银河系英仙臂的距离

Distance of the perseus spiral arm in the Milky Way

以地球轨道半径为基线,借助目前世界上最高分辨率的甚长基线干涉阵(VLBA),通过测量英仙臂中大质量恒星形成区W3OH的三角视差,得到了银河系中距离太阳最近的英仙臂的距离为1.95±0.04千秒差距(5.86×1016km).这个工作解决了天文学中关于英仙臂距离的长期争论,说明英仙臂显示强的运动学反常.

The distance to the massive star - forming region W3OH in the Perseus spiral ann of the Milky Way has been measured to be 1.95 ±0.04 kiloparsecs （5.86 × 10^16 km）, determined by triangulation using the Very Long Baseline Array with the Earth＇s orbit as one segment of a triangle. This resolves a long - standing discrepancy of a factor of two. The reason for the discrepancy is that this portion of the Perseus ann has anomalous motions.