Related papers: Explaining Planetary-Rotation Periods Using an Ind…
The rotation rate of a star has important implications for the detectability, characterisation and stability of any planets that may be orbiting it. This chapter gives a brief overview of stellar rotation before describing the methods used…
Using a new approach, we have obtained a formula for calculating the rotation period and radius of planets. In the ordinary gravitomagnetism the gravitational spin ($S$) orbit ($L$) coupling, $\vec{L}\cdot\vec{S}\propto L^2$, while our…
We point out an intriguing relation between the masses of the transiting planets and their orbital periods. For the six currently known transiting planets, the data are consistent with a decreasing linear relation. The other known…
We have developed a model for the Earth rotation that gives a good account (data) of the Earth astronomical parameters. These data can be compared with the ones obtained using space-base telescopes. The expansion of the universe has an…
In this chapter, we explore how gravitational interactions drive turbulent flows inside planetary cores and provide an interesting alternative to convection to explain dynamo action and magnetic fields around terrestrial bodies. In the…
The two most common techniques for measuring planetary masses - the radial velocity (RV) and the transit timing variations (TTVs) techniques - have been observed to yield systematically different masses for planets of similar radii.…
Several different factors influence the seasonal cycle of a planet. This study uses a general circulation model and an energy balance model (EBM) to assess the parameters that govern the seasonal cycle. We define two metrics to describe the…
Planet migration is the process by which a planet's orbital radius changes in time. The main agent for causing gas giant planet migration is the gravitational interaction of the young planet with the gaseous disk from which it forms. We…
We suggest the existence of a correlation between the planetary radius and orbital period for planets with radii smaller than 4 R_Earth. Using the Kepler data, we find a correlation coefficient of 0.5120, and suggest that the correlation is…
Earth rotation is one of astronomical phenomena without which it is impossible to think of human life. That is why the investigation on the Earth rotation is very important and it has a long history of study. Invention of quartz clocks in…
Limits and characteristic periods of variations in orbital elements of planets were studied by numerical integration of equations of motion. Interrelations between the characteristic periods of variations in orbital elements of some planets…
After a brief recall of the main impacts of stellar rotation on the structure and the evolution of stars, four topics are addressed: 1) the links between magnetic fields and rotation; 2) the impact of rotation on the age determination of…
We develop a simple model of planetary formation, focusing our attention on those planets with masses less than 10 Earth masses and studying particularly the primordial spin parameters of planets resulting from the accretion of…
Earth-mass planets are expected to have atmospheres and experience thermal tides raised by the host star. These tides transfer energy to the planet that can counter the dissipation from bodily tides. Indeed, even a relatively thin…
Earth rotation is determined by polar motion (PM) and length of day (lod). The excitation sources of PM are torques linked to fluid circulations ("geophysical excitations"), and those of lod to luni-solar tides ("astronomical excitations").…
Recent analyses of Kepler space telescope data reveal that transiting planets with orbital periods shorter than about 2-3 days are generally observed around late-type stars with rotation periods longer than about 5-10 days. We investigate…
Planetary rotation rate is a key parameter in determining atmospheric circulation and hence the spatial pattern of clouds. Since clouds can exert a dominant control on planetary radiation balance, rotation rate could be critical for…
The interiors of many planets consist mostly of fluid layers. When these layers are subject to superadiabatic temperature or compositional gradients, turbulent convection transports heat and momentum. In addition, planets are fast rotators.…
Planets that revolve around a binary pair of stars are known as circumbinary planets. The orbital motion of the stars around their center of mass causes a periodic variation in the total instellation incident upon a circumbinary planet.…
Understanding the distribution of angular momentum during the formation of planetary systems is a key topic in astrophysics. Data from the $\textit{Kepler}$ and $\textit{Gaia}$ missions allow to investigate whether stellar rotation is…