nebulae

Extragalactic nebula is invisible to the naked eye.

我们用肉眼是看不到河外星。

You can see nebulae in the clear summer sky.

晴朗夏夜可以看到天上星云。

A bit of mould is a pleiad of flowers;a nebula is an ant-hill of stars.

一粒霉菌是一簇美不胜收花朵，一撮星云是无数天体蚁聚。

The tiny but intriguing yellowish arc visible near the blue nebulae marks young variable star R Coronae Australis.

蓝色星云附近，微但迷人微黄色弧状可见物标出了年轻可见恒星南冕座R星位置。

As our nebula began to collapse under its own gravity and spin faster, a dense clump of matter formed in the center. It's called a protostar.

当我们星云自身重力作用下崩溃和更加快转时，星云中心形成了密集物质块。这叫做原恒星。