土卫三号仅为左下方的一个小片。

Tethys is a mere sliver below left.

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科学家们认为土卫二冰火山的活跃时间只占其寿命时间的1%到20%，幸运的是，卡西尼号飞越土卫二的时候正好赶上了喷发期。

Scientists believe the cryovolcanism on Enceladus has only been active during 1 to 20 percent of its existence. We’re glad Cassini caught it in an eruptive phase.

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从土卫二号北半球的这个角度来看，大型坑洞以及坑洞地带是非常罕见的。

Craters and cratered terrains are rare in this view of the southern region of the moon's Saturn-facing hemisphere.

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