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Related to Coalsack: cul de sac


1. A dark nebula, one of the nearest to Earth, that appears in the southern Milky Way.
2. A similar dark nebula in the Northern Hemisphere near the constellation Cygnus.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


a sack in which coal is carried
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014



1. a dark nebula in the Southern Cross.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
In a position in which each word must be balanced against the fine weight of the gold leaf adorning the Foreign Office's Locarno Room, Johnson is a coalsack on the featherweight scales.
How often have we read that the complex of Milky Way dust clouds composing the Great Rift broadens into the Northern Coalsack, then ends at Deneb?
To many Aboriginal language groups across Australia, the Coalsack (which is a dark nebula next to the Southern Cross) represents the head of the Emu in the Sky, an Aboriginal 'constellation' that stretches from the head to the body and legs, through the dark lanes in the Milky Way, to the constellation Scorpius (Norris and Norris 2009:5-6).
Dark regions within the band, such as the Great Rift and the Coalsack, correspond to areas where light from distant stars is blocked by interstellar dust.
The Magellanic clouds in the south, the Southern Cross with the Coalsack clearly distinguishable and the magnificent starfields of the Crux region; even Omega Centauri and 47 Tucanae were all easily visible without the intervention of a pair of binoculars.
In contrast, the Coalsack, which sprawls between Alpha and Beta, is a region apparently devoid of stars.
Coalsack, winner of the Carlos Pellegrini in 1998, stayed on for third, another four lengths back.
"The Light and the Dark: A Reassessment of the Discovery of the Coalsack Nebula, the Magellanic Clouds and the Southern Cross." Annals of Science 47:529-560.
They are known variously as the Snake, the Horsehead, the Coalsack. Darkness is not an absence but a rich and dense presence, a kind of cosmic chocolate, a forest of stellar events whose existence is known only by its invisibility.
This panorama, captured near Christchurch, New Zealand, shows Alpha and Beta Centauri (the bright pair on the Milky Way's band at lower left), the Southern Cross and Coalsack (left of center), the Large and Small Magellanic Clouds (below center), Canopus (right of center), and Sirius (upper right).