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)

A racegoers walks into a rubbish bin following 2016 Melbourne Cup Day at Flemington Racecourse on November 1, 2016 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images)

Model Adriana Lima attends the 19th Annual amfAR New York Gala at Cipriani Wall Street on February 8, 2017 in New York City. (Photo by Splash News and Pictures)

Catholic pilgrim Matilde Madalena de Jesus crawls on a rocky trail carrying a bottle of water on her head during the annual pilgrimage of the dead (Romaria dos Finados), in the city of Juazeiro do Norte, Ceara state, in Brazil October 31, 2016. (Photo by Ueslei Marcelino/Reuters)

A person walks by an Ocean Rebellion activist taking part in a demonstration outside Department for Environment, Food and Rural Affairs (DEFRA) in London, Britain on September 15, 2021. (Photo by Hannah McKay/Reuters)

The Angel of The North at Gateshead in Tyne and Wear, UK with a halo drawn in sky using a light on a drone, captured during a 25-second exposure on January 20, 2025. (Photo by Ian Sproat/Picture Exclusive)

A wax figure depicting Jennifer Lopez by wax museum Madame Tussauds dressed in a new set of clothes attracts the attention of pedestrians during a press event at a beach bar in Berlin,†Germany, August 21, 2015. (Photo by Jens Kalaene/EPA)

Parade-goers walk in the annual West Indian Day Parade on September 02, 2019 in the Brooklyn borough of New York City. The annual celebration of Caribbean culture is one of the largest of its kind and features dozens of floats and costumed participants that make their way down Flatbush Avenue. (Photo by Yana Paskova/Getty Images)