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)

Wearing a protective mask to curb the spread of the new coronavirus a man attends a memorial for those who have died from COVID-19 worldwide, at Rio's Christ the Redeemer statue in Rio de Janeiro, Brazil, Wednesday, July 1, 2020. (Photo by Leo Correa/AP Photo)

Kate O'Connor of Team Northern Ireland celebrates during the Women's Heptathlon High Jump on day five of the Birmingham 2022 Commonwealth Games at Alexander Stadium on August 02, 2022 in the Birmingham, England. (Photo by Matthew Lewis/Getty Images)

A Secret Service police officer wrestles a protester to the ground after she ran towards a motorcade on its way to the LA Convention Center where North and South American leaders are gathered for the ninth Summit of the Americas in Los Angeles, June 8, 2022. (Photo by Apu Gomes/AFP Photo)

A baby baboon appears to ride its mother like a horse at the Chobe River, in The Chobe National Park, Botswana, Southern Africa in January 2023. Young monkeys often ride on their parent's backs, like this Chacma baboon, for protection. (Photo by William Steel/Solent News & Photo Agency)

Alice Goodridge (left) and Tanya Mackenzie (right), members of the Loch Insh Dippers wild swim group, take part in a Christmas-themed swim in the frozen Loch Insh, Kingussie, in the Cairngorms National Park, Scotland on Friday, December 13, 2024. (Photo by Jane Barlow/PA Images via Getty Images)

A smiling gecko bursts through a gap in the bark to surprise photographer in West Java, Indonesia in the last decade of March 2025. (Photo by Dzul Duzulfikri/Animal News Agency)

Mario Barrios, left, fights Manny Pacquiao in a welterweight title boxing match Saturday, July 19, 2025, in Las Vegas. (Photo by John Locher/AP Photo)