It varies. I used to work for a Physics and Astronomy department, yes, some of them are interested in telescopes, of various sorts, and indeed that's the department running the scheme where lay people can look at interesting stuff in the sky using a mid-size optical telescope. But, there's a lot of deep physics, that's why it's a physics department. At scale some of the physical properties from everyday life we usually don't notice stop being negligible and because we're small that scale is called astronomy.

For example if you have a whole bunch of Hydrogen the gravity its exerting on itself is negligible... Unless it's a lot of Hydrogen because eventually instead of being negligible the gravity adds up to where the Hydrogen atoms undergo nuclear fusion and that's how you get stars.

Similarly, Oceanography does have boats and a large building next to the sea, but although some of them are capable sailors, a lot of what they're interested in is theoretical and doesn't require you to even be able to smell the sea, let alone go out on it.

Perfect - your background means I can speak a language you will understand.

The reason we know anything about the composition of stars, the distance to galaxies, their relative speed etc. is because we use a telescope and study spectral lines.

Your comparison of oceanography and boats is a poor analogy. The a analog to telescopes would be sonar (and maybe seismographs?). The analog to boats would be spaceships/rockets. This makes my point.