这些照片都是在太阳动力学观测站上拍摄到的，它目前是研究太阳这个天体中，最先进的航天器。
The pictures were taken by the Solar Dynamics Observatory (SDO), which is the most advanced spacecraft ever designed to study the Sun.
双重星系或天体系统，用动力学方法测定其质量时，观测到的视向速度和距离间距，都是各自值的投影值，可用统计方法，求出一个关于它们的平均投影因子。
Both of the observed radial velocity and separation being projective values, in order to determine the mass of binary galaxies the average projection factor may be derived by a statistical method.
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