2007/09/27 by G. Ramos-Larios, M. A. Guerrero, Ramos-Larios, G. +3
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #Astrophysics and Star Formation Studies #FOS: Physical sciences #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.0709.4504
5 pages, proceedings of the conference Asymmetrical Planetary Nebulae IV La Palma, June 18-22 2007
arxiv created 2007/09/27 · openalex publication_date 2007/09/27 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The H2 and optical (Ha, [NII]) morphology of NGC 6881 are very different. Here we present a preliminary report of the analysis of new optical (Ha and [NII]) and near-IR (Brg and H2) images and intermediate resolution JHK spectra of this nebula. Our observations confirm the association of the H2 bipolar lobes to NGC 6881 and reveal that H2 is predominantly shock excited in this nebula. We conclude that NGC 6881 has multiple bipolar lobes that formed at different phases of the nebular evolution and that the collimation conditions or even the collimating agent changed from one ejection to the other.