The Real Science of Avatar

On Earth: China's Huangshan
Like the Hallelujahs, the peculiarly jutting granite peaks of Huangshan in Eastern China's Anhui Province are often shrouded in clouds. In this case, art followed reality, which then followed art: Officials in a separate area of China, in Hunan province's Zhangjiajie, renamed one of their craggy peaks the "Avatar Hallelujah Mountain" to appeal to tourists.

• In Honor of Earth Day: The Earth from Above