All types of galaxies have a core with a high star density. All galaxies with "arms" are called Spiral Galaxies, of which there are sub-types related to the shape of the arms.
A spiral galaxy
A spiral galaxy with a small, compact, bright nucleus that exhibits variable light intensity and radio-wave emission.
Our Milky Way has a supermassive black hole at its nucleus. It is an active radio source. It is probably not a Seyfert galaxy, which is a galaxy of a type characterized by a bright compact core that shows strong infrared emission, though.
The sun is not a planet that circles around a star. It makes part our galaxy, the milky way, which circles around itself. The circuit takes about 32,000 years.
a spiral galaxy like the milky way
The whole of the galaxy has a diameter of approx 100000 light-years, not just the nucleus! So it is not clear whether the question is about the galaxy or its nucleus.
the spiral galaxy is very bright because of its stars, that's why our galaxy is called the milky way because it looks milky and our galaxy(the milky way) is located in one of the arms of a spiral galaxy!
The Andromeda Galaxy has an apparent magnitude of +3.44
Yes. A Seyfert galaxy is a type of spiral galaxy, but with an active nucleus.
The stars in the spiral arms gradually rotate around the galactic nucleus
I wish I knew
it is called a spiral galaxy
Three of my Galaxy's properties: 1. Big 2. Bright 3. Cold