#SHOWSTARS LADA FULL#

In this work, we focus on the study of the effect of stellar encounters, characteristic of different Galactic environments, on debris disks (planets, cometary nuclei, etc.) to determine the dynamical stability and habitability potential of planets around stars. Nevertheless, any single close stellar encounter can change disc orbital dynamics dramatically, in such a way that its effect might not be erased by other typical processes like planetary interactions (one example is the Kuiper belt). The other processes affect dynamics at much larger timescales and may be more important in regions where stellar density is smaller (solar neighborhood or young stellar clusters) and the number of encounters is less probable.

This type of encounter can readily and rapidly change orbital parameters of planets and minor bodies (JimГ©nez-Torres and Pichardo, 2008). The most violent of these processes are stellar interactions. Astrobiology 13, 491вЂ“509.Д ebris disks are extremely fragile entities that can be dynamically perturbed by a number of processes, for example, planet-planet interactions (Batygin et al., 2011), interactions between giant planets of similar size (Raymond et al., 2011, 2012), secular perturbations by giant planets (Mustill and Wyatt, 2009), migrating planets (Walsh et al., 2011), the presence of a stellar companion (Kaib et al., 2011 Paardekooper et al., 2012 ThГ©bault, 2012), or gravitational interactions with other stars (JimГ©nez-Torres and Pichardo, 2008 Lestrade et al., 2011). Key Words: Stellar interactions-Galactic habitable zone-Oort cloud. We calculated the probability of whether Oort clouds exist in these Galactic environments. We also considered the conditions in globular clusters, the Galactic nucleus, and the Galactic bulge-bar.

We specifically studied the case of Messier 67, one of the oldest open clusters known, and show the effect of this environment on debris disks. For older clusters the results may not be the same. We found that in open clusters habitable zones are not readily disrupted this is true if they evaporate in less than 10 8 yr. We studied the effect of stellar encounters on planetary orbits within the habitable zones of stars in more crowded stellar environments, such as stellar clusters.

#SHOWSTARS LADA FULL#

Current knowledge of the full phase space of stars in the solar neighborhood, however, is rather poor thus we cannot rule out the existence of a star that is more likely to approach than those for which we have complete kinematic information. We found occurrence of a disturbing impact to the solar planetary disk within the next 8 Myr to be highly unlikely perturbations to the Oort cloud seem unlikely as well.

With this information from literature, we simulated flyby encounters for several Galactic regions, numerically calculating stellar trajectories as well as orbits for particles in disks our aim was to understand the effect of typical stellar flybys on planetary (debris) disks in the Milky Way Galaxy.ДЇor the solar neighborhood, we examined nearby stars with known distance, proper motions, and radial velocities. Every Galactic environment is characterized by a stellar density and a velocity dispersion.

Showstars lada