comets

To discover just how much water comets contain, scientists deliberately crashed a space probe straight into it.

为了探明彗星中含多少水，科学家有意让一个太空探测器直接撞向它。

The abundance of olivine in comets is well established, but it's always been a bit of a mystery how it got there.

我们已经知道，大量的橄榄石存在于彗星之上，但是它是如何上去的却依然还是个谜。

So there might be more of them in the Kuiper Belt (where comets come from) as compared with the inner solar system near the sun.

所以或许相比于太阳系内部，它们在“柯伊伯带”（彗星形成之地）比较多。

Comets are just as much members of the sun's family as(are) the other planets.

彗星和其它的行星同样是日头亲族的成员。

Some researchers think comets might have originally brought some of the water and organic molecules to Earth that now make up life here.

一些研究者认为，可能是彗星最早把水和有机分子带到了地球，发展出了现在地球上的生命。

Composed primarily of ices, most comets circle the dark fringes of the solar system, barely within the sun's gravitational grasp.

大部分彗星主要由冰块构成，环绕太阳系黑暗的边缘运行，几乎超出了太阳的引力范围。

The constant in this equation is the same for any objects orbiting around the Sun, including planets, comets and artificial satellites.

公式中常数的数值，对所有行星以至一切环绕太阳运动的人造或天然物体皆适用。

This artist's concept illustrates how silicate crystals like those found in comets can be created by an outburst from a growing star.

本艺术概念图显示一颗早期恒星如何通过初期的爆发产生硅酸盐晶体（彗星中就有发现）的。

Any school kid can tell you that comets are made of ice. That frozen water burning off is what gives comets their characteristic tails.

你随便问一个小孩他都能告诉你彗星是由冰组成的，而且冰的燃烧“给”了彗星一条长尾巴。

The comets' offspring, the meteor swarms, travel in regular orbits, similar to the earth's orbit around the sun.

彗星的后裔，即流星团，沿正常的轨道运行，与地球绕太阳运行的轨道相似。

Comets are just as much members of the sun.

彗星和其它的行星同样是太阳家族的成员。

Nemesis is not the only possible explanation for regular collisions between Earth and comets.

地球和彗星之间会产生规律的大碰撞，不一定真的是由涅墨西斯造成的。

It was compressed enough to become a protostar but enough material was left over to form planets, moons, asteroids and comets.

压力足够使之形成一颗恒星，剩下的物质形成了行星，卫星，小行星和彗星。

Our work brings to light another component in the formation that we had not anticipated - comets.

我们的工作现在揭示了我们原先没有料想的在地球和月球形成时的另外一个元素------彗星。

Some of that uncertainty comes from asteroids' sometimes forgotten cousins, comets.

上文提到的不确定性，有一部分来自于小行星那偶尔被遗忘的表兄——彗星。

Now, far beyond that as well, between the stars, with the blackness of space, the shining planets, comets, suns, and stars. . .

现在，也像是远离地球，在星际间穿梭，在漆黑的太空中，星球、彗星、太阳和星星闪烁发光…

Asteroids and comets smashing into the early Earth have long been thought to be a promising source.

一直以来人们认为海水可能来自早期坠入地球的小行星和彗星。

In Earth's formative years, it was hit by thousands of comets like this.

在地球的最初岁月中，它曾被成千上万个这样的彗星撞击。

It includes the sun, eight planets and their satellites, asteroids, comets, meteoroids and interplanetary matter.

它包括太阳、八大行星及其卫星、小行星、彗星、流星体以及行星际物质。

Some comets, called sun-grazers, smash right into the sun or get so close that they break up and evaporate.

一些被称为“掠日彗星”的彗星，会被撕碎并坠入太阳，或者由于过于靠近太阳而解体蒸发。