Reykjavik on the second night of the Yule Lads (© Arctic-Images/Corbis Documentary/Getty Images)(Bing United States)

Reykjavik on the second night of the Yule Lads (© Arctic-Images/Corbis Documentary/Getty Images)(Bing United States)

Poinsettia flower buds (© Wild Wonders of Europe/Radisics/Minden Pictures)(Bing United States)

Poinsettia flower buds (© Wild Wonders of Europe/Radisics/Minden Pictures)(Bing United States)

Mount Kilimanjaro seen from Chyulu Hills National Park in Kenya for Mountain Day (© Lucas Vallecillos/Alamy Stock Photo)(Bing United States)

Mount Kilimanjaro seen from Chyulu Hills National Park in Kenya for Mountain Day (© Lucas Vallecillos/Alamy Stock Photo)(Bing United States)

A Christmas Island red crab during its migration (© Ingo Arndt/Minden Pictures)(Bing United States)

A Christmas Island red crab during its migration (© Ingo Arndt/Minden Pictures)(Bing United States)

Snow covering the Painted Hills of John Day Fossil Beds National Monument in Oregon (© Floris van Breugel/Minden Pictures)(Bing United States)

Snow covering the Painted Hills of John Day Fossil Beds National Monument in Oregon (© Floris van Breugel/Minden Pictures)(Bing United States)

Two Jack Lake in Banff National Park, Alberta, Canada (© Aurora Photos/Offset by Shutterstock)(Bing United States)

Two Jack Lake in Banff National Park, Alberta, Canada (© Aurora Photos/Offset by Shutterstock)(Bing United States)

The USS Arizona Memorial at Pearl Harbor, Honolulu, Hawaii (© AB Forces News Collection/Alamy Stock Photo)(Bing United States)

The USS Arizona Memorial at Pearl Harbor, Honolulu, Hawaii (© AB Forces News Collection/Alamy Stock Photo)(Bing United States)

An eagle-owl in Helsinki for Finland's Independence Day (© Markus Varesvuo/Minden Pictures)(Bing United States)

An eagle-owl in Helsinki for Finland's Independence Day (© Markus Varesvuo/Minden Pictures)(Bing United States)

An eagle-owl in Helsinki for Finland's Independence Day (© Markus Varesvuo/Minden Pictures)(Bing United States)

An eagle-owl in Helsinki for Finland's Independence Day (© Markus Varesvuo/Minden Pictures)(Bing United States)

The US Capitol with flags at half-staff as former President George H.W. Bush lies in state at the Capitol rotunda, Washington, DC, on Dec 3, 2018 (© Al Drago/Bloomberg via Getty Images)(Bing United States)

The US Capitol with flags at half-staff as former President George H.W. Bush lies in state at the Capitol rotunda, Washington, DC, on Dec 3, 2018 (© Al Drago/Bloomberg via Getty Images)(Bing United States)

The US Capitol with flags at half-staff as former President George H.W. Bush lies in state at the Capitol rotunda, Washington, DC, on Dec 3, 2018 (© Al Drago/Bloomberg via Getty Images)(Bing United States)

The US Capitol with flags at half-staff as former President George H.W. Bush lies in state at the Capitol rotunda, Washington, DC, on Dec 3, 2018 (© Al Drago/Bloomberg via Getty Images)(Bing United States)

Sphinx Observatory in Switzerland (© Jan Greune/Alamy)(Bing United States)

Sphinx Observatory in Switzerland (© Jan Greune/Alamy)(Bing United States)

Sphinx Observatory in Switzerland (© Jan Greune/Alamy)(Bing United States)

Sphinx Observatory in Switzerland (© Jan Greune/Alamy)(Bing United States)

A page of Alan Turing's notebook to kick off Computer Science Education Week (© Spencer Platt/Getty Images News)(Bing United States)

A page of Alan Turing's notebook to kick off Computer Science Education Week (© Spencer Platt/Getty Images News)(Bing United States)

Old Nuuk in Nuuk, Greenland (© nevereverro/Getty Images)(Bing United States)

Old Nuuk in Nuuk, Greenland (© nevereverro/Getty Images)(Bing United States)

Old Nuuk in Nuuk, Greenland (© nevereverro/Getty Images)(Bing United States)

Old Nuuk in Nuuk, Greenland (© nevereverro/Getty Images)(Bing United States)

A view of our southernmost continent for Antarctica Day (© Jan Vermeer/Minden Pictures)(Bing United States)

A view of our southernmost continent for Antarctica Day (© Jan Vermeer/Minden Pictures)(Bing United States)

A view of our southernmost continent for Antarctica Day (© Jan Vermeer/Minden Pictures)(Bing United States)

A view of our southernmost continent for Antarctica Day (© Jan Vermeer/Minden Pictures)(Bing United States)