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)

In a handout picture released by the British Ministry of Defence via their Defence News Imagery website on August 22, 2016, Nils Olav the penguin inspects the Guard of Honour formed by His Majesty the King of Norway's Guard on August 22, 2016 at Edinburgh Zoo in Scotland. His Majesty the King of Norway's Guard paid a very special visit to RZSS Edinburgh Zoo to bestow a unique honour upon resident king penguin Sir Nils Olav. Already a knight, the most famous king penguin in the world was given the new title of “Brigadier Sir Nils Olav”. (Photo by Mark Owens/AFP Photo)

Nursing and care personnel lay on the floor in the ICU unit, during a demonstration on International Nursing and Care day, at the Mont Legia Hospital in Liege, Belgium, Wednesday, May 12, 2021. Hospital personnel around Belgium took part in various actions around the country on Wednesday to highlight the work they do and demand better recognition. (Photo by Valentin Bianchi/AP Photo)

A motorist drives a car overloaded with vegetables and fruit on a street in Yaounde on July 25, 2022, prior to the French president's visit. (Photo by Ludovic Marin/AFP Photo)

Newlyweds take wedding photos hanging from bridge, Yueyang, Hunan province, China on August 9, 2016. They held such a special wedding ceremony on China's Qixi Festival. (Photo by Top Photo Corporation/Rex Features/Shutterstock)

Local residents crowd a swimming pool during a hot weather in Suining, Sichuan province, 27 July 2008. (Photo by Reuters/Stringer)

College students take shelter at a traffic point as a man paddles his rickshaw through a flooded road during heavy rain in Guwahati, India, June 13, 2017. (Photo by Anuwar Hazarika/Reuters)

Two brave contestants take part in the World Gravy Wrestling Championships at the Rose 'n Bowl in Stacksteads, Lancashire, England on August 27 2018. Contestants must wrestle in the gravy for 2 minutes, points are scored for fancy dress, comedy effect, entertainment and wrestling ability. The event is held to raise funds for the East Lancashire Hospice and competitors nominated charities. (Photo by The Mercury Press)