Related papers: Rotational Synchronization May Enhance Habitabilit…
Astronomers have discovered that both planets and binaries are abundant throughout the Galaxy. In combination, we know of over 100 planets in binary and higher-order multi-star systems, in both circumbinary and circumstellar configurations.…
The majority of Galactic globular star clusters (GCs) have been reported to contain at least two populations of stars (we use P1 for the primordial and P2 for the chemically-enriched population). Recent observational studies found that…
A new mechanism for the internal heating of ultra-short-period planets is proposed based on the gravitational perturbation by a non-axisymmetric quadrupole moment of their host stars. Such a quadrupole is due to the magnetic flux tubes in…
It has been suggested that tidal interaction is important for shaping the orbital configurations of close orbiting giant planets. The excitation of propagating waves and normal modes (dynamical tide) will be important for estimating time…
Several concepts have been brought forward to determine where terrestrial planets are likely to remain habitable in multi-stellar environments. Isophote-based habitable zones, for instance, rely on insolation geometry to predict…
A number of scenarios for the formation of multiple populations in globular clusters (GCs) predict that second generation (2G) stars form in a compact and dense subsystem embedded in a more extended first-generation (1G) system. If these…
We derive fitting formulae for the quick determination of the existence of S-type and P-type habitable zones in binary systems. Based on previous work, we consider the limits of the climatological habitable zone in binary systems (which…
From the numerous detected planets outside the Solar system, no terrestrial planet comparable to our Earth has been discovered so far. The search for an Exo-Earth is certainly a big challenge which may require the detections of planetary…
A survey of currently known extrasolar planets indicates that close to 20% of their hosting stars are members of binary systems. While the majority of these binaries are wide (i.e., with separations between 250 and 6500 AU), the detection…
We present a comparison between the rotation period distributions of solar-type single stars and primary stars in close binaries (0.1 AU ~< a ~< 5 AU) in the young (150 Myr) open cluster M35 (NGC 2168). We find that the primary stars in the…
An Earth-analog orbiting within the habitable zone of $\alpha$ Centauri B was shown to undergo large variations in its obliquity, or axial tilt, which affects the planetary climate by altering the radiative flux for a given latitude. We…
We have investigated i) the formation of gravitationally bounded pairs of gas-giant planets (which we call "binary planets") from capturing each other through planet-planet dynamical tide during their close encounters and ii) the following…
Our knowledge of planets' orbital dynamics, which was based on Solar System studies, has been challenged by the diversity of exoplanetary systems. Around cool and ultra cool dwarfs, the influence of tides on the orbital and spin evolution…
The existence of extremely wide binaries in the low-inclination component of the Kuiper Belt provides a unique handle on the dynamical history of this population. Some popular frameworks of the formation of the Kuiper Belt suggest that…
Planets around binary stars and those in multiplanet systems may experience resonant eccentricity excitation and disruption due to perturbations from a distant stellar companion. This "evection resonance" occurs when the apsidal precession…
It is shown that several habitability conditions (in fact, at least seven such conditions) appear to be fulfilled automatically by circumbinary planets of main-sequence stars (CBP-MS), whereas on Earth these conditions are fulfilled only by…
We report the detection of Kepler-47, a system consisting of two planets orbiting around an eclipsing pair of stars. The inner and outer planets have radii 3.0 and 4.6 times that of the Earth, respectively. The binary star consists of a…
The Alpha Centauri AB system is an attractive one for radial velocity observations to detect potential exoplanets. The high metallicity of both Alpha Centauri A and B suggest that they could have possessed circumstellar discs capable of…
Exoplanet habitability is traditionally assessed by comparing a planet's semi-major axis to the location of its host star's "habitable zone," the shell around a star for which Earth-like planets can possess liquid surface water. The Kepler…
Although planets have been found orbiting binary systems, whether they can survive binary interactions is debated. While the tightest-orbit binaries should host the most dynamically stable and long-lived circumbinary planetary systems, they…