We study the molecular outflow of the nearby evolved S star 1 Gru. We imaged the outflow in CO J ¼ 2 1 and dust continuum with the Submillimeter Array. The CO emission was detected over a very broad velocity width of $90 km s À1. Our high-resolution images show that the outflow at low velocities (15 km s À1) is elongated eastwest and at high velocities (!25 km s À1) is displaced north (at redshifted velocities) and south (blueshifted velocities) of center as defined by the dust continuum source. We model the spatial-kinematic structure of the lowvelocity outflow as a flared disk with a central cavity of radius 200 AU and an expansion velocity of 11 km s À1 , inclined by 55 to our line of sight. We attribute the high-velocity component to a bipolar outflow that emerges perpendicular to this disk with a velocity of up to $45 km s À1. This high-velocity outflow may play an important role in shaping the gas envelope previously ejected by the AGB star and thus produce a bipolar morphology when the object evolves into a proto-planetary nebula.

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