Coalsack(redirected from Coalsack Nebula)
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Coalsack:see Milky WayMilky Way,
the galaxy of which the sun and solar system are a part, seen as a broad band of light arching across the night sky from horizon to horizon; if not blocked by the horizon, it would be seen as a circle around the entire sky.
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Coalsack(kohl -sak) (Southern Coalsack) A prominent dark nebula about 170 parsecs away in the southern constellation Crux. It has an angular diameter of 6° and can be seen with the naked eye as a completely black shape silhouetted against the background of the Milky Way.
An area in one of the brighter regions of the Southern Milky Way which to the naked eye appears entirely devoid of stars and hence dark with respect to the surrounding Milky Way region.