St Mary's Cathedral is illuminated as part of a Christmas lights display in celebration of Christmas on December 19, 2014 in Sydney, Australia. (Photo by Brendon Thorne/Getty Images)

Light sculptures glow in the dark at the zoo in Cologne, Germany, 04 December 2019. The artworks are on display at the zoo as part of the China Light Festival that runs until 09 January 2020 and features more than 70 light installations on the zoo grounds. (Photo by Sascha Steinbach/EPA/EFE)

In this photo taken Wednesday, March 8, 2017, a hospitality staff member pose for photos near the shadow of a tall light pole near the Great Hall of the People where a plenary session of the National People's Congress is held in Beijing, China. (Photo by Ng Han Guan/AP Photo)

A participant plays a game on her phone as others watch during a break in a traditional Chinese opera competition at the National Academy of Chinese Theatre Arts in Beijing, China, November 26, 2016. (Photo by Thomas Peter/Reuters)

Folk artist Han Xiaoming demonstrates painting with his tongue in Hangzhou, Zhejiang province December 4, 2014. Han dips his tongue in ink to paint on paper, and uses his fingers to fill in final adjustments. The artist also uses a paintbrush held with his mouth and utilizes fish and vegetables as paint tools, local media reported. (Photo by Aly Song/Reuters)

The UK VELUX Lovers of Light competition attracted 15,000 entries from amateur, professional and mobile phone photographers. Entrants were asked to create a landscape image which celebrates and captures daylight. The judges have whittled these down to a shortlist of ten finalists. The winner will be announced at the end of march with the snapper of the best shot winning a trip to Norway – which will be made during the summer period when the country experiences 24 hour daylight. Photo: “Carousel in the mist”; Prokoshko, Bosnia. (Photo by Marko Stamatovic/PA Wire)

A model showcases lingerie during a lingerie show on International Women's Day at a shopping mall on March 8, 2011 in Qingdao, Shandong Province of China. The official theme of International Women's Day 2011 is “Equal access to education, training and science and technology: Pathway to decent work for women”. (Photo by ChinaFotoPress/Getty Images). QINGDAO, CHINA – MARCH 08 2011

A one-month-old wolf cub ululate as zookeeper Luo Yong plays guitar at the Chongqing Yongchuan Safari Park on March 27, 2008 in Chongqing, China. Luo has worked as a keeper in the wolf zone of the park after he graduated university. Luo has developed a special way to communicate with the wolves by trying to imitate the noises they make. He also teaches wolf cubs to ululate and some wolves will howl along when he plays guitar. (Photo by China Photos/Getty Images)