Coalsack Nebula
The Coalsack was a galactic nebula located in the southernmost part of the Milky Way Galaxy. The planet Cheron was located near the Coalsack. By the late 2260s, the region surrounding the Coalsack had not yet been charted by the . 

In 2268, when Spock speculated about the nature of the yet unidentified space amoeba encountered in Sector 39J, he remarked the amoeba was not like the Coalsack. ()

In 2269, the  was commandeered by Bele of the planet Cheron, who attempted to divert the Enterprise on course 403--7 from their position near Ariannus. Chekov remarked that the course would have taken them straight to the Coalsack. ()

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de:Kohlensack
es:Saco de Carbón
fr:Nébuleuse du Sac de Charbon
nl:Kolenzaknevel
Nebulae