Boys walk home for lunch from school in the village of Kogelo, west of Kenya's capital Nairobi, July 16, 2015. U.S. President Barack Obama visits Kenya and Ethiopia later this month. His ancestral home of Kogelo is home to Sarah Hussein Obama, his step-grandmother. The Kenyan village, burial place of Obama's father, features an open-pit goldmine, a pork butcher's, a school named after their most famous son and outdoor market stalls. Villagers get around by motorbike taxi or on foot while a donkey-cart transports water. Children, some of them named Obama in honour of the President, walk to and from school together. (Photo by Thomas Mukoya/Reuters)

A girl clings to her mother as they travel on a flooded street amid heavy rainfall in Shenzhen, Guangdong province, China, July 24, 2015. Approximately a million people have been affected by severe downpours in several Chinese provinces, causing collapsed houses, decimating crops as well as blocking highways, reported Xinhua News Agency. (Photo by Reuters/Stringer)

The NASA Extreme Environment Mission Operations (NEEMO) 21 mission began on July 21 as an international crew of aquanauts splashed down to the undersea Aquarius Reef Base, located 62 feet below the surface of the Atlantic Ocean in the Florida Keys National Marine Sanctuary. The NEEMO 21 crew will perform research both inside and outside the habitat during a 16-day simulated space mission. During simulated spacewalks carried out underwater, they will evaluate tools and mission operation techniques that could be used in future space missions, including journeys to Mars. (Photo by Karl Shreeves/NASA)

Photographer and editor with Reuters for 22 years, Andrew Winning has died of brain cancer at the age of 49. Here: Elite special police run for cover after gunfire was heard from inside the Japanese ambassador's residence in Lima, Peru, January 27, 1997. At the moment the shots were fired, police were parading past the residence in a show of force, and helicopters were flying above. Earlier, several armored personnel carriers rolled past the compound. Tupac Amaru rebels had seized the diplomatic compound December 17 and held 72 hostages. (Photo by Andrew Winning/Reuters)

A woman looks out of the window of a house as saris, traditional clothing worn by women, are hanged out to dry in Lalitpur, Nepal on April 17, 2019. (Photo by Navesh Chitrakar/Reuters)

Girls dressed in Soviet WWII uniforms of traffic control officers as Russian President Vladiimir Putin lays a wreath in the Hall of Military Glory of the Mamayev Kurgan memorial complex commemorating the Battle of Stalingrad to mark the 75th anniversary of the victory in the battle in Volgograd, Russia on February 2, 2018. The battle between Nazi troops and the Soviet Army was a major pivotal moment in the Great Patriotic War and World War II. (Photo by Mikhail Metzel/TASS via Getty Images)

The photography of Art Wolfe covers the globe, capturing landscapes, wildlife, and cultures from every continent; here he talks through a selection of his favourite images. Art Wolfe is an American photographer and conservationist. His photographs have been noted by environmental advocacy groups for their “stunning” visual impact. Here: Snowy owlets (Bubo scandiacus), Arctic National Wildlife Refuge, Alaska, USA. (Photo by Art Wolfe/Art Wolfe Stock)

Pinky Ghelani and Suzzy Wokabi watch a TV broadcast of Britain's Prince Harry and Meghan Markle's royal wedding at the Windsor golf and country club in Nairobi, Kenya May 19, 2018. (Photo by Thomas Mukoya/Reuters)