Chechen Interior Minister Ruslan Alkhanov greets participants of the military parade to mark the Victory Day in Grozny, Russia, May 9, 2015. Russia marks the 70th anniversary of the end of World War Two in Europe on Saturday with a military parade, showcasing new military hardware at a time when relations with the West have hit lows not seen since the Cold War. (Photo by Reuters/Host Photo Agency/RIA Novosti)

A Mexican wearing a period costume re-enacts the battle of Puebla, in the Penon de los Banos neighbourhood of Mexico City, Mexico May 5, 2016. The battle marked the defeat of French forces by Mexican troops and local Indians in the central state of Puebla in 1862. During the re-enactment, participants fired homemade shotguns loaded with gunpowder and hundreds of men dressed as Indian peasants fought mock battles against others dressed as French invaders. (Photo by Henry Romero/Reuters)

A dog trainer works with a previously abandoned dog at a police centre in Saltillo, Mexico March 4, 2016. Stray dogs are adopted by the police from a municipal anti-rabies centre and then trained to help the police patrol the streets, and search for drugs, explosives and weapons. (Photo by Daniel Becerril/Reuters)

Nelson Hernandez flashes the victory sign as he shows off one of the voodoo dolls that he is selling at El Viejo Lazaro Botanica to try and help the Miami Heat fans root their team on against the Dallas Mavericks in the NBA finals on June 9, 2011 in Miami, Florida. The dolls made from cotton come in white or black and they are all the same size. The user of the doll must have the name of the player attached to the doll, which is filled with cotton, herbs, sticks and a special powder. (Photo by Joe Raedle/Getty Images)

“NASA's Mars rover Opportunity just celebrated its ninth anniversary on Mars – a mission that was originally meant to last just 90 days...” – The Atlantic. Photo: NASA's rover Opportunity visits Victoria Crater, viewed from orbit by the High Resolution Imaging Science Experiment on NASA's Mars Reconnaissance Orbiter in october of 2006. Opportunity is a small dot on the crater's lip, at top right. Opportunity first reached the crater's rim on September 27, 2006. (Photo by NASA/JPL-Caltech/University of Arizona via The Atlantic)

Metropolitan Transit Authority (MTA) Police Officer Keith Flood trains with his K-9 partner Doc, a German Shepherd, inside the “warehouse room” at the new MTA Police Department Canine Training Center in Stormville, New York, U.S., June 6, 2016. (Photo by Mike Segar/Reuters)

People take pictures of the Tribute in Light while it is illuminated next to the Statue of Liberty (C), One World Trade Center and the Empire State Building during events marking the 14th anniversary of the 9/11 attacks on the World Trade Center in New York September 11, 2015. (Photo by Eduardo Munoz/Reuters)

Comedian Jeffrey Ross (C) arrives at Comedy Central's Roast of Charlie Sheen held at Sony Studios on September 10, 2011 in Los Angeles, California. (Photo by Christopher Polk/Getty Images)