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We present results of VLBI observations of the water masers associated withIRAS 4A and IRAS 4B in the NGC 1333 star-forming region taken in four epochsover a two month period. Both objects have been classified as extremely youngsources and each source is known to be a multiple system. Using the Very LongBaseline Array, we detected 35 masers in Epoch I, 40 masers in Epoch II, 35 inEpoch III, and 24 in Epoch IV. Only one identified source in each systemassociates with these masers. These data are used to calculate proper motionsfor the masers and trace the jet outflows within 100 AU of IRAS 4A2 and IRAS4BW. In IRAS 4A2 there are two groups of masers, one near the systemic cloudvelocity and one red-shifted. They expand linearly away from each other atvelocities of 53 km/s. In IRAS 4BW, masers are observed in two groups that areblue-shifted and red-shifted relative to the cloud velocity. They form complexlinear structures with a thickness of 3 mas (1 AU at a distance of 320 pc) thatexpand linearly away from each other at velocities of 78 km/s. Neither of thejet outflows traced by the maser groups align with the larger scale outflows.We suggest the presence of unresolved companions to both IRAS 4A2 and 4BW.

Time-Resolved AU-Scale Jets Traced by Masers in the IRAS 4A/B Regions of NGC1333