The Solar System Is Unique
And Some Scientists Don’t Like That Idea
As highlighted in Slashdot, scientists’ research indicates that a solar system like our own develops only under very specific conditions. Deviating from these conditions lead to planets and planetary orbits that are very much different from what we know permits life to form. That is, our solar system is in no way “average”.
Due to the complexity of the developing system, which includes the disk-planet and planet-planet interactions described, the simulations resulted in random systems. Nevertheless, two dominant cases were detected.
In a disk with low mass and high viscosity, the gas in the disk is removed before a planet can form, resulting in a system that has only rocky, icy bodies. At the other end, in a disk with high mass and low viscosity, planets are formed but are pulled towards the center of the system and acquire highly elliptical orbits around the star.
In the intermediate case, planets form but undergo only modest migration towards the star and their orbits don’t become as elliptical. This seems to be the case of the solar system. The simulation showed that this case is realized in a small number of systems, meaning the solar system does not resemble most planetary systems.
This is in agreement with the fact that, although some 200 exo-solar systems have been located, the large majority contain massive, “Jupiter-like” planets whose orbits are wildly elliptical. That is, they come very close to their central star and then swing far outward. Massive bodies orbiting in highly elliptical paths remove the possibility of smaller, presumably undetected bodies having stable, circular orbits. It’s also known that the largest bodies in the solar system, primarily Jupiter and Saturn, serve to “regularize” (and stabilize) the orbits of the smaller bodies like the Earth by virtue of their circular orbits acting to smooth out perturbations.
Copernicus would not amused to discover that we just might be a “special case” after all.