Researchers have created a new metallic material that they claim is the world's lightest solid material. With a density of just 0.9 mg/cm3 the material is around 100 times lighter than Styrofoam and lighter than the "multiwalled carbon nanotube (MCNT) aerogel" - also dubbed "frozen smoke" - with a density of 4 mg/cm3 that we looked at earlier this year. Despite being 99.99 percent open volume, the new material boasts impressive strength and energy absorption, making it potentially useful for a range of applications.

The 0.01 percent of the material that isn't air consists of a micro-lattice of interconnected hollow nickel-phosphorous tubes with a wall thickness of 100 nanometers - or 1,000 times thinner than a human hair. These tubes are angled to connect at nodes to form repeating, three-dimensional asterisk-like cells.

The new material draws parallels with large structures, such as the Eiffel Tower, which is incredibly light and weight-efficient thanks to its hierarchical lattice design. As an illustration of just how efficient such a design is, if the 7,300 tonnes of metal used in the Eiffel Tower were melted down it would fill just six centimeters (2.4 in) of the structure's 125 m2 (1,345 square ft) base.