dark nebula


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Related to dark nebula: emission nebula

dark nebula

(dark cloud; absorption nebula) A cloud of interstellar gas and dust that is sufficiently dense to obscure partially or completely the light from stars and other objects lying behind it and sufficiently large and suitably located to produce a noticeable effect. These nebulae can be observed as dark extrusions in front of bright (emission or reflection) nebulae or as blank regions or regions with a greatly diminished number of stars in an otherwise bright area of sky. In external galaxies they are often observed against the bright spiral arms, where they appear as dark dust lanes. In our own Galaxy the dark clouds in Taurus are the nearest sites of star formation to the Sun. Although the absorption is caused by cosmic dust, the dark nebulae are composed predominantly of molecular hydrogen. Small dark nebulae, called Bok globules, can sometimes be seen in large numbers superimposed on bright nebulae. Although having no optical features dark nebulae can be studied through their radio and infrared emissions. The Coalsack, Horsehead nebula, and the Great Rift are dark nebulae.

dark nebula

[¦därk ‚neb·yə·lə]
(astronomy)
A cloud of solid particles which absorbs or scatters away radiation directed toward an observer and becomes apparent when silhouetted against a bright nebula or rich star field. Also known as absorption nebula.
References in periodicals archive ?
The brightest star in the sketch is eta Carinae, on the edge of a prominent dark nebula nicknamed the "Keyhole".
0) Dec NGC 6631 Open Cluster 18h27m2 -12[degrees]02' IC 1287 Diffuse Nebula 18 31 6 -10 47 NGC 6649 Open Cluster 18 33 5 -10 24 NGC 6664 Open Cluster 18 36 6 -07 49 NGC 6694 Open Cluster 18 45 2 -09 24 BARNARD 104 Dark Nebula 18 47 3 -04 34 NGC 6704 Open Cluster 18 50 9 -05 12 NGC 6705 Open Cluster 18 51 1 -06 16 NGC 6712 Globular Cluster 18 53 4 -08 42 IC 1295 Open Cluster 18 54 6 -08 50 Object Type Mag.
The team that made Dark Nebula are veterans in the games industry, and the game was designed by Anders Hejdenberg; the lead designer of many successful console and PC games including Battlefield 2: Modern Combat.
East of there the broad dark nebula was still easy to follow since, while there was a smattering of faint stars, there were far more outside of the boundaries plotted in MSA.
The dark nebula B64 is situated a few arc-minutes away towards the western field of view.
Gingka, the hero, and his group of loyal friends rally against a dangerous group called the Dark Nebula.
The whole area is covered in smoke-like gas and dust, with small parts of the dark nebula quite well defined against the very dense star-field (see combine sketch with NGC 6139).
His 16 minute guided exposure shows just how complex this whole area is, with the nebulosity extending out to mu Cephei (the Garnet Star) along with several intruding dark lanes, many of which have Barnard dark nebula designations.
The easiest way to find this dark nebula is to head east-northeast from Deneb about 7[degrees] about one binocular field) to the pretty open cluster M39, and then move the cluster off to the western edge of your field of view.
GOTHENBURG, Sweden -- Peter Bjorklund, the CEO of Outbreak Studios announced today that they have signed up with 1337 Game Design to develop the second episode of the game Dark Nebula for the iPhone and iPod Touch.
GOTHENBURG, Sweden -- A trailer for the game Dark Nebula was released today on Youtube, showing in-game footage of the title in action.