The big question: By detecting these gravitational waves on Earth, scientists can work backwards to find out more about what has created these ripples, allowing us to better understand some of the most extreme objects in the universe.
"The entire astrophysics community is very happy to have already attended 5 candidate events in four weeks."
– LIGO astrophysicist, Jess McIver, said Thursday at a press conference
Details: Three of the gravitational wave signals would come from two black holes combined, the fourth would have been emitted by colliding neutron stars. The fifth, and perhaps the most exciting, seems to come from the fusion of a black hole and a neutron star.
- If confirmed, it will be the first black star-hole neutron fusion ever documented.
The five signals still need to be confirmed by a follow-up analysis.
How it works: LIGO and Virgo are able to detect these gravitational waves thanks to a very precise instrumentation. When a gravitational wave crosses the terrestrial part of space, each atom deforms slightly.
- A laser travels the arms of the three L-shaped detectors of LIGO and Virgo. Once the laser touches the end of the detector, a mirror returns light to the center.
- If no gravitational wave has passed through, the beams of light must return at the same time to the curvature of the L, but in case of disagreement, a gravitational wave may have been observed.
And after: Unlike previous observation campaigns, both observatories began to publish their detections in real time, allowing other observatories to make follow-up observations.
