An Afghan girl carries water on her back as she climbs a hill in Kabul, Afghanistan February 20, 2017. A growing population is straining water supplies in Afghanistan's capital, forcing those who can afford it to dig unregulated wells ever deeper to tap a falling water table. Finding water in arid Afghanistan is virtually always a challenge, but a drop in the groundwater level in Kabul caused by overuse and drought is making it even more difficult for residents, especially the poor. (Photo by Omar Sobhani/Reuters)

The National September 11 Memorial & Museum (branded as 9/11 Memorial and 9/11 Memorial Museum) is the principal memorial and museum commemorating the September 11 attacks of 2001, which killed nearly 3,000 people, and the World Trade Center bombing of 1993, which killed six. The memorial is located at the World Trade Center site, on the former location of the Twin Towers, which were destroyed during the attacks. The World Trade Center Memorial Foundation was renamed the National September 11 Memorial & Museum at the World Trade Center in 2007.

The giant inflatable Rubber Duck installation by Dutch artist Florentijn Hofman floats on the Parramatta River, as part of the 2014 Sydney Festival, in Western Sydney, January 10, 2014. The creation is five stories tall and five stories wide and has been seen floating in various cities around the world since 2007. (Photo by Jason Reed/Reuters)

A pro-independence protester sits in front of Catalonia's regional parliament as lawmakers vote inside, in Barcelona, January 16, 2014. (Photo by Albert Gea/Reuters)

A refugee sits in front of a Greek riot police cordon during a protest at the Greek-Macedonian border, near the Greek village of Idomeni, March 1, 2016. (Photo by Alexandros Avramidis/Reuters)

“In 1967, Zhang Yaxin was 34 and working as a photojournalist at China’s state-controlled Xinhua News Agency when he was assigned to a top-secret government project. He was to be the official photographer of a new arts program led by Chairman Mao and his wife – the Model Operas. Though he was not to know it then, Zhang would spend the next seven years documenting the evolution of one of the most dramatic and elaborate attempts to redefine artistic sensibilities in modern art history”. – Chengcheng Jiang via TIME. Photo: Raid on the White Tiger Regiment, 1971. (Photo by Zhang Yaxin/Courtesy See+ Gallery, Beijing)

“Burning Man is a week-long annual event held in the Black Rock Desert in northern Nevada, in the United States. The event starts on the Monday before the American Labor Day holiday, and ends on the holiday itself. It takes its name from the ritual burning of a large wooden effigy on Saturday evening. The event is described by many participants as an experiment in community, radical self-expression, and radical self-reliance”. – Wikipedia

Photo: A fireball billows up from a 52-foot tall wooden man as it goes up in flames September 2, 2000 during the15th annual Burning Man festival in the Black Rock Desert near Gerlach, Nevada. Despite high winds, dust storms, and a bit of rain, some 27,000 people camped out on a remote desert playa, or dry lake, for the week-long counter-cultural celebration of art and “radical self-expression”. (Photo by David McNew/Newsmakers)

The lightest material ever made has been produced by a team of scientists in China, a Chinese university announced.