Boys dressed in historical uniforms stand before a military parade in Red Square in Moscow November 7, 2014. The parade marked the anniversary of the 1941 parade when Soviet soldiers marched through the Red Square towards the front lines of World War Two. (Photo by Maxim Shemetov/Reuters)

Spectators in Moscow were treated to the site of humorously designed makeshift aircraft plunging into the Muskova River during the Red Bull Flugtag Moscow 2011 competition. 38 teams took part at the Flugtag – which means “flying day” – a competition in which teams in fancy dress attempt to pilot human-powered, home-made flying machines off a six-meter-high platform into water.

Photo: A makeshift aircraft plummets into the Moskva River during the Red Bull Flugtag Moscow 2011 competition. (Photo by Sergei Karpukhin/Reuters)

People watch a competitor riding a homemade vehicle without an engine on a 300-metre-track during the Red Bull Soapbox Race in Amman, Jordan September 4, 2015. (Photo by Muhammad Hamed/Reuters)

Head of European Prints, Severine Nackers holds a celestial Map of the Southern Sky by Albrecht Durer, at Sotheby's Auction House on March 25, 2011 in London, England. The two woodcut maps depicting the Northern and Southern skies circa 1515, are the earliest printed star charts of their kind ever published in Europe, and are expected to fetch between Ј120,000-180,000 GBP when they go on sale at the “London sale of Old Master, Modern and Contemporary prints” at Sotheby's Auction house on March 30, 2011. (Photo by Dan Kitwood/Getty Images)

French artist Thomas Lamadieu, also know as Roots Art, must really love looking at the sky. Every time he looks up, Thomas sees a potential canvas where the building rooftops frame the sky. He photographs it and uses the odd sky shapes to create whimsical line drawings. “My artistic aim is to show a different perception of urban architecture and the everyday environment around us, what we can construct with a boundless imagination,” says Thomas. (Photo by Thomas Lamadieu)

Starting on Monday, August 12, Perseid meteors will streak across the summer sky for a couple of nights, offering casual stargazers and serious nighttime photographers a chance to capture a glimpse of the annual meteor shower. Photo: Photographer David Kingham created this composite image from 23 photos on August 12, 2012. (Photo by David Kingham)

Chinese artist Kong Ning walks in her costume made of hundreds of orange plastic blowing horns during her art performance raising awareness of the hazardous smog in front of the Drum tower in a historical part of Beijing on a very polluted day December 7, 2015. Kong, whose works include themes related to China's air pollution problem, named her new performance “The Orange Horns Bride Marries the Blue Sky” and presented it dressed in orange, the colour of the second highest pollution alert level issued again in Beijing as hazardous smog blankets the capital. (Photo by Damir Sagolj/Reuters)

A man participates in the Red Bull Jump & Freeze Lebanon at Mzaar Kfardebian Ski Resort in mount Lebanon February 28, 2016. (Photo by Jamal Saidi/Reuters)