The greatest threat to life on Earth may come from space

Asteroids and space debris could wreak untold devastation on the planetNext year, Nasa will launch what all involved hope will be the most impactful space mission to date. The Double Asteroid Redirection Test (Dart) is designed to smash headlong into its target. It’s an attempt to deflect an asteroid as a test of what to do if we spot a similar space rock on a collision course with our planet.It’s hardly news we want to hear at a time of so many domestic problems, but the threat from