The international collaboration LIGO (Laser Interferometer Gravitational-wave Observatory) has announced a third detection of gravitational waves, ripples in the fabric of space-time . As in the two previous detections, the gravitational waves were generated from the merger of two distant black holes that formed a larger one . The black hole that emerged from the collision has a mass equivalent to 49 times that of the Sun , which places it right between the masses of the two black holes previously detected by LIGO, which were 62 and 21 solar masses, respectively.
According to David Shoemaker, spokesman for LIGO, where more than 1,000 scientists work, this detection is a new confirmation of the existence of stellar black holes with more than 20 solar masses . These are objects whose existence we did not know until LIGO found them. It is remarkable that such strange and extreme events can be proven that took place billions of years ago and billions of light years from our planet. All the researchers from the LIGO collaborations and the European Virgo work to sort all the pieces they find.
The new detection occurred during LIGO’s current observing work season, which began on November 30, 2016 and runs through the summer. LIGO is a scientific collaboration with members located all over the world. Observations are carried out by means of two detectors located more than 3,000 km apart. One of them is in Hanford, in the state of Washington, in the northwestern United States, and the other in Livingston (Louisiana), in the southeast.
The latest detection is the farthest of the three made so far, lying almost 3 billion light-years away, up from 1.3 and 1.4 billion light-years for the previous two detections. The new observation also provides clues to the spin directions of black holes. As the two black holes spiral around each other, they also rotate on their own axes, just as a pair of individual ice skaters would do while also evolving around each other.
Caption: Recreation of the merger of the two black holes from the NEW LIGO detection.
IMAGE CREDIT: Numerical-relativistic Simulation: S. Ossokine, A. Buonanno (Max Planck Institute for Gravitational Physics) and the Simulating eXtreme Spacetime project Scientific Visualization: T. Dietrich (Max Planck Institute for Gravitational Physics), R. Haas (NCSA)
