A press release says that these improvements will allow LIGO/Virgo to “listen deeper into the cosmos than ever before.” Raw data processing has been improved, as well as how glitches or disturbances are dealt with. The new detections in the catalogue result from improvements in the LIGO/Virgo collaboration. There are signals from mergers with less massive objects like GW190814 but we don’t know for sure whether these are black holes.” One had the mass of 6 Suns, the other that of 9 Suns. “GW190924_021846 certainly is from the merger of the two lightest black holes we’ve seen so far. Unfortunately the signal is rather faint, so we cannot be entirely sure,” explains Serguei Ossokine, a senior scientist at AEI Potsdam. “One of our new discoveries, GW190426_152155, could be a merger of a black hole of around six solar masses with a neutron star. A pair of the detections were from the mergers of low-mass objects. The new catalogue contains some surprises. Image Credit: LIGO Virgo Collaboration / Frank Elavsky, Aaron Geller / Northwestern A selection of black holes (violet) and neutron stars (yellow) discovered by electromagnetic observations is shown for comparison. Each merger of a binary system corresponds to three compact objects shown: the two merging objects and the result of the merger. The diagram shows black holes (blue), neutron stars (orange) and compact objects of unknown nature (grey), which were detected by their gravitational-wave emission. The mergers of compact objects discovered so far by LIGO and Virgo (in O1, O2 and O3a). Eventually, the facilities were upgraded, and in 2015 they detected their first merger. When they were observing between 2002 to 2010, they detected no gravitational waves and no mergers. LIGO’s collaborative partner is Virgo, an interferometer located in Italy. LIGO is actually two facilities in the US, both built and operated by Caltech and MIT. LIGO stands for Laser Interferometer Gravitational-Wave Observatory. The new infographic displays the black holes, neutron stars, mergers, and the other uncertain compact objects behind some of them. The collaboration has released a new catalogue of discoveries, along with a new infographic. Since then, the LIGO/Virgo collaboration has detected many of them. It took about one hundred years, but scientists finally observed these mergers and their gravitational waves in 2015. But regardless of the minds behind it, the theory predicted black holes, neutron stars, and the gravitational waves from their mergers. Einstein gets the credit for the theory because of his paper published in 1915, even though other scientists’ work helped it along. This eliminates an important layer of the many uncertain assumptions affecting the predictions of merger detection rates with the gravitational wave detectors aLIGO/aVirgo.The Theory of Relativity predicted the existence of black holes and neutron stars. We conclude that the predictions are, for practical purposes, robust against uncertainties in the initial conditions concerning binary parameters with exception of the IMF. No significant changes in the distributions of final component masses, mass ratios, chirp masses and delay times are found. An exception is the uncertainty in IMF (variations by a factor of 6 up and down). The uncertainties do not significantly affect (within a factor of 2) our predictions of double compact object merger rates. With the advanced Gravitational Wave detectors coming online, astrophysicists hope to soon detect the signal from the merger of two neutron stars (NS) or black holes (BH). We investigate the impact of the new constraints on the birth properties of massive stars on the predicted rates for NS and BH mergers. Despite the large changes with previous assumptions (larger binary fraction, stronger preference for very tight systems), we only find an increase of less than a factor 2 (insignificant compared with evolutionary uncertainties of typically a factor 10-100).