Wooden doors and a stone path at the base of Fort Lovrijenac in Kolorina Bay, Dubrovnik (© Barbara Vallance/Getty Images)

Moraine Lake in Banff National Park, Alberta, Canada (© Schroptschop/Getty Images)

Cape foxes in the Kalahari Desert in South Africa (© NSP-RF/Alamy)

A scarlet Minivet during rainfall, West Bengal (© Debapratim Saha/Minden Pictures)

Great Point Light on Nantucket Island, United States (© Cate Brown/Cavan Images)

Tolbachik volcanic complex on the Kamchatka Peninsula, Russia (© Egor Vlasov/Shutterstock)

Enhanced-colour composite of the Caloris Basin, Mercury (© NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

Gray seal pup resting on a beach in Blakeney National Nature Reserve, England (© Kevin Sawford/Getty Images)

American Basin in San Juan Mountains, USA (© Blaine Harrington III/Alamy)

The bell tower in Lake Reschen in South Tyrol, Italy (© Scacciamosche/Getty Images)

Migrating flock of flamingos in Mumbai (© Gaurav Ojha/500px/Getty Images)

Ežezers Lake in the Latgale region, Latvia (© Eaglewood Films/Nimia)

Ežezers Lake in the Latgale region, Latvia (© Eaglewood Films/Nimia)

The Hoh Rainforest in Olympic National Park, Washington state (© Jorge Romano/Offset by Shutterstock)

The Panthéon in Paris, France (© manjik/Shutterstock)

Small tortoiseshell butterfly feeding on flower nectar, Lower Saxony, Germany (© Duncan Usher/Minden Pictures)

Happy hot air balloon (© Leonsbox/Getty Images Plus)

Nine-spotted moth in Switzerland (© Thomas Marent/Minden Pictures)

Nine-spotted moth in Switzerland (© Thomas Marent/Minden Pictures)

Earthrise across Mare Smythii on the moon (© Image Science and Analysis Laboratory, NASA-Johnson Space Center)

The town of Dinant and the River Meuse in Namur, Belgium (© Kadagan/Shutterstock)

Blue wildebeest herd migrating at sunset, Maasai Mara Game Reserve, Kenya (© Denis-Huot/Minden Pictures)

The Giant's Causeway, Bushmills, Northern Ireland, UK (© Chiara Salvadori/Getty Images)

Disko Bay, Ilulissat, Greenland (© Kertu/Shutterstock)

The valleys of Munnar, Kerala (© Through the beauty of Kerala ...../Getty Images)

Wheat field in Valladolid, Castilla y León, Spain (© Carlos Javier García Prieto/EyeEm/Getty Images)

Tamul waterfall in the state of San Luis Potosí, Mexico (© Robert Harding World Imagery/Offset by Shutterstock)

Tiger at the Bandhavgarh National Park, Madhya Pradesh (© Mint Images/offset by shutterstock)

Hamerkop standing on a hippo, Mana Pools National Park, Zimbabwe (© David Fettes/Getty Images)

The dome of the Charminar, Hyderabad (© Sujith Gopinath/shutterstock)

A lava flow hits water to create an explosion as a tourist boat passes, Hawaii Volcanoes National Park (© Patrick Kelley/Getty Images)