相关论文: Apsidal Alignment in Upsilon Andromedae

The boundaries of the Uranian epsilon, alpha, and beta rings can be fitted by Keplerian ellipses. The pair of ellipses that outline a given ring share a common line of apsides. Apse alignment is surprising because the quadrupole moment of…

We have made a likelihood statistical analysis of the angular correlations in the {\it COBE}-DMR two-year sky maps by Monte Carlo simulation of the temperature fluctuations. We assume an open universe and consider as primordial power…

Polarimetry is a novel tool to detect and characterize exoplanets and their atmospheres. Polarized scattered light from the non-transiting hot Jupiter $\upsilon$~And~b is measured to further constrain its orbit, mass, density, and…

We show that in a system of two planets initially in nearly circular orbits, an impulse perturbation that imparts a finite eccentricity to one planet's orbit causes the other planet's orbit to become eccentric as well, and also naturally…

(Abridged) The solar system gas giant planets are oblate due to their rapid rotation. A measurement of the planet's projected oblateness would constrain the planet's rotational period. Planets that are synchronously rotating with their…

The results of the numerical investigations of the evolution of orbits of trans-Neptunian bodies at the 2 : 3 resonance with Neptune are presented. The gravitational influence of the four giant planets was taken into account. For identical…

Narrow planetary rings are eccentric and inclined. Particles within a given ring must therefore share the same pericenter and node. We solve for the three-dimensional geometries and mass distributions that enable the Uranian Alpha and Beta…

The star upsilon Andromeda is orbited by three known planets, the innermost of which has an orbital period of 4.617 days and a mass at least 0.69 that of Jupiter. This planet is close enough to its host star that the radiation it absorbs…

By using the most recently published Doppler tomography measurements and accurate theoretical modeling of the oblateness-driven orbital precessions, we tightly constrain some of the physical and orbital parameters of the planetary system…

We present a study of the Rayleigh-Taylor unstable regime of accretion onto rotating magnetized stars in a set of high grid resolution three-dimensional (3D) magnetohydrodynamic (MHD) simulations performed in low-viscosity discs. We find…

Since exoplanets were detected using the radial velocity method, they have revealed a diverse distribution of orbital configurations. Amongst these are planets in highly eccentric orbits (e > 0.5). Most of these systems consist of a single…

We integrate the orbital solutions of the planets orbiting 55 Cnc. In the simulations, we find that not only three resonant arguments $\theta_{1}=\lambda_{1}-3\lambda_{2}+2\tilde\omega_{1}$,…

The dynamical interactions of planetary systems may be a clue to their formation histories. Therefore, the distribution of these interactions provides important constraints on models of planet formation. We focus on each system's apsidal…

One possible diagnostic of planet formation, orbital migration, and tidal evolution is the angle psi between a planet's orbital axis and the spin axis of its parent star. In general, psi cannot be measured, but for transiting planets one…

Recent observation of microlensing technique reveals two giant planets at 2.3 AU and 4.6 AU around the star OGLE-06-109L. The eccentricity of the outer planet (ec) is estimated to be 0.11(+0.17,-0.04), comparable to that of Saturn…

Since the discovery of the first exoplanet orbiting a main-sequence star, astronomers have inferred the orbital properties of planets using stellar radial velocity (RV) measurements. For a star orbited by a single planet, the stellar orbit…

A widely considered characteristic of extra-solar planetary systems has been a seeming tendency for major axes of adjacent orbits to librate in stable configurations. Based on a new catalog of extra-solar planets (Butler et al. 2006) and…

With $n$-body simulations we investigate the stability of tilted circumbinary planetary systems consisting of two nonzero mass planets. The planets are initially in circular orbits that are coplanar to each other, as would be expected if…

We present a spectroscopic study of the eclipsing binary system AS Camelopardalis, the first such study based on phase-resolved CCD echelle spectra. Via a spectral disentangling analysis we measure the minimum masses of the stars to be M_A…

With the help of the Laplace-Lagrange solution of the secular perturbation theory in a double-planet system, we study the occurrence and the stability of apsidal secular resonance between the two planets. The explicit criteria to predict…