We report results from a program of high-resolution spectral mapping ofrotational H_2 emission from bipolar planetary and pre-planetary nebulae.Long-slit spectra obtained with the NOAO Phoenix near-infrared spectrometerallow us to probe the molecular kinematics of these nebulae at moderate spatialresolution. We find strong evidence of a component of rotation in theequatorial H_2 emission from the Egg nebula (RAFGL 2688). In this nebula and inthe pre-planetary nebula RAFGL 618, the H_2 kinematics point to the recentemergence of high-velocity polar flows, which likely mark the fairly suddenterminations of the red giant phases of their central stars. The classicalbipolar planetary NGC 2346 displays distinct kinematic components, which weinterpret as arising in the morphologically distinct equatorial and polarregions of the nebula. The H_2 rings observed in the Phoenix position-velocitymaps of this nebula support the hypothesis that ring-like planetaries thatdisplay H_2 emission possess bipolar structure.
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