Sharpless 308: The Dolphin-head Nebula

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SH2-308 The Dolphin-head Nebula

Image Credit & Copyright: Nik Szymanek

Explanation: This cosmic bubble was created by the fast winds of a massive, hot star. Sharpless 2-308 is its name. It lies approximately 5,000 light years away from the constellation of Canis Major (Canis Major). It covers slightly more sky than a Full Moon. This corresponds to an estimated diameter of 60 light years. Near the center of the Nebula is the brightest star, a Wolf Rayet star. Wolf-Rayet stars are 20 times more massive than the Sun. They are believed to be in a pre-supernova phase, which is a short-term phase of massive star development. The bubble-shaped Nebula is created by the Wolf-Rayet star's fast winds. They sweep up slower-moving material from an earlier phase. The age of the windblown nebula is approximately 70,000 years. The glow of ionized oxygen molecules mapped to a blue hue dominates the faint emission in the deep image. The Dolphin-head Nebula, also known as SH2-308, is a harmless area.