by APOD Robot » Sun Dec 14, 2014 5:05 am
Molecular Cloud Barnard 68
Explanation: Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark
molecular cloud. Here, a high concentration of
dust and
molecular gas absorb practically all the visible light emitted from background stars. The eerily dark surroundings help make the interiors of
molecular clouds some of the coldest and most
isolated places in the universe. One of the most notable of these
dark absorption nebulae is a cloud toward the constellation
Ophiuchus known as
Barnard 68,
pictured above. That no stars are visible in the center indicates that
Barnard 68 is relatively nearby, with measurements placing it about 500 light-years away and half a
light-year across. It is not known exactly how
molecular clouds like
Barnard 68 form, but it is known that these clouds are themselves
likely places for
new stars to form. In fact,
Barnard 68 itself has
been found likely to collapse and form a new star system. It is possible to
look right through the cloud in
infrared light.
[/b]
[url=http://apod.nasa.gov/apod/ap141214.html][img]http://apod.nasa.gov/apod/calendar/S_141214.jpg[/img] [size=150]Molecular Cloud Barnard 68[/size][/url]
[b] Explanation: [/b] Where did all the stars go? What used to be considered a hole in the sky is now known to astronomers as a dark [url=http://en.wikipedia.org/wiki/Molecular_cloud]molecular cloud[/url]. Here, a high concentration of [url=http://apod.nasa.gov/apod/ap030706.html]dust[/url] and [url=http://apod.nasa.gov/apod/ap970430.html]molecular gas[/url] absorb practically all the visible light emitted from background stars. The eerily dark surroundings help make the interiors of [url=http://www.youtube.com/watch?v=YbdwTwB8jtc]molecular clouds[/url] some of the coldest and most [url=http://lh5.ggpht.com/__zoKJ77EvEc/TUunWxcWVlI/AAAAAAAAKyc/JW7UNzSdeS4/house-ellidaey5%5B2%5D.jpg]isolated place[/url]s in the universe. One of the most notable of these [url=http://apod.nasa.gov/apod/dark_nebulae.html]dark absorption nebulae[/url] is a cloud toward the constellation [url=http://en.wikipedia.org/wiki/Ophiuchus]Ophiuchus[/url] known as [url=http://en.wikipedia.org/wiki/Barnard_68]Barnard 68[/url], [url=http://www.eso.org/gallery/v/ESOPIA/Stars/phot-02a-01.tif.html]pictured above[/url]. That no stars are visible in the center indicates that [url=http://en.wikipedia.org/wiki/Edward_Emerson_Barnard]Barnard[/url] 68 is relatively nearby, with measurements placing it about 500 light-years away and half a [url=http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html]light-year[/url] across. It is not known exactly how [url=http://archive.ncsa.uiuc.edu/Cyberia/Bima/GMC.html]molecular clouds[/url] like [url=http://curious.astro.cornell.edu/question.php?number=597]Barnard 68[/url] form, but it is known that these clouds are themselves [url=http://apod.nasa.gov/apod/ap070218.html]likely places[/url] for [url=http://en.wikipedia.org/wiki/Star_formation]new stars to form[/url]. In fact, [url=http://adsabs.harvard.edu/abs/2009ApJ...695.1308B]Barnard 68[/url] itself has [url=http://www.universetoday.com/2009/06/09/astronomers-predict-birth-of-a-new-star/]been found[/url] likely to collapse and form a new star system. It is possible to [url=http://www.eso.org/public/news/eso9934/]look right through[/url] the cloud in [url=http://coolcosmos.ipac.caltech.edu/cosmic_classroom/ir_tutorial/discovery.html]infrared[/url] light.
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