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This image was obtained with the wide-field view of the Mosaic camera on the Mayall 4-meter telescope at Kitt Peak National Observatory. Abell 74 is an ancient planetary nebula. Because of its age it is a very faint target. Ancient planetary nebulae are often distorted in shape due to interactions with the interstellar medium. Interestingly, Abell 74 is remarkably symmetric despite its age. The image was generated with observations in the Hydrogen alpha (red) and Oxygen [OIII] (blue) filters. In this image, North is left, East is down.
Image Credit: T.A. Rector (University of Alaska Anchorage) and H. Schweiker (WIYN and NOAO/AURA/NSF)
Image enhancement: Jean-Baptiste Faure