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Fraser
2005-Apr-25, 05:39 AM
SUMMARY: A cross-organizational team of astronomers headed by Arjun Dey of the National Optical Astronomy Observatory (NOAO) has pulled together optical, infrared, and radio-frequency data to probe what may be an expansive galaxy forming region located 11.3 BLY's distant in the direction of the constellation Bootes. The gaseous object (SST24 J1434110+331733), extending some 800 KLYs across space, could significantly advance our understanding of galaxy groups formation in the early universe.

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

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

GOURDHEAD
2005-Apr-25, 01:55 PM
The article states that the only emision line is that of the hydrogen Lyman-alpha radiation which is a likely suspect since at that age, there should not have been much else around in that environment. However it seems risky to me to calculate age on a single emission line rather than a spectrum profile. How shall I be comforted.

There was a mention of dust in part of the nebula, where do they think that came from at such an early age and how did they identify it without emission lines?

Nick4
2005-Apr-25, 03:20 PM
Thats interesting i wonder if you can see it with a telescope. If some one knows if you can or the cordinents for it pleas e-mail me and let me know.

The Near-Sighted Astronomer
2005-Apr-25, 08:02 PM
Greetings Gents,


i wonder if you can see it with a telescope

This one is very faint at best you could have a look at the region of the sky and use you averted imagination.


However it seems risky to me to calculate age on a single emission line rather than a spectrum profile.

As for emission lines there are more than just Lyman alpha - but Lyman alpha is a key marker line for gas and dust (when stimulated by broadbnd radiation from other sources -in this case the AGN within the extended nebulosity). Beyond that frankly you can only use single emission lines to determine red shift because continuous radiation would just shift down from Uv to visible and other than the power spectrum you'd have a hard time telling them apart...

The key to this discovery is the lack of broadband (continuous) radiation - something that is sourced by stellar photospheres due to their thermal properties not their chemical constituents.

Hope you enjoyed the article,

jeff

Duane
2005-Apr-29, 06:59 PM
Nice answer Jeff.