2004/07/28 by K. Weis, Kerstin Weis, Weis, Kerstin
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics (astro-ph) #FOS: Physical sciences #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0407569
short review, 5 pages, to appear in conference proceedings "The Fate of the Most Massive Stars", ASP conf series, paper with images in full resolution at http://www.astro.ruhr-uni-bochum.de/kweis/publications.html
arxiv created 2004/07/28 · openalex publication_date 2004/07/28 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The nebula around eta Carinae consists of two distinct parts: the Homunculus and the outer ejecta. The outer ejecta are mainly a collection of numerous filaments, shaped irregularly and distributed over an area of 1arcminx1arcmin. While the Homunculus is mainly a reflection nebula, the outer ejecta are an emission nebula. Kinematic analysis of the outer ejecta (as the Homunculus) show their bi-directional expansion. Radial velocities in the outer ejecta reach up to >2000km/s and the gas gives rise to X-ray emission. The temperature of the X-ray gas is of the order of 0.65 keV. These shock temperatures indicate velocities of the shocking gas of 750km/s, about what was found for the average expansion velocity of the outer ejecta. HST/STIS data from the strings, long, highly collimated structures in the outer ejecta, show that the electron density of the strings is of the order of 104cm-3 Other structures in the outer ejecta show similar values. String 1 has a mass of about 3 10-4M_\sun, a density gradient along the strings or a denser leading head was not found.