People visit the art installation “Machine Memories: Space” by Turkish artist Refik Anadol in the exhibition at Pilevneli Art Gallery in I​stanbul, Turkey, 22 March 2021. The exhibition runs until 25 April. (Photo by Sedat Suna/EPA/EFE)

Indian holy men, or Naga Sadhu, ride a motorbike on their way to take a holy dip in the Ganges River during the Kumbh Mela at Haridwar, Uttarakhand, India, 14 April 2021. Thousands of pilgrims gather for the mass Hindu pilgrimage which occurs every twelve years and rotates among four locations. (Photo by Idrees Mohammed/EPA/EFE)

Santa Claus reacts as (L) Tami McEleney and (R) Patrice Conner whisper in his ear at the King of Prussia Mall, United States' largest retail shopping space, in King of Prussia, Pennsylvania, U.S., December 8, 2018. (Photo by Mark Makela/Reuters)

Los Angeles Rams cheerleaders including the first two male cheerleaders in Super Bowl history (C) perform in the third quarter of Super Bowl LIII between the New England Patriots and the Los Angeles Rams at Mercedes-Benz Stadium in Atlanta, Georgia, USA, 03 February 2019. (Photo by Mike Zarrilli/EPA/EFE)

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)

An India Christian devotee reenacts the sufferings of Jesus Christ on the occasion of Good Friday in Mumbai, India, Friday, March 29, 2013. Christians all over the world are marking Good Friday, the day when Christ was crucified. (Photo by Rajanish Kakade/AP Photo)

A fox runs out onto the pitch before the start of the second half. Celtic League 2012/13, Round 19, Leinster v Ulster, RDS, Ballsbridge, Dublin, March 30, 2013. (Photo by Paul Mohan)

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)