Soap Bubble Structures by Kym Cox. Bubbles optimise space and minimise their surface area for a given volume of air. This phenomenon makes them a useful tool in many areas of research, in particular, materials science and “packing” – how things fit together. Bubble walls drain under gravity, thin at the top, thick at the bottom, which interferes with travelling lightwaves to create bands of colour. Black spots show the wall is too thin for interference colours, indicating the bubble is about to burst. (Photo by Kym Cox/2019 Science Photographer of the Year/RPS)

A giant storm cloud can be seen in the sky above swimmers near Mollymook Beach, south of Sydney, March 5, 2014. (Photo by David Gray/Reuters)

This 2014 series Shanghai Tian Wa saw Chinese photographer Liu Tao train his lens on two distinct districts in Shanghai. Here: “Shanghai Tian Wai №26, 2014”. (Photo by Liu Tao/The Guardian)

Young category winner. Great autumn morning by Fabian Dalpiaz. (Photo by Fabian Dalpiaz/2018 Astronomy Photographer of the Year)

His majesty King Jigme Khesar Namgyel Wangchuck (L), 31, smiles at his bride during the purification marriage ceremony to Queen Jetsun Pema, 21, in the historical Punakha Dzong on October 13, 2011 in Punakha, Bhutan. The Dzong is the same venue that hosted the King's historic coronation ceremony in 2008. The Oxford-educated king is popular in the country and the ceremony will be followed by celebration in the capital and countryside. (Photo by Paula Bronstein/Getty Images)

Margaret Morris dancers exercising on the sands at Saint-Idesbald. (Photo by Fox Photos/Getty Images). August 1929

A Los Angeles County firefighter puts water a burning house in a wildfire in the Lake View Terrace area of Los Angeles Tuesday, December 5, 2017. Ferocious winds in Southern California have whipped up explosive wildfires, burning a psychiatric hospital and scores of other structures. Tens of thousands of people have been ordered evacuated. (Photo by Chris Carlson/AP Photo)

“A Balinese man shows off his pride and joy, a fighting cock, while on a cigarette break after a morning’s work in nearby fields”. (Photo by Coltrane Koh/The Guardian)