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 worker inspects unfinished firecrackers as they make pyrotechnics at a makeshift factory in Bocaue town, Bulacan province, north of Manila December 27, 2014. Firecracker makers in Bulacan province, the pyrotechnic capital of the Philippines, are in haste to meet the demands for the coming New Year revelry. (Photo by Romeo Ranoco/Reuters)

A woman runs while another woman ducks down to avoid teargas as police disperse supporters of the opposition Coalition for Reforms and Democracy (CORD), led by former Prime Minister Raila Odinga, during a demonstration against Independent Electoral and Boundaries Commission (IEBC) in downtown Nairobi, Kenya, 09 May 2016. (Photo by Dai Kurokawa/EPA)

Supporters of the PHTK presidential candidate Jovenel Moise strike zombie poses during a protest march demanding the resignation of interim President Jocelerme Privert in Port-au-Prince, Haiti, Tuesday, June 7, 2016. The electoral council of Haiti has decided to re-do a presidential election that a special commission determined was marred by fraud. (Photo by Dieu Nalio Chery/AP Photo)

A soldier of the Household Cavalry Mounted Regiment falls off a horse during a practice to participate in the state ceremonial surrounding this year's Platinum Jubilee celebrations at Hyde Park in London, Thursday, March 31, 2022. Around 170 horses and personnel of the Household Cavalry Mounted Regiment left their Hyde Park Barracks to form up and be inspected by the General Officer Commanding the Household Division, Major General Christopher Ghika. (Photo by Frank Augstein/AP Photo)

Ukrainian army soldier Dasha, 22, checks her phone after a military sweep to search for possible remnants of Russian troops after their withdrawal from villages in the outskirts of Kyiv, Ukraine, Friday, April 1, 2022. (Photo by Rodrigo Abd/AP Photo)

Tourists ice skate at night on the Eiffel Tower's skating rink in Paris December 9, 2014. The skating rink, located on the first level of the Eiffel Tower, opens to the public as part of the Christmas holiday season. (Photo by Charles Platiau/Reuters)

A visitor takes a picture of goldfish at the Art Aquarium exhibition in Tokyo Friday, August 12, 2016. The exhibition, featuring around 8,000 goldfish in tanks themed on Japan's Edo Period. (Photo by Koji Sasahara/AP Photo)