A boy rides on a snow wagon towed by a robot dressed as a Teddy bear, which only moves forward by moving its legs, during the Ice and snow carnival at Taoranting park in Beijing February 9, 2015. (Photo by Kim Kyung-Hoon/Reuters)

A colorful sky at sunset over the snowy mountains in Immenstadt, Bavaria, Germany, 20 November 2014. Cloudy weather is forecast in the region on 21 November. (Photo by Karl-Josef Hildenbrand/EPA)

An athlete pulls a 15-tonne truck during a Truck-Pull event marking the upcoming Independence Day in the Belarus capital Minsk, on July 3, 2014. The former Soviet nation celebrates its Independence Day on July 3 in memory of the end of Belarus occupation by Nazi Germany troops during the Red Army main summer offensive in 1944. (Photo by Sergei Gapon/AFP Photo)

In this September 19, 2014 photo, explosives are detonate by Peruvian counternarcotics forces on a part of a clandestine grassy airstrip in the Apurimac, Ene and Mantaro River Valleys, or VRAEM, the world's No. 1 coca-growing region, in Ayacucho, Peru. The dynamiting of craters by Peruvian security forces into clandestine airstrips cuts into profits but hardly discourages cocaine traffickers who net tens of thousands of dollars with each flight flown from these airstrips. (Photo by Rodrigo Abd/AP Photo)

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

An ice swimming enthusiast dressed as Neptune takes to the frigid waters of Orankesee lake during the 27th annual "Winter Swimming in Berlin" on January 8, 2011 in Berlin, Germany. A local swimmers' group called the “Berlin Seals” invite ice swimmers from across Germany and abroad to the annual event. Members claim ice swimming is good for the body's blood circulation. (Photo by Sean Gallup)

“The nuclear football (also known as the atomic football, the president's emergency satchel, the button, the black box, or just the football) is a briefcase, the contents of which are to be used by the President of the United States of America to authorize a nuclear attack while away from fixed command centers, such as the White House Situation Room. It functions as a mobile hub in the strategic defense system of the United States. It is a metallic Zero Halliburton briefcase carried in a black leather “jacket”. The package weighs around 45 pounds (20 kilograms). A small antenna protrudes from the bag near the handle”. – Wikipedia

Photo: A U.S. Military officer carries the “football”, which carries nuclear launch codes, on South Lawn after returning with U.S. President George W. Bush to the White House January 7, 2002 in Washington, DC. (Photo by Mark Wilson/Getty Images)