Muniellos Nature Reserve in Asturias, Spain

Inscription Wall at the Martin Luther King Jr. Memorial in Washington, DC

Aura River in Turku, Finland

Domestic donkey feeding on cherry twigs

Giant kelp in the Channel Islands National Marine Sanctuary, California

Rumelihisarı on the Bosporus Strait at Istanbul, Türkiye

'Umschreibung,' a sculpture by artist Olafur Eliasson in Munich, Germany

Hummock ice on Lake Peipus in Estonia

Bison in Wind Cave National Park, South Dakota

Breckenridge, Colorado

Wool and mohair yarn

Black Fell, Lake District, England

Harbin International Ice and Snow Sculpture Festival, Harbin, China

Earth as seen from the International Space Station

Sandhill cranes, Bosque del Apache National Wildlife Refuge, New Mexico

Hohenzollern Castle, Germany

Polar bear in Svalbard, Norway

New Year's Eve fireworks, Sydney Harbour Bridge, Australia

Rock formations in the White Desert, Egypt

A pair of silver-studded blue butterflies