A Hindu holy man, or sadhu, smokes marijuana in a chillum at the premises of Pashupatinath Temple, ahead of the Shivaratri festival in Kathmandu, Nepal February 15, 2017. (Photo by Navesh Chitrakar/Reuters)

A woman covers her face as men throw colored powder at her during “Lathmar Holi” at the village of Barsana in the northern Indian state of Uttar Pradesh March 9, 2014. (Photo by Anindito Mukherjee/Reuters)

Coloured X-ray of a barn owl. A physicist has used X-ray to create an extraordinary collection of artwork. Arie van't Riets pictures reveal birds, fish, monkeys and flowers in an incredible new light. The 66-year-old, from Bathmen in the Netherlands, began X-raying flowers as a means to teach radiographers and physicians how the machine worked. But after adding a bit of colour to the pictures, the retired medical physicist realised the potential for an exciting new collection of art. (Photo by Arie van't Riet/Barcroft Media)

Revelers celebrate the Indian festival of Holi on the deck of the ship Peking at South Street Seaport in Manhattan March 19, 2011 in New York City. The Hindu festival of Holi , also known as the Festival of Colors, marks the arrival of spring where participants throw colored powder and water on one another. Many of the New York participants are Indian-American.

Revelers take a selfie during a Holi Festival in Madrid, Spain, Sunday, April 26, 2015. The festival is based on the Hindu spring festival Holi, also known as the festival of colours where participants colour each other with dry powder and coloured water. (Photo by Andres Kudacki/AP Photo)

A devotee participates in Holi celebrations at the Nandagram temple, on March 22, 2013. (Photo by Manish Swarup/Associated Press)

Members of an Orthodox community take part in an Easter service at a church in the village of Poteryaevka, some 200 km (124 miles) southwest of the city of Barnaul in Russia's Altai region, on April 24, 2011. (Reuters/Andrei Kasprishin)

A man daubed in colours looks on as he takes part in “Lathmar Holi” celebrations inside a temple in the town of Barsana, in Uttar Pradesh, India, March 15, 2019. (Photo by Altaf Hussain/Reuters)