Yerevan residents celebrate Armenian Prime Minister's Serzh Sargsyan's resignation in Yerevan, Armenia, Monday, April 23, 2018. Sargsyan resigned unexpectedly on Monday, an apparent move to bring to an end massive anti-government protests. (Photo by Amos Chapple/RFE/RL)

Vietnam’s Son Doong cave, the largest in the world, could hold a 40-story skyscraper inside. The pristine ecosystem has its own river and jungle. Despite its size, Son Doong wasn’t discovered until 1991. It was lost again for nearly two decades and was fully explored for the first time in 2009. (Photo by Jason Speth/HuffPost)

In this image taken with a slow shutter speed, Spain's tennis player Rafael Nadal gestures during a training session at the Martin Carpena Sports Hall, in Malaga, southern Spain, on Friday, November 15, 2024. (Photo by Manu Fernandez/AP Photo)

Motocross riders compete on the beach on October 15, 2023 in Weymouth, United Kingdom. The motocross event, which first came to the town in 1984, organised by Weymouth and Portland Lions Club in association with Purbeck Motocross Club, sees over 300 riders compete over a course along Weymouth beach. (Photo by Graham Hunt/BNPS)

Canada's Deanna Stellato-Dudek and Maxime Deschamps compete in the pairs short program during the ISU Grand Prix of Figure Skating Final in Beijing on December 7, 2023. (Photo by Tingshu Wang/Reuters)

“Gangnam Style” star PSY's new music video had been watched more than 10 million times on YouTube less than 24 hours after he unveiled his much-anticipated new dance in Seoul, the website showed Sunday. Photo: PSY performs at his concert “Happening” in Seoul, on April 13, 2013. The South Korean pop star's first new single since his viral hit “Gangnam Style” is stealing attention from inter-Korean tensions. (Photo by Kin Cheung/Associated Press)

This is a portion of the first color 360-degree panorama from NASA's Curiosity rover, made up of thumbnails, which are small copies of higher-resolution images. The mission's destination, a mountain at the center of Gale Crater called Mount Sharp, can be seen in the distance, to the left, beginning to rise up. The mountain's summit will be imaged later. (Photo by NASA/JPL-Caltech/MSSS)