A vendor (C) cuts slaughtered dogs for sale at his roadside stall in Duong Noi village, outside Hanoi December 16, 2011. While animal rights activists have condemned eating dog meat as cruel treatment of the animals, it is still an accepted popular delicacy for some Vietnamese, as well in some other Asian countries. Duong Noi is well-known as a dog-meat village, where hundreds of dogs are killed each day for sale as popular traditional food. Dog-eating as a custom is rooted in Vietnam and was developed as a result of poverty. One kilogram of dog meat costs about 130,000 dongs ($6.2). (Photo by Reuters/Kham)

Mount Sinabung looks calm as seen from Karo, North Sumatra at dawn on August 8, 2021. (Photo by Tibta Nangin/AFP Photo)

MTV “Ex On The Beach” star Charlotte Dawson and Big Brother star Sam Giffen (not pictured) having fun on a night out in Manchester, England after leaving neighbourhood restaurant on September 8, 2016. (Photo by XposurePhotos.com)

Young man making the O.K. sign. (Photo by George Marks/Retrofile/Getty Images). Circa 1950s

(L-R) Shiri Appleby and Kevin Zegers of “What Just Happened??! with Fred Savage” attend the Pizza Hut Lounge at 2019 Comic-Con International: San Diego on July 19, 2019 in San Diego, California. (Photo by Presley Ann/Getty Images for Pizza Hut)

A performer wearing a face shield looks on during a ceremony held by the Bangkok National Museum to celebrate the return of two ancient relics, believed to have been stolen from Thailand about 60 years ago, from the United States, in Bangkok, Thailand on May 31, 2021. (Photo by Soe Zeya Tun/Reuters)

Luis Hernan was always curious about how wireless technologies like radio are transmitted through the air. So after finishing up his studies in architecture, computer science, and design, Hernan decided to research these invisible signals through a PhD at Newcastle University. Hernan set up a system that turned the wireless signals around him into colourful, ghostlike images using long-exposure photography, allowing people to see the strength of the signals around them. (Photo by Luis Hernan)