NASA/JPL-Caltech
Asteroid 2018 CB is set to safely pass the Earth today, around 63,000 kilometres above our heads. But if a deadly asteroid was set to hit the planet, humanity would have to scramble to conduct the world’s riskiest experiment. Since we have never attempted to shove a space rock off its course, any defence efforts would be an untested prospect.
It’s not that people haven’t come up with ideas – like chucking a whole bunch of nuclear weapons at an incoming threat – but with limited budgets devoted to asteroid …