Two men standing on a high catwalk, surveying the construction of the Brooklyn Bridge, with Manhattan in the background, New York City, 1877. (Photo by Museum of the City of New York/Archive Photos/Getty Images)

Sunrise over Maridalsvannet in the forest areas near the outskirts of Oslo, the capital of Norway. Winter is approaching, the first snow covers the ground, and the water has already got a thin layer of ice. The temperature is significantly below the freezing point, the air is clear and the sun colors the morning clouds in deep tones. (Photo by Tore-Thiis-Fjeld/Getty Images)

Shortlisted. Dragonfly, North York Moors national park, by Jonathan Green: “In June I was at May Beck with some colleagues when someone spotted this Hawker perched in a gorse bush. I love the detail on the wings, and it’s rare to be able to get so much of such a small subject in clear focus. Getting a few scratches was worth it”. (Photo by Jonathan Green/2020 UK National Parks Photography Competition)

Aurora Borealis, or Northern Lights, shine over the plane wreck of a US Navy airplane – a Douglas Super DC-3 – on the Black Beach in Solheimasandur, south Iceland on January 18, 2018. (Photo by Owen Humphreys/PA Images via Getty Images)

The Grevy’s Illusion by Yaron Schmid, USA: a Grevy’s zebra staring at the camera in Lewa, Kenya. Third place – wildlife. (Photo by Yaron Schmid/The Nature Conservancy Global Photo Contest 2019)

The bare feet of a devotee are pictured as she takes a dip at the Bagmati River during the “Bol Bom” (Say Shiva) pilgrimage in Kathmandu July 21, 2014. The faithful, chanting the name of Lord Shiva, run about 15 km (9 miles) barefooted toward Pashupatinath temple seeking good health, wealth and happiness. (Photo by Navesh Chitrakar/Reuters)

On the western side of Mount Hood lies the longest glacier cave system in the contiguous United States. In 2012, these caves were mapped to a combined length of 7,166.8 feet by cave explorers Brent McGregor and Eddy Cartaya. Currently, the total passage length is hundreds of feet less. Glaciers are frozen rivers; they are always moving and changing... (Photo and caption by Josh Hydeman)