DR. RAVI KUMAR KOPPARAPU

Identifying terrestrial planets in the habitable zones (HZs) of other stars is one of the primary goals of ongoing exoplanet surveys and proposed space-based flagship missions. In this talk, I will discuss about our recent results on the new estimates of HZs around Main-sequence stars for terrestrial mass planets. According to our new model, a conservative estimate of the inner (moist greenhouse) and outer (maximum greenhouse) HZ limits for our Solar System are at 0.99 AU and 1.67 AU, respectively, suggesting that the present Earth lies near the inner edge. Our model does not include the radiative effects of clouds; thus, the actual HZ boundaries may be broader than our estimates. We have developed an interactive online HZ calculator to estimate the HZ limits around different stars (http://www3.geosc.psu.edu/~ruk15/planets/). I will also briefly discuss about our current efforts regarding 3-D HZ calculations. Applying the new HZ limits to extrasolar planetary systems from NASA's "Kepler" mission data, we find that potentially habitable planets around M-dwarf stars are more common than previously reported, and a conservative estimate of the occurrence rate of Earth-size planets around G & K stars may be ~ 25%.