Test drive of planetary defence system aims to provide data on how to deflect asteroids away from Earth

That’s one large rock, one momentous shift in our relationship with space. On Wednesday, Nasa will launch a mission to deliberately slam a spacecraft into an asteroid to try to alter its orbit – the first time humanity has tried to interfere in the gravitational dance of the solar system. The aim is to test drive a planetary defence system that could prevent us from going the same way as the dinosaurs, providing the first real data about what it would take to deflect an Armageddon-inducing asteroid away from Earth.

Our planet is constantly being bombarded with small pieces of debris, but these are usually burned or broken up long before they hit the ground. Once in a while, however, something large enough to do significant damage hits the ground. About 66m years ago, one such collision is thought to have ended the reign of the dinosaurs, ejecting vast amounts of dust and debris into the upper atmosphere, which obscured the sun and caused food chains to collapse. Someday, something similar could call time on humanity’s reign – unless we can find a way to deflect it.