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)

Record snowfall in the Sahara Desert near the town of Ain Sefra in Algeria on January 21, 2017. (Photo by Geoff Robinson/Rex Features/Shutterstock)

Baka pygmies in their forest home preparing food in, Sangha Forest, Central African Republic, February 2016. Here, in their forest home, traditional life continues in the face of multiplying challenges ranging from poachers, to ill health. Deep in the rainforests of central Africa lives one of the world’s most mysterious tribes. (Photo by Susan Schulman/Barcroft Images)

This happy couple started married life on top of the world, having exchanged their vows on mount Everest. Dressed in a full suit and wedding dress, James Sissom and Ashley Schmieder spent days scaling the mountain range in order to be photographed in front of such a breathtaking backdrop. Here: James Sissom and Ashley Schmieder exchange vows on Everest. (Photo by Charleton Churchill/Caters News Agency)

Scared of Heights. “Taken from the highest residential building in Asia: the Zenith in Busan. This was taken with official permission (which took me months to get) and safety measures were taken. I had to hang myself over the edge to get this shot. Not for the faint of heart! But when you’re at a height like this, the world below you just seems different. It takes away the fear one would normally have, and gives a sense of peace instead”. (Photo by Albert Dros/NatGeo Cities Travel Photographer of the Year 2017)

“Kopi luwak (Malay pronunciation), or civet coffee, is one of the world's most expensive and low-production coffee. It is made from the beans of coffee berries which have been eaten by the Asian Palm Civet (Paradoxurus hermaphroditus) and other related civets, then passed through its digestive tract. ...

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

A villager pours brine into troughs at ancient salt fields on May 5, 2005 in Yantian Village on Hainan Island, China. (Photo by China Photos/Getty Images)