Residents observe a police officer take up position during an operation at the Mare slums complex in Rio de Janeiro March 25, 2014. The federal troops have taken control of security operations in Mare slums complex to help quell a surge in violent crime following attacks by drug traffickers on police posts in three slums on the north side of the city, government officials said. (Photo by Ricardo Moraes/Reuters)

“Only the most intrepid urban explorers cross the tattered ruins of the old Iron Curtain to endure the excessive bureaucracy, military paranoia and freezing winds of the East to hunt for the ghosts of an empire. Rebecca Litchfield is one who couldn't resist the haunting allure of the ruins of the Soviet Union”. – Yahoo News. Photo: Hungary, MAV 424 Steam Train. (Photo by Rebecca Bathory)

Walkers cross the river Waalbrug during the first day of the 98th annual four-days walking event, the “Vierdaagse” in Nijmegen, Netherlands, July 15, 2014. The “Nijmeegse Vierdaagse” is an annual public four-day field march which is held since 1909 in the third week of July. (Photo by Erik van 't Wout/EPA)

Photographer Brian Finke spent nearly two years traversing the friendly skies, following the life of flight attendants in the air and on the ground, from Delta and Hawaiian Air, to Hooters Air, Southwest, Air France, British Airways, Air Asia, and dozens more. His images of flight attendants waving, applying makeup and deboarding plans while smiling appear as if they were ripped from an advertisement in a glossy magazine. Here: Tiger Airways, Singapore, 2006. (Photo by Brian Finke/The Washington Post)

A girl pulls her sister in a discarded basket in the Rashidabad neighborhood of Peshawar, Pakistan October 18, 2015. (Photo by Khuram Parvez/Reuters)

People in costume take photos during a Halloween event on October 31, 2015 in Lan Kwai Fong, Central District, Hong Kong. Halloween, a named taken from 'All Hallows' Even' falls on the day before All Saints' Day on November 1, a holiday when Christians remember their deceased loved ones. (Photo by Jerome Favre/Getty Images)

Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

A giant sculpture of a seven-month-old baby by artist Marc Quinn entitled “Planet” contrasts against the stately grandeur of Chatsworth House and the Derbyshire countryside on 4 September, 2008, Chatsworth, England. The bronze sculpture painted white is part of the Beyond Limits exhibition of modern and contemporary sculpture displayed in the gardens of Chatsworth by Sotherby's. More than 20 works will be on display from 9 September to 2 November 2008. In past years acclaimed artists Damien Hirst, Antony Gormley, Salvador Dali and Henry Moore have had work exhibited. (Photo by Christopher Furlong/Getty Images)