All you need is a jetliner, a parabola and voila, you're weightless.

你需要的只是一架客机, 飞行个抛物线, 然后看看自己, 你已经失重了。

But because gravity makes the ball's trajectory a parabola, the air pushing against the ball changes directions as it flies.

但是因为重力使球的轨迹呈抛物线，所以当球飞行时，推动球的空气改变了方向。

An escape orbit is open — it doesn't come back — and is shaped like a parabola.

逃逸轨道是开放的——它不会回来——形状就像抛物线。

The orbit is now a hyperbola, which is similar to a parabola, but is even more open.

这种轨道是条双曲线，类似于抛物线，但更加开放。

There are 31 parabolas per flight.

每次飞行有 31 条抛物线。

Instead of a parabola that just goes like this.

而不是像这样的抛物线。

Or you could even think of it as a three-dimensional parabola.

或者您甚至可以将其视为三维抛物线。

He drew parallelogram and parabola up to par.

他画平行四边形和抛物线都是达到标准的。

Mathematically, the value of eccentricity varies between zero and one; with zero representing a circle and one transforming into another shape, called a parabola.

在数学上，偏心率的值在0和1之间变化，零代表一个圆，一个转换成另一种形状，称为抛物线。

The Greek mathematicians know the properties of the parabola and so could have directed the assembly of small mirror pieces into the parabolic shape.

希腊数学家知道抛物线的性质， 因此可以将小镜子碎片组装成抛物线形状。