South Korean special warfare command soldiers participate in winter military training exercise on January 11, 2012 in Pyeongchang-gun, South Korea. The South Korean troops train in temperatures below -20 degrees celsius to defend the country against any possible attacks from North Korea. (Photo by Chung Sung-Jun/Getty Images)

Hot air balloons take part in the 38th International Balloon Festival of Chateau-d'oex, Switzerland, 23 January 2016. For nine days balloonists from 15 countries take part in the ballooning event in the Swiss mountain resort famous for ideal flight conditions due to an exceptional microclimate. The festival takes place from 23 to 31 January. (Photo by Cyril Zingaro/EPA)

A view of a Van Gogh-inspired hot air balloon being inflated during the Philippine International Hot Air Balloon Fiesta at Clark Freeport Zone in Pampanga province, north of Manila February 12, 2015. According to the organizer, a total of 32 hot air balloons are part of the four-day event. (Photo by Erik De Castro/Reuters)

In this photo provided by Andreas Langreiter via Global-Newsroom, Hannes Arch of Austria performs during the finals of the first stage of the Red Bull Air Race World Championship in Abu Dhabi, United Arab Emirates, Saturday, February 14, 2015. (Photo by Andreas Langreiter/AP Photo/Global-Newsroom)

Workers prepare Koshary, a popular Egyptian dish, in an attempt to break the Guinness World Record for the world's biggest plate of Koshary, at a general garden in Zamalek, Cairo, January 17, 2015. Koshary is a traditional Egyptian dish dating to the 19th century in which rice, pasta and lentils are mixed together in one plate with a topping of spicey tomato sauce and some crispy fried onions. With a huge plate of koshary measuring 10 metres long and in width and of 1.2 metres in height, the plate weighed 7 tonnes, or about 7,000 kg. About 6,000 attendees turned up to the festival, earning it a place in the world record books. (Photo by Mohamed Abd El Ghany/Reuters)

Reem Fawzy (L), the director of the Pink Taxi company, stands with her drivers in a parking lot in Cairo, Egypt, September 6, 2015. Pink uniforms, a pink logo on the cars, and even pink nail polish – it's all part of the look of women-drivers working for Egypt's first women-only taxi service. The Pink Taxi company hires only women drivers and gives rides to only female passengers. The company was started in an effort to provide a safe taxi service for women in a country with high rates of sexual harassment, said Reem Fawzy, the director of the company. (Photo by Amr Abdallah Dalsh/Reuters)

A man photographs the main engines of the space shuttle orbiter Discovery on display at the Udvar-Hazy Smithsonian National Air and Space Annex Museum in Chantilly, Virginia August 28, 2015. Shuttle Discovery had 27 years of service and flew 39 times before being retired in 2011. (Photo by Gary Cameron/Reuters)