Distance estimates

Distance estimates - treatment Hanes 1981(MNRAS and...

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Distance estimates Distances to nearby galaxies are not in serious dispute, but the role of peculiar velocity on these scales is. Some useful distances are (in Mpc) Object Distance LMC 0.05 M31 0.68 M81 group 3.2 Sculptor group 3-3.5 M101 4-5 Virgo core 14-18 Coma cluster 100 This means that H(Virgo) is about 60 km/s Mpc, but is this value globally applicable? Two major camps long existed: Sandage at 50 (the "long" distance scale) and de Vaucouleurs at 100 (the "short" scale). Data occasionally drown in invective on this issue. Doing a systematic error
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Unformatted text preview: treatment, Hanes 1981 (MNRAS) and Rowan-Robinson in his book found that 80 km/s Mpc satisfies all the error bars and is what the IR T-F relation gives at large distances. This is essentially the Key Project global value as well, with the CMBR global fitting giving a value of 71. Maybe the compromise value of 75 that many people have used was actually more than fence-sitting....
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