Lion cub and mother, Sabi Sabi, South Africa (© Andrew Coleman/Getty Images)

Harp seal, Jones Beach, Long Island, New York, USA (© Vicki Jauron, Babylon and Beyond Photography/Getty Images)

Prague, Czech Republic (© benkrut/Getty Images)

The Lick Observatory, Mount Hamilton, California, USA (© Jeffrey Lewis/Tandem Stills + Motion)

Borrego Badlands, Anza-Borrego Desert State Park, California, USA (© Tom Hogan/plainpicture)

Ptarmigan (lagopus muta) in snow, Scotland (© David Chapman/Alamy Stock Photo)

Kochelsee and Heimgarten mountain, Bavaria, Germany (© Reinhard Schmid/eStock Photo)

Fort of São Miguel Arcanjo, Nazaré, Portugal (© Richard A Lock/Getty Images)

American bison, Yellowstone National Park, Wyoming, USA (© Steve Gettle/Minden Pictures)

Rice field, Dhamrai, Dhaka, Bangladesh (© Amazing Aerial Agency/Offset by Shutterstock)

Ski touring, High Tauern mountain range, Austria (© RooM the Agency/Alamy)

Porcupine hangs on a willow tree branch, Alaska, USA (© Design Pics/Danita Delimont)

Mount Fanjing, Guizhou province, China (© zhuxiaophotography/Shutterstock)

Aurora borealis, Tasiilaq, Greenland (© Shane P. White/Minden Pictures)

Road to Sa Calobra, Majorca, Spain (© Tolo Balaguer/agefotostock)

To Sua Ocean Trench, Upolu island, Samoa (© Chris McLennan/Alamy)

Chilli peppers, Bogra, Bangladesh (© Amazing Aerial Agency/Offset/Shutterstock)

Rydal Water, Lake District, Cumbria, England (© Tranquillian1/iStock/Getty Images Plus)

Burghausen town and Salzach river, Bavaria, Germany (© Harald Nachtmann/Moment/Getty Images)

Saint Elias Mountains and Kaskawulsh Glacier, Kluane National Park and Reserve, Yukon, Canada (© Design Pics Inc/Alamy)

Adélie penguin, Graham Passage, Antarctic Peninsula, Antarctica (© Nick Garbutt/Minden Pictures)

Martinique, Lesser Antilles, Caribbean Sea (© Airpano LLC/Amazing Aerial Agency)

Meoto Iwa (Wedded Rocks), Ise, Mie Prefecture, Honshu, Japan (© Marco Gaiotti/plainpicture)

Lower Manhattan, New York City, USA (© New York On Air/Offset/Shutterstock)

Tŵr Mawr lighthouse, Llanddwyn Island, Anglesey, Wales (© Joe Daniel Price/Getty Images)

Mehrangarh Fort, Jodhpur, Rajasthan, India (© Jayakumar/Shutterstock)

Bluespotted ribbontail ray near Perth, Australia (© Jeff Rotman/Minden Pictures)

Short-eared owl hunting at dusk in Worlaby Carrs, Lincolnshire (© Ben Hall/Minden Pictures)

Brain coral, Caribbean Sea near Grand Cayman, Cayman Islands (© Alex Mustard/Minden Pictures)

Halo around the Sun, Ore Mountains, Saxony, Germany (© Martin Ruegner/Getty Images)

Workers in an incense field, Huyện Ứng Hòa district of Hanoi, Vietnam (© Azim Khan Ronnie/Amazing Aerial Agency)