Young couples compete in Rock' n'Roll & Co, an all- Russian acrobatic rock' n'roll competition in Kazan, Russia on November 4, 2017. Acrobatic rock’n’roll is a discipline for couples combining energetic dancing with acrobatic moves. (Photo by Yegor Aleyev/TASS via Getty Images)

The homemade Airbus A320 jet plane made by Chinese farmer Zhu Yue is being built at an open space in Kaiyuan city, northeast China's Liaoning province on February 4, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)

Five micropigs born to mother, “Truffel”, are seen in Zoo Wuppertal on August 11, 2014 in Wuppertal, Germany. The five micropigs are the major attraction of Zoo Wuppertal. Pigedy, Fiete, Frederik, Smartie are 4 males and is Keks is a female micropig. (Photo by Animal Press/Barcroft Media)

Izzy Paskowitz helps Nixee Grace Chanowsky, 4, catch a wave Monday, August 18, 2014 at Wrightsville Beach, N.C. during the Annual Surfers Healing event for children with autism. Hundreds of people made their way to the beach to watch and cheer on the camp that was founded by Israel and Danielle Paskowitz. (Photo by Mike Spencer/AP Photo/The Star-News)

Virgin Galactic's new spaceship N202VG (bottom L) is seen behind the WhiteKnightTwo carrier aircraft mothership (front), which landed safely after splitting from SpaceShipTwo, in a hangar at Mojave Air and Space Port in Mojave, California, November 4, 2014. (Photo by Lucy Nicholson/Reuters)

Lazar and his sister Andjelka sit by a candle in their home in the eastern Serbian town of Majdanpek, December 4, 2014. Electricity workers in Serbia struggled through snow, ice and treacherous terrain on Thursday to restore electricity to an eastern town left shivering without power, heating or running water for a fourth day. (Photo by Marko Djurica/Reuters)

Police detain Sebahat Tuncel, co-chair of the pro-Kurdish Democratic Regions Party (DBP), during a protest against the arrest of Kurdish lawmakers, in the southeastern city of Diyarbakir, Turkey, November 4, 2016. (Photo by Sertac Kayar/Reuters)

Sap runs out of a frankincense tree near Mader Moge, Somaliland, a breakaway region of Somalia on August 4, 2016In a tradition dating to Biblical times, men rise at dawn in the rugged Cal Madow mountains of Somaliland in the Horn of Africa to scale rocky outcrops in search of the prized sap of wild frankincense trees. (Photo by Jason Patinkin/AP Photo)