A Soyuz capsule carrying International Space Station (ISS) crew members U.S. astronaut Scott Kelly, Russian cosmonauts Sergei Volkov and Mikhail Korniyenko descends beneath a parachute near the town of Dzhezkazgan (Zhezkazgan), Kazakhstan, March 2, 2016. (Photo by Kirill Kudryavtsev/Reuters)

Joe Deedon, president of TAC ONE Consulting, demonstrates searching for a shooter in a middle school during an Active Shooter Response course offered by TAC ONE in Denver April 2, 2016. According to TAC ONE, the course, which is offered for the first time to concealed weapons permit carrying civilians, is designed at preparing people to effectively save lives prior to the arrival of law enforcement at an active shooter incident. (Photo by Rick Wilking/Reuters)

A wolf looks into the camera at the 30 km (19 miles) exclusion zone around the Chernobyl nuclear reactor in the abandoned village of Orevichi, Belarus, March 2, 2016. What happens to the environment when humans disappear? Thirty years after the Chernobyl nuclear disaster, booming populations of wolf, elk and other wildlife in the vast contaminated zone in Belarus and Ukraine provide a clue. (Photo by Vasily Fedosenko/Reuters)

Jordanian soldiers pose after the opening ceremony of eighth annual Warrior Competition at the King Abdullah Special Operations Training Center (KASOTC) in Amman, Jordan, May 2, 2016. Twenty Seven Teams from Eleven countries are participating in a competition to test their military skills. (Photo by Muhammad Hamed/Reuters)

Chunhun (R), the leader of Japan's North Korea fan club called sengun-joshi, or military-first girls, and other members practice a Moranbong Band dance in Tokyo, Japan on November 2, 2017. (Photo by Toru Hanai/Reuters)

In this November 2, 2017 photo, Mathew Fulkerson and his wife Leigh Ann pose at their Subterra Airbnb located in a former underground missile silo base near Eskridge, Kan. It was designed to house a nuclear warhead six decades ago – but now, this Cold War silo is the perfect spot for a mini break at just $133 a night. (Photo by Thad Allton/The Topeka Capital-Journal via AP Photo)

Sudanese cattle keepers from Dinka tribe Makal Maker (R) and Achiek Butich pose with the guns for their protection at their cattle camp in Mingkaman, Lakes State, South Sudan, on March 2, 2018. (Photo by Stefanie Glinski/AFP Photo)

A replica of the bust of Nefertiti stands in the Replica Workshop of the National Museum of Berlin in Berlin, October 2, 2015. The workshop plans to produce 10 to 20 replicas a year, which like the original are made of a limestone core with gypsum finish. Each one will cost 8,900 euros (9,934 US Dollars). (Photo by Axel Schmidt/Reuters)