A meerkat in Namibia (© Danita Delimont/Offset by Shutterstock)

Wakatobi National Park, Indonesia (© Fabio Lamanna/Alamy)

Greater flamingos migrate to fresh water in India (© Amresh Mishra/500px/Getty Images)

Serra da Malagueta mountains on Santiago Island, Cabo Verde (© Samuel Borges Photography/Shutterstock)

Tawny frogmouth chick, Australia (© SnapRapid/Offset by Shutterstock)

Kazem Dashi rock formation in Lake Urmia, Iran (© Ali/Adobe Stock)

The Appalachian Trail in Stokes State Forest, New Jersey (© Frank DeBonis/Getty Images)

Ortygia, a small island off the coast of Syracuse, Sicily, Italy (© DaLiu/Shutterstock)

Milky Way over the Tagus river in Monfragüe National Park, Spain (© Miguel Angel Muñoz Ruiz/Cavan Images)

Spiral aloe (© David Madison/Getty Images)

A stone wheel engraved in the walls of the Konarak Sun Temple in Orissa, India (© JeremyRichards/Getty Images)

Moose crossing a pond below Mount Moran, Grand Teton National Park, Wyoming (© Jim Stamates/Minden Pictures)

Blacktip reef sharks off the coast of Tahiti, French Polynesia (© Paul Mckenzie/Minden Pictures)

Boats float by rice fields on the Ngo Dong River in Ninh Binh province, Vietnam (© Jeremy Woodhouse/Getty Images)

Mont Choisy Beach, Mauritius (© Robert Harding World Imagery/Offset by Shutterstock)

A Loepa oberthuri moth (© Robert Thompson/Minden Pictures)

Colourful alleyway in the medina of Tétouan, Morocco (© Jan Wlodarczyk/eStock Photo)

Composite image of the moon (© Prathamesh Jaju)

Ruins of Shettihalli Rosary Church in Karnataka, India (© Amith Nag Photography/Getty Images)

The Minokake-Iwa rocks off the coast of the Izu Peninsula, Japan (© Krzysztof Baranowski/Getty Images)

Tokyo Tower in Minato City, Tokyo, Japan (© Yukinori Hasumi/Getty Images)

The ruins of Nalanda Mahavihara in Bihar, India (© Panoglobe/Shutterstock)

'Field of Light' by artist Bruce Munro at Uluru, Australia (© Sheralee Stoll/Alamy)

Mangrove trees, Walakiri Beach, Sumba Island, Indonesia (© Tengguo Wu/Getty Images)

Adler Planetarium near Lake Michigan, Chicago, Illinois (© Amazing Aerial Agency/Offset by Shutterstock)

School of sea goldies in a coral reef with feather stars, Great Barrier Reef, Queensland, Australia (© Gary Bell/Minden Pictures)

Tiger camouflaged amongst tall grass, Assam, India (© Sandesh Kadur/Minden Pictures)

Otter Cliffs, Acadia National Park, Maine (© dbimages/Alamy)

Otter Cliffs, Acadia National Park, Maine, USA (© dbimages/Alamy)

Barley field in East Lothian, Scotland (© Scott Masterton/plainpicture)