A solar-powered plane takes off from Jiangbei International Airport in southwest China's Chongqing Municipality, Tuesday, April 21, 2015. The Solar Impulse 2 departed Chongqing on Tuesday for a 1190-kilometer (642-mile) flight to the city of Nanjing in eastern China, the sixth leg of its around-the-world flight. (Photo by Chinatopix via AP Photo)

A resident gestures about the loss of his home following an overnight fire at the Addition Hills area in suburban Mandaluyong city east Manila, Philippines, Monday, November 14, 2016. Fire officials say the overnight fire destroyed hundreds of homes, rendered more than 5,000 people homeless and resulted in the death of two residents. (Photo by Bullit Marquez/AP Photo)

In this picture taken on September 24, 2016, relatives grieve their lost one, an alleged drug user/dealer gunned down by unidentified gunmen in Manila. Philippine President Rodrigo Duterte defended his threat to kill criminals as “perfect” and vowed no let-up in his war on crime, as the death toll surged past 3,700. (Photo by Noel Celis/AFP Photo)

A mobile phone cover with a picture of Russian President Vladimir Putin and which reads “Mr President” is seen in this photo illustration taken a in hotel room in Kazan, Russia, July 30, 2015. He may be in charge of an economy in crisis, but if mobile phone covers and souvenir mugs are a barometer of popularity, Russian President Vladimir Putin need not fear for his political future. In fact, Moscow's annexation of Crimea from Ukraine last year has given the memorabilia makers even more material to glorify, sometimes wryly, a president whose image as a champion of Russian national interests in a hostile world is barely challenged in his own country. (Photo by Stefan Wermuth/Reuters)

Mrs. Marie Graskamp of Milwaukee shows the different positions one might assume when entering the bomb shelter in Milwaukee September 3, 1958. This circular entrance is about three feet in diameter. This is the entrance (according to the builders) that would connect to the cellar of a home assuming the shelter was in the ground for added protection. If a bombing should occur, all members of family would proceed to the cellar and then through the circular port into the shelter. (Photo by AP Photo)

A “Maya” girl sits in an altar during the traditional celebration of “Las Mayas” on the streets in Madrid, Spain Sunday, May 10, 2015. The festivity of the Maya comes from pagan rites and dates from the medieval age, appearing in ancient documents. It takes place every year in the beginning of May and celebrates the beginning of the spring. Girls between 7 and 11 years old are chosen as “Maya” and should sit still, serious and quiet for a couple of hours in altars on the street decorated with flowers and plants and afterwards they walk to the church with their family where they attend a ceremony. (Photo by Daniel Ochoa de Olza/AP Photo)

Francisco Javier Moreno (L), 35, and his wife Maria Auxiliadora Canca, 34, dressed as bandits pose for a photo with their horse as they participate in the third edition of “Ronda Romantica” (Romantic Ronda) in Ronda, southern Spain, May 16, 2015. Ronda Romantica is a cultural, historical and tourist event during the three days where thousands of people of Ronda and about fifty towns around of “Serrania de Ronda” (Ronda Mountain Ranges), dressed in traditional costumes, recreate the era of the bandits, drovers and romantic travelers in the nineteenth century. (Photo by Jon Nazca/Reuters)

Li Tingting, second from right, laughs as she is lifted off the ground by her wife Teresa Xu, right, outside of a beauty salon where the two were preparing for their wedding as clerks from an adjacent shop look on in Beijing, Thursday, July 2, 2015. Li, a 25-year-old prominent women's rights activist who was released from detention in April, held the wedding ceremony with her partner Teresa on Thursday and announced their marriage in an effort to push for LGBT (lesbian, gay, bisexual, and transgender) rights in China. (Photo by Mark Schiefelbein/AP Photo)