Isaac Asimov publishes Pebble in the Sky, his first science-fiction novel. And Earth enters a brand new epoch – according to some geologists. Now the idea of the Anthropocene – the period in which human activity profoundly shapes the environment – has taken an important step closer to general acceptance. A working group of scientists has been mulling over the subject for seven years. This week 30 of its 35 members recommended adding the Anthropocene to our standard geological timescale. The ultimate decision rests with the International Commission on Stratigraphy.