Astrophysicist Designs Solar System that Could Hold 60 Earths
Sean Raymond of Bordeaux University has created the ideal stellar system that can hold as many habitable planets as possible without breaking the laws of physics. Using his game, the fantasy star system, he created a solar system that could hold 60 Earth-like planets. Although this system is unlikely to exist in reality, the theories behind it could be helpful for finding solar systems with habitable planets.
The only rule of the game, besides abiding by the laws of physics, is that the fantasy solar system must be potentially stable over billions of years, under the theory that creating an unstable solar system in which the planets eventually collide with the sun is unhelpful for future scientific endeavors.
The program was based on the most recent research on the subject, as well as limited calculations on Raymond's part. Occasionally, he was forced to choose between equally plausible systems, so he simply chose the one he liked best.
Arguably the most important decision was the kind of star that would serve as the system's sun, or host. He chose a red dwarf star, which are smaller and cooler than the Milky Way's Sun. Since it has less mass, it would live longer than our Sun and provide for a habitable zone (an area around a star in which liquid water can exist) that would remain stable over time.
In order to increase the planetary capacity of his solar system, Raymond gave each Earth-sized planet its own potentially habitable moon, and allowed for two planets to orbit the red dwarf star at the same distance, which is possible as long as they are separated by 60 degrees. In our solar system, there aren't any planets that orbit the Sun at the same distance because the space is occupied by asteroids, but there is technically no reason why it couldn't be occupied by another planet.
He then added many Jupiter-like planets to the solar system. Although Jupiter is not habitable itself, it can be surrounded by Earth-like moons. In our solar system, Jupiter's moons, Europa and Enceladus, are some of the most promising candidates for harboring alien life.
Finally, he turned the system into a binary system with two red dwarfs, each with their own sets of Earth pairs, moons, and Jupiters.
Mikko Tuomi, the scientist who discovered the solar system with the highest number of planets on record, found the game to be "thought-provoking," but doubted that the fantasy solar system could exist in reality. "This would be due to the lack of matter at or near the habitable zone in the accretion disk from which planets form," he explains. Raymond himself admits that it would be "extremely fortuitous for nature to produce a system that was so spectacular." But then he qualifies, "Still, each piece of the system is plausible and even expected from simulations of planetary formation."