Gravitational Waves Possibly From Two Colliding Neutron Stars Detected
On April 25 gravitational waves thought to have originated with a collision between two neutron stars were detected. The instruments that detected the gravitational waves include the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the European Virgo detector. The two instruments registered the gravitational waves on April 25 and one day later the LIGO-Virgo network spotted another candidate source for the gravitational waves.
That second candidate source suggested that the gravitational waves might have been the result of the collision of a neutron star and a black hole, an event that was never witnessed before. The team says that it is curious about the April 26 candidate, but the signal it received is rather weak.
Scientists say that its like listening to someone whisper a word in a busy cafe. The team says it will take time to reach a conclusion on that candidate. The team says that the discoveries show that LIGO-Virgo collaboration is realizing its potential and is producing discoveries that were once thought to be impossible.
The new discoveries came only a week after LIGO and Virgo were turned back on. The instruments resumed operations on April 1 after being shut down for upgrades meant to increase their sensitivities to gravitational waves. Gravitational waves are described as ripples in time-space. With their upgrades, the detectors can survey larger portions of the universe than before.
The Virgo detector can cover the sky 90% of the time and gather useful data. The LIGO-Virgo network has spotted three possible black hole mergers along with the two new neutron star candidates. The instruments were responsible for the first-ever detected gravitational waves in 2015. The instruments have discovered evidence of at least two neutron star mergers, 13 black hole mergers, and one possible black hole-neutron star merger.