https://newatlas.com/vanishing-star-skip-supernova-black-hole/49725/

Birth of a black hole witnessed as star vanishes without a bang:

For the first time, astronomers have witnessed a star disappear right before their eyes. Known as N6946-BH1, the star appears to have collapsed into a black hole without the usual flair of a supernova, which not only marks the first time scientists have witnessed the birth of a black hole, but could change our understanding of the life and death of stars.

According to conventional thinking, when a star exhausts its energy supply, it violently ejects most of its matter outwards in a supernova, before collapsing in on itself to form a black hole. But N6946-BH1 has bucked the trend, skipping the supernova stage and quietly collapsing into a black hole. These failed supernovae (or "massive fails", as the team calls them) could help patch some holes in our stellar knowledge.

"The typical view is that a star can form a black hole only after it goes supernova," says Christopher Kochanek, lead researcher on the study. "If a star can fall short of a supernova and still make a black hole, that would help to explain why we don't see supernovae from the most massive stars.

more at link.....

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the paper:

https://academic.oup.com/mnras/article/468/4/4968/3098190

The search for failed supernovae with the Large Binocular Telescope: confirmation of a disappearing star:

 

Abstract

We present Hubble Space Telescope imaging confirming the optical disappearance of the failed supernova (SN) candidate identified by Gerke, Kochanek & Stanek. This ∼25 M⊙ red supergiant experienced a weak ∼106 L⊙ optical outburst in 2009 and is now at least 5 mag fainter than the progenitor in the optical. The mid-IR flux has slowly decreased to the lowest levels since the first measurements in 2004. There is faint (2000–3000 L⊙) near-IR emission likely associated with the source. We find the late-time evolution of the source to be inconsistent with obscuration from an ejected, dusty shell. Models of the spectral energy distribution indicate that the remaining bolometric luminosity is >6 times fainter than that of the progenitor and is decreasing as ∼t−4/3. We conclude that the transient is unlikely to be an SN impostor or stellar merger. The event is consistent with the ejection of the envelope of a red supergiant in a failed SN and the late-time emission could be powered by fallback accretion on to a newly formed black hole. Future IR and X-ray observations are needed to confirm this interpretation of the fate for the star.

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Does this bring into question the science of Supernovas? Could extra massive stars actually form a BH at their cores first, without any "rebound" and instead just consume the rest of the inflated star?

Edited June 2, 20187 yr by beecee

Thank you beecee for taking time to post new cool articles. Always choosing interesting/relevant articles.

MVP of the news section.  

Cool happenings, with that observation thanks for sharing Beecee