关键词: 太阳系外的行星, 凌星, 类地行星, 宜居带, 外星生命

Abstract:

Just 39 lightyears from the sun, 7 earth-sized planets are orbiting a star whose mass is only about eight percent of that of the Sun. The orbits of these planets are only about as large as those of Jupiter’s Galilean moons, and the periods of orbiting around the star are only one and a half days to about twelve days. They are likely to be rocky planets, which may have liquid waters and atmospheres and have habitable conditions in at least some areas on their surfaces. More such planets are being found, which will be the preferred targets of scientific observations after the operation of the James Webb Space Telescope that will be launched. At that time, it is possible to draw the conclusions on whether these planets have atmospheres and what compositions the atmospheres made up of if they do exist. It is quite possible that we can find out life signatures on one or a few extrasolar planets.

Key words: exoplanet, transit, terrestrial planet, habitable zone, extraterrestrial life