Researchers look with high hopes to gravitational wave astronomy, but there’s one slight problem—though gravitational waves have been predicted, they haven’t yet been directly detected. Remember that GWs only weakly interact with matter, so they are extremely difficult to detect.

Modern day gravitational wave detector projects in the U.S. and abroad are preparing to look for the waves’ tidal characteristics: stretching and squeezing along different axes as they change the distance between widely separated masses. Thus far, the only sources of gravitational waves bright enough to be detected are violent astrophysical events, but sources of interests include:

- Coalescing binaries: Binary systems consisting of either neutron stars or black holes can orbit each other, begin to fuse, and ultimately merge.

- Stellar core collapse: The collapse of stars in the form of supernovae is theorized to be a source of strong gravitational wave emission.

- Dynamics of the early universe: An all-sky background of gravitational wave “noise”, similar to the cosmic microwave background, may aid in the understanding of the infant universe and how it has evolved.

For more information on current projects, visit:

LISA : the Laser Interferometer Space Antenna

LIGO : the Laser Interferometer Gravitation Wave Observatory

TAMA 300 (Japan)

VIRGO (France/Italy)

GEO 600 (Germany/Great Britain)

ACIGA (Australia)