A large bull walrus returns to the shores of Prins Karl Forland after diving and feeding on clams. (Photo by Paul Nicklen/National Geographic). Svalbard, Norway, 2011

Parade-goers walk in the annual West Indian Day Parade on September 02, 2019 in the Brooklyn borough of New York City. The annual celebration of Caribbean culture is one of the largest of its kind and features dozens of floats and costumed participants that make their way down Flatbush Avenue. (Photo by Yana Paskova/Getty Images)

A boy bursts a soap-bubble at Gorky Park in Moscow on July 19, 2017. (Photo by Mladen Antonov/AFP Photo)

Austrian Bodybuilder and actor Arnold Schwarzenegger has some fun at a party on a yacht in Marina Del Rey in September 1979 in Los Angeles, California. (Photo by Michael Ochs Archives/Getty Images)

A long exposure photograph shows a tree burning during the Kincade fire off Highway 128, east of Healdsburg, California on October 29, 2019. California braced on October 29 for the most powerful winds this season that threaten to spread destructive fires raging in the state and could spark new blazes. (Photo by Philip Pacheco/AFP Photo)

Pedestrians cover their face as they walk along the dusty road in Kathmandu, Nepal February 27, 2017. Nepal has forced 2,500 old vehicles off roads in its capital city of Kathmandu, part of a fight against alarming air pollution levels that have hit nine times World Health Organisation (WHO) limits. Air pollution has been a chronic problem in rapidly growing Kathmandu, which sits in a Himalayan valley and is home to more than 3mn people. (Photo by Navesh Chitrakar/Reuters)

A wide-angle view shows the ascent of the shuttle Challenger on January 28, 1986. In the seconds after ignition, the rocket engines' hot blast began the process of destruction. (Photo by NASA)

A man holds a girl as she tries to escape when she realised she is to to be married, about 80 km (50 miles) from the town of Marigat in Baringo County, Kenya, December 7, 2014. As Pokot tradition dictates, the future husband arrived to her family home with a group of men to collect the girl. The men arrived with the last settled dowry of livestock for the girl's family. In this case it was 20 goats, three camels and 10 cows, given during a period of several weeks. (Photo by Siegfried Modola/Reuters)