罗塞塔探测器眼中的67P彗星

A year ago, the Rosetta Mission landed a probe on a comet - the first time this feat had been achieved. Rosetta has since revealed a whole load of fascinating facts about Comet 67P/Churyumov–Gerasimenko. Here are three things we’ve discovered about the comet so far, as well as three mysteries we have yet to solve…