People walk past a man preaching along a train track in Ikeja district in Nigeria's commercial capital Lagos April 12, 2016. (Photo by Akintunde Akinleye/Reuters)

A seagull flies through a rainbow near the Savannah River and the open spillway at Thurmond Dam in Clarks Hill, SC, Monday, January 4, 2016. (Photo by Michael Holahan/Augusta Chronicle via AP Photo)

A Virgin Atlantic passenger plane flies in the sky with the moon seen in the background, in London, Britain January 19, 2016. (Photo by Toby Melville/Reuters)

A homeless girl asks for alms outside a coffee shop in Mumbai, India, June 24, 2016. (Photo by Danish Siddiqui/Reuters)

Smoke plumes rise from Mount Etna, one of the most active volcanoes in the world in Sicily, Italy on June 28, 2016. (Photo by Etna Walk/Rex Feature/Shutterstock)

Children attend a war safety awareness class conducted by civil defence members, in the rebel-controlled area of Maaret al-Numan town in Idlib province, Syria May 14, 2016. (Photo by Khalil Ashawi/Reuters)

A general view of atmosphere at the annual VOLT Festival in Sopron, 208 kms west of Budapest, Hungary on August 16, 2016. (Photo by Mudra László/Rockstar Photographers)

A member of the Revolutionary Armed Forces of Colombia (FARC) pose for a picture at a camp in the Colombian mountains on February 2005. (Photo by Frank Piasecki Poulsen)