London 2012 Opening Ceremony - The Olympic rings are seen during a pyrotechnics display at the pre-show before the opening ceremony of the London 2012 Olympic Games at the Olympic Stadium July REUTERS/Suzanne Plunkett
Christina Loukas competes in the women's Springboard Diving semi-final Christina Loukas of the United States competes in the women's Springboard Diving semi-final on Day 8 of the London 2012 Olympic Games.
Layers at the Base of Mount Sharp. A chapter of the layered geological history of Mars is laid bare in this postcard from NASA's Curiosity rover. The image shows the base of Mount Sharp, the rover's eventual science destination.