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Fraser
2005-Mar-02, 06:12 PM
SUMMARY: How do you hide some of the brightest galaxies in the Universe? Behind a shroud of dust, of course. NASA's Spitzer space telescope has uncovered a strange class of galaxies which are incredibly bright - shining with the light of 10 trillion suns - but obscured behind a thick veil of dust and gas. So, why are they so dusty? The dust is churned out by stars, but it's strange how well distributed it is. It could be that all galaxies started out this dusty, and then became clearer over time, or maybe the massive black hole at their center has something to do with it.

View full article (http://www.universetoday.com/am/publish/spitzer_hidden_galaxies.html)

What do you think about this story? Post your comments below.

antoniseb
2005-Mar-02, 09:40 PM
There's a lot of reason to think that this sort of object will be an important piece in the puzzle of how stars and galaxies form. I think that the uniformity of the distribution of this dust suggests that it may be spraying rapidly out of a a super-star in the center, which will soom become the central black hole. This is speculation, but whatever the observations end up telling us about this dust, and how it is flowing will be very important to our understanding of the early [20 > z > 6] universe.

wstevenbrown
2005-Mar-03, 02:57 AM
Less than 5 Gyr old, and already spraying silicon! This speaks of some very massive Population III objects, evolving very quickly-- silicon is produced by sequential fusion operations, and low-mass objects couldn't produce large quantities quickly.

One highly speculative way to speed up evolution at early epochs would be to include starseeds and galaxy seeds in the first moments of the bang-- black holes of various sizes and masses to provide condensation centers.

Those hypothetical primordial black holes would not have begun life composed of matter as we currently apprehend it. They would appear more like fundamental 'particles' whose only observable qualities would be mass and spin. In their essence, they were the leftovers of the pre-bang universe, which did not fully participate in the symmetric phase shift that created all the familiar H, He, and Li.

If, as conventional theory holds, the initial BB products were almost completely hydrogen with a soupcon of helium and the ghost of lithium, why would any of these stick to each other and condense to form massive objects unless they were already cold and dense? They wouldn't. There was no dust. And they weren't cold. Local eddies, quantum fluctuations, and other euphemisms don't account for such rapid growth and maturation of galaxy-scale objects. I would concede, tho, that in a younger and denser universe, the first massive stellar object could have begun a rapidly-expanding spherical shell of hypernovae. At 4 million years per generation, such a blast wave could propagate for awhile. It begs the question how the first one formed, tho.

Time for my medication again... S

Eric Vaxxine
2005-Mar-03, 03:18 PM
OK...I'm no scientist, but it seems that this cannot be explained, then?