The Sun is located about 8,500 parsecs from the center, roughly in the center of the disk. On a clear night, we can see see the bright central regions of the galaxy as a bright streak across the sky. This is what we normally call the Milky Way . There are many theories on how the MW galaxy formed.
Some astronomers believe that the halo formed first.
In this theory, as gravity pulled the spherical halo material inward, the material formed a disk to conserve its angular momentum. These metals were spewed into the galactic medium through stellar winds and supernova explosions and became part of the disk. This means that the stars in the disk formed out of metal rich material. In this version, the disk and bulge formed first from a small cloud of material. The halo formed later as other small clouds were attracted to the galaxy by gravity and became bound to it.