24 hours in pictures

Helmand, Afghanistan: A US marine advances under fire through a poppy field towards a Taliban position during a patrol with Afghan army soldiers
Photograph: Mauricio Lima/AFP

Tucson, US: A supporter holds up a cowboy hat at a rally where Sarah Palin campaigned to support John McCain in his Senate re-election bid
Photograph: Darren Hauck/Getty

New Delhi, India: A rickshaw driver takes a nap in the afternoon heat in the Chandni Chowk neighbourhood
Photograph: Kevin Frayer/AP

New York, US: A neighbouring view of construction at the World Trade Centre site
Photograph: Mario Tama/Getty

Singapore: People sit by candlelight in a city park during Earth Hour
Photograph: Pablo Sanchez/Reuters

Sydney, Australia: Composite picture showing the Harbour Bridge with lights on and off for Earth Hour
Photograph: Greg Wood/AFP

Portsmouth, England: The skeleton of a dog, discovered in a cabin of the Tudor warship Mary Rose, on display among the many relics from the wreck of 1545
Photograph: Ian Nicholson/PA

Port-au-Prince, Haiti: A woman waits for a bus as night falls
Photograph: Jorge Saenz/AP

California, US: The first group walks up the first fairway after mist delayed the second round of the Kia Classic at the La Costa course
Photograph: Stephen Dunn/Getty

Sirte, Libya: Camel riders holding flags of Arab countries gather at Sirte to welcome leaders for the Arab League summit
Photograph: Nasser Nasser/AP

Nabi Saleh, West Bank: Palestinian women watch as Israeli border police take position during clashes with Palestinian stone-throwers
Photograph: Abed Omar Qusini/Reuters

London, UK: A British Airways plane lands at Heathrow as cabin crew embark on a four-day strike
Photograph: Dan Kitwood/Getty

Guatemala City, Guatemala: Students of the San Carlos public university wearing orange hoods participate in the annual Huelga de Dolores parade, which commemorates the students' strike of 1898
Photograph: Rodrigo Abd/AP