Chatroom
 

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Bad Astronomy and Universe Today Forum > Universe Today > Universe Today Story Comments
Register FAQ Members List Calendar Mark Forums Read

   

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 23-September-2004, 05:58 PM
Fraser's Avatar
Fraser Fraser is offline
Administrator
 
Join Date: Jul 2003
Location: Courtenay, BC, Canada
Posts: 13,021
Default

SUMMARY: Astronomers have been studying the deepest optical view of the Universe - the Hubble Ultra Deep Field (HUDF) - and they think they've found some of the first star forming galaxies. These galaxies began forming 0.5 to 1 billion years after the Big Bang. The team analyzed the HUDF, and found dozens of red, dim dwarf galaxies, which appear to be the first basic galactic building blocks. These would merge with other galaxies to eventually form the complex spiral formations like our own Milky Way. The also found regions which were more dense than others, which supports the theory that dense regions of space where the first places galaxies formed.

What do you think about this story? Post your comments below.
Reply With Quote
  #2 (permalink)  
Old 23-September-2004, 07:51 PM
om@umr.edu om@umr.edu is offline
Banned
 
Join Date: Nov 2003
Posts: 1,234
Default

Another great story, Fraser.

I was unable to find if the composition of the material they see, at 95% of the time back to the "Big Bang", matches the composition of "primordial Big Bang products"?

Or do they find Fe, O, Ni and Si that were supposedly produced later?

With kind regards,

Oliver
http://www.umr.edu/~om
Reply With Quote
  #3 (permalink)  
Old 23-September-2004, 08:06 PM
StarLab
Guest
 
Posts: n/a
Default

Quote:
The also found regions which were more dense than others, which supports the theory that dense regions of space where the first places galaxies formed.
I think that's logical.
Reply With Quote
  #4 (permalink)  
Old 23-September-2004, 08:15 PM
Ola D.'s Avatar
Ola D. Ola D. is offline
Established Member
 
Join Date: Apr 2004
Posts: 642
Send a message via MSN to Ola D.
Default

How much dense is our galaxy? Is it among the most dense?
Reply With Quote
  #5 (permalink)  
Old 23-September-2004, 11:38 PM
antoniseb's Avatar
antoniseb antoniseb is online now
Administrator
 
Join Date: Jul 2005
Location: Berlin MA
Posts: 16,013
Default

Quote:
Originally posted by Ola D.@Sep 23 2004, 07:15 PM
How much dense is our galaxy? Is it among the most dense?
Our galaxy, including its halo, appears to have a mass of about 6x10^44 grams, which would be about 4x10^68 atoms since it is mostly Hydrogen.

It has a volume of 4x10^67 cubic centimeters [counting the disk and bulge, but not the halo] So, including stars, dust, black holes, dark matter, etc, the galaxy has a density of about 10 protons or neutrons per cubic centimeter.

This is roughly the same as most nearby galaxies with central bulges.
__________________
Forming opinions as we speak
Reply With Quote
  #6 (permalink)  
Old 24-September-2004, 12:33 AM
StarLab
Guest
 
Posts: n/a
Default

Yeah, Ola, it's pretty avg.
Reply With Quote
  #7 (permalink)  
Old 24-September-2004, 07:00 PM
om@umr.edu om@umr.edu is offline
Banned
 
Join Date: Nov 2003
Posts: 1,234
Default

Density doesn't provide the kind of quantitative information we need to deciper this observation.

We need to know if the composition of the material is He and He, as expected for the composition of "primordial Big Bang products"?


Or does it contain more evolved matter with Fe, O, Ni and Si?

With kind regards,
Oliver
http://www.umr.edu/~om
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT. The time now is 09:23 PM.


Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
LinkBacks Enabled by vBSEO 3.0.0
©  2006 Bad Astronomy and Universe Today