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)

Two women in traditional kimonos wear face masks to help curb the spread of the coronavirus as they visit the Sensoji temple in Tokyo on Friday, August 7, 2020. (Photo by Hiro Komae/AP Photo)

Enthusiasts participate in the historical re-enactment of the Sevastopol Fortress assault, which took place during the Crimean War of 1853-1856, at a military historical festival in Sevastopol, Crimea, September 5, 2020. (Photo by Alexey Pavlishak/Reuters)

People without face masks are seen at Times Square during the coronavirus disease (COVID-19) pandemic in New York City, U.S., March 11, 2021. (Photo by Eduardo Munoz/Reuters)

Nepali members of the LGBT community take part in a Gay Pride parade in Kathmandu on August 8, 2017. Scores of gays, lesbians, transvestites and transsexuals from across the country took part in the rally to spread their campaign for sexual rights in the country. In 2013 Nepal introduced citizenships with a third gender option and began issuing passports reflecting the same in 2015. (Photo by Prakash Mathema/AFP Photo)

A Somali fisherman carries a sailfish on his head to the Hamarweyne fish market near the port in Mogadishu, Somalia, on January, 5, 2018. (Photo by Mohamed Abdiwahab/AFP Photo)

People take part in a gay pride parade in Warsaw, Poland, on Saturday, June 8, 2019. The Equality Parade is the largest gay pride parade in central and Eastern Europe. It brought thousands of people to the streets of Warsaw at a time when the LGBT rights movement in Poland is targeted by hate speeches and a government campaign depicting it as a threat to families and society. (Photo by Czarek Sokolowski/AP Photo)

Demonstrators protest against bullfighting in front of the City Hall a day before of the famous San Fermin festival, in Pamplona, northern Spain, Friday, July 5, 2019. The festival will begin on July 6 with the “txupinazo” opening ceremony, with people participating in bull runs, music and dance, through the old city. (Photo by Alvaro Barrientos/AP Photo)