Predictions for LRO Jan McGarry

1. Predictions for LRO Jan McGarry • Will most likely be generated by LRO Orbit Determination Team. We will ask the LOLA Science Team to also generate predictions – at least initially – as check. • Will request predictions be in CPF format. • To synchronize with LOLA laser fire we will need: - Determination of range-rate (compute from positions and/or velocities). - LRO UTC offset and LRO oscillator drift (embedded in CPF Header Type 4 - Transponder Info). - Delay of range window relative to T0: use transponder transmit delay field or generate new field???

2. One LOLA detector does both earth uplink and lunar surface • Two range windows in one detector: 8 msec earth and 5 msec lunar. • Need to minimize the earth events in the lunar surface window to prevent on-board signal processing algorithm from following the wrong signal. • This can be achieved by synchronizing the ground laser fires to LOLA (LRO timing and range-rate of spacecraft), OR by low frequency laser fire rates. Start of LOLA laser fire period (T0) LOLA laser fires (~ 9ms after T0) Start of next LOLA laser fire period 35.7 msec (28 Hz)