An employee of the British Museum examines a silver coin dating from 900 AD which is part of the Silverdale Viking Hoard on December 14, 2011 in London, England. The hoard, which was discovered by local metal-detectorist Darren Webster in North Lancashire, comprises of 201 silver objects including arm-rings, coins, finger-rings, ingots, brooch fragments and fine wire braid. (Photo by Oli Scarff/Getty Images)

Pedestrians and traffic cross Tower Bridge as viewed through a glass viewing platform on the high-level Walkways during a preview to launch the new viewing experience at the Tower Bridge Exhibition centre in London on November 10, 2014. The new glass flooring at the Tower Bridge Exhibition 42 metres above the river Thames will allow visitors to gaze down on the bridge and river and allow them to experience the bridge opening from above. (Photo by Andrew Cowie/AFP Photo)

A view of the world's highest 280-meter bungee jumping platform opened at the Milad Tower, a landmark in the Iranian capital Tehran, on September 11, 2024. The world's highest bungee jumping platform attracts great interest among the younger generation in Iran, especially women. Those who jump from the platform experience an unforgettable adventure with the thrill of soaring down from a height of 280 meters while watching the view of Tehran from above. (Photo by Fatemeh Bahrami/Anadolu via Getty Images)

The Andromeda Galaxy, the nearest major galaxy to the Milky Way, can be seen shining above a remote village in Switzerland. The cinematic images convey the beauty of the galaxy gleaming above the picturesque Swiss mountains. Photographer Sandro Casutt took the amazing snaps in different seasons throughout the year, from his home valley of Vals, Switzerland. Here: A view of the sky from the Zervreila Mountain Lagoon in Switzerland. (Photo by Sandro Casutt/Caters News)

Tourists take a panoramic view of Kuala Lumpur from a skybox during a media preview at Kuala Lumpur Tower in Kuala Lumpur, Malaysia, 05 May 2016. Skybox, 421 metres above ground level will be the latest tourists attraction at Kuala Lumpur Tower, the 7th tallest freestanding tower in the world. (Photo by Ahmad Yusni/EPA)

Female panda Tian Tian makes her first appearance in front of the media since arriving from China on December 12, 2011 in Edinburgh, Scotland. (Photo by Jeff J. Mitchell/Getty Images)

Police dog handlers wait outside the Loftus Road stadium after FA Cup Fourth Round between Queens Park Rangers and Chelsea on January 28, 2012 in London, England. Security has been stepped up after QPR player Anton Ferdinand recieved a package containing a bullet. (Photo by Dan Kitwood/Getty Images)