Bok globules

(bok) Small dark cool (10 K) clouds of gas and dust seen as near-circular objects against a background of stars or of an H II region; they are named after the American astronomer Bart J. Bok. They are believed to represent a late phase in the contraction of some dense cores when the material has become sufficiently dense to be opaque at optical wavelengths. The main sites for star formation are now known to be giant molecular clouds, but Bok globules give rise to some of the Galaxy's lower-mass stars. Most globules have diameters between 0.2 and 0.6 parsecs, and absorb between one and five magnitudes of light. Their mass varies from 20 to 200 solar masses. IRAS and other infrared telescopes have located protostars within some Bok globules; bipolar outflows from these produce Herbig–Haro objects seen at the globule's edge.

单词	bok globules
释义	DictionarySeeBok globule Bok globules Bok globules (bok) Small dark cool (10 K) clouds of gas and dust seen as near-circular objects against a background of stars or of an H II region; they are named after the American astronomer Bart J. Bok. They are believed to represent a late phase in the contraction of some dense cores when the material has become sufficiently dense to be opaque at optical wavelengths. The main sites for star formation are now known to be giant molecular clouds, but Bok globules give rise to some of the Galaxy's lower-mass stars. Most globules have diameters between 0.2 and 0.6 parsecs, and absorb between one and five magnitudes of light. Their mass varies from 20 to 200 solar masses. IRAS and other infrared telescopes have located protostars within some Bok globules; bipolar outflows from these produce Herbig–Haro objects seen at the globule's edge.
随便看	poises themselves for poises yourself for poise themselves for poiseuille poiseuille equation poiseuille flow poiseuille, jean leonard marie poiseuille, jean louis marie poiseuille law poiseuille's law poiseuille space poiseuille's space poiseuille viscosity coefficient poise upgrade mission payload system poise yourself for poisha poisindex poising poising for poising herself for poising himself for poising myself for poising oneself for poising ourselves for poising over