Approaching and entering a galaxy

I'm fascinated by this scenario that is possible in theory only.

Imagine that you're approaching a sprial galaxy, tilted on its edge a bit, in a space ship traveling close to the speed of light or whatever. What initially appeared as a tiny smudge, obviously, would get larger and larger to your view until at some point it occupied the entire sky. Would it at that point appear as a feintly visible sprial-shaped smudge, or would it be sparking and brilliant at some point? Surely this is one of the most remarkable views to contemplate. I wish an artist would attempt a rendition.

As you could closer to the galaxy, it would resolve into a more or less typical night sky, I assume.

It would no doubt be a spectacular view, and I think you basically have the ideas right. It would get bigger and bigger and eventually you'd start to be able to see individual stars on the side closest to you, but there would be a big blurry thing occupying half the sky. And as you got inside it the stars would pass overhead and little by little you'd start seeing something like our night sky. I guess it would be most impressive when you were close enough that it dominated the sky but far enough that you could still see it in one visual frame.

If you're traveling close the speed of light you would have relativistic visual effects to contend with. See this page:

http://www.phys.ncku.edu.tw/mirrors/physicsfaq/Relativity/SR/Spaceship/spaceship.html

The faster you go, the more distorted it would be. The reality is, we can get a better view with simulated views, or computer enhanced images. Our unassisted eyes aren't the best way to see the universe.

A large spiral like the Milky Way would appear brighter overall than it does in our sky, but mainly because of the core. The arms would have brightness comparable to what we see from Earth, with probably many slightly brighter patches of star forming regions like the Orion nebula.

Looking through a telescope at other galaxies is similar to what you are asking about. The Sombrero Galaxy is pretty impressive.

It is also worth noting that IF you were approaching at near the speed of light, the photons coming to you would be blue shifted significantly, and what you would see would be something in the far infrared, microwave, or radio range shifted into the visual range. The photons getting to your eyes would not necessarily show you stars... And the visible light from stars would be blue shifted to a range that would kill you if you didn't filter them out somehow.

Galaxies as we see result from long photographic exposures. A real time observation wouldn´t be that glorious. The Magellanic clouds are very close, but all you see are faint smudges.