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)

A woman views the painting “Alegory of Love” by Marc Dennis at the “Hello! Exploring the Supercute World of Hello Kitty” museum exhibit in honor of Hello Kitty's 40th anniversary, at the Japanese American National Museum in Los Angeles, California October 10, 2014. (Photo by Lucy Nicholson/Reuters)

The hard-worked hands of Jacaba Coaquira, 80, holding the green beans she grew on her land. This year the production of her land was affected by lack of rain and early cold weather that froze the crops before they finished growing. Santiago de Okola, Bolivia. (Photo by Renée C. Byer/Living on a Dollar a Day)

A youth dives into a crater filled with water in Aleppo's al-Shaar district, in this July 10, 2014 file photo. (Photo by Hosam Katan/Reuters)

Family members mourn the passing of Manuela Chavez, who died from symptoms related to the new coronavirus at the age of 88, as a government team prepares to remove her body from inside her home, in the Shipibo Indigenous community of Pucallpa, in Peru's Ucayali region, Monday, August 31, 2020. While the lucky are cured with ancestral ailments, the less fortunate often die at home. A government team travels from one spartan, thatch-roofed home to the next, removing the dead from their homes where they took their last breaths. (Photo by Rodrigo Abd/AP Photo)

A taxi driver seen sleeping on his taxi in the middle of a decorated street during the Durga Puja Festival in Kolkata, India on October 22, 2020. (Photo by Avishek Das/SOPA Images/Rex Features/Shutterstock)

Passengers wears a face mask while riding on a bus after new cases of COVID-19 were reported in Peshawar, Pakistan, 18 November 2020. Countries around the world are taking increased measures to stem the widespread of the Covid-19 disease. (Photo by Arshad Arbab/EPA/EFE/Rex Features/Shutterstock)

Young women pose for photos in a Christmas-themed tunnel lit-up with decorations outside a shopping mall in Bangkok on December 4, 2020. (Photo by Mladen Antonov/AFP Photo)