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)

The Y-40 Deep Joy is the worlds deepest pool. Y-40 is projected by Architect Emanuele Boaretto and supported by the “Boaretto Group Hotel and Resort”. The name Y-40 is inspired by mathematical symbols. “Y” is the ordinate axis of the Cartesian system and “–40” means the world's record depth or our pool- that is 40 meters underground. (Photo by Courtesy Y40 Deep Joy)

Julya Baer, 30, attends a candlelight vigil and celebration of Prince's life in Leimert Park in memory of musician Prince on April 21, 2016, in Los Angeles, California. Prince died earlier today at his Paisley Park compound at the age of 57. (Photo by Kevork Djansezian/Getty Images)

Ukrainian emergency workers spray a plane with water hoses as part of a rescue training exercise at Boryspil International Airport outside Kiev, Ukraine, September 27, 2016. (Photo by Valentyn Ogirenko/Reuters)

Crowds on the beach in Cape Canaveral, Fla., watch the launch of the SpaceX Falcon 9 Crew Dragon on its Crew-1 mission carrying four astronauts, Sunday, November 15, 2020, in this 3 1/2-minute time exposure. The rocket was launched from Launch Complex 39A at Kennedy Space Center at 7:27 p.m. Sunday evening. (Photo by Malcolm Denemark/Florida Today via AP Photo)

Kylian Mbappe of France looks dejected on the bench after a penalty shoot out loss during the FIFA World Cup Qatar 2022 Final match between Argentina and France at Lusail Stadium on December 18, 2022 in Lusail City, Qatar. (Photo by Carl Recine/Reuters)

A cheerleader jumps for joy before the start of the Pan-Am Games in Santiago, Chile on October 31, 2023. Thousands of athletes from across the Americas are competing before the Paris Games next year. The International Olympic Committee recognised cheerleading as an Olympic sport in 2021. (Photo by Dylan Martinez/Reuters)

An eight-week-old sea otter rescued from Seldovia, Alaska, peaks out of his enclosure at Shedd Aquarium Wednesday, December 6, 2023, in Chicago. The otter was found alone and malnourished and was taken to the Alaska SeaLife Center in Seward, Alaska, which contacted Shedd, and the Chicago aquarium was able to take the otter in. He will remain quarantined for a few months while he learns to groom and eat solid foods before being introduced to Shedd's five other sea otters. (Photo by Erin Hooley/AP Photo)