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Here we present initial results of our search for extensive halos around theplanetary nebulae (PNe) in our Galaxy based on imaging data from the SouthernH-Alpha Sky Survey Atlas (SHASSA). A threshold surface brightness in H$\alpha$emission was used to help identify the spatially extended features of the PNe.We investigated a sample that included 10 PNe, the large majority of which werefound to be surrounded by extensive outer halos. The formation of these halosmight be closely related to the AGB phase mass loss and/or the interaction ofthe stellar outflows with the interstellar medium. Most of these outer halosare nearly spherical. Close investigation of some specific objects, such as He2-111 and NGC 3242, indicate a kinematic age on the order of 10$^{5}$ yrs. Themass loss history can be traced back to the late AGB phase of the evolution ofthe progenitors. Two objects form the sample (He 2-111, NGC 3242), were foundto have outer halos with fragmented arcs that are apparently the result oftheir interaction with the interstellar medium.

The H$\alpha$ Halo Distribution of 10 Nearby Planetary Nebulae based on the SHASSA Imaging Data