In this handout image released by NASA, vapor trails follow space shuttle Atlantis as it approaches Runway 15 on the Shuttle Landing Facility at NASA’s Kennedy Space Center at Cape Canaveral, Fla. Thursday, July 21, 2011, for the final time. Atlantis marked the 26th nighttime landing of NASA’s Space Shuttle Program and the 78th landing at Kennedy. It also was the final mission for the shuttle program. (AP Photo/Sandra Joseph and Kevin O’Connell, HO)

Lightning strikes over the Puyehue volcano, over 500 miles south of Santiago, Chile, Monday June 6, 2011. Authorities have evacuated about 3,500 people in the nearby area. The volcano was calm on Monday, two days after raining down ash and forcing thousands to flee, although the cloud of soot it had belched out still darkened skies as far away as Argentina. (AP Photo/Francisco Negroni, AgenciaUno)