A woman dressed as the Star Trek character “Leeta” (C) and man dressed as “Rom” (2R) arrive to attend the “Destination Star Trek London” convention at the ExCeL centre on October 19, 2012 in London, England. The three-day convention, which opened to the general public today, will be attended by all five actors who played captains throughout the 46-year-old series. (Photo by Oli Scarff)

U.S. Air Force pilots with the Thunderbirds perform the calypso pass maneuver in F-16 Fighting Falcon aircraft during a practice session prior to the Gunfighter Skies air show at Mountain Home Air Force Base, Idaho, September 19 and released September 24, 2014. (Photo by Tech. Sgt. Manuel J. Martinez/Reuters/US Air Force)

Students receive a group punishment during a military-style close-order drill class at the Qide Education Center in Beijing February 19, 2014. The Qide Education Center is a military-style boot camp which offers treatment for internet addiction. As growing numbers of young people in China immerse themselves in the cyber world, spending hours playing games online, worried parents are increasingly turning to boot camps to crush addiction. Military-style boot camps, designed to wean young people off their addiction to the internet, number as many as 250 in China alone. (Photo by Kim Kyung-Hoon/Reuters)

In this Saturday, May 7, 2016 photo, Afghan refugee Shazia Lutfi, 19, peeks through the door of her room at the former prison of De Koepel in Haarlem, Netherlands. The government has let Belgium and Norway put prisoners in its empty cells and now, amid the huge flow of migrants into Europe, several Dutch prisons have been temporarily pressed into service as asylum seeker centers. (Photo by Muhammed Muheisen/AP Photo)

Tribesmen loyal to the Houthi movement perform the Baraa dance during a gathering to show support to the movement in Sanaa, Yemen, May 19, 2016. Bara or Baraa dance is one of the several traditional outdoor dances performed by men in the country of Yemen. Bara dance literally means a dagger dance, where each dancer holds a dagger. The style of the Bara dance differs from tribe to tribe. It is performed on special occasions. (Photo by Khaled Abdullah/Reuters)

A Nepalese Hindu boy in festival attire walks in a procession during “Gai Jatra”, or Cow Festival in Kathmandu, Nepal, Friday, August 19, 2016. Members of Nepal's Newar Community celebrate the festival in memory of their family members who died the preceding year, believing that the cow will guide them in their journey to heaven. (Photo by Niranjan Shrestha/AP Photo)

Photo taken on September 19, 2015 shows a baby Brazilian opossum at the “Parque Estoril” zoo in Sao Bernardo do Campo of Sao Paulo, Brazil. According to local press, the “Parque Estoril” zoo houses currently 23 orphan cubs of wild animals rescued in the south region of Sao Paulo, victims of illegal wildlife trade or problems caused by urban growth. According to the zoo, all the animals arrived in the last three months, and many of them, not being able to be reintroduced to their natural habitat, will be used as examples in environmental education classes. (Photo by Rahel Patrasso/Xinhua via ZUMA Wire)

A devotee of the Chinese Jui Tui Shrine has his face pierced with metal rods during a street procession during the annual Vegetarian Festival in the southern Thai town of Phuket on October 19, 2015. During the festival, which begins on the first evening of the ninth lunar month and lasts nine days, religious devotees slash themselves with swords, pierce their cheeks with sharp objects and commit other painful acts to purify themselves, taking on the sins of the community. (Photo by Nicolas Asfouri/AFP Photo)