This morning Silviu measured the vacuum motion of the target before the cooldown started. I forget exactly what his numbers were, but they were around 2 to 2.5 mm down. He wrote them down and will make a log entry about it tomorrow, I'm sure.
Since the target is now essentially cold, at around 25 K, we went down and measured where it is now that we also have essentially the full effect of thermal contraction. Incredibly, the transit crosshairs are exactly where they were before we pumped out the chamber and cooled down. That means to better than 0.1 mm the thermal contraction exactly cancels the vacuum motion. A surprising but welcome coincidence. A very nice situation because now we don't have to make any corrections to the surveyed positions.