NGC 6820/3, Emission Nebula/Open Cluster

This image was obtained with the wide-field view of the Mosaic camera on the KPNO 0.9m-meter telescope at Kitt Peak National Observatory. NGC 6820 is a diffuse emission nebula that surrounds the open cluster of stars NGC 6823 (at the center of the image). The intense light from the hot, massive stars in the cluster is blowing away the gas in the nebula, causing the distinctive "pillar" shapes on the left side of the image. The image was generated with observations in Hydrogen alpha (red), Oxygen [OIII] (green) and Sulfur [SII] (blue) filters. In this image, North is up, East is to the left.