Hooded demonstrators vandalise a shop window in Mexico City, during the commemoration of the 50th anniversary of the 1968 Tlatelolco student massacre, on October 2, 2018. Fifty years ago, Mexican troops opened fire on student demonstrators, killing hundreds just days before Mexico City hosted the 1968 Olympics – one of the darkest episodes in a year of global turbulence. (Photo by Ronaldo Schemidt/AFP Photo)

Kimono-clad women enjoy the view from Tokyo Sky Tree’s 350-meter-high observation deck in Sumida Ward, Tokyo, on the Coming of Age Day, January 9, 2017. Sumida Ward invited about 430 local 20-year-old to the deck to celebrate them. Many city governments invite local 20-years-old to there’s symbolic places and celebrate for their Coming of Age Day. (Photo by The Yomiuri Shimbun via AP Images)

5-year-old Chinese girl Wang Anna prepares meals for her grandmother and great-grandmother at home in Zhuyuan village, Guizhou province, China on March 3, 2017. Chinese girl called Wang Anna, 5, takes care of her ill grandmother and 92-year-old great-grandmother on her own every day in a mountainous village in Zhima town, Zunyi city, southwest China's Guizhou province. Her father went to jail before she was born and her mother remarried after gave birth to her. Although she is just five years old, she started to shoulder the responsibility to look after ill grandmother and elderly great-grandmother. (Photo by Imaginechina/Rex Features/Shutterstock)

Isabel Schmalenbach, an environmental scientist with the Helgoland Biological Institute (Biologische Anstalt Helgoland), part of the Alfred Wegener Institute for Polar and Marine Research, holds a one-year old baby European lobster (Homarus gammarus) raised at the institute on August 3, 2013 on Helgoland Island, Germany. Later in the day Schmalenbach and her colleagues released a total of 415 one-year old lobsters into the North Sea as part of an effort to repopulate the lobster population around Helgoland (also called Heligoland). In the 19th century local fishermen caught up to 80,000 lobsters a year in the surrounding waters, combined with the heavy allied bombing of the island during and after World War II, as well as other environmental factors, decimated the lobster population. (Photo by Sean Gallup)

This composite image shows a sequence, from bottom left to top left, of the moon's transition during a total lunar eclipse on April 15, 2014 in Miami, Florida. People in most of north and south America should be able to witness this year's first total lunar eclipse, which will cause a “blood moon” and is the first of four in a rare Tetrad of eclipses over the next two years. (Photo by Joe Raedle/Getty Images)

Foreign tourists join the annual Songkran Festival celebration, the Thai traditional New Year, also known as the water festival in Silom district of Bangkok, Thailand, 13 April 2014. The three-day Songkran Festival runs from 13 to 15 April and is celebrated with splashing water and putting powder on each others faces as a symbolic sign of cleansing and washing away the sins from the old year. (Photo by Narong Sangnak/EPA)

This July 2014 image provided by the Bureau of Land Management shows the interior of the Natural Trap Cave in north-central Wyoming. The cave holds the remains of tens of thousands of animals, including many now-extinct species, from the late Pleistocene period tens of thousands of years ago. Scientists have resumed digging for the first time in more than 30 years. (Photo by AP Photo/Bureau of Land Management)

Visitors watch as members of a local winter swimmers club pour buckets of cold water over their daughters, 7-year-old Liza Broverman and 2-year-old Alisa Smagina during a celebration of Polar Bear Day at the Royev Ruchey zoo, with the air temperature at about minus 5 degrees Celsius (23 degrees Fahrenheit), in Krasnoyarsk, Russia, November 27, 2016. (Photo by Ilya Naymushin/Reuters)