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Scientists have for the first time detected gravitational waves ripples in the fabric of space-time produced by the collision of a neutron star and a black hole. This finding confirms that there are neutron star-black hole systems and will help answer many questions about the cosmos, from star formation to the expansion rate of our universe. Gravitational waves are produced when celestial objects collide and the ensuing energy creates ripples in the fabric of space-time which carry all the way to detectors on Earth. The reverberations from the two celestial objects were picked up using a global network of gravitational wave detectors, the most sensitive scientific instruments ever built, according to the researchers from UK’s Strathclyde University. The university is part of the international network of scientists, the LIGO Scientific Collaboration. On January 5 this year, the Advanced LIGO detector in Louisiana, US, and the Advanced Virgo detector in Italy picked up the final throes of the death spiral between a neutron star the collapsed core of a massive supergiant star, and a black hole as they circled ever closer and merged together. This is the first time scientists have seen gravitational waves from a neutron star and a black hole Previous gravitational wave detections have spotted black holes colliding, and neutron stars merging but not one of each, the researchers said.