Dust and other debris would rise into the atmosphere on Bennu striking Earth, blocking out the Sun and cooling the planet to devastating effect.

There would be only seconds to prepare before the fireball strikes. A ‘city-destroying’ asteroid is currently on a path towards Earth and could hit as soon as 2032. Now experts have modelled what the possible impact of 2024 YR4 – equal to 15,

On the world's first Asteroid Day, Nina Burleigh discovers that Nasa has already commissioned a team of 'planetary defenders' for whom the question is not if but when