彗星的英文：
comet

That comet is invisible to the unaided eye.
那颗彗星只用肉眼是看不到的。

Recently they have discovered a comet.
最近他们发现了一颗彗星。

The nebulous,luminescent cloud containing the nucleus and constituting the major portion of the head of a comet.
彗发星云状的发光云体包括彗核、彗星头部的重要部分

An astronomer predicted the return of this comet [predicted that this comet would return].
一位天文学家预言这颗彗星将会重返。

a comet's sunward plunge;bathers facing sunward.
彗星的向阳运动;沐浴者向阳仰卧

A comet is at perihelion when it is closest (=very close) to the sun.
彗星最接近太阳时，它就是在近日点。

Today, astronomers espouse the theory that comets spawn the swarms.
如今，天文学家们支持彗星产生了流星团的说法。

We can see comets only when they come close to the Earth.
只有当彗星接近地球时，我们才能看得见它们。

Most stars probably have their quota of planets, meteorids, comets, and asteroids
多数恒星也许还拥有若干行星、流星、彗星和小行星。

If I had Binoculars, I could see that comet clearly.
如果我有望远镜，我就可以清楚地看见那颗彗星。

An astronomer predicted the return of this comet [predicted that this comet would return].
一位天文学家预言这颗彗星将会重返。

Today, astronomers espouse the theory that comets spawn the swarms.
如今，天文学家们支持彗星产生了流星团的说法。

The Comet, for example, was really only a fancy falcon
例如，慧星型车实际上不过是一部花哨的猎鹰车而已。

A comet is at perihelion when it is closest (=very close) to the sun.
彗星最接近太阳时，它就是在近日点。

Comets move around the sun like planets, but in long oval course.
彗星象行星一样绕太阳运转，然而其轨道呈狭长的椭圆形。