Seminar

TRAPPIST-1 is a system of seven sub-Earth-mass to Earth-mass planets orbiting in close-in orbits around a very low-mass star. The planets in this system are near resonance with period ratios 24:15:9:6:4:3:2, making this system the longest resonant chain system to be discovered. As the planets are very close to their star, they are subjected to tidal forces which can move them, putting the system’s stability in question and prompting us to consider the importance of tides for this system. In our quest to understand the formation of this system, we will look at how to assemble the planets into their current configuration via migration and whether the resonances formed will become unstable, as pointed by recent studies. From this, we can derive some constraints for the migration parameters that are able to reproduce the TRAPPIST-1 system. Given the observed periods of the planets, if there are two-body resonances in the system, we can also constrain the eccentricities of the planets.