We consider the subject of time dependence of the Oort cloud comet flux. Over long time scales the flux is likely to be dominated by the adiabatic galactic tide. This tide is substantially modulated as the Solar System moves in its galactic orbit. If Shoemaker was correct in his estimate that virtually all terrestrial craters of diameter > 100 km are produced by long period comets, then the phase and plane crossing period of the Solar System about the galactic disk should be consistent. with the ages of accurately dated large craters. A time series analysis of these ages in which the Solar oscillation phase is fixed to be consistent with observations indicates a maximal correlation for a period of 36 ± 2 Myr. This period is well within observational limits. If improvements in stellar velocity dispersion studies continue, it is possible that a sufficiently accurate determination of the Solar oscillation period can be found to unambiguously answer the following questions. Is the Solar oscillation cycle correlated with the time series of ages for large craters? If so, can we reject the hypothesis that the correlation is an artifact that could likely be reproduced by a random distribution of ages? We present evidence which suggests that if it is found that the data requires a plane crossing period in the range 36 ± 2 Myr, the answer to both of these questions will be affirmative.