The volcano – among the most familiar and perhaps the most terrifying of all geological phenomena. However, Earth isn't the only planet to harbour volcanoes. In fact, the Solar System, and probably the entire Universe, is littered with them. Our own Moon, which is now a dormant piece of rock, had lava flowing across its surface billions of years ago, while Mars can be credited with the largest volcano in the Solar System, Olympus Mons, which stands 25km high. While Mars's volcanoes are long dead, volcanic activity continues in almost every other corner of the Solar System, in the most unexpected of locations.