P455 - Timing & geodetic precession in the double pulsar

Brief description Pulsars are incredible compact residues generated in the supernova explosion of dying massive stars. These sorts of stellar corpses concentrate the mass of one and a half Suns in a sphere just 25 km across. They are so dense that a spoonful of their matter would weight 100 billion tons on Earth! Thanks to their rapid rotation - the fastest spins 716 times in a second - and extreme magnetic fields - 1000 billion times that of Earth - pulsars emit collimated beams of radio waves. This makes them appear as cosmic light-houses: one time per rotation their radio beacons cross the line of sight to Earth and astronomers register, through big radio telescopes, a pulse of radio waves. This project studies a unique pair of pulsars, known as the Double Pulsar. The system, discovered at Parkes in 2003, is the only one known to have two pulsars orbiting around one another. Thanks to the precision of their clock-like signals and to the extreme conditions in the binary system, the Doube Pulsar allows astronomers to test Einstein's theory of general relativity with unprecedented precision. The tests performed so far allow us to say that Einstein was right at least at the 99.99% level.