根据剑桥大学研究人员参与的一项新研究，在宇宙可观测到的最早期的已知星系之一似乎在以低于今天银河系速度的四分之一旋转。

One of the most distant known galaxies, observed in the very earliest years of the Universe, appears to be rotating at less than a quarter of the speed of the Milky Way today, according to a new study involving University of Cambridge researchers.

对于这项发表在《天体物理学杂志快报》上的研究，一个国际研究小组分析了来自名为 MACS1149-JD1 (JD1) 的星系数据，这些数据来自阿塔卡马大型毫米波/亚毫米波阵列 (ALMA) 的观测数据，该阵列由位于智利的一些射电望远镜组成。

For the study, published in The Astrophysical Journal Letters, an international team of researchers analysed data from a galaxy known as MACS1149-JD1 (JD1), obtained from observations by the Atacama Large Millimeter/submillimeter Array (ALMA), an assembly of radio telescopes in Chile.

由早稻田大学的 Tsuyoshi Tokuoka 领导的研究人员发现了光波长度的细微变化，表明JD1星系的一部分正在远离我们，而其他部分正在向我们移动。从这些变化中，他们得出结论，JD1星系呈圆盘状，并以每秒 50 公里的速度旋转。相比之下，今天的银河系以每秒 220 公里的速度自转。

The researchers, led by Tsuyoshi Tokuoka of Waseda University, found subtle variations in the wavelengths of the light indicating that parts of the galaxy were moving away from us while other parts were moving towards us. From these variations, they concluded that the galaxy was disc-shaped and rotating at a speed of 50 kilometres a second. By contrast, the Milky Way, at the Sun’s position, rotates with a speed of 220 kilometres per second today.