A small, dense cloud of dust and gas, usually rounded in shape, that appears dark through being seen in silhouette against a bright nebula or starfield. Globules are the smallest of the dark nebulae, and are usually less than 1 l.y. across; the smallest are only a few light days across and contain less than 1 solar mass. They are often called Bok globules, after B. J. Bok, who drew attention to them and suggested that they may be protostars. See also cometary globule.

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