Performers of circus company Circa perform during a photocall for the Edinburgh Festival Fringe on Calton Hill on August 1, 2017 in Edinburgh, United Kingdom. (Photo by Murdo MacLeod/The Guardian)

Pfc. Remy Bouchard swaps a cigarette for an egg with a French Orphan near La Haye Du Puits, France on July 18, 1944, which was captured by American forces. The boy is only twelve years old. (Photo by Hugh Broderick/AP Photo)

Amanda Ashe of Oakland, left, faces off with a police officer during the second night of demonstrations in Emeryville, California, following the grand jury decision in the shooting of Michael Brown in Ferguson, Missouri, November 25, 2014. (Photo by Elijah Nouvelage/Reuters)

Girls of University of Cincinnati Stage Grecian Games on April 29, 1921. Garbed in costumes of ancient Greece, fair students of the University of Cincinnati, Ohio arranged a set of Grecian Games for the benefit of the University athletic fund. All of the girl students of the University, who take a great interest in outdoor games and athletics, took part in the games. The fund was greatly increased through the staging of the unique attraction and the girls purpose to give a return engagement. The accompanying photographs show the girl contestants in their Grecian costumes. Photo shows the start of the 100 yard dash. (Photo by Bettmann Archive/Getty Images)

A general view of the Vintage and Rare Guitars shop on Denmark Street on April 20, 2011 in London, England. Denmark Street, in the Soho area of central London, traces its musical connections back to the 1890s and is famous for its connection to contemporary British music after recording studios started setting up there in the 1960s. Many world-renowned recording artists, including: Jimi Hendrix, The s*x Pistols and Elton John have played and recorded in the street. The Rolling Stones recorded their first album in 1964 at the street's Regent Sounds Studio's. Known as London's 'Tin Pan Alley' Denmark Street is regarded as one of, if not the, best music streets in Europe and contains numerous specialist music shops, with many boasting of a long and prestigious musical history.

“The frilled shark (Chlamydoselachus anguineus) is one of two extant species of shark in the family Chlamydoselachidae, with a wide but patchy distribution in the Atlantic and Pacific Oceans. This uncommon species is found over the outer continental shelf and upper continental slope, generally near the bottom though there is evidence of substantial upward movements. It has been caught as deep as 1,570 m (5,150 ft), whereas in Suruga Bay, Japan it is most common at depths of 50–200 m (160–660 ft). Exhibiting several “primitive” features, the frilled shark has often been termed a «living fossil»”. – Wikipedia

Photo: A 1.6 meter long Frill shark swims in a tank after being found by a fisherman at a bay in Numazu, on January 21, 2007 in Numazu, Japan. The frill shark, also known as a Frilled shark usually lives in waters of a depth of 600 meters and so it is very rare that this shark is found alive at sea-level. It's body shape and the number of gill are similar to fossils of sharks which lived 350,000,000 years ago. (Photo by Awashima Marine Park/Getty Images)

“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)