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 woman works in a rubber plantation in Yala province, southern Thailand, January 30, 2017. Thai rubber exporters say they have enough of the commodity in stockpiles to ensure only minimal disruption to scheduled shipments in the wake of deadly floods in key growing regions. (Photo by Surapan Boonthanom/Reuters)

Competitors climb in front of the Matterhorn mountain at the start of the 21st Glacier Patrol race in Stafel outside the ski resort of Zermatt, Switzerland, 18 April 2018. The Glacier Patrol (Patrouille des Glaciers in French), organized by the Swiss Army, takes place from April 17 to 21. Highly-experienced hiker-skiers trek for over 53km (3994m ascent and 4090m descent) along the Haute Route along the Swiss-Italian border from Zermatt to Verbier. (Photo by Valentin Flauraud/EPA/EFE)

Kritchaya “Lolita” Boonhor (R) curls her eyelashes in ladyboy Candy's (L) room while she chats her about her boyfriend, in Bangkok, Thailand, 27 November 2017. Most things in life are a question of negotiation. Lolita is a woman, that was not to be negotiated. What needed to be negotiated was how she was perceived by those around her. And that negotiation was one that took time and effort. (Photo by Lola Levan/EPA/EFE)

A glamour model Lacey Banghard attends a photocall for PETA to encourage pet owners to have their cats and dogs sterilised at Picadilly Circus on January 22, 2013 in London, England. (Photo by Ben Pruchnie)

“The most serious health problem in the U.S. today is obesity.” Sounds familiar, doesn’t it? But that pronouncement about obesity’s primacy in the hierarchy of national health problems is not new. Rather, it’s the opening line to a remarkable article published 60 years ago in LIFE magazine. This photographs made by Martha Holmes to illustrate that March 1954 article, titled “The Plague of Overweight.” Photo: Dorothy Bradley (left), photographed for LIFE magazine article on obesity, 1949. (Photo by Martha Holmes/Time & Life Pictures)

The 33-year-old Norwegian rightwing extremist Anders Behring Breivik, who killed 77 people in twin attacks in Norway last year, arrives at a courtroom. (Photo by Heiko Junge/AP File Photo)