The competition, which is run by the Royal Observatory Greenwich in association with BBC Sky at Night Magazine, is now in its sixth year and has received over 2,500 entries. Photo: Centre of the Heart Nebula by Ivan Eder (Hungary). Situated 7500 light years away in the “W”-shaped constellation of Cassiopeia, the Heart Nebula is a vast region of glowing gas, energized by a cluster of young stars at its centre. The image depicts the central region, where dust clouds are being eroded and moulded into rugged shapes by the searing cosmic radiation. (Photo by Ivan Eder)

A group of dust covered child labourers gather for a portrait in the brick kiln in Kathmandu Valley, Nepal, 22 February 2015. Bleak photos identify the children working their fingers to the bone in Nepalís brick kilns. Photographer Jan Mˆller Hansen documented the conditions of the brick kilns in Kathmandu Valley, Nepal between 2013 and 2016 while he lived and worked in the area. Jan estimates between 150,000 and 175,000 people are employed in the 200 brick kilns littering the Kathmandu Valley. (Photo by Jan Moeller Hansen/Barcroft Images)

From Tibetan monks playing basket ball with ice thawing high up in the Himalayas, to the pollution that hides behind the Taj Mahal, here’s pick from 60 exceptional environmental photographs, by photographers and filmmakers from 70 countries, that will go on show at the Royal Geographical Society in London from 29 June to 21 August. The winners will be announced on 28 June. Here: Gravel Workmen of Chittagong, Bangladesh, by Faisal Azim. Gravel workmen look through a glass window at a gravel-crushing yard in Chittagong. Full of dust and sand, it is an extremely unhealthy environment for working, but still hundreds of people work here for their livelihoods. (Photo by Faisal Azim/2016 Atkins CIWEM Environmental Photographer of the Year)

These snaps capture true winter wonderlands – as Mother Nature's icy grip takes hold of America's National Parks. From snow-capped mountains in Yosemite to an icy still Glacier Bay, the incredible images show their beauty is year round. In other breath-taking shots crisp frost lines the paths through Great Smokey Mountains and Crater Lake has had more than a dusting of snow. Here: Apostle Island National Lakeshore Park in Wisconsin. (Photo by U.S. Department of the Interior/Cater News)

Revellers celebrate "Ash Monday" by participating in a colourful "flour war", a traditional festivity marking the end of the carnival season and the start of the 40-day Lent period until the Orthodox Easter,in the port town of Galaxidi, some 215 km (134 miles) north west of Athens, March 18, 2013. The revellers "fight" by throwing coloured flour, charcoal dust and powder painting until they essentially run out of supplies. (Photo by Yannis Behrakis/Reuters)

Talbot Lago T26 Grand sport SWB Saoutichik is displayed for auction during the Retromobile show in Paris, Tuesday, February 3, 2015. 60 rusting motors, which include a vintage Ferrari California Spider, a Bugatti and a very rare Maserati, were found gathering dust and hidden under piles of newspapers in garages and outbuildings at a property in France. The cars were collected from the 1950s to the 1970s by entrepreneur Roger Baillon, who dreamt of restoring them to their former glory and displaying them in a museum, but, his plans were dashed as his business struggled, forcing the sale of about 50 vehicles, to be auctioned off on Feb. 6. (Photo by Jacques Brinon/AP Photo)

A rainbow forms on water from a spray machine used to suppress coal dust at the Krasnogorsky open pit coal mine, operated by Mechel PJSC, in Mezhdurechensk, Russia, on Monday, July 19, 2021. Russia’s government is betting that coal consumption will continue to rise in big Asian markets like China even as it dries up elsewhere. (Photo by Andrey Rudakov/Bloomberg)

An exterior view of Rauceby, an abandoned mental asylum in Lincolnshire, UK. These haunting photos show the collapsing remains of a derelict mental asylum. The pictures show the ruined former hospital building and chapel, now covered in dust and graffiti. Few signs remain that reveal the site as a former home of mentally ill adults and children. (Photo by Simon Robson/Caters News)