Machu Picchu, Peru. A llama’s-eye view of the legendary Inca settlement at Machu Picchu, isolated high in the Peruvian Andes. (Photo by Jim Turner/National Geographic)

Four pillars of light from the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) are shown reaching into the Chilean night sky in this image from ESO Photo Ambassador Fred Kamphues, on September 2, 2016. The lasers are a key part of the adaptive optics system on the VLT. Adaptive optics allows astronomers to drastically reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT. (Photo by F. Kamphues/ESO)

In this Sunday, March 5, 2017, photo, hospitality staff take souvenir photos in front of the Great Hall of the People where the National People's Congress is held in Beijing. (Photo by Andy Wong/AP Photo)

Students training to be flight attendants hold books on their heads, chopsticks in their mouths, and papers in between their knees, as they take part in a standing posture practice at a vocational school in Shijiazhuang, Hebei province, China May 4, 2017. (Photo by Reuters/Stringer)

An adult specimen of Nannospalax (leucodon) montanosyrmiensis, a variant of the lesser mole-rat (Spalax leucodon) is pictured near Albertirsa, some 60 kilometers southeast of Budapest, Hungary, 12 May 2018. The critically endangered rodent lives in several isolated populations in the Carpathian Basin. (Photo by Sandor Ujvari/EPA/EFE)

A model walks the runway during the BLACK TAPE PROJECT show at New York Fashion Week Powered By Art Hearts Fashion at The Angel Orensanz Foundation on September 9, 2018 in New York City. (Photo by Arun Nevader/Getty Images for Art Hearts Fashion)

A cave diver in Anhumas Abyss, Bonito, Brazil. (Photo by Marcio Cabral/Epson International Pano Awards 2018)

Female female male threesome. My bit on the side is my best male friend. (Photo by Laoshi/Getty Images)