It's usually the stuff of movies - like the 90s classic movie Armageddon but at 7.21pm NZT, NASA will launch a spacecraft in an attempt to alter the course of an asteroid.
In what's being called the Double Asteroid Redirection Test, or DART, a rocket will be sent towards an asteroid called Didymos and its small moon, Dimorphos.
It will intentionally collide with that small moon with the aim of changing its path, so NASA can understand what needs to be done if Earth is ever faced with its very own Armageddon moment.
Corin Dann spoke to NASA's Proximity Working Group and Science Operations Lead for DART Dr Olivier Barnouin.