Vietnamese military personnel in traditional dress take part in a parade celebrating the 40th anniversary of the end of the Vietnam War which is also remembered as the fall of Saigon, in Ho Chi Minh City, Vietnam, Thursday, April 30, 2015. (Photo by Dita Alangkara/AP Photo)

A man works on a small replica of the Iron Man armor next to a homemade replica of the “Hulkbuster” Iron Man armour from the movie “Avengers: Age of Ultron”, at an underground parking lot in Zhengzhou, Henan province, China, May 12, 2015. The 3.4-metre-tall replica is made of over 100 fiber-reinforced plastic components. It took Xing and his friends two months to put them together after watching the trailer of the movie in March, local media reported. (Photo by Reuters/Stringer)

Robot couple Xiaolan (L) and Xiaotao carry trays of food at a restaurant in Jinhua, Zhejiang province, China, May 18, 2015. The restaurant, which opened on Monday, has two robots delivering food for customers. The robots were designed as a couple, Xiaolan and Xiaotao, according to local media. (Photo by Reuters/Stringer)

Actress Bai Ling poses for a picture in front of St. Basil's Cathedral at the Red Square in Moscow, Russia, July 1, 2015. (Photo by Ivan Burnyashev/Reuters)

A Hindu woman gives money to an elephant outside the Lord Jagannath temple ahead of the annual Rath Yatra, or chariot procession, in Ahmedabad, India, July 16, 2015. The annual religious procession commemorates a journey by Hindu god Jagannath, his brother Balabhadra and sister Subhadra, in specially made chariots. The annual Rath Yatra is celebrated on July 18. (Photo by Amit Dave/Reuters)

ESA astronaut Samantha Cristoforetti on the International Space Station 3 February 2015 during her Futura mission. Samantha is living and working on the Station as part of the Expedition 42 crew. Picture released on February 10, 2015. (Photo by ESA/NASA)

A man from the Dominican Republic wears a devil mask while dancing in the street during Carnival celebrations in Panama City, Monday, February 16, 2015. (Photo by Arnulfo Franco/AP Photo)

A performer takes part in the opening of the Temple Fair, part of Chinese New Year celebrations at Ditan Park, also known as the Temple of Earth, in Beijing, February 18, 2015. (Photo by Kim Kyung-Hoon/Reuters)