When writers need to indicate that their super-advanced-spaceship crew are just as mystified by some alien artifact as you are, they often fall back on the tried and tested exclamation of “It’s made of some unknown element!” This always caused my eyes to roll—after all the last gap in the periodic table of the elements was filled in 1923 and while scientists do compete to add more artificially created elements to the bottom of the periodic table, these elements are incredibly unstable, with half-lives typically measured in fractions of a second. And even if one of these new elements were stable, they’d all be much heavier than lead, whereas, when handled by the spaceship crew, the alien artifact tends to behave more as if was made of materials with, perhaps, the density of plywood or plastic.

But now a group of Dutch researchers at the University of Delft have created substances that behave like totally a new type of element.  (more…)