Lucky Planet Quotes

“Burrator Reservoir, in south-west England’s Dartmoor National Park, is a good place to start. My university department takes its new geology students to this spot every autumn to give them their first taste of intrusive volcanic rocks – rocks formed when molten magma flows through the Earth’s cool upper crust slowly enough to solidify before it breaks through to the surface. The uplands of Dartmoor exist only because the resulting granite, deposited near the beginning of the Permian Period 290 million years ago, is more resistant to erosion than the softer rocks of the surrounding, low-lying countryside. Our students first see the granite in a small abandoned quarry, just south of Burrator Reservoir, and this location illustrates nicely many crucial components of the Earth’s climate system. The geological processes operating in this area act like a thermostatically controlled air conditioning system and, together with similar processes occurring in many places across the world, help keep temperatures on our planet roughly constant and, hence, suitable for life.”
― David Waltham, Lucky Planet: Why Earth is Exceptional-and What That Means for Life in the Universe

“A period of renewed heavy bombardment began as large objects were deflected into the inner solar system by recently formed outer planets. The evidence for this is visible on any clear moonlit night. The large, dark marks that make up the features of ‘the man in the Moon’ are easily visible to the unaided eye. Our ancestors also saw these features and believed them to be seas on the surface of the Moon. In reality, they are enormous impact craters – and analysis of the rocks, brought back by the Apollo astronauts, shows that these craters formed 3.8 billion years ago. It seems obvious that similar-sized impacts must have also happened on Earth and that these would have sterilised the surface so that life only just clung on in the deep, dark places of the world. Much of the atmosphere and ocean would have been blasted off our planet in these cataclysms, to be slowly replaced, over millions of years, by exhaust from volcanoes.”
― David Waltham, Lucky Planet: Why Earth is Exceptional-and What That Means for Life in the Universe