Joe Hennawi (Berkeley) gave a nice talk on the clustering of quasars, and on what can be learned about quasar impact on environment from quasar pairs close on the sky (but not in redshift). There is a big mystery about the proximity effect—in the transverse direction there is lots of absorption by neutral gas, but along the line of sight the quasar ionizes everything—which either means that things are very anisotropic or quasar lifetimes are super-short, I think. We spent time afterwards discussing clustering at small scales, because his work has a lot of overlap with that of Masjedi.
I failed to mention that Dave Monet (USNO) sent me all the data upon which the USNO-B1.0 catalog was constructed. This is yet another respect in which Monet is a great scientist, contributing always to the public good! Now we'll see if the astrometry.net crowd is crazy enough to do anything serious with these data...
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