On the 25th of May 1997 a dramatic collision tore a hole into the space station Mir and sent it hurtling through space. As NASA astronaut Michael Foale tells Plus, the fate of Mir and its crew hinged on a classical set of equations.
In last issue's Graphical methods I Phil Wilson used maths to predict the outcome of a cold war in slug world. In this self-contained article he looks at slug world after the disaster: with only a few survivors and all infra-structure destroyed, which species will take root and how will they develop? Graphs can tell it all.
Everyone knows what symmetry is, and the ability to spot it seems to be hard-wired into our brains. Mario Livio explains how not only shapes, but also laws of nature can be symmetrical, and how this aids our understanding of the universe.