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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2010年3月3日，“卡西尼”号与土卫十二“海伦”这颗形状不规则的卫星亲密接触。

On March 3, 2010, Cassini got up close and personal with Helene, an irregularly shaped moon of Saturn.

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