Astronomy Picture of the Day . ... A fantastic jumble of young blue star clusters, gigantic glowing gas clouds, and imposing dark dust lanes surrounds the central region of the active galaxy Centaurus A. This mosaic of Hubble Space Telescope images taken in blue, green, and red light has been processed to present a natural color picture of this cosmic maelstrom. ... Blue light from the star Rho Ophiuchi and nearby stars reflects more efficiently off this portion of the nebula than red light. ...