Extra-Planetary Digital Cultures

Extra-solar Planetary Systems

Stability Limits in Extra-solar Planetary Systems

Two types of stability boundaries exist for any planetary system consisting of one star and two planets. Lagrange stability requires that the planets remain bound to the star, conserves the ordering of the distance from the star, and limits the variations of orbital elements like semi-major axis and eccentricity. Hill stability only requires that the ordering of the planets remain constant; the...

Scale-relativity and quantization of extra-solar planetary systems

We show in the present letter that the planetary companions recently discovered around nearby stars agree with the predictions made four years ago in the framework of the theory of scale relativity (Nottale, 1993). In the simplest case, we expect their periods to be "quantized" as Tn = 2πGMn3/w 0 3 ~– 3.25 (M/M ) n3 days. In this formula, which corresponds to the peak of probability distributio...

Extra-Solar Planetary Systems in the VLT Era

Radial Velocity surveys have revealed 63 exoplanets (M sin i < 10MJup) and 6 multi-planetary systems (status on the 4th of April 2001). Distributions of orbital elements already have been given some constraints on the formation of planetary systems. Derived from recent high resolution spectroscopy studies, the impressive role of the stellar metallicity on the giant planet formation has been rev...

Terrestrial Planet Formation in Extra-Solar Planetary Systems

Terrestrial planets form in a series of dynamical steps from the solid component of circumstellar disks. First, km-sized planetesimals form likely via a combination of sticky collisions, turbulent concentration of solids, and gravitational collapse from micron-sized dust grains in the thin disk midplane. Second, planetesimals coalesce to form Moonto Mars-sized protoplanets, also called “planeta...