Extrasolar planets (exoplanets) are the most intriguing objects in astronomy. Currently, over 4,000 exoplanets have been discovered. Among them, about 100 terrestrial ones are in habitable zones, where planetary surface conditions are theoretically suitable with the presence of liquid water. Practicing advanced equipment, technology and method, more sufficient information will enable us to analyze the habitability of exoplanet more systematically. Given the rapid development of space telescopes, capability of characterizing the extrasolar planetary atmospheres and surfaces will be achieved in near future, offering opportunities for direct observation. Ocean has much lower albedo in comparison with land, thus a terrestrial planet largely covered by oceans can be identified via photometric variability as it spins. Several models for simulating the variability have been discussed in literature, and we establish models of photometric variability for habitable terrestrial planets. In this project, oceans and growth of green plants have emerged. Feasibility of identifying habitable planets and habitable moons will be examined with these more realistic models.
|