The latest tilt data taken May 8-9, 2000, while tracking RCW 57.
Compare this with the March 20-21 tilt data:
Recall the equation for arbitrary azimuth, which is
arbitrary-az = 15*(UT - RA) + d/365
Since RA is constant to within the effect of two months of luni-solar
precession, as d increases, UT must decrease for constant arbitrary az.
This means that the peaks of the tilt curve must move forward with
respect to time of day as date advances. Furthermore, since there are
50 days between March 20 and May 9, the curve must move forward by
about 0.15 days. Upon comparison of the two curves, it can be seen
that the displacement between the two curves is in the correct direction
and by the amount expected, and that the magnitude of the effect seems
fairly stable.