If visitors came here from outer space, they could very well find themselves receiving a most savage welcome - with rivers of fire and all manner of noxious gases exuding into the atmosphere - to say nothing of hunks of red-hot rock flying in all directions. One can imagine them saying to each other: 'If this is planet Earth, then let's forget it.'
Anthony Smith takes a look at some of the awesome, yet spectacular, volcanic eruptions around the world. Photographed by MAURICE AND KATIA KRAFFT
BBCtv presentation GEORGE INGER