“Aurora Hunters”. Photographers taking part in a photography tour on the Lofoten Islands in Norway, pull over on the side of the road to take a photo of their first ever Aurora Borealis after spotting it from their tour bus. Photo location: Rystad, Lofoten Islands, Norway. (Photo and caption by Mark Gee/National Geographic Photo Contest)

People watch dragon dance performance in front of a business establishment in celebration of Chinese New Year at Manila's Chinatown district of Binondo, Philippines, Friday, January 31, 2014. (Photo by Bullit Marquez/AP Photo)

Mangli Munda poses on her wedding day with a stray dog in Jharkhand, India on August 30, 2014. An 18-year-old Indian girl has married a stray dog as a part of a tribal ritual designed to ward off an evil spell. Village elders hastily organised the wedding between Mangli Munda and the canine as the teenager is believed to be bringing bad luck to her community in a remote village in Jharkhand state. Mangli's father Sri Amnmunda agreed and even found a stray dog named Sheru as a match for his daughter. And while Mangli was a hesitant bride, she believes that the ceremony will help ensure that her future human husband will have a long life. (Photo by Barcroft Media/ABACAPress)

“Freedom”. After the 30 years banning import large motorcycle, in 2007, the Taiwan government reopened the import licensing of the motorcycle displacement over 550 cubic centimeter. Those large bikes, which were never seen before, were strange thought and treated unequally frequently. However, those adversity will not stop those enthusiastic bike riders from chasing the road of freedom. Photo location: Taiwan. (Photo and caption by 火花 羅/National Geographic Photo Contest)

NYC no pants subway ride. Thousands of straphangers took their pants off for the 15th annual "No Pants Subway Ride" hosted by Improv Everywhere. People gathered at seven meeting points throughout the five boroughs at 3PM. All participants met up at Union Square around 5PM to and had a pant-less celebration and the afterparty at Webster Hall. (Photo by Paul Martinka/The New York Post)

Passengers wear no trousers as they ride the London Underground in London, Britain, 07 January 2018. The No Pants Subway Ride is an global annual event where people take the public transport while they are not wearing trousers to surprise other passengers. This event takes place on the first Sunday of every year in the world's major cities. (Photo by Tolga Akmen/EPA/EFE/Rex Features/Shutterstock)

A woman rides a mini bicycle through crowds of Santa costumes in a park during the annual SantaCon on December 10, 2016 in London, England. The event sees hundreds of people walking the streets of London and drinking alcohol in Father Christmas and other festive costumes. (Photo by PA Wire)

A displaced Iraqi girl, who fled her home, cries during a battle between Iraqi forces and Islamic State militants, near Badush, Iraq, March 16, 2017. (Photo by Reuters/Stringer)