nebula GREGMAT

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的花朵，一撮星是无数天体的蚁聚。

You can see nebulae in the clear summer sky.

在晴朗的夏夜可以看到天上的星。

Extragalactic nebula is invisible to the naked eye.

我们肉眼是看不到河外星系的。

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.

当我们的星在自身重力作下崩溃和更加快速地旋转时，星中心形成了密集的物质块。这叫做原恒星。