A Thai Yoga enthusiast performs during a mass yoga exercise in Bangkok, Thailand, 16 June 2019. Hundreds of Thai and foreign Yoga enthusiasts took part in the mass Yoga exercise organized by the Indian embassy to mark the International Day of Yoga which annually celebrated on 21 June. (Photo by Rungroj Yongrit/EPA/EFE)

Michael Read, director of Flight Operations from New Zealand-based Martin Aircraft Company, flies a Martin Jetpack during a demonstration at a water park in Shenzhen, China December 6, 2015. KuangChi Science Ltd, a Hong Kong-listed Chinese company and investor of Martin Aircraft, will sell the flying machine in mainland China for 1.6 million yuan ($249,902), according to the company. (Photo by Bobby Yip/Reuters)

A Panasonic Toughpad is displayed during a press event at The Venetian for the 2012 International Consumer Electronics Show (CES) January 9, 2012 in Las Vegas, Nevada. CES, the world's largest annual consumer technology trade show, runs from January 10-13 and is expected to feature 2,700 exhibitors showing off their latest products and services to about 140,000 attendees. (Photo by Ethan Miller/Getty Images)

“A small British company with a dream of building a re-usable space plane has won an important endorsement from the European Space Agency (ESA) after completing key tests on its novel engine technology. Reaction Engines Ltd believes its Sabre engine, which would operate like a jet engine in the atmosphere and a rocket in space, could displace rockets for space access and transform air travel by bringing any destination on Earth to no more than four hours away”. – Chris Wickham via Reuters. Photo: Artist's impression of Skylon. (Photo by Reaction Engines Ltd)

In modern Russia there are no free elections, therefore the political elite is almost constant.

Photo: Valentina Matvienko, Mayor of St. Petersburg, attends the St. Petersburg International Economic Forum (SPIEF) on June 17, 2011 in St. Petersburg, Russia. Global business leaders have gathered in Russia for the three-day conference. (Photo by Alexander Aleshkin/Epsilon/Getty Images)

Chinelos (traditional costumed dancers) perform in front of San Andres Ocotlan church as part of continuing festivities to welcome the new year in Calimaya, Mexico on January 4, 2016. (Photo by Arturo Hernandez/Demotix/Corbis)

Public Space series, 2015. This series by Morteza Niknahad and Behnam Zakeri tends toward cinema, taking an almost cartoonish view of modern life in Iran. This work was inspired by the social life of dolphins. (Photo by Morteza Niknahad and Behnam Zakeri/The Guardian)

Marco Fiera from NoFit State Circus tries out the SkyWire, the new zip wire attraction which opens to the public this week at The Eden Project on July 17, 2012 in St Austell, England. The new 740m zip wire, currently the longest in England, allows the public a bird's eye view of the iconic Rainforest and Mediterranean Biome structures as well as the Cornish attractions outdoor gardens. The Eden Project – which opened in 2001 and has attracted over one million visitors – showcases 100,000 plants from around the world in two giant transparent domes, one of which is the world's largest greenhouse, each recreating different climate conditions. (Photo by Matt Cardy)