PULSE@Parkes countdown to New Year 2009
Pulsars as clocks
The animation shows a typical pulsar that rotates approximately once every few seconds. The trace at the bottom of the animation represents the strength of the radio signal as the pulsar beam sweeps over us on Earth. The sound that you hear is the pulsar's radio signal converted into an audio signal.
Pulsar animation: M. Kramer (University of Manchester)
Pulsars are arguably the most stable clocks in the universe. Like light-houses in space, everytime a pulsar rotates we see a flash of radio light that can be detected using large telescopes on Earth. By studying these flashes of light astronomers can study whether our atomic clock time scales that we use for time keeping are accurate or whether they need correction.
For the PULSE@Parkes project, Australian high school students carry out observations of a large sample of pulsars. A pulsar known as PSR J0437-4715 is being used to count down to New Year 2009. This pulsar rotates approximately 600 times more rapidly than the pulsar shown in the animation above and is too fast to show in a similar animation. The number at the top of this page indicates how many more rotations this pulsar will undergo before New Year 2009. The pulsar research being carried out at the Australia Telescope National Facility may allow this pulsar to be used to test atomic clocks on Earth in the near future.