On The Origin of Free Floating Planets: Planet Ejection During Terrestrial Planet Formation

During the formation of terrestrial planets, many planetesimals and planetary embryos may be ejected from the formation region. As the dynamics of these objects are affected by the perturbation of giant planets, questions have been raised as to whether any of these bodies reach interstellar space where they can become free-floating planets. We present results of 7000 integrations of objects scattered out of the formation region during the simulations of the formation of terrestrial planets in our solar system. We show that many of these bodies may potentially leave the solar system and form a population of free-floating planets. Our integrations show that the average mass of these bodies is 0.4 Mars-masses implying that small free-floating planets may be common.