“Red Arrows” at the 2016 royal air tattoo, RAF Fairford, UK. By Jonny Williams, finalist: action. (Photo by Jonny Williams/UK National Geographic Traveller Photography Competition 2018)

Gray whale feeding at the surface and showing it's baleen. (Photo by Christopher Swann/Biosphoto)

“The Dragon and The Hopper”. Eyrean earless dragon (Tympanocryptis tetraporophora) standing tall on a very hot rock in western Queensland. For a short time it was joined by a hopper, who jumped off before becoming lunch. (Photo by Harrison Warne/Nature Conservancy Australia 2021 Photo Contest)

A handout photo made available by Limex Images of Pete McLeod of Canada (R) and Kirby Chambliss of the United States flying over the city of Kazan prior to the fifth stage of the Red Bull Air Race World Championship in Russia on August 22, 2018. (Photo by Joerg Mitter/EPA/EFE/Limex Images)

In this Thursday, April 16, 2015 photo provided by Robert MacFarlane, a raccoon climbs up a skyscraper in downtown Toronto. Social media was abuzz Thursday with the photo of the raccoon peering from between the metallic rungs of a crane 58 stories high. (Photo by Robert MacFarlane)

“The V-30 Warhawk was designed by Blackshaw Avionics as a long-range fighter and was primarily used by the Arcadian Air Force for escort duties. The plane pictured is the “Spirit of Freedom” and was one of the four planes that escorted the Arcadian Royal Airship during and after the Great War. The three other fighters were the “Spirit of Hope”, the “Spirit of Justice” and the “Spirit of Destiny”. All pilots were hand-picked by the Head of Airborne Forces and included some of the very finest pilots in the Kingdom. The crew consisted of one pilot and one gunner although both cabins were fitted so that if either crew member was killed the other could take over their duties. Each Warhawk was fitted with four Haverlock “Banshee” engines and four 24mm machine guns”. (Photo and comment by Jon Hall)

ESA astronaut Tim Peake posted this stunning image on his social media channels, commenting: “Station passed through magnificent aurora Australis last night”. Tim is set to return to Earth on 18 June 2016, bringing his six-month Principia mission to the ISS to an end. During his stay he performed more than 30 scientific experiments for ESA and taking part in numerous others from ESA's international partners. ESA and the UK Space Agency have partnered to develop many exciting educational activities around the Principia mission, aimed at sparking the interest of young children in science and space. (Photo by Tim Peake/ESA/NASA)

Growing cities, overuse of fertilizers and factory wastewater have degraded China's water supplies to the extent that half the nation's rivers and lakes are severely polluted. China aims to spend $850 billion to improve filthy water supplies over the next decade, but even such huge outlays may do little to reverse damage caused by decades of pollution and overuse in Beijing's push for rapid economic growth. Photo: Fishermen row a boat in the algae-filled Chaohu Lake in Hefei, Anhui province, June 19, 2009. (Photo by Jianan Yu/Reuters)