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 visitor is dwared between the wheels of BelAZ 450-ton dump truck (L) and BelAZ 360-ton dump truck (R) at the plant of Belarusian manufacturer of heavy trucks and equipment for earthmoving, BelAZ, in Zhodino, some 55 km from Minsk, Belarus, 27 August 2019. The company mostly delivers its products to CIS mining companies, mainly from Russia and Ukraine. (Photo by Tatyana Zenkovich/EPA/EFE/Rex Features/Shutterstock)

A 180 degrees rotated photograph shows the shadows of Polina (L), a six-year-old Belarusian first grade school girl, and her father, cast on the street while on their way to Polina's first day of school, which marks the traditional start of the academic year, in Minsk, Belarus, 02 September 2019. The start of a new academic year in Belarus, officially called Day of Knowledge, is a festive day for all school and university students in the country. (Photo by Tatyana Zenkovich/EPA/EFE)

Two young dancers take pictures while waiting for the start of the Koenji Awa-Odori dance festival, in the Koenji neighborhood of Tokyo. Saturday, August 24, 2019, Started in the 1950s, the Koenji Awa-Odori has grown to be one of Tokyo's largest and most popular summer festivals an estimated 10,000 dancers participating in the dance festival. Hundreds of thousands of spectators gather in the neighborhood to watch the two-day summer spectacle. The event is held on the last weekend of August each year. (Photo by Jae C. Hong/AP Photo)

People run as Haiti's Senator Jean Marie Ralph Fethiere (PHTK) fires a gun in the air, injuring Chery Dieu-Nalio, a photographer for Associated Press, while facing opposition supporters in the parking lot of the Haitian Parliament and Senate, as the government attempted to confirm the appointment of nominated Prime Minister Fritz William Michel, in Port-au-Prince, Haiti on September 23, 2019. (Photo by Andres Martinez Casares/Reuters)

A young female demonstrator is arrested by police during clashes in the Causeway Bay area of Hong Kong, China on October 6, 2019. Hundreds of thousands of protesters marched through the city's streets in defiance of the new “no-mask” law, which was introduced two days ago as demonstrations roll into a 14th week. (Photo by Rick Findler/EPA/EFE/Rex Features/Shutterstock)

A fado singer smokes a cigarrette outside a fado house at the Alfama neighborhood in Lisbon on May 8, 2019. From fado sounds to Cape Verde mornas or bossa nova: the Lisbon nights, where musicians from all over the world meet, have largely inspired Madonna's new album, who has been in the Portuguese capital since 2017. (Photo by Patrícia de Melo Moreira/AFP Photo)

A Spanish national police officer uses his club to hit a protester during a demonstration called the Catalan pro-independence left youth group “Arran” on October 19, 2019 in Barcelona, a day after nearly 200 people were hurt in another night of violent clashes in Catalonia. The deterioration came on the fifth consecutive day of protests in the Catalan capital and elsewhere over a Spanish court's jailing of nine separatist leaders on sedition charges over a failed independence bid two years ago. (Photo by Josep Lago/AFP Photo)