Supernova 1987A Progenitor

1. Original source: Arnett, W.D.; et al. (1989). "Supernova 1987A". Annual Review of Astronomy and Astrophysics27: 629–700. From Wikipedia article, downloaded 9/8/14, http://en.wikipedia.org/wiki/SN_1987A : Progenitor Four days after the event was recorded, the progenitor star was tentatively identified as Sanduleak -69° 202, a blue supergiant.[9] This was an unexpected identification, because at the time a blue supergiant was not considered a possibility for a supernova event in existing models of high mass stellar evolution. Many models of the progenitor have attributed the color to its chemical composition, particularly the low levels of heavy elements, among other factors.[10] There has been some speculation that the star may have merged with a companion star prior to the supernova.[11] However, it is now widely understood that blue supergiants are natural progenitors of supernovae, although there is still speculation that the evolution of such stars requires mass loss involving a binary companion.[12] It is of note that the supernova of the blue giant Sanduleak -69° 202 was about one-tenth as luminous as the average observed type II supernova, which is associated with the denser makeup of the star. Since blue supergiant supernovae are not as bright as those generated by red supergiants, we would not expect to see as many of them, and so they might not be as rare or unusual as previously thought.[citation needed] Supernova 1987A Progenitor Additional Resource Hubble Science Briefing: The Real World: Black Hole Edition 9/4/14

2. References • Sonneborn, G. (1987). "The Progenitor of SN1987A". In Minas Kafatos; Andrew Michalitsianos. Supernova 1987a in the Large Magellanic Cloud. Cambridge University Press. ISBN 0-521-35575-3 • Arnett, W.D.; et al. (1989). "Supernova 1987A". Annual Review of Astronomy and Astrophysics27: 629–700. Bibcode:1989ARA&A..27..629A. doi:10.1146/annurev.aa.27.090189.003213 • Podsiadlowski, Philipp, PASP 104:717-729,1992.Podsiadlowski, Philipp (1992). "The progenitor of SN 1987 A". Publications of the Astronomical Society of the Pacific104: 717. Bibcode:1992PASP..104..717P. doi:10.1086/133043 • Dwarkadas, V. V. (2011). "On luminous blue variables as the progenitors of core-collapse supernovae, especially Type IIn supernovae". Monthly Notices of the Royal Astronomical Society412 (3): 1639–1649. arXiv:1011.3484. Bibcode:2011MNRAS.412.1639D. doi:10.1111/j.1365-2966.2010.18001.x Additional Resource Hubble Science Briefing: The Real World: Black Hole Edition 9/4/14