Explorers on icy shore

1600 × 1200

scientist sampling lava

1200 × 899

William Bartram in a forest

1600 × 1200

Dog sled expedition in snow

1600 × 1200

National Geographic Explorer in Antarctica

1600 × 1000

Penguins swimming under ice

1600 × 1200

Woman in niqab near blue vehicle

1600 × 1200

Albert Einstein sticking out his tongue

2261 × 2933

Statue of Liberty on Liberty Island

1600 × 1200

Danish women's gymnastics team

1280 × 1012

U.S. Coast Guard in Arctic

3008 × 2000

Polar bear on ice floe

1280 × 960

National Geographic Explorer in Antarctica

1600 × 1000

Polarstern ice research vessel

1800 × 1350

Mars map from National Geographic

1600 × 1000

Polar bear near research station

1600 × 1200

Antarctic research station

1600 × 1200

Arctic wolf on ice floe

1600 × 1105

Arctic wolf on ice floe

1280 × 984

Penguin under ice floe

1600 × 1200