A family take a souvenir picture next to giant male panda Xiao Liwu, who was born at the San Diego Zoo and will be repatriated to China with his mother Bai Yun, bringing an end to a 23-year-long panda research program in San Diego, California, U.S., April 18, 2019. (Photo by Mike Blake/Reuters)

Some dozens of long-finned pilot whales lay dead on a remote beach in Iceland after they were discovered by tourists sightseeing in the Snaefellsnes Peninsula in western Iceland aboard a helicopter, Thursday July 18, 2019. The whales were concentrated in one spot on the beach, many partially covered by sand. (Photo by David Schwarzhans via AP Photo)

A devotee of Hindu goddess Kali performs a ritual during the “Bonalu” festival in Hyderabad, India, Sunday, July 28, 2019. Bonalu is a month-long Hindu folk festival of the Telangana region dedicated to Kali, the Hindu goddess of destruction. (Photo by Mahesh Kumar A./AP Photo)

Su Daocheng rides his home-made mechanical horse vehicle on a street in Shiyan, Hubei province January 18, 2015. Su spent 2 months making this 1.5 metre high and 2 metre long horse, which weighed 250 kilograms with 4 legs and 2 supportive wheels, local media reported. (Photo by Reuters/Stringer)

The Aurora Borealis seen across the sky in Lapland, Finland. The beautiful phenomenon was captured by photographer Marko Korosec on a trip to the arctic region of Lapland in Northern Finland. He used long exposures on his Canon DSLR to create the stunning images. (Photo by Marko Korosec/Barcroft Media)

This long exposure picture shows vehicles on roads during rush hour on the eve of the National Day holidays in Shanghai on September 30, 2014. According to local media, police checkpoints will be set up at highways, elevated roads and business hubs to tackle drunk driving during the National Day holiday. (Photo by Johannes Eisele/AFP Photo)

Danny McWilliams, 56, is seen at his 36-foot-long replica of Walt Disney movie version of the Nautilus submarine from Jules Verne's “20,000 Leagues Under the Sea” at his rural home in Ellijay, Georgia, USA, 04 December 2013. (Photo by Erik S. Lesser/EPA)

A visitor kneels on the 180-meter-high and 300 meter-long glass-bottomed suspension bridge at the Shiniuzhai National Geopark in Pingjiang county, in central China's Hunan province, 24 September 2015. (Photo by Jiao Zi/Imaginechina via AFP Photo)