中国天文学家的又一篇Science

作者
徐烨（南大天文系/上海台）、Mark Reid（哈佛-史密松森天体物理中心）、郑兴武（南大天文系）、Karl Menten（马普）

The Distance to the Perseus Spiral Arm in the Milky Way
Authors: Y. Xu (NJU, Cfa, Shao), M. J. Reid (CfA), X. W. Zheng (NJU), K. M. Menten (MPIfR)
Comments: 19 pages, 4 figures, Science Express December 8, 2005

   We have measured the distance to the massive star-forming region W3OH in the Perseus spiral arm of the Milky Way to be 1.95 $\pm$ 0.04 kilo-parsecs ($5.86\times10^{16}$ km). This distance was determined by triangulation, with the Earth's orbit as one segment of a triangle, using the Very Long Baseline Array. This resolves a long-standing problem of a factor of two discrepancy between different techniques to determine distances. The reason for the discrepancy is that this portion of the Perseus arm has anomalous motions. The orientation of the anomalous motion agrees with spiral density-wave theory, but the magnitude is somewhat larger than most models predict.

http://www.arxiv.org/abs/astro-ph/0512223

赞一个~~

我们已经测定了我们到银河系英仙旋臂中大质量的恒星形成区W3OH的距离,为1.95+-0.04kpc(5.86*10^16km).这个距离是使用三角测量法确定的,用地球轨道做为三角形的一条边,使用甚长基线射电望远镜阵(确定其位置?).这就解决了一个长期存在的问题,即使用不同的方法测定的距离之间存在差异.存在差异的原因是英仙旋臂的一部分存在无规则运动.无规则运动的方向与旋臂密度波理论预言的一致,但是大小比大多数模型预言的都要大一些.

http://amateur.lamost.org/bootes/bbs/viewtopic.php?t=48818
就是这个啊，觉得我们新闻记者写的不如外国同行吗？

很好啊