Manx comets, like their tail-wagging brethren, come from the Oort cloud.

马恩岛猫彗星，和它们带有慧尾的兄弟一样，来自奥尔特云。

Beyond the fringes of the Kuiper belt is the Oort Cloud.

在柯伊伯带的边缘之外是奥尔特云。

The Oort Cloud is the origin of long period comets.

奥尔特云是长周期彗星的起源之处。

Comets move in the Oort Cloud in the Kuiper Belt, which is beyond the planet Neptune.

慧星在柯伊伯带的奥尔特云里移动，远在海王星之外。

Scientists believe that short-period comets come from the Kuiper Belt, and long-period comets come from the Oort Cloud.

科学家相信，短周期彗星来自于柯伊伯带，而长周期彗星则来自于奥尔特云。

While we know of lots of Kuiper Belt Objects, we don't know of any Oort Cloud objects for sure.

虽然我们知道很多柯伊伯带的物体，但我们还不知道任何奥尔特云中确定的物体。

From beyond Neptune, out in the Kuiper Belt and Oort Cloud.

来自海王星以外的柯伊伯带和奥尔特云。

Comets made of ice were redirected from the Oort Cloud and the Kuiper Belt.

由冰构成的彗星从奥尔特云和柯伊伯带重新定向。

If that sounds like a lot, get this: the Oort Cloud, surrounding the solar system, may have trillions of icy bodies in it.

如果这听起来很多，那么听听这个：围绕太阳系的奥尔特云中可能有数万亿的冰体。

The more reclusive long-period comets among them the recent visitors Hale-Bopp and Hyakutake come from the much more distant Oort cloud, about which more presently.

比较长命的彗星其中有最近光顾的海尔－博普彗星和百武彗星产生于遥远得多的奥尔特云，我们过一会儿就会谈到这个问题。

ISON started its journey thousands of years ago in the Oort Cloud, a spherical collection of icy bodies about one light-year from the sun.

几千年前，爱森彗星从奥尔特云——距离太阳约1光年的一个球形冰体集合——出发开始了它的旅程。

From there, we'd speed to the inner limits of the Oort Cloud - the beginning of the edge of our Solar System.

从那里，我们将加速到达奥尔特云的内部边界——我们太阳系边缘的起点。

About all that can be said with confidence about the Oort cloud is that it starts somewhere beyond Pluto and stretches some two light-years out into the cosmos.

关于奥尔特云，有把握的只能说到这种程度：它始于冥王星以外，向宇宙里伸展大约两光年。

We know there's none in our solar system, even out in the Oort cloud; it would've been seen by now by one of several different sky surveys.

我们知道太阳系里是没有的，甚至奥尔特云里也没有；它现在应该已经被几种不同的天空观测观测过了。

It is just too far. As it is, even with the Hubble telescope, we can't see even into the Oort cloud, so we don't actually know that it is there.

实在太遥远了。事实上，即便使用哈勃望远镜，我们也看不到奥尔特云，因此我们实际上不知道它在哪里。

The Oort cloud is thought to contain trillions of icy chunks, some of which, because of a collision or the pull of a passing star, from time to time fall inward.

人们认为奥尔特云包含数以万亿计的冰块，其中一些由于碰撞或擦肩而过的恒星的引力，不时向太阳系内坠落。

We won't get to the solar system's edge until we have passed through the Oort cloud, a vast celestial realm of drifting comets, and we won't reach the Oort cloud for another. I'm so sorry about this-ten thousand years.

要到达太阳系的边缘，我们非得穿过奥尔特云，那是个彗星飘游的茫茫天际。而我们--我为此感到很遗憾-还要再花1万年时间才能抵达奥尔特云。

But if you go even farther out, starting tens of billions of kilometers from the Sun, that disk of Kuiper Belt Objects merges into a vast spherical cloud of these ice balls called the Oort Cloud.

但如果你走得更远，从距离太阳几百亿公里外的地方观察，这片柯伊伯带就汇成了一个由冰球组成的巨大的球状云团，这被称为奥尔特云。