A category for which these structures are “broken” was added to a morphological system by Gérard de Vaucouleurs (“ZHAY-rah duh VOH-koo-lur”). These structures rotate with a quantity denoted capital omega-sub-p called pattern speed. Though it was later applied to planetary rings, the “winding problem” of the persistence of these structures (20[1])motivated the development of Lin–Shu density wave theory. These structures are the defining features of members of both right branches of the (*) Hubble tuning fork. (0[1])Orion lends its name to (10[1])one of these structures that contains the Earth. (10[1])These structures are directed outward from a central bulge and may be connected by a “bar.” For 10 points, name these spoke-like structures that distinguish spiral galaxies from elliptical galaxies. (10[2])■END■