M57, The Ring Nebula in Lyra


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Description: The ring nebula is one of the brightest planetary nebula in the sky.  It was formed when the central star, here visible as blue, ejected its outer shell of material.  20 hours of H alpha data was blended with the image to show a secondary and tertiary outer shell.  The latter is almost perfectly spherical.  To the upper right is IC1296, a small irregular galaxy.
Exposure Data: 5/16-23/2005.  L: 27x5m, Ha: 59 x 20m. -25C, 0.55 arc-sec./pixel.
Processing: Multi-night automatic acquisition and dithering via CCDAutoPilot2 and CCDSoft, reduced and aligned, in Mira, L: 50 iterations RL decon, L+Ha combine, curves, levels, Gredient Xterminator  and other processing in Photoshop.
Optical System: 14.5 Ritchey-Chretien @ F/9 w/FFC, IMG6303E/CFW-7 CCD camera, AstroDon filters, Paramount ME, dithered 3 pixels, off-axis guided .
Comments: The background is raised to show the very faint tertiary shell.  Total imaging time to date is 22 hours.