South Korean college students wearing masks hold up candles as they march after a rally calling for South Korean President Park Geun-hye to step down in Seoul, South Korea, Saturday, November 12, 2016. Hundreds of thousands of people flooded Seoul's streets on Saturday demanding the resignation of Park amid an explosive political scandal, in what may be South Korea's largest protest since it shook off dictatorship three decades ago. (Photo by Lee Jin-man/AP Photo)

A mother prays for success for her child in the college entrance examinations at a Buddhist temple in Seoul, South Korea, November 12, 2015. About 630,000 students on Thursday sat for the annual exams that could lead them to one of the country's top universities. In South Korea, there is no higher achievement than to be accepted by a prestigious university. As a result, many students prepare for these entrance exams from an early age, often studying up to 16 hours a day for years to take this test. (Photo by Kim Hong-Ji/Reuters)

KARA perform on stage during their first solo concert KARASIA at Olympic gymnasium on February 18, 2012 in Seoul, South Korea. (Photo by Chung Sung-Jun/Getty Images)

A guard secures gates of a catfish farm visited by a group of foreign reporters in Pyongyang, North Korea April 17, 2017. (Photo by Damir Sagolj/Reuters)

South Korean football fans react during a public screening in Seoul of the South Korea vs Russia football match at the 2014 World Cup in Brazil, early on June 18, 2014. (Photo by Ed Jones/AFP Photo)

Chinese tourists make a toast with canned drinks and fried chicken pieces during an event organized by a Chinese company at a park in Incheon, South Korea, March 28, 2016. (Photo by Kim Hong-Ji/Reuters)

These are the dunes of the Namib Desert, taken by Korea's Kompstat-2 satellite. The blue and white area is the dried riverbed of the Tsauchab river. (Photo by The European Space Agency)