英语听力：自然百科:行星旅行指南 火星(31)（在线收听）

Spotting these rings from a backyard telescope is a treat.

从后院的望远镜观察这些土星环是一种不错的选择。

In an instant, they can all but disappear when Saturn tilts toward the sun.

在一瞬间, 当土星朝太阳倾斜他们会全部消失。

The overwhelming thing that a US space tourist would be struck by is how incredibly thin they are.

令人震惊的是美国的太空游客们也将会因其极为稀薄而受困。

They are no thicker than about one or two stories in a modern day building.

他们和当代建筑的一层或者两层相比不是很厚。

Interested in seeing for yourself? Strap in, space travelers, it's quite a ride.

为看到自己感兴趣吗?系好安全带，太空旅行者们,这是一次非常快的旅程。

After seven years and a billion miles of space, the Cassini-Huygens spacecraft faces its greatest challenge on June 30th, 2004.

经过七年和十亿英里的太空旅程,在2004年6月30日，卡西尼·惠根斯航天器面临最大的挑战。