Many, though, form a ring like Saturn's at a distance of 36,000km, the place at which an object takes 24 hours to orbit the Earth and thus hovers continuously over the same point of the planet.
尽管,许多卫星在36000千米处形成一个类似土星光环的环,但这个高度的卫星都需要花费24小时绕地球一圈。因此,它们一直在地球上空的同一点盘旋。
The yellow line shows the orbit of the moon Phoebe, which circles through the new found ring, represented in tan.
黄线表示土卫九的轨道,其轨道穿过新发现的以黄褐色表示的环。
Both the ring and Phoebe orbit in the opposite direction of Saturn's other rings and most of its moons, including Titan and Iapetus.
新环和土卫9的运行方向与土星主光环以及包括较大的土卫六和土卫八的大部分卫星的方向相反。
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