Fredagskollokvium: The plurality of worlds

I will discuss the importance of discovering planets orbiting stars that do not look like the Sun, with a special focus on planets orbiting ultra-cool dwarfs.
We recently discovered the TRAPPIST-1 planetary system during the initial stage a dedicated survey for planet orbiting stars at the bottom of the Main-Sequence. I will describe that discovery of multiple Earth-like planets, and present updates on our knowledge of the system, for instance on the orbital period of the outermost planet.
Following this, I will show considerations about the occurrence rate of planets orbiting very low mass stars, and how the TRAPPIST-1 planets compare to planets orbiting Sun-like stars, giving us clues about their formation.