Related papers: Planets, Planetary Nebulae, and Intermediate Lumin…
Planetary satellites are an integral part of the heirarchy of planetary systems. Here we make two predictions concerning their formation. First, primordial satellites, which have an array of distinguishing characteristics, form only around…
The evolution of a giant planet within the stellar envelope of a main-sequence star is investigated as a possible mechanism for enhancing the stellar metallicities of the parent stars of extrasolar planetary systems. Three-dimensional…
At least 10-15% of nearby sun-like stars have known Jupiter-mass planets. In contrast, very few planets are found in mature open and globular clusters such as the Hyades and 47 Tuc. We explore here the possibility that this dichotomy is due…
Giant planets acquire gas, ices and rocks during the early formation stages of planetary systems and thus inform us on the formation process itself. Proceeding from inside out, examining the connections between the deep interiors and the…
The architecture of exoplanetary systems is often different from the solar system, with some exoplanets being in close orbits around their host stars and having orbital periods of only a few days. In analogy to interactions between stars in…
Planetary nebulae retain the signature of the nucleosynthesis and mixing events that occurred during the previous AGB phase. Observational signatures complement observations of AGB and post-AGB stars and their binary companions. The…
The morphology of planetary nebulae emerging from the common envelope phase of binary star evolution is investigated. Using initial conditions based on the numerical results of hydrodynamical simulations of the common envelope phase it is…
One well-tested method in science is to separate the object of interest from its surroundings and look at it in isolation. The advantage is that unimportant information is removed and the true properties of the object are seen more clearly.…
I study some effects of aspherical mass loss during the last stages of the asymptotic giant branch (AGB) on the appearance of proto planetary nebulae (PNs) and young PNs. The aspherical mass loss can be small scale inhomogeneities, and/or…
Despite the recent discoveries of planets orbiting stars at all evolutionary stages, the evolution of planetary systems remains poorly understood. Studying planetary systems around red giant branch stars can reveal how main sequence…
The discovery of now about 20 extrasolar planets orbiting solar-type stars with properties quite different from those in our Solar System has raised many questions about the formation and evolution of planets. The tidal interaction between…
The present dynamical configuration of planets in binary star systems may not reflect their formation process since the binary orbit may have changed in the past after the planet formation process was completed. An observed binary system…
Planet--Planet scattering is an efficient and robust dynamical mechanism for producing eccentric exoplanets. Coupled to tidal interactions with the central star, it can also explain close--in giant planets on circularized and potentially…
We explore the evolution of a giant planet that interacts with a circumbinary disc that orbits a misaligned binary by means of analytic models and hydrodynamical simulations. Planet-disc interactions lead to mutual tilt oscillations between…
Intermediate mass stars and stellar remnants often host planets, and these dynamical systems evolve because of mass loss and tides. This paper considers the combined action of stellar mass loss and tidal dissipation on planetary orbits in…
The solar system's dynamical state can be explained by an orbital instability among the giant planets. A recent model has proposed that the giant planet instability happened during terrestrial planet formation. This scenario has been shown…
As stars which have planetary systems evolve along the red giant branch and expand, they interact with the close planets. The planets deposit angular momentum and energy into the red giant stars' envelopes, both of which are likely to…
We conduct numerical simulations of axisymmetrical jets expanding into a spherical AGB slow wind. The three-dimensional flow is simulated with an axially symmetric numerical code. We concentrate on jets that are active for a relatively…
From wispy gas giants on the verge of disruption to tiny rocky bodies already falling apart, short-period exoplanets pose a severe puzzle to theories of planet formation and orbital evolution. By far most of the planets known beyond the…
Changes in planetary obliquity, or axial tilt, influence the climates on Earth-like planets. In the solar system, the Earth's obliquity is stabilized due to interactions with our moon and the resulting {small amplitude variations…