Posted on 05/24/2012 9:39:09 PM PDT by SunkenCiv
Explanation: Cosmic dust clouds dim the light of background stars. But they also reflect the light of stars nearby. Since bright stars tend to radiate strongly in the blue portion of the visible spectrum, and the interstellar dust scatters blue light more strongly than red, the dusty reflection nebulae tend to be blue. Lovely examples are the wispy blue reflection nebulae near bright, hot stars Pi and Delta Scorpii (upper left and lower right) in this telescopic skyscape from the head of the constellation Scorpius. Of course, the contrasting red emission nebulae are also caused by the hot stars' energetic radiation. Ultraviolet photons ionize hydrogen atoms in the interstellar clouds producing the characteristic red hydrogen alpha emission line as the electrons recombine. About 600 light-years away, the nebulae are found in the second version of the Sharpless Catalog as Sh2-1 (left, with reflection nebulae VdB 99) and Sh2-7. At that distance, this field of view is about 40 light-years across.
(Excerpt) Read more at 129.164.179.22 ...
[Credit & Copyright: John Davis]
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As Always...Awesome!
Beautiful. I’m always awed.
It started out Tars, then kept getting Tarsier.
I recall, in my amateur astronomy days, a cluster in Scorpio that I called ‘the Christmas Cluster’. It was an open group of red and green stars.
Never determined its catalog number or if it had one.
May have just been background stars but a beautiful view.
And they’re nocturnal, tarsiest at night, just like Scorpius in Red and Blue!
That’s “tarsiest,” not “tastiest.”
Endangered species, Mr. Civilizations!!
“Cosmic dust clouds” - you know, they wouldn’t have these problems if they would just pave their roads.
;’)
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