Protesters begin to gather ahead of the UK Student Climate Network's Global Climate Strike at Millbank in London, England on September 20, 2019. (Photo by Gareth Fuller/PA Images via Getty Images)

Eurocopter's X³ high-speed hybrid helicopter demonstrator performs, September 6, 2010. The Eurocopter X³ (X-Cubed) is an experimental high-speed compound helicopter developed by Eurocopter (now Airbus Helicopters). A technology demonstration platform for Eurocopter “high-speed, long-range hybrid helicopter” or H³ concept, the X³ achieved 255 knots in level flight on 7 June 2013, setting an unofficial speed record for a helicopter. (Photo by Reuters/HO/Eurocopter/Penna)

An injured NATO soldier lies on the ground following a suicide car bomb attack that targeted foreign military vehicles in the Afghan capital Kabul on June 30,2015. A powerful blast hit downtown Kabul on June 30 as a suicide car bomber targeted foreign military vehicles, officials said, with casualties feared. The blast came on the main road to the airport, around 500 meters (550 yards) from the US embassy and near a base for foreign troops.“It was a suicide car bomber targeting a convoy of foreign forces in Kabul”, interior ministry spokesman Sediq Sediq said. (Photo by Wakil Kohsar/AFP Photo)

Students, dressed in a whole array of fancy dress outfits, were pictured on a wild night out to kick off Freshers' Week in Leeds, England on September 21, 2019. Freshers' Week is a period before the start of an academic year at a university or tertiary institutions. During this period, students participate in a wide range of social activities. (Photo by N B (PRESS) LTD)

Students from John Moores' University celebrate and pose for family photographs as they take part in their degree congregations at Liverpool's Anglican Cathedral on July 13, 2011 in Liverpool, England. Thousands of students are taking part in graduations across Britain and will begin looking for employment. According to recent surveys there are currently 83 graduates chasing every job vacancy. (Photo by Christopher Furlong/Getty Images)

(L-R) Diana, Renata, Marina, Sveta and Anastasia of the Showtime reality show “Russian Dolls” visit “The Chaunce Hayden Show” on GFQ Network at Sapphire New York on August 17, 2011 in New York City. (Photo by Theo Wargo/Getty Images)

Neil Tuckett and Jamie Davidson, begin their attempt to drive a 1911 Model T Ford to the top of Ben Nevis on May 16,2011 in Fort William, Scotland. The challenge has been organised in memory of a pioneering Edinburgh car dealer Henry Alexander, who drove to the top of Ben Nevis to prove the ruggedness of the Model T. The original accent took five days with the route leading over boulders and through snow drifts. (Photo by Jeff J Mitchell/Getty Images)