the galaxyΓÇÖs center, known as the bulge. Because we see the disk edge-on, it is difficult to recognize the spiral arms. The black streaks are caused by interstellar material obscuring starlight. The galaxyΓÇÖs center is dominated by a hazy ball of stars. The stars in the disk and the bulge are radically different in composition, color, and age from those in the center, although the differences are not easy to see in this photograph.
