GW170817 was the first detection of a neutron star merger with gravitational waves.

The detection of a spatially coincident weak burst of gamma-rays (GRB 170817A) 1.7 s after the merger constituted the first electromagnetic detection of a gravitational wave source and established a connection between at least some cosmic short gamma-ray bursts (SGRBs) and binary neutron star mergers.

A fast-evolving optical and near-infrared transient (AT 2017gfo) associated with the event can be interpreted as resulting from the ejection of ∼0.05 M_⊙ of material enriched in r-process elements, finally establishing binary neutron star mergers as at least one source of r-process nucleosynthesis.

Radio and X-ray observations revealed a long-rising source that peaked ∼160,d after the merger. Combined with the apparent superluminal motion of the associated very long baseline interferometry source, these observations show that the merger produced a relativistic structured jet whose core was oriented ≈20 deg from the line of sight and with properties similar to SGRBs. The jet structure likely results from interaction between the jet and the merger ejecta.

The electromagnetic and gravitational wave information can be combined to produce constraints on the expansion rate of the Universe and the equation of state of dense nuclear matter. These multimessenger endeavors will be a major emphasis of future work.

GW170817 是首次探测到具有引力波的中子星合并。

合并后 1.7 秒对空间重合的伽马射线微弱爆发 (GRB 170817A) 的探测构成了对引力波源的首次电磁探测，并在至少一些宇宙短伽马射线爆发 (SGRB) 和双星之间建立了联系中子星合并。

与该事件相关的快速演化的光学和近红外瞬变 (AT 2017gfo) 可以解释为喷射约 0.05 M _⊙富含r 过程元素的物质，最终确定双中子星合并为至少一个r-过程核合成的来源。

无线电和 X 射线观测揭示了一个长期上升的源，在合并后达到 160,d 的峰值。结合相关的超长基线干涉测量源的明显超光速运动，这些观察表明合并产生了一个相对论结构射流，其核心与视线的方向相差约 20 度，并且具有类似于短暴的特性。射流结构可能是由射流和合并喷射物之间的相互作用产生的。

电磁波和引力波信息可以结合起来，对宇宙的膨胀率和致密核物质的状态方程产生约束。这些多信使的努力将是未来工作的重点。