“Catch of the Decade”. Can you guess what happened next? Photo location: Katmai National Park, Alaska, USA. (Photo and caption by Aaron Baggenstos/National Geographic Photo Contest)

These beautiful shots may look like works of modern art – but they are actually close-ups of chemical reactions. The works were snapped with the help of a group of scientists from the University of Science and Technology of China (USTC) in Anhui, China. Here: Zinc reacting with lead nitrate in a soft gel to form lead crystals. (Photo by Yan Liang/Caters News)

North Korean leader Kim Jong Un (front) stands on the conning tower of a submarine during his inspection of the Korean People's Army (KPA) Naval Unit 167 in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang June 16, 2014. (Photo by Reuters/KCNA)

A farrier attaches a horse shoe still hot from the furnace at The Household Cavalry Mounted Regiment (HCMR) at Hyde Park Barracks on March 28, 2012 in London, England. (Photo by Peter Macdiarmid/Getty Images)

Actress/Singer Victoria Justice arrives at the 2012 Teen Choice Awards at Gibson Amphitheatre on July 22, 2012 in Universal City, California. (Photo by Jeffrey Mayer)

A pug dressed as Yoda from the movie Star Wars walks along the runway at the 9th Annual Pug Parade on February 25, 2006 in Bradenton, Florida. 117 pugs competed for 10 prizes in 6 categories. Proceeds from the event benefit the Sarasota County Humane Society. (Photo by Phillippe Diederich/Getty Images)

Groupama Sailing Team, skippered by Franck Cammas of France during leg 1 of the Volvo Ocean Race to Cape Town on November 6, 2011. (Photo by Yann Riou/Groupama Sailing Team/Volvo Ocean Race via Getty Images)