Open slit echelle spectroscopy of planetary nebula M 1-9

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-circle dot. A uniform density photoionization model (Cloudy, version 10.00) reproduced most of the spectrum, but the intensity of [O III] 4363 angstrom 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 degrees K and 1025 L-circle dot, which implies that the progenitor probably was a M-circle dot zero-age main sequence star.