The spherical cloud of stars that lies at the center of spiral galaxies.
The is the central, spherical part of a spiral galaxy. It is surrounded by a disk-shaped mass of stars with spiral arms.
Size of nuclear bulge (Sa=large; Sc=v. small)
Openness of spiral pattern (Sa=tightly wound; Sc=v. open) ...
nuclear force That force exerted by subatomic particles that is responsible for form, shape, and motion in the subatomic world of the nucleus. nucleic acid Substance of the DNA molecule.
@Larian LeQuella: You can see a small portion of the nuclear bulge of our Galaxy, just outside the disk of galactic dust, below the direction to the galactic center in the constellation Sagittarius.
Surrounding the central nucleus of a spiral galaxy is a large , which is nearly spherical in most cases and may have a diameter of up to half that of the disk.
In Hubble's classification, a spiral with a large nuclear bulge and closely coiled arms. [H76]
Hot stars of spectral types O, B, A, and early F. [H76]
They are often chaotic in appearance, with neither a nor any trace of spiral arm structure. Collectively they are thought to make up about a quarter of all galaxies.
As previously discussed the halo stars and globular clusters, and the nuclear bulge probably formed first, followed by the disk of our galaxy. Galaxies in general must have formed out of great clouds of gas collapsing due to their own self-gravity.
There is a 9th mag star on the western tip of this galaxy. The bright middle shows an obvious with a very suddenly brighter nucleus. I believe this bright central section is what led Herschel to call this object "round".
Population II: Stars poor in atoms heavier than helium; relatively old stars found in the halo, globular clusters, or the nuclear bulge.
See also: Galaxy, Bulge, Orbit, Astro, Star