* Astronomy

Ethereal aerographite is lightest stuff ever made

With a density of less than 0.2 mg/cm³, it is barely there at all. Researchers at the Hamburg University of Technology and the University of Kiel, both in Germany, made it from a network of hollow carbon tubes grown at nano and micro scales. As the electron microscope picture above shows, it is mostly empty space, though if you held a clump in your hand, it would look like a black sponge.
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