Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

In this May 12, 2017 photo, Pupy, an African elephant, stands in the doorway of his enclosure at the former city zoo now known as Eco Parque in Buenos Aires, Argentina. A year ago the 140-year old Buenos Aires zoo closed its doors and was transformed into a park. The first director decided that the animals should be housed in buildings that reflected their countries of origin. A replica of a Hindu temple was built for the Asian elephants. (Photo by Natacha Pisarenko/AP Photo)

Lukas Irmler balances on a 800 meter long highline 200 meters above Segnesboden, on Friday, June 28, 2019, in Flims, Switzerland. The highline is Switzerland's longest and will be set up untill Sunday in the Sardona World Heritage Region. (Photo by Gian Ehrenzeller/Keystone via AP Photo)

This beautiful set of images capture the moment a young ballet dancer interacts with her four-legged friends against some iconic backdrops including the Church of the Savior on Blood and the Admiralty building in Saint Petersburg. The enchanted photos were taken by Andrey Seliverstov, 59 from Saint Petersburg, Russia. Here: Nine year old Maria Palkina dancing with dogs. (Photo by Andrey Seliverstov/Caters News Agency)

A man drives a car loaded with electronic and household appliances the Dbayeh highway, at the northern entrance of Lebanon's capital Beirut, on August 11, 2020, following a huge chemical explosion that devastated large parts of the city. (Photo by Joseph Eid/AFP Photo)

A biker carrying huge bags of recyclables travels on a street outside Phnom Penh, Cambodia on Saturday, March 27, 2021. (Photo by Heng Sinith/AP Photo)

Astronauts Harrison Schmitt (left) and Eugene Andrew Cernan practice taking geological samples at the Kennedy Space Center in Florida, in preparation for NASA's scheduled Apollo 17 lunar landing mission, on August 28, 1972. Schmitt is the Lunar Module Pilot and Cernan is the mission's Commander. They are training for their period of EVA (extravehicular activity) on the Moon. (Photo by Space Frontiers/Getty Images)