What is the X in X-mas?
|barred spiral galaxy |
A spiral galaxy with a barlike bulge in the center, extending between the core and the spiral arms. About a third of spiral galaxies have this straight bar of stars, gas, and dust extending out from the nucleus. As with other spiral galaxies, barred spiral galaxies rotate, and new stars form from the dust and gas in their arms. Astronomers believe that some elliptical galaxies containing hints of a bar and spiral might once have been barred spiral galaxies.