A Space & astronomy forum. SpaceBanter.com

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   Home » SpaceBanter.com forum » Others » Misc
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Iron and the Stars



 
 
Thread Tools Display Modes
  #1  
Old June 29th 03, 07:08 PM
J. Scott Miller
external usenet poster
 
Posts: n/a
Default Iron and the Stars

G=EMC^2 Glazier wrote:
The last days of our sun will be when all its fusion fuel is just about
used up and finds the iron nucleus is to tightly held together ,and
fusion can't take place. The star"s core has been transmuted into iron.
Iron atoms in the universe should be very long lasting. How much iron
does the sun have now? Is there more iron in the solar system than iron
in the sun? Bert


I'm going to kick myself for responding, but:

The Sun will NOT have a core that was transmuted to iron. It lacks the mass to
drive to that process. At best, helium fusion will lead to the formation of
carbon and oxygen. But there is insufficient mass in the core to compress and
heat this inert mass to the point where it will fuse. Instead, the outer
atmosphere will be puffed off over time to form a planetary nebula while the
inert carbon/oxygen core cools to become a white dwarf.

The estimated iron content of the Sun is about 0.1 percent of its mass.

Ads
  #2  
Old June 29th 03, 07:35 PM
David Knisely
external usenet poster
 
Posts: n/a
Default Iron and the Stars

Bert posted:

The last days of our sun will be when all its fusion fuel is just about
used up and finds the iron nucleus is to tightly held together ,and
fusion can't take place. The star"s core has been transmuted into iron.


Bert, the sun isn't massive enough to fuse elements heavier than Helium
because the sun doesn't have enough mass to get the core temperature up
to that level. Fusion in the core will stop when it has exhausted its
supply of core helium and shell Hydrogen, leaving the sun to contract
into a white dwarf star made mostly of carbon with a thin upper layer
containing lighter elements (some of the original small amounts of Iron
which is in the sun today may be still be around in the core). To get
much iron produced by fusion in the core of a star requires it to have a
*much* higher mass than the sun does.
--
David W. Knisely
Prairie Astronomy Club:
http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

**********************************************
* Attend the 10th Annual NEBRASKA STAR PARTY *
* July 27-Aug. 1st, 2003, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************
  #3  
Old June 30th 03, 12:25 PM
G=EMC^2 Glazier
external usenet poster
 
Posts: n/a
Default Iron and the Stars

Hi Scott Instead of kicking yourself let me pat you on the back,and
thank you. I needed that information about the amount of iron in the
sun. Using the amount of iron in our sun as a reference frame and
comparing it with stars like our sun we can tell how old they are,and
their future. Bert

  #4  
Old July 5th 03, 01:14 PM
G=EMC^2 Glazier
external usenet poster
 
Posts: n/a
Default Iron and the Stars

Hi Scott You did not like the sun's core transformed into an iron
core(yes) What will be the percentage of iron in its core in 5 billion
years when the sun is transformed into a red giant? Could we say the
iron atoms make it red? Is it red hot like a red hot poked? Thanks in
advance Bert

  #5  
Old July 5th 03, 07:48 PM
David Knisely
external usenet poster
 
Posts: n/a
Default Iron and the Stars

Bert posted:

You did not like the sun's core transformed into an iron
core(yes)


Bert, he didn't like it because it doesn't happen! The sun is not
massive enough to produce iron in the fusion process. The sun will
eventually run out of Helium to fuse in its core and will contract into
a white dwarf with a core that is mostly made of Carbon (and maybe some
Oxygen, plus any residual amounts of iron left over from the original
composition of the sun).
--
David W. Knisely
Prairie Astronomy Club:
http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

**********************************************
* Attend the 10th Annual NEBRASKA STAR PARTY *
* July 27-Aug. 1st, 2003, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************
 




Thread Tools
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

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 03:52 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Copyright 2004-2019 SpaceBanter.com.
The comments are property of their posters.