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Pop. I object

  1. Nov 27, 2007 #1
    Can anybody explain to me what a Pop. I object is?
  2. jcsd
  3. Nov 27, 2007 #2
    The youngest stars, including the Sun, that have the highest metal content, are known as Population I stars.
  4. Nov 27, 2007 #3


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    I guess you answered your own question...

    Anyway, the Population I/II distinction is fairly arbitrary, but is based on an apparent bimodality in the metallicity distribution of the Milky Way. Pop I objects probably formed later than Pop II objects and were therefore made from gas that had already been polluted with a lot of heavy metals (mainly by supernovae). This type of star dominates the thin disk of the Milky Way, while the halo is dominated by Pop II objects.
  5. Nov 27, 2007 #4


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    Some discussions on Pop I and Pop II objects/stars, what they are and where they are:


    http://www.astro.umd.edu/educationalresources/astro/mw/pop.html [Broken]


    So where is the cutoff between Pop I and Pop II in terms of metallicity? 0.1% or 1% metals?

    Interesting how Pop I stars are associated with Type II SN and Pop II stars are associated with Type I SN.

    How Population I and II relate to Galaxies - http://www.astro.psu.edu/users/kluhman/a1/lec25.html [Broken]

    Milky Way Spiral Structure - http://www.seds.org/messier/more/mw_arms.html [Broken]

    http://articles.adsabs.harvard.edu/cgi-bin/nph-build_image?bg=%23FFFFFF&/seri/AJ.../0062/600/0000146.000&db_key=AST&bits=4&res=100&filetype=.gif [Broken]
    Last edited by a moderator: May 3, 2017
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