Posted on 01/16/2012 9:18:55 PM PST by SunkenCiv
Explanation: Double, double toil and trouble; Fire burn, and cauldron bubble -- maybe Macbeth should have consulted the Witch Head Nebula. This suggestively shaped reflection nebula is associated with the bright star Rigel in the constellation Orion. More formally known as IC 2118, the Witch Head Nebula glows primarily by light reflected from bright star Rigel, located just below the lower edge of the above image. Fine dust in the nebula reflects the light. The blue color is caused not only by Rigel's blue color but because the dust grains reflect blue light more efficiently than red. The same physical process causes Earth's daytime sky to appear blue, although the scatterers in Earth's atmosphere are molecules of nitrogen and oxygen. The nebula lies about 1000 light-years away.
(Excerpt) Read more at 129.164.179.22 ...
[Credit & Copyright: Gimmi Ratto & Davide Bardini (Collecting Photons)]
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An honest, although possibly dumb question: Does that dustcloud and whatever other particles make up the nebula move, drift, change shape and/or appearance over time? By that I mean; this nebula was probably given its name a long time ago. Was there a time when it looked more like a witch’s head and is slowly drifting and changing appearance? Or is the drift and change over time morphing it even more into a shape suggestive of a witch’s head?
How long ago was it named, and could there come a time when it, and other nebulae with other names morph into other shapes which may or may not be suggestive of something else, or even suggestive of nothing at all?
Tilt your head to the right. Or basically, it looks like the side of someone’s face looking down to the right. Somewhat reminds me of the witch in the original Wizard of Oz movie.
Who knew the liberals have a nebula!?! :)
(Sorry, I just came off a debate high where Newt make Juan eat his race bait.)
Time and distance are inextricably linked on the astronomical scale. This nebula is very close, at 900 ly, but very large in the sky, at 3 X 1 degrees. If we figure that the various parts of the cloud can be moving at 1/1000 the speed of light, or 200 miles per second, a high estimate, I think, we get apparent movement of 1/900,000, or say 1/1,000,000 radians per year or 60/1,000,000 degrees per year. So in 1000 years, under this assumption, we would see change on the scale of 60/1000 or .06 degrees, compared to the 1 degree scale of the scene.
So, all in all, I would say that the appearance hasn’t changed much in the last few hundred years, but over a few thousand years it may. Just “back of the envelope” !
Hillary has her own nebula?
Yes, very slowly. You won't likely ever notice or detect movement in your life time, or the next two or so generations for that matter. In fact, unless something happened out of the ordinary within the nebula long ago, it should appear relatively the same from earth, for another 1000 years or so.
Ding dong the witches head...
More like, ‘witch’s face’
I also have a problem seeing a witch’s head, but then, as I have noted before, my eyesight isn’t what it used to be. Happens to most of us as we get older.
I can still appreciate most of the APODs though, so thanks, SunkerCiv.
I was goint to say that it looks like a Duckie or a horsie.........
If it were a little greener,
It would remind me of the “Angel Of Death” from DeMille’s “The Ten Commandments”!
Most items like this weren’t given ‘names’ until the advent of astronomical photography. It would have to been in the last 150+ years because no one could have seen in before that.
Or, if they did, it wouldn’t look like that.
I’ll get you My Pretty! And your little dog too!”
My sincere thanks to all the kind folks who answered my question regarding these nebulae.
Ver-r-r-ry Inter-r-r-r-resting!
You are viewing the right profile of her face, and her head is bowed toward the ground, while she screams at Toto. Poor little puppy....probably scared the poop out of him!
Here's one I shot not long ago of the eastern Veil Nebula NGC 6992
Veil Nebula is an old supernova remnant in the constellation Cygnus. It is the remains of cataclysmic explosion of star which exploded between 5,000 and 8,000 years ago. This nebula is about 1,860 light-years distance from our little home.
:’)
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