Hu 1-2 is a planetary nebula that contains an isolated knot located northwestern of the main nebula , which could be related to a collimated outflow .
We present a subsarcsecond H \alpha + [ N ii ] image and a high-resolution , long-slit spectrum of Hu 1-2 that allow us to identify the southeastern counterpart of the northwestern knot and to establish their high velocity ( > 340 km s ^ { -1 } ) , collimated bipolar outflow nature .
The detection of the northwestern knot in POSS red plates allows us to carry out a proper motion analysis by combining three POSS red plates and two narrow-band H \alpha + [ N ii ] CCD images , with a time baseline of \simeq 57 yr. A proper motion of 20 \pm 6 mas yr ^ { -1 } along position angle 312 ^ { \circ } \pm 15 ^ { \circ } , and a dynamical age of 1375 ^ { +590 } _ { -320 } yr are obtained for the bipolar outflow .
The measured proper motion and the spatio-kinematical properties of the bipolar outflow yield a lower limit of 2.7 kpc for the distance to Hu 1-2 .