Passengers pose for a selfie as they wait for the Night Tube train service at Oxford Circus on the London underground system in London, Britain August 20, 2016. The London Underground is starting its first-ever overnight service, a move city leaders hope will make the British capital a truly 24-hour city and bolster the local economy. (Photo by Paul Hackett/Reuters)

Members of the media film as a ranger performs a post mortem on the carcass of a rhino after it was killed for its horn by poachers at the Kruger national park in Mpumalanga province August 27, 2014. Rhino poachers in South Africa now risk giving themselves away when they shoot thanks to a high-tech, gunfire-detection system being piloted in the country's flagship Kruger National Park. The stakes are high, for rhinos are being slain in escalating numbers for their prized horns, alarming both conservationists and the government since wildlife in South Africa is an important tourist draw. (Photo by Siphiwe Sibeko/Reuters)

Four pillars of light from the 4 Laser Guide Star Facility on ESO's Very Large Telescope (VLT) are shown reaching into the Chilean night sky in this image from ESO Photo Ambassador Fred Kamphues, on September 2, 2016. The lasers are a key part of the adaptive optics system on the VLT. Adaptive optics allows astronomers to drastically reduce the atmospheric distortion present at even the best sites in the world for astronomy, including Paranal in Chile, the home of the VLT. (Photo by F. Kamphues/ESO)

Zhou Xiaoxuan, center, weeps as she speaks to her supporters upon arrival at a courthouse in Beijing, Wednesday, December 2, 2020. Zhou, a Chinese woman who filed a sexual harassment lawsuit against a TV host, told dozens of cheering supporters at a courthouse Wednesday she hopes her case will encourage other victims of gender violence in a system that gives them few options to pursue complaints. (Photo by Andy Wong/AP Photo)

Spot, a robot with dog-like movements, walks past a dog in Cathedral Square in Erfurt, Germany on April 20, 2021. Security service provider Ciborius, a provider of robotic security solutions with artificial intelligence, presented its artificial employee with high-resolution 360-degree all-round camera, ultra-bright LED light and a light detection system on Domplatz. (Photo by Michael Reichel/dpa)

Muqtada Haider turns the switches to transfer electricity to private homes in Baghdad, Iraq, Friday, September 10, 2021. In Iraq, electricity is a potent symbol of endemic corruption, rooted in the country’s sectarian power-sharing system. This contributes to chronic electrical outages of up to 14 hours a day in a major oil-producing nation with plentiful energy resources. (Photo by Hadi Mizban/AP Photo)

Girls practice sit-ups during gymnastics lessons at the Shanghai Yangpu Youth Amateur Athletic School in Shanghai, China, on May 4, 2016. China's sports system has been enormously successful since the country returned to the Olympic fold in 1980, culminating with the host nation topping the medals' table at the 2008 Beijing Olympics. And yet, with the Rio de Janeiro Games less than three months away, the system is beginning to break down due to the shifting demographics of a more prosperous nation. (Photo by Aly Song/Reuters)

Vets of Animals Asia Foundation's Vietnam Bear Rescue Center hold a paw of a sun bear as they check its health while it is rescued from a Vietnamese family in Nam Dinh province, south of Hanoi, Vietnam August 18, 2016. A man in northern Vietnam has voluntarily handed over a bear his family had caged for seven years to an animal rights organization, which will take it to a nearby sanctuary. (Photo by Reuters/Kham)