A new LED light fixture is secured to the side of a lift as crews replace existing street lights August 1, 2011 in Las Vegas, Nevada. The new energy-efficient fixtures are expected to reduce the city's annual electricity use by eight million kilowatt hours, saving about USD 400,000. The city estimates the LEDs will last about 15 years, nine years longer than the current lights. Funding for the project comes from federal energy conservation bonds and an American Recovery & Reinvestment Act grant. The city plans to replace all of its 50,000 streetlights after more funding is secured. (Photo by Ethan Miller/Getty Images)

“Thor Heyerdahl (October 6, 1914, Larvik, Norway – April 18, 2002, Colla Micheri, Italy) was a Norwegian ethnographer and adventurer with a background in zoology and geography. He became notable for his Kon-Tiki expedition, in which he sailed 8,000 km (4,300 miles) by raft from South America to the Tuamotu Islands. All his expeditions are shown in the Kon-Tiki Museum, Oslo”. – Wikipedia

Photo: Norwegian anthropologist Thor Heyerdahl with a model of the balsa raft “Kon-Tiki” on which he drifted 4,300 miles from Peru to the Tuamotu Islands, proving his theory that Polynesia could originally have been populated by South Americans. (Photo by Express/Express/Getty Images). 1950

These stunning images look to highlight the amazing natural beauty that can be found across the United States. The U.S. Department of the Interior (DOI) recently released their Best of 2015 list, featuring a variety of animals, weather conditions and landmarks. Included in the list are gleaming auroras, adorable groups of otters and owls, and breath-taking shots across the likes of the Grand Canyon and national parks. Each of the spectacular shots, all of which were taken during 2015, featured on the Department of the Interiors Instagram account throughout the year, taken by both members of staff and members of the public. Here: Arches, National Park. (Photo by Caters News)

This year's Republican National Convention and Democratic National Convention both saw passionate delegates in outrageous costumes – but that's where the similarities mostly end. Reuters photographer Jim Young gives a look at what it's like to be on the convention floor and talks to the delegates who make the conventions memorable. (Photo by Jim Young/Reuters)

This picture taken on March 16, 2017 shows a crew member introducing the dining car of the Train Suite Shiki- Shima, operated by East Japan Railway, in Tokyo during a press preview. The luxury sleeper Shiki- Shima, which can accommodate up to 34 passengers, has 10 cars, including a lounge car, a dining car and two observatory cars. The train has only 17 cabins, all suites, and the most expensive room, known as Shiki- Shima Suite, is priced at 950,000 yen (8480 USD) per person when shared by two people. (Photo by AFP Photo/JIJI Press)

Associated Press photographer Wong Maye-E tries to get her North Korean subjects to open up as much as is possible in an authoritarian country with no tolerance for dissent and great distrust of foreigners. She has taken dozens of portraits of North Koreans over the past three years, often after breaking the ice by taking photos with an instant camera and sharing them. Her question for everyone she photographs: What is your motto? Their answers reflect both their varied lives and the government that looms incessantly over all of them. (Photo by Wong Maye-E/AP Photo)

These stunning images reveal the remains of a more than century-old sunken ship that has been preserved beneath freezing Lake Superior. The ship looks almost exactly the same as it did the day it sunk beneath waves all those years ago. At 60 meters long (approximately 198 feet), the «Gunilda» sunk after it struck some rocks and was not saved. Now, these stunning images have been captured 107 years after the sinking when a small group of divers revisited the vessel. (Photo by Becky Kagan Schott/Caters News Agency)

“The Daleks are a fictional extraterrestrial race of genetically manipulated mutants from the British science fiction television series Doctor Who. Various storylines portray them as having had every emotion removed except hate, leaving them with a desire to purge the Universe of all non-Dalek life. Collectively they are the greatest enemies of the series' protagonist, the Time Lord known as the Doctor. Their famous catchphrase is “Exterminate!”, with each syllable individually synthesised in a frantic electronic voice” – Wikipedia

Photo: Max Hardy, aged 6, stands by a street sign from the Doctor Who Experience as Dalek, from the cult television show Doctor Who watches him on April 16, 2011 in London, England. The Doctor Who Experience Exhibition is currently running at Kensington Olympia Two, celebrating the science fiction programme that was originally screened in 1963. (Photo by Matthew Lloyd/Getty Images for BBC Worldwide)