Internal motions in planetary nebulae : NGC 7354, I 289 and HU 1-2.
Abstract
The forbidden O III, H I and forbidden N II radial velocity fields within the planetary nebulae NGC 7354, I 289, and Hu 1-2 have been obtained from Echelle spectrograms. The observations indicate that NGC 7354 is a prolate spheroid or a three axes ellipsoid with a central, bright ring or torus of low eccentricity. I 289 consists of a prolate spheroid with major axis almost perpendicular to the line of sight. No conclusive spatial model can be obtained for Hu 1-2 in which the radiation is concentrated in two bright lobes.
- Publication:
-
Astronomy and Astrophysics Supplement Series
- Pub Date:
- January 1983
- Bibcode:
- 1983A&AS...51..119S
- Keywords:
-
- Atomic Spectra;
- Galactic Structure;
- H Lines;
- Oxygen Spectra;
- Planetary Nebulae;
- Radial Velocity;
- Astronomical Models;
- Ellipsoids;
- Forbidden Bands;
- Gas Expansion;
- High Dispersion Spectrographs;
- Interstellar Gas;
- Nitrogen;
- Prolate Spheroids;
- Toroidal Plasmas;
- Visible Spectrum;
- Astrophysics