Undated handout issued by Take A View of Sunrise at Winnats Pass, Derbyshire, England which won the Visit Britian “You're invited” Award for the best image from an overseas entrant category in this year's Landscape Photographer of the Year Awards. (Photo by Sven Mueller/PA Wire)

A Philippine boy collects used plastic bottles to be sold at a junk shop at Divisoria market in Manila on November 29, 2017. (Photo by Noel Celis/AFP Photo)

Lightning strikes above Perch Rock Lighthouse in Merseyside, North West England on August 10, 2020. (Photo by Bav Media/The Sun)

Leslie Cliff and his wife Violet, English figure skating pair. Olympic games of Garmisch-Partenkirchen (Germany), 1936. (Photo by Roger Viollet Collection/Getty Images)

Gold medalists Kikkan Randall and Jessica Diggins of the United States dancing during the medal ceremony for Cross-Country Skiing – Ladies' Team Sprint Free on day 13 of the PyeongChang 2018 Winter Olympic Games at Medal Plaza on February 22, 2018 in Pyeongchang-gun, South Korea. (Photo by Eric Gaillard/Reuters)

A kid wearing rollerblades hitches a ride via motorbike, in Port-au-Prince, Haiti, Sunday, October 25, 2015. The country held the first-round presidential vote Sunday. Haitians chose between 54 presidential hopefuls and a slew of legislative and municipal candidates. (Photo by Ricardo Arduengo/AP Photo)

Behaviour: Mammals category. Giant Gathering by Tony Wu, USA. Dozens of sperm whales mingled noisily off Sri Lanka’s northeast coast, stacked as far down as Tony could see. This was a congregation of dozens of social units, like a gathering of the clans. Aggregations like this could be a critical part of the whales’ rich social lives but are rarely reported. Some two thirds of the population was wiped out before commercial whaling was banned in 1986. This kind of major gathering could be “a sign that populations are recovering”, says Tony. (Photo by Tony Wu/Wildlife Photographer of the Year 2017)

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)