Gravitational-Wave Astronomy LARGE SCIENTIFIC PROJECT
relativity had been incorrect, the orbital dynamics of the objects, and therefore the emitted waveform, would have differed. But the match was remarkably precise.
Virgo joins LIGO: The era of multimessenger astronomy
Figure 4. GW150914, the first gravitational-wave detection Source: https:// en. wikipedia. org / wiki / First _ observation _ of _ gravitational _ waves
The detection was published by the LIGO and Virgo Collaborations, comprising more than a thousand scientists. With that detection( GW150914) gravitational-wave astronomy officially began [ 12 ]. This first signal not only enabled the first direct detection of gravitational waves, but also demonstrated that black holes can exist in binary systems and can merge within the age of the Universe. Moreover, general relativity was tested in a completely new regime: that of strong gravitational fields. The detected waveform was compared to a combination of analytical models( valid especially during the inspiral phase) and numerical simulations( necessary during the merger and ringdown phases). If general
In 2017, Virgo officially joined LIGO in the second observing run( O 2). On August 14, the first triple detection- with signals observed by both LIGO detectors and Virgo- was recorded: a binary black hole merger( GW170814) [ 13 ]. This event marked a fundamental step forward, demonstrating the power of triangulation in improving the sky localization of gravitational-wave sources. Just three days later, on August 17, the gravitational-wave community observed a truly historic event: GW170817, the first detection of a binary neutron star merger [ 14 ]. The gravitational-wave signal was emitted first, followed 1.7 seconds later by a short gamma-ray burst detected by NASA’ s Fermi and ESA’ s INTEGRAL satellites. The combined observation enabled an extremely precise
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