468_extrasolar_planet_Gliese581c_surface
The extrasolar planet Gliese 581c is slightly larger than earth and orbits in the habitable zone of its star. The "Twilight Zone" near the boundary between day and night might afford a temperate climate. The sun would be fixed in place near the horizon, however, and plants might tend to grow in waves, struggling for sunlight, with fallow regions in the shadowlands between crests of forest vegetation. Digital artwork copyright 2008 Don Dixon / cosmographica.com