So, here's a diagram with some galaxies.

I realize there are 500 billion galaxies out there (likely many more), but is there are fairly up-to-date diagram of all the galaxies, or a representative sample, at all observable distances?

Hubble Diagram

  • $\begingroup$ Not sure from the wording of your question, but just in case this isn't clear, you shouldn't expect to have millions of datapoints, you need both a $z$ (easy to measure, we have this for millions of galaxies) and a $z$-independent distance measure (this is harder, current datasets have roughly between a few and a few thousand points, depending on the distance measure). $\endgroup$ – Kyle Oman Jun 11 '14 at 23:26

This diagram is usually called the Hubble diagram. Here is the Hubble diagram from the Hubble Space Telescope Key Project to Measure the Hubble Constant (Freedman et al. 2001):

Freedman et al. 2001 Hubble diagram

The HST Key Project was intended to measure the Hubble constant to high precision using multiple techniques (listed in the legend). Therefore it is constrained to close distances on the cosmological scale (d < 400 Mpc, or z < 0.1).

Ned Wright has presented a Hubble diagram based on the work of Conley et al. (2011), which extends to high redshift and shows the deviation from models without a cosmological constant:

Wright figure based on Conley et al. 2011

  • $\begingroup$ I was somewhat expecting the acceleration of expansion to be obvious from a current Hubble diagram. Is that a naive expectation? $\endgroup$ – MikeHelland Jun 11 '14 at 21:39
  • $\begingroup$ Good point, the HST Key Project was fairly local in scope. I have added another source. $\endgroup$ – coneslayer Jun 11 '14 at 21:54

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