QUOTE (Alan Stern @ Jan 25 2006, 03:10 PM)
C/A was 185,000 km or so to Luna. Had we launched 21 Jan, it would have been about 10x closer. And yes, our modeling takes lunar gravity into account when computing the launch targets.
In fact, IIRC, lunar perturbations factored into computing a new launch date for Cassini, which was delayed from the originally scheduled launch date due to Huygens-related work on the pad. Due to tight pre-launch estimates of propellant margins, mission planners were worried that too close a lunar flyby would have perturbed the trajectory outbound to Venus-1, requiring a propellant expenditure. And there was a point during the launch period when the Moon was in "the wrong position," so, from what I understand, the new launch date was scheduled when the Moon was no longer "in the way." Of course, virtually perfect navigation during VVEJGA/cruise has given more than adequate margin at Saturn.