Closer inspection by NASA's Hubble Space Telescope reveals that these spots are actually a rare alignment of three of Jupiter's largest moons - IO, Ganymede, and Callisto - across the planet's face.
美国宇航局的哈勃太空望远镜近的距离观察发现，这些斑点实际上是横跨在木星表面上，很少见到的3个最大卫星(木卫1，木卫3，木卫4)的直线排列。
In this paper, the principle and procedure of alignment of Cassegrain and coude optical systems for 2.16m astronomical telescope are described.
叙述了2.16米天文望远镜卡焦及折轴光学系统的调整原理与具体步骤。
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