M31-2014-DS1, slow disappearance of a massive star

[Astronuc]

I heard a report of an unusual disappearance of a massive star in the Andromeda (M31) galaxy.
M31-2014-DS1 was a supergiant

How it was reported in "Have astronomers witnessed the birth of a black hole?"
https://www.npr.org/2026/02/12/nx-s1-5707552/have-astronomers-witnessed-the-birth-of-a-black-hole

Science Report - Disappearance of a massive star in the Andromeda Galaxy due to formation of a black hole
https://www.science.org/doi/10.1126/science.adt4853

Editor's Summary - In a dying massive star, the core collapses to form a compact object. Simultaneously, the outer layers can be ejected at high speed, which is observed as a supernova. Theory predicts that sometimes the ejection speed is too low to escape the gravitational field, so the outer layers fall back over several years, producing no supernova and a more massive compact object. De et al. have identified a supergiant star in the nearby Andromeda Galaxy that brightened in the infrared then decreased in optical brightness over the next few years until it became undetectable. They attribute this behavior to a failed supernova and the formation of a black hole. —Keith T. Smith

The disappearance of a massive star marking the birth of a black hole in M31​

https://arxiv.org/abs/2410.14778

Caught in the Act: Astronomers Watch a Vanishing Star Turn Into a Black Hole​

https://www.simonsfoundation.org/20...atch-a-vanishing-star-turn-into-a-black-hole/

The Quiet Formation of a Black Hole​

https://www.caltech.edu/about/news/the-quiet-formation-of-a-black-hole

Scientists Capture the Clearest View Yet of a Star Collapsing Into a Black Hole​

https://news.columbia.edu/news/scientists-capture-clearest-view-yet-star-collapsing-black-hole

Astronomers Find Compelling Evidence of a Star Collapsing Directly Into a Black Hole​

https://keckobservatory.org/astrono...a-star-collapsing-directly-into-a-black-hole/

The fate of the failed supernova candidate M31-2014-DS1​

https://academic.oup.com/mnras/article/546/3/stag052/8424233

The fate of massive stars above 20‌  remains uncertain. Debate persists about whether they die as supernovae (SNe), or if they collapse directly into black holes (BHs) with little or no optical outburst – so-called failed supernovae. The source M31-2014-DS1 experienced an optical outburst in 2014 and has remained faint at visual wavelengths since then. Due to its persistent faintness, it has been proposed as a failed SN candidate. We present new observations of this candidate obtained using the James Webb Space Telescope (JWST), the Submillimeter Array, and Chandra. The JWST observations demonstrate that a luminous mid-infrared source persists at the same location a decade after the star faded at visual wavelengths. We model its current spectral energy distribution as a dust-enshrouded star. No X-ray emission is detected, disfavouring the hypothesis that the late-time luminosity is powered by accretion on to a BH. We find that the remaining source is highly obscured by an asymmetric distribution of circumstellar dust, making it difficult to quantify its physical properties using spherically symmetric radiative transfer codes. The dust geometry requires that the inferred bolometric luminosity is only a lower limit, as a significant fraction of the central source’s radiation may escape without being reprocessed by dust. We discuss the implications of these findings in the context of failed SN models and consider the potential overlap with signatures expected from a stellar merger, which also seems to provide a plausible explanation of this source.

Star's disappearance in Andromeda marks the birth of a black hole​

https://phys.org/news/2024-11-star-andromeda-birth-black-hole.html#google_vignette


Proposal to observe the supergiant M31-2014-DS1
https://www.stsci.edu/jwst/phase2-public/6809.pdf