Abstract
Optical spectroscopy of the entire planetary nebula M 1-9, reveals pronounced density variations, a temperature distribution where T_e (N(+) ) is larger than T_e (O(+2) ) and abundances indicating that it is a halo planetary nebulae, an association supported by it is very large radial velocity and distance to the galactic plane. The ionized mass is between 0.1 and 0.4 M_⊙ . A uniform density photoionization model (Cloudy, version 10.00) reproduced most of the spectrum, but the intensity of [O III] 4363 Å is much larger than observed. In this model, nebular abundances are smaller than those derived using standard techniques and the stellar temperature and luminosity are 84900°K and 1025 L_⊙, which implies that the progenitor probably was a ≈1 M_⊙ zero-age main sequence star.
