A radioactive spacecraft thought to be on a collision course with Queensland sparked an emergency response stretching from Brisbane to Washington in 1996. But the public knew nothing of it.

The Hollywood-style reaction was ramped up, and back down, within hours amid fears the craft could smash into a heavily populated area in South East Queensland, according to then-premier Rob Borbidge.

It was 19 years ago and Russia had just attempted to launch the Mars 96 spacecraft to send orbiters and surface craft to explore Mars.

The launch failed and the plutonium-fuelled probe came hurtling back to earth.