Aiden Haas, left, and Lilli Alcala pose after being crowned Mud King and Mud Queen at the 29th annual Mud Day, Tuesday, July 12, 2016 in Westland, Mich. The event, open to children 12 and younger, was at the Hines Park-Nankin Mills Area west of Detroit. Children 12 and younger were able to slosh around in the pit while participating in mud limbo, wheelbarrow races and other free activities. (Photo by Carlos Osorio/AP Photo)

Aeronautics and Space engineer at France's Compagnie Maritime d'Expertises, or Comex, Arnaud Prost (C) meets with a jogger as he tests on the ground the “Gandolfi 2” underwater training suit for spacewalk, on January 20, 2016 in the calanques region (rocky inlets) of Marseille. The underwater training suit “Gandolfi 2”, developed with the European Space Agency (ESA), is designed for training astronauts underwater to simulate space gravity for the astronaut's extravehicular activities (EVAs). (Photo by Boris Horvat/AFP Photo)

World's Greatest Swimming Pools: Four Seasons, Serengeti Pool, Tanzania. A show of elephants, buffalo and baboons awaits thanks to an active watering hole below the free-form infinity pool at this plush hideaway inside Serengeti National Park. Bonus: Because of infrared technology at the hole, guests can be notified on their bedroom TV when animals are approaching. When you've got word of wildlife on the horizon, catch them from your private terrace – or head back to the pool. (From $1,650). (Photo by Four Seasons)

This November 11, 2014 aerial photo, shows a deforested area dotted with blue tarps, marking the area where miners reside, and craters filled with water, caused by illegal gold mining activities, in La Pampa, in Peru's Madre de Dios region. Less than a month before Peru plays host to global climate talks, the government sent a battalion of police into southeastern jungles to dismantle illegal gold-mining mining camps. Peru's anti-illegal mining czar, retired army Gen. Augusto Soto, marched the men to the wasteland known as La Pampa, where 50,000 hectares of rainforest have been obliterated in the past six years. (Photo by Rodrigo Abd/AP Photo)

Toyota revealed its i-Road concept, a three-wheeled all-electric motorcycle of sorts that seats two. The unique design is only 33 inches wide, which would make it tops in buzzing in through and around traffic. An Active Lean system tilts the i-Road through corners like a motorbike, while the cabin (which seats two in a tandem layout) is fully enclosed. Maximum range is about 30 miles. (Photo by Luis Fernando Ramos/G1)

Descending into the Marum Volcano in Vanuatu, Intrepid explorers found an unusual way of staying warm this winter by spending Christmas day on an active volcano. British climber Chris Horsley, 22, and his friends Gareth Hawken, 30, Geoff Mackley, 50, and Bradley Ambrose, 36, from Auckland, New Zealand, hiked up the Marum Volcano, Vanuatu, on the morning of the 25th. Instead of passing the day with their families, the team climbed down a 1200ft cliff to get close to a flowing lake of lava. (Photo by Bradley Ambrose/Caters News)

Lava erupts from a crater of Mt. Etna, Europe's largest active volcano, behind Santa Maria della Guardia church in Belpasso, near Catania, in southern Italian island of Sicily, early Friday, June 18, 2021. Since Feb. 16, 2021, Mt. Etna has begun a series of spectacular eruptive episodes. (Photo by Salvatore Allegra/AP Photo)

People try to catch offerings thrown off the summit of Mount Bromo volcano by Tengger tribe members and local tourists in Probolinggo, East Java province on July 18, 2019, as part of the Yadnya Kasada Festival. During the annual Yadnya Kasada festival, the Tenggerese climb Mount Bromo, an active volcano, and seek the blessing from the main deity by presenting offerings of rice, fruit, livestock and other items. (Photo by Juni Kriswanto/AFP Photo)