2006/11/16 by Nathan Smith · 5 citations
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Gamma-ray bursts and supernovae #Geology #Luminous blue variable #Nebula #Physics #Stars #Stellar, planetary, and galactic studies #Supernova #astro-ph
paper · pdf · doi:10.1086/510838
published as Astron.J.133:1034-1040,2007 · 2 pages, to appear in procedings of "Massive stars: fundamental parameters and circumstellar interactions", conference in honor of Virpi Niemela's 70th birthday
openalex publication_date 2007/02/07 · arxiv created 2007/05/21 · arxiv updated 2010/11/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Spitzer Space Telescope images of the luminous blue variable (LBV) candidate HD 168625 reveal the existence of a bipolar nebula several times larger than its previously known equatorial dust torus. The outer nebula of HD 168625 has a full extent of ∼80'' or 0.85 pc, and one of the lobes has a well-defined polar ring. The nebula is a near twin of the triple-ring system around SN 1987A. Because of these polar rings, and accounting for stellar/progenitor luminosity, HD 168625 is an even closer twin of SN 1987A than the B supergiant Sher 25 in NGC 3603. HD 168625's nebula was probably ejected during a giant LBV eruption and not during a red supergiant phase, so its similarity to the nebula around SN 1987A may open new possibilities for the creation of SN 1987A's rings. Namely, the hypothesis that Sk -69 202 suffered an LBV-like eruption would avert the complete surrender of single-star models for its bipolar nebula by offering an alternative to an unlikely binary merger scenario. It also hints that LBVs are the likely progenitors of some Type II supernovae, and that HD 168625's nebula is a good example of a pre-explosion environment.