Habitability and Stability of Orbits for Earth-Like Planets in the Extrasolar System 47 UMa

We investigate wether Earth-type habitable planets can in principle exist in the planetary system of 47 UMa. The system 47 UMa consists of two Jupiter-size planets beyond the outer edge of the stellar habitable zone, and thus resembles our own Solar system most closely compared to all exosolar planetary systems discovered so far. We estimate if Earth-type habitable planets planets around 47 UMa are in principle possible by investigating if a distinct set of conditions is warrented. In the event of successful formation and orbital stability, two subjects of intense research, we find that Earth-type habitable planets around 47 UMa are in principle possible! The likelihood of those planets is increased if assumed that 47 UMa is relatively young (younger than approximately 6 Gyr) and has a relatively small stellar luminosity as permitted by the observational range of those parameters. We show that the likelihood to find a habitable Earth-like planet on a stable orbit around 47 UMa critically depends on the percentage of the planetary land/ocean coverage. The likelihood is significantly increased for planets with a very high percentage of ocean surface (“water worlds”).