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)

British singer Rita Ora arrives for the Echo Award at Messe Berlin on April 12, 2018 in Berlin, Germany. (Photo by Andreas Rentz/Getty Images)

Saint Nicholas poses with students during a traditional parade in central Brussels, Belgium December 3, 2016. (Photo by Yves Herman/Reuters)

The dominant woman in a leather dress with a stack and a whip in her hand. Bdsm outfit. (Photo by Getty Images)

A woman sits next to a Gollum figure on the “Middle-earth Shuttle” subway train November 18, 2003 in New York City. The train's cars were decorated with Middle-earth creatures, vines, moss and stones to celebrate the November 18 DVD and VHS release of the Special Extended Edition of The Lord of the Rings: The Two Towers. (Photo by Mario Tama/Getty Images)

Park Ji-soo of South Korea performs her contemporary variation during the final of the 43rd Prix de Lausanne at the Beaulieu Theatre in Lausanne February 7, 2015. The Prix de Lausanne is an annual international dance competition for dancers aged 15 to 18. A total of 67 participants from 18 countries were selected from 300 applicants to take part in this year's week-long competition, from which the jury has shortlisted 20 finalists to compete for Saturday's finals. Six of this year's finalists will be awarded a one-year all expenses paid scholarship at one of the Prix de Lausanne's partner schools or companies, among the most prestigious in the world. (Photo by Denis Balibouse/Reuters)

A model wears an Apache costume in the kids carnival during The 13th Jember Fashion Carnival 2014 on August 21, 2014 in Jember, Indonesia. The 13th Jember Fashion Carnival (JFC) 2014 theme is “Triangle, Dynamic in Harmony” and consists of ten parades which include Mahabharata, Tambora, Phoenix, Pine Forest, Apache, Borobudur, Flying Kite, Wild Deers, Stalagmite, and Chemistry. This street carnival is claimed to be one of the biggest in the world and comprises more than 850 performers parading along 3.6 km road used as the catwalk. (Photo by Robertus Pudyanto/Getty Images)

“The Skeleton Krewe was founded in 1999 by Christopher Kirsch. Inspired by the early days of Carnival before tractors and floats replaced walking processions, the Krewe has become one of New Orleans' premier marching clubs. The Krewe began actively marching as a small group of friends, but has grown to 40 active members”. – The Skeleton Krewe. Photo: “The Skeleton Krewe 2013 – Manning”. (Photo by Kevin O'Mara)