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)

Indian police detain a Tibetan activist during a protest held to mark the 57th anniversary of the Tibetan uprising against Chinese rule, outside the Chinese embassy in New Delhi, India, March 10, 2016. (Photo by Cathal McNaughton/Reuters)

A regional train passes fog-covered fields in Wehrheim near Frankfurt, Germany, early Friday, October 7, 2022. (Photo by Michael Probst/AP Photo)

Goats wait to get unloaded from a vehicle at a livestock market during Dashain, the biggest religious festival for Hindus in Nepal, in Kathmandu, Nepal October 4, 2016. (Photo by Navesh Chitrakar/Reuters)

Pride rally 2017 on fifth avenue in Manhattan, New York, June 25, 2017. Thouands cheered as members of LGBT community danced and marched under a bright summer sun. Many participants carried political themed signs as President Trump's adminstration has angered some in the LGBT community. (Photo by R. Umar Abbasi)

A window cleaner passes a lighter to his colleague while rappelling from a new building in Tianjin March 23, 2007. (Photo by Reuters/Stringer)

A girl plays on a pile of discarded flowers outside a market, the day after the Diwali celebrations in Mumbai, India October 31, 2016. (Photo by Shailesh Andrade/Reuters)

Members of the “Exit Point” amateur rope-jumping group jump from a 44-metre high (144-ft) waterpipe bridge in the Siberian Taiga area outside Krasnoyarsk, September 13, 2015. Rope-jumping, an extreme sport, involves jumping from a high point using an advanced leverage system combining mountaineering and rope safety equipment. (Photo by Ilya Naymushin/Reuters)