Most galaxies have a single nucleus, but the fascinating object in today’s APOD (Astronomy Picture of the Day) appears to have four. In fact, astronomers have concluded that the nucleus of the galaxy is not at all visible in this extraordinary photo of the Einstein Cross gravitational lens. The central cloverleaf is light emitted from a quasar directly behind the galaxy in our line of sight. The gravitational field of the foreground galaxy bends the light from the quasar into four distinct images.