Gravity Waves from Black Holes Observed August 14, 2017

Since the first detection of gravitational waves by the LIGO interferometers on September 14, 2015, the advanced Virgo interferometer has been added to the detection system. That addition was very valuable when another gravitational wave event was observed on August 14, 2017. It was described by the APS News as follows: "The signal, which was observed on August 14, 2017, comes from a merger of a black hole 30.5 times the mass of the sun with another black hole 25.3 times the mass of the sun. The event occurred 540 megaparsecs from Earth, or about 1.8 billion light years away. Because the gravitational wave detection network involves three detectors, the researchers have been able to narrow down the location of the signal source by a factor of nearly 20 compared with LIGO's previous detections."

自2015年9月14日LIGO干涉仪首次探测到引力波以来，先进的Virgo干涉仪已被加入探测系统。当2017年8月14日又观测到一次引力波事件时，这一新增设备显得尤为宝贵。据APS新闻报道，该事件描述如下：‘2017年8月14日观测到的信号来自两个黑洞的合并，其中一个黑洞的质量是太阳的30.5倍，另一个是太阳的25.3倍。该事件发生于地球1.8十亿光年之外，即540兆秒差距处。由于引力波探测网络涉及三个探测器，研究人员能够将信号源位置确定性提高到LIGO以往探测结果的近20倍。’

"The signal was first detected by the LIGO detector in Louisiana, then 8 milliseconds later by the LIGO detector in Hanford, then 6 milliseconds after that, by the Virgo detector."

信号首先由路易斯安那州的LIGO探测器检测到，随后在8毫秒后，由汉福德的LIGO探测器检测到，再过6毫秒，由Virgo探测器检测到。