Sarah Bui poses for photographer, Brian Le around blossoming cherry trees, near the Tidal Basin on Thursday March 23, 2017 in Washington, DC. (Photo by Matt McClain/The Washington Post)

Rooftops of solar powered houses are pictured in Ota, 80 km northwest of Tokyo in this October 28, 2008 file photo. One by one, Japan is turning off the lights at the giant oil-fired power plants that propelled it to the ranks of the world's top industrialised nations. With nuclear power in the doldrums after the Fukushima disaster, it's solar energy that is becoming the alternative. Solar power is set to become profitable in Japan as early as this quarter, according to the Japan Renewable Energy Foundation (JREF), freeing it from the need for government subsidies and making it the last of the G7 economies where the technology has become economically viable. (Photo by Yuriko Nakao/Reuters)

In this photograph taken on April 16, 2014, a veterinary staff member of the Sumatran Orangutan Conservation Programme center conducts medical examinations on a 14-year-old male orangutan found with air gun metal pellets embedded in his body in Sibolangit district in northern Sumatra island. (Photo by Sutanta Aditya/AFP Photo)

“NASA's Pathfinder, Pathfinder Plus, Centurion and Helios Prototype were an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) program. They were built to develop the technologies that would allow long-term, high-altitude aircraft to serve as “atmospheric satellites”, to perform atmospheric research tasks as well as serve as communications platforms”. – Wikipedia

Photo: The solar-electric Helios Prototype flying wing is flies over the Hawaiian islands of Niihau and Lehua during the first solar-powered test flight July 14, 2001 from the U.S. Navy's Pacific Missile Range Facility on Kauai, HI. The 18-hour flight was a functional checkout of the aircraft's systems and performance in preparation for an attempt to reach sustained flight at 100,000 feet altitude later in the summer. (Photo Courtesy of NASA/Getty Images)

People visit an art installation “Alley of Flying Umbrellas” in central St. Petersburg, Russia, May 15, 2015. Art installation inspired by “Umbrella Sky Project” of Portuguese town of Agueda and was made of 500 colored umbrellas. (Photo by Anatoly Maltsev/EPA)

The winners of The London’s Natural History Museum's prestigious Wildlife Photographer of the Year for 2013 have finally been unveiled. Selected from almost 43,000 entries from 96 countries, the winners offer a glimpse of the stunning array of natural beauty on our planet. Photo: Canada: “Lucky pounce”. “Anticipating the pounce – that was the hardest part”, says Connor, who had come to Yellowstone National Park, Wyoming, USA, in search of wildlife as much as the spectacular landscape. He had found this fox, his first ever, on his last day in the park. It was so absorbed in hunting that Connor had plenty of time to get out of the car and settle behind a rock. It quartered the grassland, back and forth, and then started staring intently at a patch of ground, giving Connor just enough warning of the action to come. When it sprung up, Connor got his shot. And when it landed, the fox got his mouse. (Photo by Connor Stefanison/Wildlife Photographer of the Year 2013)

An ancient oak tree sits in a Shropshire field as the first signs of Spring begin to show across the United Kingdom on February 19, 2014 in Bridgnorth, England. (Photo by Christopher Furlong/Getty Images)

A tourist clad in Japanese kimono takes a picture in front of s portrait shop in Tokyo's Asakusa district, Thursday, February 15, 2018. Asakusa is a popular district four tourists in the capital. (Photo by Shizuo Kambayashi/AP Photo)