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Local Group

 

This is  a follow-up to the 3/18 post about the Andromeda group being unique. There are no blue shift objects in the universe outside of our Local Group.
This exercise checks the local group.
I found a reference for the local group. It had 35 objects with their right ascension, declination, relative velocity, estimated distance.

Of the 35, 16 had blue shift, 11 had red shift, 8 were missing that value.
There are several objects with a blue shift and they are relatively near Andromeda, both in position and distance.

This is just a coarse analysis of the local group motions.
Andromeda galaxy M31 has a relative velocity of -301
according to the reference, with no units in the chart.

link
( https://arxiv.org/ftp/astro-ph/papers/9908/9908050.pdf )

However other references for this velocity indicate M31 is at -110 km/sec; I do not know why there is a difference.
Rather than recalculating another's numbers I left them as published. From the paper, a change was possibly done to the values to compensate for solar velocity. I have no reference with original values.
This exercise is only relative velocities and relative positions.
This is a preliminary analysis based on what is available.

key:
Vr = velocity as relative value; + is red shift or recession.
D2 = distance to object, in Mpc
Vr=M = missing data

DEG is dwarf Elliptical Galaxy
DIG is dwarf Irregular Galaxy
DS is dwarf spherical galaxy

This is the spread around the local group, relative to M31, starting at the opposite point in azimuth so M31 is roughly in the middle of the list. There are 35 objects in the reference; their order was by RA.
M31’s right ascension is 00h 42m; its declination is 41d 16m
AD values are from object to M31, to nearest hour or degree

D+ value indicates object has higher declination than M31.
name / position relative to M31 / vel. / distance
DDO 199 A-9h D+26d Vr=-247 D2=0.06
DDO 208   Ah Dd  Vr=-293  D2= 0.08
sagittarius-DS   A-6h D71d  Vr=+142  D2= 0.03
SAG-DIG   A-5h D-58d  Vr=-79  D2= 1.40
NGC 6822   Ah D-55d  Vr=-56  D2= 0.50
DDO 210   Ah Dd  Vr=-131  D2= 1.02
Tucana-DS  A-4h D-105d Vr=M D2=0.87
And VII  A-1h  D9d  Vr= M  D2=0.69
DDO 216  Ah Dd  Vr=-182  D2= 0.76
And VI  A-1h D-17d  Vr=M  D2= 0.83
DDO221  A0h D-56d  Vr=-120  D2= 0.93
UGC 192  A0h D+18d  Vr=-344  D2= 0.66
NGC 185  A0h D-7d  Vr=-193  D2= 0.66
And III  A0h D-5d  Vr=M  D2= 0.76
NGC 185  A0h D+7d  Vr=-202  D2= 0.22
NGC 205  A0h D0d  Vr=-244  D2= 0.76
M32  A0h D0d  Vr=-205  D2= 0.76
M31 Andromeda   A0h D0d  Vr=-301  D2= 0.76
And I   A0h D-3d  Vr=M  D2= 0.81
SMC a0h d-113d  Vr=148 D2= 0.06
Sculptor   A+1h D-74d  Vr=+110  D2= 0.09
LGS 3   A+1h D-20d  Vr=-286  D2= 0.81
IV1613   A+1h D-39d  Vr=-232  D2= 0.72
And V   A+1h D+6d  Vr=M  D2= 0.81
And II   A+1h D-8d  Vr=M  D2= 0.70
M33   A+1h D-11d  Vr=-181  D2= 0.79
PhoenixDS   A+1h D-85d  Vr=M  D2= 0.4
Fornax DS   A+2h D-75d  Vr=+53  D2= 0.14
LMC   A+5h D-110d  Vr=+275  D2= 0.05
Carina   A+6h D-91d  Vr=+223  D2= 0.10
Leo A DDO 69   A+9h D-71d  Vr=+24  D2= 0.69
Leo I DS   A+10h D-29d  Vr=+287  D2= 0.25
Sextans DS   A+10h D-42d  Vr=+226  D2= 0.09
Leo II DDO 93   A+11h D-19d  Vr=+76  D2= 0.21
UrsaMi DDO 199   A+15h D+26d  Vr=-247  D2= 0.06
Draco DDO 208   A+17h D+26d  Vr=-293  D2= 0.08
sagittarius-DS   A+18h D-71d  Vr=+142  D2= 0.03

I find other references to these recent additions to the Local Group but they are not in the reference for the data above:
Canis Major Dwarf
Sagittarius DEG
Tucana II

I can revisit this analysis after finding a better data set; since this data set is incomplete I wonder if research is archived for public research.

Added (03/21/2019)
Last updated (03/21/2019)

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