The CBRE Urban Photographer of the Year competition – now in its ninth year – encourages professional and amateur photographers to capture cities at work. Here: Dog Walker – 15:00. The competition allows photographers to enter up to 24 images, one representing each hour of the day. (Photo by Johanna Siegmann)

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)

This series of pictures shot by satellite, show the man-made world as astronauts see it. Artist Benjamin Grant uses Google Earth to find the most compelling satellite images of human civilization. The stunning pictures of sprawling metropolises and vast reservoirs are sometimes unidentifiable until zoomed in. In order to find an extraordinary picture in the practically endless supply of satellite data, Benjamin focuses on the themes of current events or environmental issues. Here: Industrial Sector, Tokai, Japan. (Photo by Benjamin Grant/Digital Globe/Caters News)

Traffic enforcer Ramiro Hinojas, 51, wears a Santa Claus costume while directing motorists through traffic at an intersection in Pasay City, Metro Manila, Philippines on November 28, 2017. (Photo by Romeo Ranoco/Reuters)

These images are enough to make viewers do a double-take. Although they look like vibrant works of abstract art, they are actually drone photographs taken by brothers J.P. and Mike Andrews, from near Wolverhampton, England. Here: Kickflip. (Photo by J.P. Andrews/Mike Andrews/Caters News Agency)

U.S. Secretary of State John Kerry and Mongolian Foreign Minister Lundeg Purevsuren watch an archer during a Naadam ceremony, a competition which traditionally includes horse racing, Mongolian wrestling and archery, in Ulan Bator, Mongolia, June 5, 2016. (Photo by Saul Loeb/Reuters)

Bikini-clad women ski as they are led by a car during a performance on the frozen Yenisei River outside Krasnoyarsk, Siberia, Russia, March 20, 2016. The performance, entitled “Siberian Spring's Strings” and created with the participation of artist Vasily Slonov, marked the day of spring equinox (vernal equinox), according to organizers. (Photo by Ilya Naymushin/Reuters)

A paramilitary police officer (right) turns around as hostesses line up for roll call ahead of the Beijing International Automotive Exhibition in Beijing, China, on Monday, April 25, 2016. Tesla Motors Inc. and BYD Co. are among manufacturers showing 147 new-energy vehicles at this year's show. (Photo by Qilai Shen/Bloomberg)