Strong tidal interaction with the central star can circularize the orbits of close-in planets. With the standard tidal quality factor Q of our solar system, estimated circularization times for close-in extrasolar planets are typically shorter than the ages of the host stars. While most extrasolar planets with orbital radii a . 0.1AU indeed have circular orbits, some close-in planets with substa...

Many of the recently discovered extrasolar giant planets move around their stars on highly eccentric orbits, and some with e& 0±7. Systems with planets within or near the habitable zone (HZ) will possibly harbour life on terrestrial-type moons if the seasonal temperature extremes resulting from the large orbital eccentricities of the planets are not too severe. Here we use a three-dimensional g...

Using test particle simulations we examine the structure of the outer Galactic disk as it is perturbed by a satellite in a tight eccentric orbit about the Galaxy. A satellite of mass a few times 109M⊙ can heat the outer Galactic disk, excite spiral structure and a warp and induce streams in the velocity distribution. We examine particle eccentricity versus the change in mean radius between init...

In this chapter, we present analytic calculations of gravitational waves from a particle orbiting a black hole. We first review the Teukolsky formalism for dealing with the gravitational perturbation of a black hole. Then we develop a systematic method to calculate higher order post-Newtonian corrections to the gravitational waves emitted by an orbiting particle. As applications of this method,...

Using test particle simulations we examine the structure of the outer Galactic disk as it is perturbed by a low mass satellite in a tight eccentric orbit about the Galaxy. A low mass satellite of mass a few times 109M⊙ can heat the outer Galactic disk, excite spiral structure and a warp and induce streams in the velocity distribution. We examine particle eccentricity versus the change in mean r...

The semi-analytic theory of tidal shocks proves to be a powerful tool to study tidal interactions of star clusters and satellite galaxies with their massive hosts. New models of the globular cluster evolution employ a combination of analytic estimates, solutions of the FokkerPlanck equation and direct N-body simulations. The models predict large destruction rates for the Galactic globular clust...

Many of the known extrasolar planets are “hot Jupiters,” giant planets with orbital periods of just a few days. We use the observed distribution of hot Jupiters to constrain the location of its inner edge in the mass–period diagram. If we assume a slope corresponding to the classical Roche limit, then we find that the edge corresponds to a separation close to twice the Roche limit, as expected ...

We present direct kinematic evidence for bar streaming motions in two active galaxies with boxy stellar bulges. The Hawaii Imaging Fabry-Perot Interferometer was used on the 3.6 m Canada-FranceHawaii Telescope and the University of Hawaii 2.2 m telescope to derive the two-dimensional velocity Ðeld of the line-emitting gas in the disks of the Sc galaxy NGC 3079 and the Sb galaxy NGC 4388. In con...

We present direct kinematic evidence for bar streaming motions in two active galaxies with boxy stellar bulges. The Hawaii Imaging Fabry-Perot Interferometer was used on the Canada-France-Hawaii 3.6-m telescope and the University of Hawaii 2.2-m telescope to derive the two-dimensional velocity eld of the line-emitting gas in the disks of the Sc galaxy NGC 3079 and the Sb galaxy NGC 4388. In con...

This paper explores the problem of analytically approximating orbital state for a subset orbits in rotating potential with oblateness and ellipticity perturbations. is done by isolating approximate differential equations orbit radius other elements. The conservation Jacobi integral used to make solvable first-order solutions are characterized as small deviations from an unperturbed circular orb...