Evolution of galaxy habitability

Tides and the evolution of planetary habitability.

Tides raised on a planet by the gravity of its host star can reduce the planet's orbital semi-major axis and eccentricity. This effect is only relevant for planets orbiting very close to their host stars. The habitable zones of low-mass stars are also close in, and tides can alter the orbits of planets in these locations. We calculate the tidal evolution of hypothetical terrestrial planets arou...

A model of habitability within the Milky Way galaxy.

We present a model of the galactic habitable zone (GHZ), described in terms of the spatial and temporal dimensions of the Galaxy that may favor the development of complex life. The Milky Way galaxy was modeled using a computational approach by populating stars and their planetary systems on an individual basis by employing Monte Carlo methods. We began with well-established properties of the di...

Galaxy Evolution

The Evolution of Galaxy

52 Scientific American December 1998 T royal Ferret of Comets was busy tracking his prey. On the night of April 15, 1779, Charles Messier watched from his Paris observatory as the Comet of 1779 slowly passed between the Virgo and Coma Berenices constellations on its long journey through the solar system. Messier’s renown in comet spotting had inspired the furry moniker from King Louis XV, but o...

Galaxy Formation and Evolution