Why does the Milky Way rotate?

We live in a galaxy that is called the Milky Way. It's called a barred spiral galaxy, which means that it has a spiral shape with a bar of stars across its middle. The galaxy is rather huge—at least 100,000 ...

Feb 11, 2015
3.4 / 5 (24) 30

What is a Wolf-Rayet star?

Wolf-Rayet stars represent a final burst of activity before a huge star begins to die. These stars, which are at least 20 times more massive than the Sun, "live fast and die hard", according to NASA.

Feb 06, 2015
5 / 5 (16) 0