Astronomers at Australia’s national radio and optical observatories will watch as a probe released from a spacecraft slams into a comet about 133 million km away at a speed of nearly 37,000 km/h (10.2 km per second).
The cosmic demolition derby takes place about 4pm AEST on 4 July when the comet, Tempel 1, will be most easily seen from the mid-Pacific.