Shadows Helped Form the "Pillars of Creation"
Written by Nancy Atkinson
How were the famous "Pillars of Creation" formed? Perhaps only the shadow knows! New research suggests that shadows hold the key to how giant star-forming structures like the “Pillars" in the Eagle Nebula take shape.
The pillars are dense columns within giant clouds of dust and gas where massive stars form. Several theories have been proposed to explain why the pillars develop around the edge of ionized gas bubbles surrounding young, very hot stars. Using computer models, a group of astronomers from the Dublin Institute of Advanced Studies has found that partially-shadowed clumps of gas tend to creep towards darker areas, causing pile-ups behind dense knots of gas and dust that screen the intense ultraviolet light emitted by the stars.
Jonathan Mackey, who is presented the results at the European Week of Astronomy and Space Science in the UK said, “We created a simulation with a random distribution of lots of dense clouds with different sizes and shapes. We found that in certain cases a number of clouds can merge together in the shadows to form structures that look very like observed pillars. They are sufficiently dense to match the observations, can form in about 150,000 years and can survive for about 100,000 years. Although this is a preliminary study, we believe our results are quite robust and will be confirmed by more detailed modeling.”
The team, led by Dr. Andrew Lim, found that the configuration of clumps of gas had to be favorable for the pillars to form. Some age estimates put the Eagle Nebula pillars at no more than 100,000 years old, and models show that the shadow from a single clump would not attain the density to form a pillar in that relatively short timescale.
“Many of our models do not produce pillars that are as long and narrow as those in the Eagle Nebula, at least not at the observed gas density. It needs the right configuration of dense clumps of gas to form a long pillar. Unless the shadowed region is already very dense to begin with, it just takes too long to collect and organize the gas into a pillar,” said Lim.
The group plans to add increasing levels of realism to the model over the next couple of years, bringing in more accurate representations of the complex chemistry of interstellar gas, the effects of radiation from diffuse sources. Adding in the effects of gravity will also be important as the pillars contain dense gas condensations which are in the process of collapsing under their own weight to form the next generation of stars.
Mackey said, "Gravity is relatively unimportant when the pillars are forming, but there comes a point when they get very dense and it cannot be ignored any longer. We plan to include gravitation in future work so that we can study the next generation of stars which are forming in the pillars."
Source: RAS
Filed under: Astronomy
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April 22nd, 2009 at 7:46 pm
Almost seems like the pillars of shadows are eating the stars. Perhaps it is a universal parasite? It would make sense because here on our planet we have parasites and since the universe is just a larger version of the same picture we should assume that something of this nature could be possible. I believe the Big Bang Theory is possible but I have come to adopt a Universal Recycling Theory. Basically I believe that every thing in the universe churns around on and back into one center point, similar to how the Earth's crust comes to the surface than churns back in. This is what makes it appear that the undiverse is expanding when in all reality it is but it can only expand back to the center point. Infinity is Zero, Zero is Infinity. I know this is kind of a scattered thought but if you just think about it then you will understand. Everything works the same just on a different scale.
Perhaps intelligent life is being created to help the universe's white blood cells(stars) combat this disease similar to how cold medicines complement the immune system for a speedier recovery. It boggles my mind to think about it but it could be a theory worth looking into. It would be sad if our universe is being eaten or destroyed by some sort of disgusting astronomical parasite or virus. If so then it would make you wonder what the point in fighting each other is when we apparently have bigger problems to deal with. Think about it.
April 22nd, 2009 at 8:34 pm
So here we have mainstream theory ignoring gravity in favour of electromagnetic influences… But everybody keeps saying that mainstream theory fails because it ignores electromagnetic influences in favour of gravity.
It's a puzzle…
:3
April 22nd, 2009 at 8:37 pm
JustinnitsuL: You've done it. I am officially speechless. There is nothing I can add that could possibly add or contribute to what you just said there. Bravo, sir, and may God have mercy on your soul.
April 22nd, 2009 at 9:40 pm
The electromagnetic process of star formation goes something like this:
A Birkeland current is present, then a z-pinch constricts a segment of the Birkeland current, this in turn causes instabilities and Marklund convection that gathers in matter and a plasmoid forms.
How's that for star birth in less than 60 seconds, or is it 100,000 years, I forget:-)
April 23rd, 2009 at 12:14 am
Tammy, Yukka, are you there?
I'd like to see a Stereo Pair version of the second picture…..
April 23rd, 2009 at 12:29 am
Annaconda – if that was directed at me, you completely missed the point of my post (And the article as well).
April 23rd, 2009 at 1:13 am
"A Birkeland current is present, then a z-pinch constricts a segment of the Birkeland current, this in turn causes instabilities and Marklund convection that gathers in matter and a plasmoid forms.
How’s that for star birth in less than 60 seconds, or is it 100,000 years, I forget:-)"
It'd be kick-arse if there was any evidence to corroborate the non-existent quantitative predictions that it doesn't make!
BAM – THAT JUST HAPPENED!
April 23rd, 2009 at 1:14 am
P.S – Nancy – those are my two favourite Hubble images of all time. You rule for putting them up in the same post.
April 23rd, 2009 at 5:42 am
JustinnitsuL: You do realize that Star Trek isn't real, right?
April 23rd, 2009 at 8:04 pm
Uhh…I don't think they're eating the stars, dude xD
April 23rd, 2009 at 11:00 pm
This is nonsense until the effects of gravity are added into the simulation.
April 24th, 2009 at 5:54 am
I'm with Feenixx. I would like to see a 3D picture too. I love those! I haven't seen one in a while (am I missing them or have they quit being "published"?). Beautiful photos!!
April 24th, 2009 at 1:21 pm
Those two are the greatest photos of all time and could never be equaled. What they've done for the study of the Cosmos is beyond words.
Next time you think you are having a bad day, spend a minute looking at the Eagle Nebula………. The only thing better is a puppy licking your face!