Mexico's Smoking MountainHalfway across the globe from Fuji, Popocatepetl-one of the world's tallest and most dangerous active volcanoes-stands just 60 kilometers (37 miles) southeast of Mexico City.Although the volcano (whose name mans "smoking mountain") has erupted many times over the centuries, scientists believe its last great eruption occurred around 820 A.D.In recent years, however, EI Popo, as Mexicans call the mountain, has been threatening to explode once more; in December 2000, almost 26,000 people were evacuated when EI Popo started to send out ash and smoke.As with all active volcanoes, the question is not if it will erupt again (an eruption is inevitable); the question is when it will happen.