observations of the “ water fountain ” IRAS 16552 − 3050

We present Very Large Array (VLA) observations of the water maser emission towards IRAS 16552-3050. The maser emission shows a velocity spread of ≃ 170 km s, and a bipolar distribution with a separation between the red and blueshifted groups of≃ 0.08. These observations and the likely post-AGB nature of the source indicate that IRAS 16552-3050 can be considered as a member of the “water fountain” class of sources (evolved stars showing H2O maser emission with a velocity spread & 100 km s, probably tracing collimated jets). The water maser emission in IRAS 16552-3050 does not seem to be associated with with any known optical counterpart. Moreover, this source does not have a nearIR 2MASS counterpart, as it happens in about half of the water fountains known. This suggests that these sources tend to be heavily obscured objects, probably with massive precursors (& 4−5 M⊙). We suggest that the water maser emission in IRAS 16552-3050 could be tracing a rapidly precessing bipolar jet. Subject headings: masers – stars: AGB and post-AGB – stars: individual (IRAS 16552−3050) – stars: mass loss – stars: winds, outflows