Macro or Micro? Scientists’ pictures baffle our sense of scale. It began when Stephen Young, a geography professor at Salem State University in Massachusetts, tricked his biologist colleague Paul Kelly into thinking a satellite image was one of his electron microscope scans. Can you guess whether they are close-up or very far away? (Photo by Paul Kelly)

A Russian female military cadet marches in front of the Eternal Flame at the WWII memorial complex at Poklonnaya Hill in Moscow on February 17, 2021, during a rehearsal for the upcoming February 23's Defender of the Fatherland Day. (Photo by Alexander Nemenov/AFP Photo)

Real Madrid's Brazilian striker Vinicius Jr. (R) held by a Cadiz's defender during the Spanish LaLiga soccer match between Real ​Madrid and Cadiz, in Madrid, Spain, 10 November 2022. (Photo by Juanjo Martin/EPA/EFE)

A woman aims a World War II machine gun at a military show during celebration of the Defenders of the Fatherland Day in St.Petersburg, Russia, Tuesday, February 23, 2016. The day, celebrated in Russia on February 23, honors the nation's military and is a nationwide holiday. (Photo by Dmitri Lovetsky/AP Photo)

Looking for love by Tony Wu, USA. Highly commended, Animal Portraits. “Accentuating his mature appearance with pastel colours, protruding lips and an outstanding pink forehead, this Asian sheepshead wrasse sets out to impress females and see off rivals, which he will head-butt and bite, near Japan’s remote Sado Island. Individuals start out as females, and when they reach a certain age and size – up to a metre (more than 3 feet) long – can transform into males. Long-lived and slow-growing, the species is intrinsically vulnerable to overfishing”. (Photo by Tony Wu/2018 Wildlife Photographer of the Year)

Young cheetahs eat meat at The Cheetah Conservation Fund (CCF) center in Otjiwarongo, Namibia, on August 13, 2013. The CCF started breeding Anatolian livestock dogs to promote cheetah-friendly farming after some 10,000 big cats – the current total worldwide population – were killed or moved off farms in the 1980s. Up to 1,000 cheetahs were being killed a year, mostly by farmers who saw them as livestock killers. But the use of dogs has slashed losses for sheep and goat farmers and led to less retaliation against the vulnerable cheetah. (Photo by Jennifer Bruce/AFP Photo)

A Republican farmer defending a farm on the outskirts of Irun against Nationalist forces during the Spanish Civil War, 6th September 1936. A comrade lies dead by his side. (Photo by Keystone/Hulton Archive/Getty Images)