APOD: Caught in the Afterglow (2011 Nov 24)

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Expand view Topic review: APOD: Caught in the Afterglow (2011 Nov 24)

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Devil Particle » Mon Nov 28, 2011 6:09 pm

Chris Peterson wrote:
If anything, this data adds support to the Big Bang cosmology, since it predicts a more active early Universe.

In science, "skepticism" means being open to new theories when they present themselves; it does not mean "doubt" in the usual sense. Most cosmologists accept the Big Bang as describing reality because it is so strongly supported by multiple lines of evidence. That doesn't mean that they would stick to it dogmatically if a better theory comes along... but so far, nothing else comes close to explaining what we observe."
Chris, concerning skepticism, I understand your point of view so I'll try to keep this focused in current scientific thinking as best I understand it.

The reason I asked the question is I thought that galaxies in the early universe were supposed to have less heavy elements than older galaxies like our own Milky Way. This APOD seems to suggest that the finding is different. But you seem to be suggesting that this result is not surprising. Am I to understand that older galaxies and younger galaxies (as seen from Earth) are expected to have similar amounts of heavier elements?

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Chris Peterson » Sun Nov 27, 2011 12:55 am

Devil Particle wrote:Does this put even a slight dent in Big Bang Theory? I always wonder how much we don't understand. Given that we are born and die and many scientists come from backgrounds involving creation theories isn't there any skepticism within the scientific community that maybe the interpretation of the empirical data is skewed by our natural biases? I mean doesn't this data in some ways suggest that the universe is older than current scientific opinion thinks it is?
If anything, this data adds support to the Big Bang cosmology, since it predicts a more active early Universe.

In science, "skepticism" means being open to new theories when they present themselves; it does not mean "doubt" in the usual sense. Most cosmologists accept the Big Bang as describing reality because it is so strongly supported by multiple lines of evidence. That doesn't mean that they would stick to it dogmatically if a better theory comes along... but so far, nothing else comes close to explaining what we observe.

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Devil Particle » Sun Nov 27, 2011 12:19 am

Does this put even a slight dent in Big Bang Theory? I always wonder how much we don't understand. Given that we are born and die and many scientists come from backgrounds involving creation theories isn't there any skepticism within the scientific community that maybe the interpretation of the empirical data is skewed by our natural biases? I mean doesn't this data in some ways suggest that the universe is older than current scientific opinion thinks it is?

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by neufer » Fri Nov 25, 2011 4:52 am

Psnarf wrote:
Which elements produced those absorption lines, or are they from the artist's imagination?
http://arxiv.org/abs/1110.4642 - Red-shifted zinc and sulfur? sulfur
http://arxiv.org/abs/1110.4642 wrote:
<<From the singly ionized zinc and sulfur ... in the blue and red absorber, respectively.>>
Note that the lines in today's APOD are in the blue & yellow.
Ann wrote:
I would guess that the artist hasn't tried to show any of the absorption lines that astronomers actually saw in the spectra from those two galaxies, but instead the artist has shown us a few "generic" absorption lines and reduced the number of them for the sake of clarity.
I agree with Ann. Singly ionized zinc and sulfur would not produce single lines each.

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by bystander » Thu Nov 24, 2011 8:03 pm

Psnarf wrote: http://www.eso.org/public/archives/imag ... o1143b.jpg

Which elements produced those absorption lines, or are they from the artist's imagination?
http://arxiv.org/abs/1110.4642 - Red-shifted zinc and sulfur?sulfur
http://asterisk.apod.com/viewtopic.php?f=31&t=25748

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Ann » Thu Nov 24, 2011 6:31 pm

Psnarf wrote:http://www.eso.org/public/archives/imag ... o1143b.jpg

Which elements produced those absorption lines, or are they from the artist's imagination?
http://arxiv.org/abs/1110.4642 - Red-shifted zinc and sulfur?sulfur
Image
Please note that APOD robot wrote:
the distant galaxies are richer in heavy elements than the Sun, with the highest abundances ever seen in the early Universe.


This is the Solar spectrum. All those little black lines that you can see are absorption lines. So the light from the two distant galaxies showed more absorption lines than the Sun. But today's illustration shows only a few absorption lines in the light from the distant galaxies. Therefore I would guess that the artist hasn't tried to show any of the absorption lines that astronomers actually saw in the spectra from those two galaxies, but instead the artist has shown us a few "generic" absorption lines and reduced the number of them for the sake of clarity.

Ann

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Ann » Thu Nov 24, 2011 6:19 pm

Thank you for the music, Art and Orin! I particularly enjoyed the "Pictures at an Exhibition" piece. It was so beautiful! :D

Ann

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Ann » Thu Nov 24, 2011 5:50 pm

questionman wrote:Could a gamma ray burst like that extinguish all life in that entire galaxy?
As you can see, the gamma ray burst is a narrow jet. I would guess that most inhabited planets in the first galaxy that took a direct hit would fare badly. I'm not sure that most life forms on inhabited planets in the other galaxy, again assuming they took a direct hit, would survive.

I am sure, however, that only a tiny fraction of the planets in both galaxies would actually be hit by that gamma ray burst. I can see no reason why all those planets that weren't hit would suffer any damage.

Ann

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by questionman » Thu Nov 24, 2011 5:14 pm

Could a gamma ray burst like that extinguish all life in that entire galaxy?

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Psnarf » Thu Nov 24, 2011 4:43 pm

http://www.eso.org/public/archives/imag ... o1143b.jpg

Which elements produced those absorption lines, or are they from the artist's imagination?
http://arxiv.org/abs/1110.4642 - Red-shifted zinc and sulfur?sulfur

Re: An Obamma-ray shining through two turkeys.

by neufer » Thu Nov 24, 2011 4:21 pm

Beyond wrote:
It is also mentioned that all three of the absorption lines are the same.
The entire giblet spectrum was observed.

Re: An Obamma-ray shining through two turkeys.

by Beyond » Thu Nov 24, 2011 3:49 pm

It is also mentioned that all three of the absorption lines are the same.

An Obamma-ray shining through two turkeys.

by neufer » Thu Nov 24, 2011 2:57 pm

APOD Robot wrote:Image Caught in the Afterglow

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by neufer » Thu Nov 24, 2011 2:39 pm

OverlordE wrote:
Looks nice and may be what happened but I do not consider an artist’s illustration a picture therefore this should not be listed as the picture of the day. If this is what you want than call it the drawing of the day.
Picture , n. [L. pictura, fr. pingere, pictum, to paint: cf. F. peinture. See Paint.]
Click to play embedded YouTube video.
1. The art of painting; representation by painting. [Obs.]
  • "Any well-expressed image . . . either in picture or sculpture." - Sir H. Wotton.
2. A representation of anything (as a person, a landscape, a building) upon canvas, paper, or other surface, produced by means of painting, drawing, engraving, photography, etc.; a representation in colors. By extension, a figure; a model.
  • "Pictures and shapes are but secondary objects." - Bacon.
3. An image or resemblance; a representation, either to the eye or to the mind; that which, by its likeness, brings vividly to mind some other thing; as, a child is the picture of his father; the man is the picture of grief.
  • "My eyes make pictures when they are shut." - Coleridge.

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by OverlordE » Thu Nov 24, 2011 2:18 pm

Looks nice and may be what happened but I do not consider an artist’s illustration a picture therefore this should not be listed as the picture of the day. If this is what you want than call it the drawing of the day.

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by orin stepanek » Thu Nov 24, 2011 1:27 pm

Click to play embedded YouTube video.

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by Boomer12k » Thu Nov 24, 2011 6:26 am

Would not a smaller universe have more "gravity"?
Would it not have a higher concentration of "Dark Matter"?
Would that not create stars quicker and thus the cycle of star formation, and heavier metals?
Would not the "gamma ray burst" be caused by a massive star?
In a early universe with only lighter elements, could such massive stars form?
My conclusion is "yes", as the universe is smaller and more compacted, thus more relative "pressure" to apply to the processes. But I wonder if this is in "ALL CASES", or just this particular case, and that would make this an anomaly and not the norm.
So, there would appear to have been "greater processes" at work, than have been figured on or assumed.


:--[====] *

Oh Cool, I seem to have been promoted....up there with Spock, now!

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by bactame » Thu Nov 24, 2011 6:07 am

This bit of news was on the Cosmic Mirror a week ago or so and is in the realm of Cosmology of the sort that will interest Penrose and the cyclic cosmologists. Stars in the young universe producing clouds of heavy metals which simple big bang cosmology assumes couldn't have been produced. Zounds.

A cyclic universe cycles into re-birth much faster than simple Big Bangs and thus the observation that the universe is accelerating strongly now fits into the green ecology of use then re-use.

Re: APOD: Caught in the Afterglow (2011 Nov 24)

by neufer » Thu Nov 24, 2011 5:47 am

Click to play embedded YouTube video.

APOD: Caught in the Afterglow (2011 Nov 24)

by APOD Robot » Thu Nov 24, 2011 5:06 am

Image Caught in the Afterglow

Explanation: In this artist's illustration, two distant galaxies formed about 2 billion years after the big bang are caught in the afterglow of GRB090323, a gamma-ray burst seen across the Universe. Shining through its own host galaxy and another nearby galaxy, the alignment of gamma-ray burst and galaxies was inferred from the afterglow spectrum following the burst's initial detection by the Fermi Gamma Ray Space Telescope in March of 2009. As seen by one of the European Southern Observatory's very large telescope units, the spectrum of the burst's fading afterglow also offered a surprising result - the distant galaxies are richer in heavy elements than the Sun, with the highest abundances ever seen in the early Universe. Heavy elements that enrich mature galaxies in the local Universe were made in past generations of stars. So these young galaxies have experienced a prodigious rate of star formation and chemical evolution compared to our own Milky Way. In the illustration, the light from the burst site at the left passes successively through the galaxies to the right. Spectra illustrating dark absorption lines of the galaxies' elements imprinted on the afterglow light are shown as insets. Of course, astronomers on planet Earth would be about 12 billion light-years off the right edge of the frame.

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