M57, NGC 6720, Ring Nebula

The existence of considerable material outside the normal `ring' shown in pictures of the Ring Nebula has been well known for some time, but most images of the nebula continue to emphasize the structure as `usual suspect'. In this deep CCD image made with the Kitt Peak 2.1-meter telescope, I have created a fake `double exposure', to reveal the interesting outer structure, while overlaying the now saturated inner regions with the more usual sort of picture showing the inner detail. The colors and their distribution in the outer nebula indicate the physical state of the material as it expands away from the central star. This can be compared with our older picture from the Mayall 4-meter, taken in 1973. This picture was obtained during the year 2000 Research Experiences for Undergraduates program, funded by the National Science Foundation. The background galaxy IC1296 (top right) never shows up in the usual pictures.