Will V445 puppis become a Ia supernova? 6 December 2010, By Jon Voisey observations early the next year showed the ejecta lacked the helium emission seen in classical novae in which hydrogen piles up on a white dwarf surface until it undergoes fusion into helium. Instead, astronomers saw lines of iron, calcium, carbon, sodium, and oxygen expanding at nearly 1,000 km/sec. This fit better with a proposed type of explosion where, instead of hydrogen collecting on the dwarf's surface, it was helium and the eruption seen was a helium flash in which it was helium that underwent fusion. Slowly the star faded, and debris from the eruption cooled to form dust. Today, the star itself is completely obscured in the visible portion of the spectrum. The 2009 paper by Woudt, Steeghs, and Karowska that Nancy cited, suggested accretion might continue until the white dwarf passed the Chandrasekhar limit and exploded as a type Ia supernova. However, the authors of the new paper, led by V. P. Goranskij at Moscow University, say As the "V" in the designation of V445 Puppis that this 2000 detonation has effectively ruled out indicates, this star was a variable star located in that possibility because an explosion of that the constellation of Puppis. It was a fairly ordinary magnitude would likely destroy the envelope of the periodic variable, although with a rather complex donor star. Their evidence for this is the very same light curve, but still showing a distinct periodicity of structure Woudt noted in his paper (shown above). about fifteen and a half hours. It wasn't especially bright, yet something seemed to tug at my memory While the structure looks to be bipolar in nature, regarding the star's name as I scanned through other observations have suggested that there is an articles to write on. Just over a year ago, Nancy additional component along the line of sight and wrote a post on V445 Puppis stating it's a that the structure is more of a doughnut shape. In supernova just waiting to happen. A new article this case, the total amount of material lost is higher challenges this claim. than originally anticipated and must have come from from the envelope of the companion star. In December of 2000, V445 Puppis underwent an Additionally, observations in wavelengths able to unusual nova. It was first noticed on December pierce the dust have been unable to resolve a 30th, but archival records showed the eruption strong stellar source which suggests that the donor began in early November of that year and reached star's envelope has been largely blown away as a peak brightness on November 29th. The system well. Additionally, this large and rapid loss of mass was known to be a binary star system with a from the system may have broken the gravitational shared envelope in which the primary star was a bond between the two stars and allowed the giant white dwarf and thus, a nova was the most readily star to be ejected from the system, which would available explanation. also preclude the possibility of a supernova in the future. However, this wasn't a normal nova. Spectroscopic The conclusion is that V445 Puppis is not a 1 / 2 candidate for a supernova of any type in the future. It's own premature fireworks have likely destroyed whatever chance it may have had for an even grander show in the future. Provided by Universe Today APA citation: Will V445 puppis become a Ia supernova? (2010, December 6) retrieved 29 September 2021 from https://phys.org/news/2010-12-v445-puppis-ia-supernova.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. 2 / 2 Powered by TCPDF (www.tcpdf.org).