Swiss pilot Bertrand Piccard prepares for a test flight of the solar-powered Solar Impulse 2 experimental aircraft in Payerne November 13, 2014. The aircraft, weighing 2.4 tons with a wingspan of 72 meters, is fitted with more than 17,000 solar cells. An attempt to fly around the world in stages using only solar energy will be made in 2015. (Photo by Ruben Sprich/Reuters)

A bomb-laden Su-25 jet at the Hmeimim air base in December 2015. Russia's lease agreement obliged Assad’s military to safeguard the perimeter of the Hmeimim base, while giving Moscow legal jurisdiction over the facilities inside. Negotiating perimeter protection from Syria’s new rulers will be vital for the Russian bases in an era of wire-controlled drones immune to jamming. (Photo by AP Photo)

Most Russians intending to vote for Vladimir Putin in Sunday's election say stability is at the root of their faith in their candidate – though many young voters believe it's time for a change of leader. Putin, 65, is expected to win a fourth term in office with 69 percent of the vote, according to the latest survey by a state-run pollster. Reuters correspondents and photographers who travelled around the country talking to voters ahead of the March 18 election found nothing to contradict expectation of an emphatic Putin victory. (Photo by Anton Vaganov/Reuters)

Police officers detain a Navalny supporter during a protest in St. Petersburg, Russia, Tuesday, February 2, 2021. A Moscow court has ordered Russian opposition leader Alexei Navalny to prison for more than 2 1/2 years on charges that he violated the terms of his probation while he was recuperating in Germany from nerve-agent poisoning. Navalny, who is the most prominent critic of President Vladimir Putin, had earlier denounced the proceedings as a vain attempt by the Kremlin to scare millions of Russians into submission. (Photo by Dmitri Lovetsky/AP Photo)

Boards stand lined up at the Rocinha Surf Association, ASR, headquarters at Rocinha slum in Rio de Janeiro, Brazil, Thursday, July 2, 2015. ASR has given free lessons to over 2,000 children from Rio's shantytowns in the hopes of keeping the boys, who are mostly in their early teens and a few girls occupied by the sport and off the streets. (Photo by Felipe Dana/AP Photo)

Li Guoqiang talks on his phone outside his house at Guangfuli neighbourhood, in Shanghai, China, April 1, 2016. Li, 38, is a deliveryman who rents a place at Guangfuli. In a corner of Shanghai, surrounded by a cement wall, lies one of the world's most valuable fields of debris and garbage. On paper, the Guangfuli neighbourhood is a real estate investor's dream: a plot in the middle of one of the world's most expensive and fast-rising property markets. But the reality is more like a developer's nightmare, thanks to hundreds of people living there who have refused to budge from their ramshackle homes for nearly 16 years as the local authority sought to clear the land for new construction. (Photo by Aly Song/Reuters)

Tourists visit the Corral Canyon Cave in Malibu, Calif., Friday, May, 6, 2016. The cave, better known by the misleading moniker “Jim Morrison Cave” is now closed to the public until further notice. Large crowds have shown up on a daily basis to see the often vandalized cave and in some cases add to the vandalism with graffiti of their own. (Photo by Damian Dovarganes/AP Photo)

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)