Listening to the Universe
Gravitational wave astronomy will open an entire new window on our Universe. Gravitational waves are produced by violent events in the distant universe, for example by the collision of two black holes or by the cores of supernova explosions. They are emitted by accelerating masses much in the same way as radio waves are produced by accelerating charges – for example, such as electrons in antennas. These ripples in the space-time fabric travel to Earth, bringing with them information about their violent origins and about the nature of gravity that cannot be obtained by other astronomical tools.
However, the changes in distance caused by gravitational waves are tiny: even the gravitational wave produced by a powerful event in our vicinity, like a supernova explosion within the Milky Way, changes the total distance between Earth and Sun only by about the diameter of a hydrogen atom - and that merely for several thousandths of a second. For shorter distances the effect is correspondingly smaller: when measuring over a distance of only one kilometer a change of a thousandths of the diameter of a proton has to be detected to determine the passing of a gravitational wave. This is the effect GEO600 will measure. The great challenge is to get rid of the many disturbances, like air pressure and temperature fluctuations as well as seismic vibrations of all sorts, that would conceal a signal.
About the team