President Barack Obama watches as Joey Hudy (L), 14, from Phoenix, Arizona pumps the Extreme Marshmallow Cannon he invented, while touring student science fair projects on exhibit in the State Dining Room at the White House February 7, 2012 in Washington, DC. Obama hosted the second White House Science Fair celebrating the student winners of science, technology, engineering and math (STEM) competitions from across the country. (Photo by Molly Riley-Pool/Getty Images)

An Afghan policeman stands guard as smoke and flames rise from the site of a huge blast struck near the entrance of Kabul's international airport, in Kabul on August 10, 2015. A huge blast struck near the entrance of Kabul's international airport on August 10 during the peak lunchtime period, officials said, warning that heavy casualties were expected. “The explosion occurred at the first check point of Kabul airport”, said deputy Kabul police chief Sayed Gul Agha Rouhani. (Photo by Shah Marai/AFP Photo)

“A monowheel is a one-wheeled single-track vehicle similar to a unicycle. However, instead of sitting above the wheel, the rider sits either within it or next to it. The wheel is a ring, usually driven by smaller wheels pressing against its inner rim. Most are single-passenger vehicles, though multi-passenger models have been built.

Pedal-powered monowheels were built in the late 19th century; most built in the 20th century have been motorized. Some modern builders refer to these vehicles as monocycles, though that term is also sometimes used to describe motorized unicycles. Today, monowheels are generally built and used for fun and entertainment purposes, though from the 1860s through to the 1930s, they were proposed for use as serious transportation”. – Wikipedia

Photo: Cycle inventor Kerry McLean poses for the photographer 2000 in Walled Lake, Michigan. The “Monocycle” is equipped with a 40-horsepower engine, 4ft tire and is expected to reach speeds upwards of 100 mph. (Photo by Bill Pugliano/Liaison)

Wang Jiayun, born June 18 1993. Wang’s height is 164cm, her weight 42kg. Wang Jiayun says she was born in Kowloon of Hong Kong Special Administrative Region, and presently lives in Shenzhen City of Guangdong province in China. Identity: High school student. Wang's large eyes, pale face, perfectly structured nose and extremely slim figure resemble a brand of human-sized blow-up doll popular with Korean men. This cute and s*xy barbie doll look a like is hot property. She recently became the No.1 searched name in the country's top search engine, Naver.com. Photo: Wang Jia Yun (王嘉韻 or 왕지아인). (Photo by Wang Jia Yun)

A SpaceX Falcon Heavy rocket lifts off from historic launch pad 39-A at the Kennedy Space Center in Cape Canaveral, Florida, February 6, 2018. The world' s most powerful rocket, SpaceX' s Falcon Heavy, blasted off Tuesday on its highly anticipated maiden test flight, carrying CEO Elon Musk' s cherry red Tesla roadster to an orbit near Mars. Screams and cheers erupted at Cape Canaveral, Florida as the massive rocket fired its 27 engines and rumbled into the blue sky over the same NASA launchpad that served as a base for the US missions to Moon four decades ago. (Photo by Thom Baur/Reuters)

A Palestinian beekeeper uses smoke to calm bees in the process of collecting honey at a farm in Rafah, in the southern Gaza Strip April 11, 2016. Rateb Samour sees 250 patients a day, whose complaints range from hair loss to cerebral palsy and cancer. He is not a doctor and has never worked in a hospital. Samour inherited the skill of bee-sting therapy from his father. From 2003 the agricultural engineer dedicated all his time to study and develop the alternative-medicine treatment of apitherapy, which uses bee-related products from honey, propolis – or bee glue used to build hives – to venom. (Photo by Suhaib Salem/Reuters)

An internally displaced woman collects water from a pond to construct a mud-house at the Aboushok camp in El Fasher, North Darfur, Sudan, November 17, 2015. The conflict in Sudan's Darfur region that erupted 12 years ago shows no sign of ending. But it hasn't stopped displaced youngsters, some of whom have spent their entire lives in refugee camps, from dreaming big. Twelve children aged 12 explain their hopes and dreams for the future; ambitions include becoming a doctor, an engineer and a teacher. (Photo by Mohamed Nureldin Abdallah/Reuters)

“The V-30 Warhawk was designed by Blackshaw Avionics as a long-range fighter and was primarily used by the Arcadian Air Force for escort duties. The plane pictured is the “Spirit of Freedom” and was one of the four planes that escorted the Arcadian Royal Airship during and after the Great War. The three other fighters were the “Spirit of Hope”, the “Spirit of Justice” and the “Spirit of Destiny”. All pilots were hand-picked by the Head of Airborne Forces and included some of the very finest pilots in the Kingdom. The crew consisted of one pilot and one gunner although both cabins were fitted so that if either crew member was killed the other could take over their duties. Each Warhawk was fitted with four Haverlock “Banshee” engines and four 24mm machine guns”. (Photo and comment by Jon Hall)