emission lines
-

What are Seyfert Galaxies?
Meet NGC 1566, an intermediate spiral galaxy in the constellation Fornax. To the human eye, this galaxy looks almost like any other spiral: It has a central nucleus and spiral arms, and it’s full of gas and dust. As an…
-

Interstellar Spectra
I often refer to what we call the interstellar medium as the galaxy’s “backstage,” and I do that for a reason: for the most part, we can’t see it. The backstage of any theater isn’t part of the show. You, as…
-

The Atomic Spectrum
Astronomers know that if white light passes through a prism and is bent, it’s separated out into its component colors — the colors of the rainbow. Astronomers also know that when light interacts with atoms, the building blocks of the…
