As the planet orbits the star, it makes a big circle (or ellipse) .

当行星围绕恒星运行时，它会成一个大圆(或椭圆)。

Not only that, the Moon orbits the Earth on an ellipse.

不仅如此，月球绕地球公转轨道是椭圆。

It has two points, called foci, which act as a combined center for an ellipse.

它有两个点，称为焦点，作为一个椭圆联合中心。

This ellipse has an important property called eccentricity.

椭圆有一个重要性质，叫做离心率。

For one thing, it's not a perfect circle, it's quite an elongated ellipse.

至少不是一个标准圆，而像是一个拉长椭圆。

The equation is a way to compare these axes to describe how squashed the ellipse is.

这个方程是比较这些轴来描述椭圆扁平度一种方式。

An ellipse with zero eccentricity would just be a regular old circle.

偏心率为零椭圆就是一个普通圆。

And b is the semi-minor axis, or half the distance along the short axis of the ellipse.

b 是半短轴，或者说椭圆短轴距离一半。

Remember too that the Moon's orbit around the Earth is an ellipse.

同样要记住是，月亮绕地球公转轨道是个椭圆。

As Kepler showed, the earth's orbit is an ellipse, with the sun at one of the two focal points.

就像开普勒曾指出，地球轨道是个椭圆，相对以太阳为中心绕起来话有两个焦点。

And as if they were cuboidal cells that got stretched tall, their nuclei also are stretched into an ellipse.

由于它们是立方体细胞，被拉伸得很高，它们细胞核也被拉伸成椭圆。

As eccentricity increases, the ellipse gets flatter and flatter until it just looks like a line.

随着偏心率增加，椭圆会变得越来越平，直到它看起来像一条线。

An ellipse is an asymmetrically shaped closed oval.

任何椭圆都是对称封闭椭圆。

Now, Newton predicted that the orbit of Mercury was an oval, or as scientists like to say " an ellipse."

牛顿预测水星轨道是椭圆，或者用学家惯用词，“椭圆”。

To those wondering what an extreme ellipse could be, there's a great example to look at Halley's Comet.

对于那些想知道什么是极端椭圆人来说，有一个很好例子，那就是哈雷彗星。

Instead, they generally have a stretched version of a circle, which is technically called an ellipse.

相反，它们通常有一个圆拉伸公转，也就是椭圆。

Well, an ellipse is a shape that resembles a kind of squashed circle.

椭圆是一种类似于被压扁圆状。

Weighing all the possibilities, the computer spits out the potential area of impact in the form of a landing ellipse.

权衡过所有可能性，计算出一个可能接触区域，一个椭圆着陆区。

Simply put, eccentricity tells how much the ellipse deviates from a perfect circle.

简单地说，离心率表示椭圆与正圆偏离程度。

Its foci are two points within the ellipse that describe its shape.

它焦点是椭圆内描述其状两个点。