Pope Francis greets the crowd from his popemobile in downtown Rio de Janeiro. Pope Francis touched down in Rio de Janeiro on Monday, starting his first foreign trip as pontiff and a weeklong series of events expected to attract more than a million people to a gathering of young faithful in Brazil, home to the world's largest Roman Catholic population. (Photo by Ueslei Marcelino/Reuters)

A dog swims as a resident navigates his boat in a neighbourhood flooded by the Purus river, which continues to rise from days of heavy rainfall in the region, in Boca do Acre, Amazonas state March 14, 2015. According the state civil defense, more than 20,000 people have been left homeless along the Purus river, where incessant rains have flooded the area and caused the river to burst their banks. (Photo by Bruno Kelly/Reuters)

Members of the Uniao da Ilha do Governador Samba School perform during the first day of the Special Group Samba Schools parade of Carnival at the Sambadrome in Rio de Janeiro, Brazil, 07 February 2016. (Photo by Luiz Eduardo Perez/EPA)

Brazilians in favor of the impeachment of President Dilma Rousseff demonstrate as the Lower House of Congress voted over her impeachment in Brasilia, Brazil April 17, 2016. The sign reads, “The people want justice. Prison for the corrupt”. (Photo by Adriano Machado/Reuters)

Celebrities including singer Nicole Scherzinger and actor Simon Pegg have been snapped by top photographer Rankin for an Oxfam campaign. All in all, a dozen well-known faces have been captured in various poses to highlight the charity's Lift Lives for Good campaign. The fundraising drive, launched at the start of the year, aims to shine a light on the work done by the charity to help poor people around the world. Photo: Undated handout photo issued by Oxfam of Caroline Flack who took part in a photo shoot with top photographer Rankin for Oxfam's Lift Lives for Good campaign. (Photo by Rankin/PA Wire)

Space shuttle Atlantis launches from pad 39A on July 8, 2011 at the NASA Kennedy Space Center in Cape Canaveral, Florida. The launch of Atlantis, STS-135, is the final flight of the shuttle program, a 12-day mission to the International Space Station. (Photo by Bill Ingalls/NASA via Getty Images)

An inmate (L) tends to a fellow prisoner while performing ear candling during an alternative therapy session as part of the ACUDA programme, at a complex of ten prisons in Porto Velho, Rondonia State, Brazil, August 27, 2015. Ear candling, which involves inserting a hollow cone-shaped device into the ear canal and lighting the exposed end, is believed by practitioners to draw out earwax. According to ACUDA the therapy is beneficial for the inmates' emotional health. (Photo by Nacho Doce/Reuters)

A student of the "Escola de Papai Noel do Brasil" (Brazil's school of Santa Claus) wears his hat before lessons in Rio de Janeiro, Brazil, October 27, 2015. The school, which was founded since 1993, prepare men to represent Santa Claus during the Christmas season. Lessons include singing, physical activity, how to dress and how to care for their beard. (Photo by Pilar Olivares/Reuters)