Nasa made a big announcement last week: seven Earth-sized planets orbit a star 40 light-years away and 3 of them are in the planet's habitable zone. Why should we care?
Why care about exoplanets?
We’re bracing for impact
66 million years ago, an object the size of Mount Everest crashed down into the sea near modern-day Mexico and radically changed the world. It sent a cloud of dust and molten rock into the air that blocked out the sun, which killed loads of plants, which big herbivores like Triceratops needed, which large carnivores like T. Rex …
Jon Farrow 