Deep Impact Testing Update - January 25, 2003 CML Yesterday (Friday, January 24, 2003) the HRI/MRI flyby instrument package was vibration tested on the second of its 3 axes, in random and frequency sweep mode. While a noticeable resonance for the structure was seen at 40 Hz, all results of the tests so far seemed positive. The primary mirrors did well. On Thursday, January 23, 2003, the Ball staff were queried as to the feasibility of including a gas cell in the illumination path for the IP tests of the SIM module. They agreed that there is room for the cells to be included, and that this would be added into the testing plan. The decision to put the ITS in the vacuum chamber was made after another series of tests into the ITS focusing. The results of focus testing on January 23, 2003 were more positive than previous measurements - the subtracted images looked much cleaner, with no secondary source spot or structure in the background, as were seen, for example, in the January 21, 2003 datasets. The pinhole PSF radius reached a simple parabolic minimum somewhere between -1 and -2 mm; the knife-edge tests had minima at -1 for the horizontal, +2 mm for the vertical, with some structure to the minima. Previous results had been -6 horizontal, +3 vertical. Although the RMS of the knife edge tests seems to be about the not too different from the RMS from the pinhole centroiding, the persistent discrepancy between the best horizontal and vertical focus positions is still an issue. There is some question that the knife edge test may sample more of the detector than the pinhole. The "black tub straylight blocker" image dependence was found to have disappeared. As various illumination sources gave the same difficult results before the 23rd, the problem appears to have been in the GSE collimator system, but this has not been fully explored at this time, due to schedule constraints. In severely defocused pinhole illumination experiments, the three-fold symmetry of the ITS secondary spider was clearly seen. A test of the calibrated light source + integrating sphere with a warm ITS demonstrated the need for ND filters during TV3 to generate non-saturated images. On Friday afternoon, the ITS instrument package was brought from the clean room and installation was begun into the Ball 8 vacuum chamber. The package was left under N2 purge overnight. Cable hookup and safe-to-mating is proceeding this morning, Saturday January 25, 2003. The chamber is expected to be closed by early afternoon, whereon a 48 hour period of bakeout will commence. Cool down should then begin Monday afternoon, and calibration testing on Tuesday morning. ITS Testing Staffing : Tim Cline will be leaving the afternoon of Monday, January 27. Dennis Wellnitz will be arriving the evening of Wednesday, January 29th. Casey Lisse will be leaving the morning of Friday, January 31. Bill Smythe is at Ball now; he plans to be here for the next few days, return to JPL, then come back for the end of the testing. Some coordination with him concerning the latest testing schedule should be beneficial.