This is a new material, “aerographite,” synthesized by scientists from Kiel University and Hamburg University of Technology. They have a press release:
A network of porous carbon tubes that is three-dimensionally interwoven at nano and micro level – this is the lightest material in the world. It weights only 0.2 milligrams per cubic centimetre, and is therefore 75 times lighter than Styrofoam …
Despite of its low weight Aerographite is highly resilient. While lightweight materials normally withstand compression but not tension, Aerographite features both: an excellent compression and tension load. It is able to be compressed up to 95 percent and be pulled back to its original form without any damage, says professor Rainer Adelung of Kiel University.