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。
Spitzer viewed the ring edge-on from its Earth-trailing orbit around the sun.
Spitzer卫星在围绕太阳运转的地球轨道上观测到了环的侧面。
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