Hundreds of Nigerians celebrate at an intersection in the flashpoint northern city of Kaduna on March 31, 2015 the victory of main opposition All Progressives Congress (APC) presidential candidate Mohammadu Buhari. (Photo by Nichole Sobecki/AFP Photo)

Private Harold L. Langhofer edges into the ball-turret, March 9, 1943. Curled in this position, he can turn the turret so that it fires in any direction. The turret can also be swung around so that the hatch opens into the plane, and the gunner can crawl into it while the Flying Fortress is in motion. (Photo by AP Photo)

Fireworks explode above Singapore's financial skyline at dusk as part of celebrations for the nation's 50th year of independence, Sunday, August 9, 2015, in Singapore. Singapore declared independence on August 9, 1965. (Photo by Wong Maye-E/AP Photo)

People are reflected on a soap bubble lying on a road during the evening in New Delhi, India, June 23, 2015. (Photo by Anindito Mukherjee/Reuters)

A bonnet macaque sits on consecrated idols of snakes during the Nag Panchami festival inside a temple on the outskirts of Bengaluru, India, August 19, 2015. (Photo by Abhishek N. Chinnappa/Reuters)

Laborers work on scaffolding near a full-scale replica of the Sphinx at an unfinished movie and animation tourism theme park, in Chuzhou, Anhui province, March 27, 2015. (Photo by Reuters/China Daily)

Two F-15E Strike Eagles wait to receive fuel from a KC-135R Stratotanker during exercise Red Flag 15-1 on their way to Nellis Air Force Base, Nev., Jauary 23, 2015. The F-15s are assigned to the 4th Fighter Wing. U.S. (Photo by Airman 1st Class Aaron J. Jenne/Reuters)

Daring Captain Kevin Oprey is seen standing beneath the soaring hull of Cunard’s flagship Queen Mary 2.