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)

Green building also known as green construction or sustainable building is the practice of creating structures and using processes that are environmentally responsible and resource-efficient.

Competitors warm up backstage during the Arnold Classic Europe bodybuilding event in Madrid, Spain, September 25, 2015. (Photo by Susana Vera/Reuters)

The X-47B prototype on Tuesday flew off an aircraft carrier and into the history books. Today's achievement, the first-ever catapult launch of an unmanned aircraft from the flight deck of a carrier, promises to open up a new chapter in the annals of naval aviation. Photo: An X-47B pilot-less drone combat aircraft is launched for the first time off an aircraft carrier, the USS George H. W. Bush, in the Atlantic Ocean off the coast of Virginia, May 14, 2013. The U.S. Navy made aviation history on Tuesday by catapulting an unmanned jet off an aircraft carrier for the first time, testing a long-range, stealthy, bat-winged plane that represents a jump forward in drone technology. (Photo by Jason Reed/Reuters)

Flames rage through a pile of tires at the tire dump of Sesena in Toledo, Spain, 13 May 2016. The tire dump reportedly contains over 100,000 tons of tires and reaches to the neighbouring town of Valdemoro in Madrid. According to local authorities, the fire was apparently deliberately started as it had been raining till midnight and the fire started early 13 May 2016 at a small spot in Valdemoro. (Photo by Ismael Herrero/EPA)

A girl holds up a photo of Pope Benedict XVI which reads “tear his face” during a protest against the World Youth Day 2011 celebrations taking place on August 17, 2011 in Madrid, Spain. Initiated by Pope John Paul II in 1985, World Youth Day youth-oriented events for the celebration of the Catholic faith are held every three years in a different country; this time in Madrid from August 16 – 21, with Pope Benedict XVI in attendance. (Photo by Denis Doyle/Getty Images)

A model walks the runway in the Maria Escote fashion show during the Mercedes-Benz Fashion Week Madrid Autumn/Winter 2012 at Ifema on February 4, 2012 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

Sofi Tukker x Amadou & Mariam – Mon Cheri (Official Music Video). “Mon Cheri” continues Red Hot's 30-year mission of fighting HIV/AIDS and supporting humanitarian charities through music, pop culture and global anthems.