their cumulative effect can substantially change topography and also the overall shape of an asteroid. We run…
A statistical analysis of brightness variability of asteroids reveals how their shapes evolve from elongated to rough spheroidal forms, presumably driven by impact-related phenomena. Based on the Sloan Digital Sky Survey Moving Object…
We calculate the evolution of planets undergoing a strong tidal encounter using smoothed particle hydrodynamics (SPH), for a range of periastron separations. We find that outside the Roche limit, the evolution of the planet is…
We have developed a theoretical description of how of an asteroid's polarization-phase curve will be affected by the removal of the dust from the surface due to a size-dependent phenomenon such as radiation pressure-driven escape of…
Most asteroids are somewhat elongated and have non-zero lightcurve amplitudes. Such asteroids can be detected in large-scale sky surveys even if their mean magnitudes are fainter than the stated sensitivity limits. We explore the detection…
Until recently, most asteroids were thought to be solid bodies whose shapes were determined largely by collisions with other asteroids. It now seems that many asteroids are little more than rubble piles, held together by self-gravity; this…
The orbital evolution of particles released from the surface of a rubble-pile body by Earth's tides during flyby within the Roche limit is studied. Test particles initially placed on the surface leave the surface and escape the parent body.…
Conditions for regolith landslides to occur on spinning, gravitating spheroidal asteroids and their aftermath are studied. These conditions are developed by application of classical granular mechanics stability analysis to the asteroid…
The architecture of many exoplanetary systems is different from the solar system, with exoplanets being in close orbits around their host stars and having orbital periods of only a few days. We can expect interactions between the star and…
When studying transiting exoplanets it is common to assume a spherical planet shape. However short rotational periods can cause a planet to bulge at its equator, as is the case with Saturn whose equatorial radius is almost 10% larger than…
We aim to understand how landslides affect the shape and rotational motion of small rubble planetary bodies. We limit ourselves to axisymmetric global landslides, and take the primordial shape of the body to also be axisymmetric. The…
We have investigated the obliquity evolution of terrestrial planets in habitable zones (at ~ 1AU) in extrasolar planetary systems, due to tidal interactions with their satellite and host star with wide varieties of satellite-to-planet mass…
Eccentricity is an important orbital parameter. Understanding its effect on planetary climate and habitability is critical for us to search for a habitable world beyond our solar system. The orbital configurations of M-dwarf planets are…
We investigate two possible effects of the tidal field induced by a spherical cluster on its elliptical galaxy members: the modification of the ellipticity of a spherical galaxy and the isophotal alignment in the cluster radial direction of…
Large ground- and space-based telescopes will be able to observe Earth-like planets in the near future. We explore how different planetary surfaces can strongly influence the climate, atmospheric composition, and remotely detectable spectra…
Many asteroids that make close encounters with terrestrial planets are in a binary configuration. Here we calculate the relevant encounter timescales and investigate the effects of encounters on a binary's mutual orbit. We use a combination…
We quantify the systematic impact of the non-spherical shape of transiting planets and brown dwarfs, due to tidal forces and rotation, on the observed transit depth. Such a departure from sphericity leads to a bias in the derivation of the…
We analyze the long-term tidal evolution of a single-planet system through the use of numerical simulations and averaged equations giving the variations of semi-major axis and eccentricity of the relative orbit. For different types of…
Transiting planets are generally close enough to their host stars that tides may govern their orbital and thermal evolution of these planets. We present calculations of the tidal evolution of recently discovered transiting planets and…
The obliquities of planet-hosting stars are clues about the formation of planetary systems. Previous observations led to the hypothesis that for close-in giant planets, spin-orbit alignment is enforced by tidal interactions. Here, we…