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Redshift, Blueshift

  1. Apr 24, 2005 #1
    :surprised Since we have been taken readings of redshift, blueshift for sometime now, is there a concensus on a percentage of each?
  2. jcsd
  3. Apr 24, 2005 #2
    You need to be a LOT more specific. If you mean measurements of cosmological expansion, all measurements are redshifted. If you mean the local volume, then they are dependent on local motions and I don't know the mix.

    What are you asking?
  4. Apr 24, 2005 #3
    novice at astronomy

    In short I guess what I'm trying to ask is , besides the Andromeda galaxy, are there any other large bodies coming our way, or are they all expanding outward from us?
  5. Apr 25, 2005 #4
    I believe there are at least another two galaxies approahing us.
    They are fairly local.
    You could try nasa site or NED, to ask your question.
    Last edited by a moderator: Apr 25, 2005
  6. Apr 29, 2005 #5
    http://nedwww.ipac.caltech.edu/cgi-bin/nph-allsky?ra_constraint=Unconstrained&ra_1=&ra_2=&dec_constraint=Unconstrained&dec_1=&dec_2=&glon_constraint=Unconstrained&glon_1=&glon_2=&glat_constraint=Unconstrained&glat_1=&glat_2=&z_constraint=Less+Than&z_value1=0&z_value2=&z_unit=km%2Fs&ot_include=ANY&ex_objtypes1=Clusters&ex_objtypes1=Supernovae&ex_objtypes1=QSO&ex_objtypes2=AbsLineSys&ex_objtypes2=GravLens&ex_objtypes2=Radio&ex_objtypes2=Infrared&ex_objtypes3=EmissnLine&ex_objtypes3=UVExcess&ex_objtypes3=Xray&ex_objtypes3=GammaRay&nmp_op=ANY&out_csys=Equatorial&out_equinox=B1950.0&obj_sort=RA+or+Longitude&zv_breaker=30000.0" [Broken] lists 2189 blue-shifted objects.
    Last edited by a moderator: May 2, 2017
  7. May 4, 2005 #6


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    Seems that the Milky Way is already colliding with another galaxy and there are a few more on the way.
    http://curious.astro.cornell.edu/question.php?number=386 [Broken]

    The Andromeda galaxy collision will just be much more significant.

    The Milky Way is part of a "Local Group" of galaxies which are not expanding away from each other (galaxies tend to be found in clusters).
    http://www.seds.org/messier/more/local.html [Broken]
    Last edited by a moderator: May 2, 2017
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