The 30th anniversary of the meltdown at the Chernobyl nuclear plant that caused large amounts of radioactive particles to be released into the air will be commemorated on April 26, 2016. Photojournalist Sean Gallup returned to the area to document the lasting effects of the world's worst nuclear power plant accident. Pictured, children's beds are seen in an abandoned kindergarten in Kopachi village located inside the Chernobyl exclusion zone, September 29, 2015, near Chernobyl, Ukraine. (Photo by Sean Gallup/Getty Images)

A pilot looks up from a U.S. F-22 Raptor fighter as it prepares to refuel in mid-air with a KC-135 refuelling plane over European airspace during a flight to Britain from Mihail Kogalniceanu air base in Romania April 25, 2016. (Photo by Toby Melville/Reuters)

A woman jumps with balloons while she poses for a picture at a park in Kiev, Ukraine May 6, 2018. (Photo by Valentyn Ogirenko/Reuters)

A woman with high heels walks on a sidewalk which is renovated on August 10, 2017 in downtown Moscow, as the city continues with preparations for next year's FIFA World Cup. (Photo by Mladen Antonov/AFP Photo)

A duck salesman parades his stock to commuters at a busy station in Dhaka, Bangladesh on May 23, 2018. (Photo by Nazmul Hasan Khan/Caters News Agency)

A USGS geologist making observations of the fissure 8 lava channel at sunset is pictured in this July 3, 2018 fisheye lens handout photograph near the Kilauea volcano eruption in Hawaii, U.S. (Photo by USGS/Handout via Reuters)

A hummingbird is photographed during the National Orchid Exhibition at the Jose Celestino Mutis Botanical Garden in Bogota, Colombia Septermber 20, 2018. Picture taken September 20, 2018. (Photo by Luisa Gonzalez/Reuters)

Graduates dance as they take part in a “Last school bell” ceremony at a school in Minsk, Belarus on May 30, 2018. (Photo by Vasily Fedosenko/Reuters)