{"id":52135,"date":"2017-10-16T09:00:12","date_gmt":"2017-10-16T14:00:12","guid":{"rendered":"https:\/\/uwm.edu\/news\/?p=52135"},"modified":"2017-10-19T10:23:23","modified_gmt":"2017-10-19T15:23:23","slug":"uwm-physicists-immersed-in-first-ever-detection-of-neutron-star-collision","status":"publish","type":"post","link":"https:\/\/uwm.edu\/news\/uwm-physicists-immersed-in-first-ever-detection-of-neutron-star-collision\/","title":{"rendered":"51ÁÔÆæ physicists immersed in first-ever detection of neutron star collision"},"content":{"rendered":"

Just two weeks after the 2015 discovery of gravitational waves won a Nobel Prize, astronomers are back with another groundbreaking discovery. They\u2019ve spotted gravitational waves again, but this time with an optical counterpart. It\u2019s the first time astronomers have observed light from a gravitational wave source.<\/p>\n

Previous detections involved the collision of black holes, which give off no light. This time, it\u2019s neutron stars, which do.<\/p>\n

UW-Milwaukee members of the LIGO\/Virgo Collaboration were instrumental in detecting the signal from the LIGO (the Laser Interferometer Gravitational-Wave Observatory) detectors and analyzing the gravitational waves from the collision. In addition, 51ÁÔÆæ astronomers who are not members of the LIGO team played a major role in the discovery and making observations in the electromagnetic radiation.<\/p>\n

\u201cAs exciting as first discovery of gravitational waves was, this event shows the great promise of LIGO, in terms of both broadening and deepening our understanding of the universe,\u201d said Patrick Brady, director the Leonard E. Parker Center for Gravitation, Cosmology and Astrophysics and a member of the LIGO team at 51ÁÔÆæ. \u201cWe\u2019re thrilled about the science we at LIGO will be able to do, but also excited by the discoveries made possible for our colleagues working in the electromagnetic spectrum.\u201d<\/p>\n

On Aug. 17, a LIGO scientist noticed that the computer had flagged an interesting signal that had the character of a collision between orbiting neutron stars, but it came from only one of the two LIGO detectors.\u00a0 Normally such a detection requires both detectors, but the scientist noticed that NASA\u2019s Fermi Gamma-ray Space Telescope also detected a burst of gamma rays at the same time.\u00a0 These signals were unlikely to be coincidences, and LIGO soon found the signal in the second LIGO detector. The Virgo detector in Italy made it possible to determine the location of the event with relatively high precision.<\/p>\n

The gravitational scientists notified their astronomical colleagues who, using a new catalogue of relatively nearby galaxies, found the explosion only 10 hours after it happened in NGC 4993, a galaxy about 130 million light-years away in the constellation Hydra. The identification allowed observations of the event in a wide array of wavelengths, employing traditional optical observatories, radio telescopes and satellites.\u00a0 All told, hundreds of astronomers around the world, using telescopes on all seven continents and in space, followed this event frantically as the source disappeared into twilight.\u00a0 And 51ÁÔÆæ was right there in the middle of it.<\/p>\n

Scientifically, the observations promise to:<\/p>\n