It has already added more than 200 new pulsars to the nearly 800 known when the survey began about a year ago. By the end of the survey, in around a year or so's time, it is expected that over 600 additional pulsars will have been discovered. A pulsar is the collapsed core of a massive star that has ended its life in a supernova explosion. Weighing more than our Sun, yet only 20 kilometres across, these incredibly dense objects produce beams of radio waves which sweep round the sky like a lighthouse, often hundreds of times a second. Radio telescopes receive a regular train of pulses as the beam repeatedly crosses the Earth so the objects are observed as a pulsating radio signal.
Pulsars make exceptional clocks, which enable a number of unique astronomical experiments.
Very precise timing observations of systems in which a pulsar is in orbit around another neutron star have been able to prove the existence of gravitational radiation as predicted by Albert Einstein and have provided very sensitive tests of his theory of General Relativity - the theory of gravitation which supplanted that of Isaac Newton. The team are hoping that they might soon discover a neutron star in orbit around a black hole. If such a pair were to be found, it would give us the ability to learn far more about black holes, which are such elusive and enigmatic objects. Nevertheless, even surveys like this can only find a fraction of the 300,000 pulsars thought to exist in our galaxy. Dr Dick Manchester, the leader of the Australian group within the pulsar team.