This image obtained January 31, 2017 from the US Geological Survey's Hawaiian Volcano Observatory showing a lava stream, pouring out of the lava tube on the sea cliff at the Kamokuna ocean entry from the Kilauea Volcano on January 29. (Photo by AFP Photo/USGS)

In this April 4, 2017 photo keeper German Alonso straps a leg prothesis to on the left leg of secretarybird Soeckchen (Sagittarius seprentarius) at the bird park in Walsrode, northern Germany. The prothesis was made in a 3D-printer after his left leg was amputated. (Photo by Philipp Schulze/DPA via AP Photo)

Aerobatic aircrafts fly during a performance at the Airshow Zhengzhou 2017 in Zhengzhou, capital of central China's Henan Province on April 27, 2017. The 5-day air show kicked off in Zhengzhou on Thursday, aiming to build a general aviation gathering center for business and communications. (Photo by Li An/Xinhua via ZUMA Wire)

A person jumps on a trampoline before Nathan's Famous Fourth of July International Hot Dog-Eating Contest at Coney Island in Brooklyn, New York City, U.S., July 4, 2017. (Photo by Andrew Kelly/Reuters)

Richard Coleby of Polaris falls over his quad into muddy waters during day one of the HydroGarden Weston Beach Race on October 14, 2017 in Weston-Super-Mare, England. (Photo by Michael Steele/Getty Images)

Eagle Prime (MK3), a giant robot by MegaBots Inc. which manufactures giant piloted humanoid fighting robots headquartered in Berkeley, California on October 18, 2017. (Photo by Courtesy Michael Mauldin/Reuters/MegaBots Inc)

A worker applies colour to strings which will be used to fly kites, by a roadside in Ahmedabad, India, November 23, 2017. (Photo by Amit Dave/Reuters)

Undercover Israeli police arrest a Palestinian demonstrator during clashes following protests against U.S. President Donald Trump's decision to recognize Jerusalem as the capital of Israel, in the West Bank city of Ramallah, Wednesday, December 13, 2017. (Photo by Nasser Shiyoukhi/AP Photo)