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Figure 14-30 RIVUXG Quasars and Their Host Galaxies (a) In this 1994 image from the Hubble Space Telescope (HST), the glare of quasar 3C 273 hides its host galaxy. (b) This 2002 image that reveals the host galaxy was made using an upgraded camera aboard HST. (c) Quasar PG 0052 + 251 is located at the center of an apparently normal spiral galaxy. Other quasars are found at the centers of ordinary looking elliptical galaxies. (d) The galaxy that hosts quasar PG 1012 + 008 is in the process of merging with a second luminous galaxy. The wispy material surrounding the quasar may have been pulled out of the galaxies by tidal forces (see Figure 14-24). The two merging galaxies are just 31,000 ly apart. Another small galaxy to the left of the quasar may also be merging with the others.