When that happens, you get that idealized soap bubble nebula.

如此来，就会得到理想肥皂泡星。

That's a very common shape for planetary nebulae.

这是行星状星很常见形状。

The orion nebula is a special kind of nebula called a stellar nursery.

猎户座星是种特殊星，叫做恒星摇篮。

In a lot of nebulae there's no sharp edge; they just kinda fade away.

在很多星中并没有尖锐边缘；它们只是会慢慢消失。

Those elements will spread out to become a nebula, a rich chemical cloud drifting through space.

这些物质最后会扩散开来，形新星，即大团富含化物质团飘逸在宇宙之中。

But sometimes nebulae do have sharp edges.

但有时星确实有锋利边缘。

Orion's sword is home to the great orion nebula, a cloud of dust, hydrogen, helium, and other gases.

猎户剑位置有猎户座星，是种由尘埃、氢气、氦气及其他气体组。

He saw clusters of stars, brightly colored nebulas, even entire galaxies!

他看到了无数星团，明亮星，甚至还看到了整个银河！

These can create lovely sheets, tendrils, and filaments in nebulae as well.

这些也可以在星中创造出可爱片状、卷须和丝状物。

However, this nebula started off more or less as a big shapeless blob.

但是开始这星或多或少更像个不形水滴。

It is a nebula: a star-forming region where new stars are being born.

个正在诞生新恒星恒星形区域。

Gas inside a nebula can be in turmoil, too.

星内气体也可能处于混乱状态。

So planetary nebulae really may owe their existence to planets!

所以行星状星存在可能真要归功于行星！

The Orion nebula is one of the wonders of the universe.

猎户座星是宇宙中奇迹之。

Among the other four images were two that showed huge clouds of gas and dust – called nebulas.

在其他四张照片中，有两张展示了巨大气体和尘埃——也就是星。

This object is what we call a planetary nebula.

这个物体就是我们所说行星状星。

Everything we find on the Earth today also originated in that nebula.

我们地球上切也都来源于那片星。

That usually happens when a gas cloud is expanding, like in a planetary nebula or supernova.

这通常发生在气体膨胀时，比如行星状星或超新星。

Stars, nebulae, stellar clusters of various sorts, the occasional supernova.

恒星、星、各种类型星团，偶尔还有超新星。

Not too far from the Orion Nebula in the sky is another dark nebula, superposed on a bright emission nebula.

天空中离猎户座星不远地方是另个暗星，它叠加在个明亮发射星上。