A Nepalese devotee bows in front of a cow during the 'Gai Puja', also known as the Cow Worship Day, as part of the Tihar festival in Kathmandu, Nepal, 11 November 2015. The Tihar festival is the second most important event for Nepalese Hindus. During the celebrations people worship cows, considered the incarnation of Lord Laxmi, the god of wealth. (Photo by Narendra Shrestha/EPA)

A diver dressed in a Santa Claus costume performs with sardines at the Coex Aquarium in Seoul, South Korea, Wednesday, December 9, 2015. (Photo by Ahn Young-joon/AP Photo)

A Pomeranian dog is seen during an international dog exhibition in Kannot, central Israel May 21, 2016. Some 850 purebred dogs from about 200 mini breeds participated in the exhibition. (Photo by Amir Cohen/Reuters)

Models present outfits made with air balloons during an international festival of air balloons design in Almaty, Kazakhstan, July 9, 2015. (Photo by Shamil Zhumatov/Reuters)

A Belarussian woman looks in the mirror as she takes part in the festival of national traditions “Piatrovski” in the village of Shipilovichi, south of Minsk, July 12, 2015. (Photo by Vasily Fedosenko/Reuters)

A tourist reacts as an elephant sprays her with water in celebration of the Songkran water festival in Thailand's Ayutthaya province, April 9, 2014. Songkran, the most celebrated festival of the year, marks the start of Thailand's traditional New Year. (Photo by Chaiwat Subprasom/Reuters)

A Tibetan man stirs butter tea made for the arriving guest during the function organised to mark Losar or the Tibetan New Year at a Tibetan Refugee Camp in Lalitpur February 19, 2015. Tibetans across the world marked the arrival of the New Year with prayers and festivities. (Photo by Niranjan Shrestha/AP Photo)

British theoretical physicist Stephen Hawking, Cambridge University Professor and Fellow, circa 1985. Stephen Hawking, the brightest star in the firmament of science, whose insights shaped modern cosmology and inspired global audiences in the millions, has died aged 76. (Photo by Gemma Levine/Getty Images)