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)

Revellers continue to party and dance through the night and day during the second day of the San Fermin Running Of The Bulls festival, on July 7, 2014 in Pamplona, Spain. The annual Fiesta de San Fermin, made famous by the 1926 novel of US writer Ernest Hemmingway “The Sun Also Rises”, involves the running of the bulls through the historic heart of Pamplona. (Photo by Christopher Furlong/Getty Images)

An employee of Paris city Hall removes padlocks clipped by lovers on the fence of the Pont des Arts over the River Seine in Paris, December 9, 2014. For years, visiting couples have hung brass padlocks on the iron grills lining the city's bridges to symbolise their undying love – they write their names on the locks, then toss the key into the Seine below. About 700,000 love locks are added every few months and Paris officials say they are damaging the bridges and threatening safety because of the added weight. (Photo by Philippe Wojazer/Reuters)

Mariam Ashraf, a teacher and “natural hair influencer”, speaks before a phone on a tripod and lights during a live-stream at her home in Egypt's capital Cairo on March 22, 2022. “Shaggy”, “messy”, “unprofessional”. Natural curls were once looked down upon in Egypt, where Western beauty standards favoured sleek, straight locks. Now, things are changing. (Photo by Khaled Desouki/AFP Photo)

An injured protestor grieves in pain as police fire tear gas to disperse protesting members of the Inter University Students Federation during an anti government protest in Colombo, Sri Lanka, Thursday, May 19, 2022. Sri Lankans have been protesting for more than a month demanding the resignation of President Gotabaya Rajapaksa, holding him responsible for the country's worst economic crisis in recent memory. (Photo by Eranga Jayawardena/AP Photo)

Pilot Commissioner Ozge Karabulut prepares to take off during World Pilots Day in Ankara, Turkiye on April 25, 2022. Pilot Commissioner Ebru Melek (not seen) who has been involved in the fight against criminals, especially terrorism, within the body of the Aviation Department of the General Directorate of Security, which has ensured peace and security in the skies of the homeland for 41 years with aircraft, of Turkish Police Service and Turkiye's the first female attack helicopter Pilot Commissioner Ozge Karabulut celebrate her colleagues World Pilots' Day on April 26th. (Photo by Aytac Unal/Anadolu Agency via Getty Images)

The Wadi al-Salam cemetery, Arabic for “Peace Valley”, is seen in Najaf, south of Baghdad, Iraq August 3, 2016. The world's largest cemetery, in Iraq's Shi'ite holy city of Najaf, is expanding at double its usual rate as Shi'ite militias bury their dead from the war against Islamic State. The Wadi al-Salam cemetery, Arabic for “Peace Valley” has a special place in the hearts of Shi'ite Muslims as it surrounds the Mausoleum of their first imam, Ali Bin Abi Talib, a cousin and son-in-law of Prophet Mohammad. (Photo by Alaa Al-Marjani/Reuters)

Ukrainians jump over a fire in Kiev, Ukraine, 06 July 2017, as they celebrate the traditional pagan holiday of Ivana Kupala. Ivana Kupala is celebrated, during the summer solstice, on the shortest night of the year, marking the beginning of summer and is celebrated in Ukraine, Belarus, Poland and Russia on the night of 06 July. People sing and dance around bonfires, play games and perform traditional rituals. Young people jump over bonfires in order to test their bravery. Couples holding hands jump over the flames to test their love. If the couple does not succeed it is predicted to split up. Traditionally, children and young unmarried women wear wreaths of wild flowers on their heads to symbolize purity. (Photo by Sergey Dolzhenko/EPA)