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)

These timeless postcards offer an eye-opening glimpse into life in Japan in the early 20th century. Taken from hand-colored photographs, the postcards showcase the still beauty of the country, depicting a nation on the cusp of modernization. The images feature solemn fishermen, bustling streets, temples and shrines: a country yet to be influenced by Western culture. The tinting effect brings out the rich colors of the natural surroundings, with trees, flowers and cherry blossoms jumping from the original black-and-white images. Here: Toyokuni Shrine Nakanoshima, Osaka, Japan. (Photo by New York Public Library/Caters News)

Supporter Mette Peluce, 11, waits for U.S. Democratic presidential candidate Bernie Sanders to speak in East Los Angeles, California, U.S. May 23, 2016. (Photo by Lucy Nicholson/Reuters)

Seehund “Bruno” looks out of his transport box before making his way to the water on the beach of the island of Juist, Germany on August 14, 2013. Four young seals were released after six weeks of recovery at a rescue station in Norden-Norddeich. (Photo by Carmen Jaspersen/AFP Photo/DPA)

These little grizzly bear cubs had fun making a real splash when their mum took them for a dip to learn how to fish. Kamchatka, Russia. (Photo by Marco Mattiussi/Solent News & Photo Agency)

Employees of a food stand take pictures of Titan, a robot created by England Cyberstein Robots, performing at the Danilovsly market in downtown of Moscow, Russia, 12 May 2014. Titan visited to Moscow to attend “Bal Robotov”, an interactive exhibition of the most recent advances in robotics which will be opened on 15 May in Artplay Moscow exhibition center. Titan worked alongside superstars including Will.i.am, Rihanna, Will Smith and Jackie Chan. (Photo by Sergei Ilnitsky/EPA)

People look at a loaded truck that got stuck in a sinkhole on a road in Guilin, Guangxi Zhuang Autonomous Region, January 7, 2015. No injury was reported, according to local media. (Photo by Reuters/Stringer)

Belarussians in costumes sing songs during the traditional rite of Shchadrets (Schedry vecher or Generous Eve) in the village of Osovo, some 190 km from Minsk, Belarus, 13 January 2015. Shchadrets is a Belarusian folk holiday celebrated on the New Year's Eve in accordance with the Julian calendar (Old New Year). The holiday is similar to Koliady, when youth in costumes walk from house to house singing holiday songs, performing, and asking for a reward afterwards. (Photo by Tatyana Zenkovich/EPA)