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Fraser
2006-Oct-13, 05:57 PM
The latest image released from the Hubble Space Telescope shows a beautiful view of a large galaxy being assembled from a collection of small galaxies. The large galaxy, officially known as MRC 1138-262, but nicknamed the Spider Galaxy, contains dozens of smaller star-forming galaxies. It's incredibly far away, 10.6 billion years, so we see it as it looked only 3 billion years after the Big Bang. These observations match commonly held theories about how small irregular galaxies merge together to form the larger structures we see today.

Read the full blog entry (http://www.universetoday.com/2006/10/13/hubbles-sees-galaxies-under-construction/)

antoniseb
2006-Oct-14, 11:02 AM
It isn't clear to me from this image whether we are seeing several small galaxies, or one large galaxy that has several regions under-going high rates of star formation. We'll need to hee the 21-cm image of this galaxy, to be sure.

Hamilcar
2006-Oct-18, 05:43 PM
It isn't clear to me from this image whether we are seeing several small galaxies, or one large galaxy that has several regions under-going high rates of star formation. We'll need to hee the 21-cm image of this galaxy, to be sure.

How are you going to get HI data on a high-z galaxy? You'll have to wait for SKA to do that.
What would an HI map tell you anyway?

antoniseb
2006-Oct-18, 07:15 PM
I agree that we'll need SKA for that, and even then we probably won't get a sufficiently detailed map of *this* galaxy to tell us. What some hypothetical super-interferometer looking at 130-cm z~6 HI data could tell us is whether the several seeming small galaxies in this image are isolated bright spots in one large structure, or whether they are, as described in the caption, isolated galaxies in a small cluster.

RussT
2006-Oct-20, 10:30 AM
This looks like a typical case of see what they want to see and leaping to conclusions.
This looks very Stephen's Quintetish to me and this is 10 Gly away!

I saw a more detalied repot 'somewhere' that said only 2 out of the so called dozens haad the ame confirmed redshift, and the rest of the 'apparent interaction' was inferred.

In every pic that shows collisions, just look at how many are not colliding.

antoniseb
2006-Oct-20, 12:40 PM
This looks very Stephen's Quintetish to me and this is 10 Gly away!
There are some aspects of the blurry little image that look sort of like parts of Stephan's Quintet, but that may be sort of like the face on Mars illusion. To the degree that the article offers some conclusions on what is being seen, I agree that later more detailed observations may lead to different conclusions on this system.

RussT
2006-Oct-21, 10:33 AM
[I agree that later more detailed observations may lead to different conclusions on this system.]

Yes, and to classify this as a single galaxy is wayyyyy premature!

[The Spiderweb Galaxy is located in the southern constellation of Hydra (the water snake), and is one of the most massive galaxies known.]

antoniseb
2006-Oct-21, 01:18 PM
Yes, and to classify this as a single galaxy is wayyyyy premature!
So is ruling it out.

Jerry
2007-Jun-26, 06:30 PM
[I agree that later more detailed observations may lead to different conclusions on this system.]

Yes, and to classify this as a single galaxy is wayyyyy premature!

This is not helpful.

During my adult lifetime, there have been many, many fuzzy dots in photos with captions solemnly stating these are fuzzy new galaxy just eons away from a time when there were no galaxies...

...Only to learn that the next generation of optical clarity pushed the fuzzy zone further into the past. There is considerable evidence out there that puts hierarchical galaxy formation models in jeopardy:

http://arxiv.org/PS_cache/astro-ph/pdf/0605/0605123v1.pdf


Despite the above successes in matching the global behaviour of galaxy evolution, when one focuses on the observed proportion of red/blue galaxies, it is found that current hierarchical models underestimate the number of luminous/massive red galaxies...At higher
redshift the problem is even more severe...

In the referenced paper, they go on to propose a complex feedback mechanism that attempts to resolve the problem. Finding a single example in deep space that looks like what was expected [as they have in this NASA article], while ignoring the 'deep red problem' is cherry picking, not critical analysis of the universe we are observing.

Peter Wilson
2007-Jun-26, 11:37 PM
I'm tired of fuzzy photos being offered up as "proof" of galaxy mergers...where's the hard evidence?

;)

antoniseb
2007-Jun-26, 11:48 PM
I'm tired of fuzzy photos being offered up as "proof" of galaxy mergers...where's the hard evidence?
You mean like an in situ probe collecting and bringing back samples?

Peter Wilson
2007-Jun-27, 06:19 PM
It was an obtuse reference to here (http://www.bautforum.com/showthread.php?t=57976) where the skeptics are bemoaning UFO reports because, "Why there are no fuzzy photos?" :)