Quick search Find article
Quick search
Find article

Discovery of a Nearby Twin of SN 1987A's Nebula around the Luminous Blue Variable HD 168625: Was Sk −69 202 an LBV?*

FREE ISSUE

Nathan Smith1

Show affiliations


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.


Footnote
*  Based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under NASA contract 1407.
Keywords

circumstellar matter; stars: evolution; stars: individual (HD 168625); stars: mass loss; stars: winds, outflows; supernovae: individual (SN 1987A)


Dates

Issue 3 (2007 March)

Received 2006 September 18, accepted for publication 2006 November 13

Published 2007 February 7



View by subject




Export








Please login to access our web services, or create an account if you don't yet have one.

You must have cookies enabled in your web browser to be able to login.

Username
Password

Forgotten your password? Get a new one here.