Are we doing enough to save Earth from a devastating asteroid strike?

Nasa’s Sart spacecraft deliberately crashed into an asteroid in 2022 to alter its trajectory Photograph: Alamy

It is a scenario beloved of Hollywood: a huge asteroid, several miles wide, is on a collision course with Earth. Scientists check and recheck their calculations but there is no mistake – civilisation is facing a cataclysmic end unless the space rock can be deflected.

It may sound like science fiction, but it is a threat that is being taken seriously by scientists.