Russian soldiers dressed in Red Army World War II uniforms attend a rehearsal for the Nov. 7 parade in the Red Square with Spassky Tower in the background, in Moscow, Russia, Friday, November 6, 2015. The parade marks the 74th anniversary of a November 7 parade on Red Square when soldiers went directly to the front during World War II. For decades Nov. 7 was a holiday celebrating the 1917 Bolshevik Revolution. (Photo by Ivan Sekretarev/AP Photo)

Israeli soldiers play the parts of wounded civilians during a drill simulating a toxic spill from an attack on a train in Beersheba, southern Israel, 13 January 2016, as Home Front medical teams, fire fighters and police carry out rescue operations. The large scale drill is the concluding exercise of the Fourth International Conference on Healthcare System Preparedness and Response to Emergencies and Disasters and includes some 200 of the world's experts on health system readiness from around the world. The conference is dealing with all types of medical emergencies from terrorist attacks to natural disasters. (Photo by Jim Hollander/EPA)

Four hundred buyers from around the world join 260 diamond manufacturing and trading firms on International Diamond Week as some 1,500 people are expected to trade more than billion of polished diamonds this week in Ramat Gan, Israel on February 16, 2016. The Israel Diamond Exchange is considered the most secure in the world, covering an area of 100,000 square meters with 3,500 bourse members. (Photo by Nir Alon via ZUMA Wire)

Sweet-toothed jet setters don't even need their passports for this worldwide tour, as they can travel around the world in 40 cakes. Some of the world's most famous landmarks and cultures have been created by some of the best bakers, as featured in this month's edition of Cake Masters magazine. Pictured here is “Japan”. (Photo by Mimi Cafe Union/Mercury Press/Caters News)

John Hawkley and his wife Patty Hawkley stand next to their 2,058 pound pumpkin and celebrate after winning the 41st Annual Safeway World Championship Pumpkin Weigh-Off on October 13, 2014 in Half Moon Bay, California. John Hawkley of Napa, California won the 41st Annual Safeway World Championship Pumpkin Weigh-Off and broke a state record with his gigantic pumpkin weighing in at 2,085 pounds. Hawkley took home a cash prize of $12,510, or $6.00 a pound. (Photo by Justin Sullivan/Getty Images)

A policeman looks at a car crushed underneath a collapsed bridge in Belo Horizonte, Brazil, Thursday, July 3, 2014. The overpass under construction collapsed Thursday in the Brazilian World Cup host city. The incident took place on a main avenue, the expansion of which was part of the World Cup infrastructure plan but, like most urban mobility projects related to the Cup, was not finished on time for the event. (Photo by Victor R. Caivano/AP Photo)

Among the fish populations that could be harmed by the Xayaburi dam in Laos is the critically endangered Mekong giant catfish, considered by the Guinness Book of World Records to be the world’s largest freshwater fish. The fish, which grows to 650 pounds and about 10 feet long, is only found in the Mekong River. It is migratory, moving between downstream habitats in Cambodia upstream to northern Thailand and Laos each year to spawn. Some experts fear the Xayaburi dam could block the migration and drive the giant catfish to extinction. (Photo by Courtesy of Zeb Hogan/University of Nevada, Reno)

A handout picture provided by Solar Impulse on 18 March 2015 shows the Swiss solar-powered plane Solar Impulse 2, HB-SIB, taking off with Swiss explorer Andre Borshberg on board for the third leg Ahmedabad to Varanasi, of the Round-The-World, in Ahmedabad, India, 18 March 2015. Swiss explorers Bertrand Piccard and Andre Borschberg attempt to circumnavigate the world flying with an aircraft, with a 72 metres wingspan, powered only by solar energy without a drop of fuel. (Photo by EPA/Solar Impulse)