Fireworks explode over Elizabeth Tower housing the Big Ben clock in London. (Photo by Kirsty Wigglesworth/Associated Press)

The lightest material ever made has been produced by a team of scientists in China, a Chinese university announced.

A picture released by the North Korean Central News Agency (KCNA) shows Kim Jong-un convening an urgent operation meeting at 0:30 am on March 29, 2013 at an undisclosed location, in which he ordered strategic rocket forces to be on standby to strike US and South Korean targets at any time. (Photo by KCNA via EPA)

Crowds Gather For New Year's Ball Drop In Times Square on December 31, 2011 in New York City. (Photo by Michael Loccisano/Getty Images)

A performer dances in the Chinese New Year parade in Sydney on February 17, 2013. The parade featured more than 3,500 performers from Australia and China, including 120 performers from Shenzhen, Sydney's offical partner city for this year's festival. (Photo by William West/AFP Photo)

DJI Phantom 3 Severe Crash - Train Bridge

Historical reenactor Troy Kotz poses with a mug of wassail in the parlor of the Guyon-Lake-Tysen House during the annual Candlelight Tour of Historic Richmond Town, Saturday, December 13, 2014, in the Staten Island borough of New York. The annual event lets visitors experience an authentic Victorian Christmas. This image was made using the TinType by Hipstamatic iPhone app. (Photo by Chad Rachman/New York Post)

Swimmers in fancy dress splash as they participate in the New Year's Day Loony Dook swim at South Queensferry, Scotland January 1, 2015. (Photo by Russell Cheyne/Reuters)