Amazing stuff! Apparently, this star has been observed again and again since 2003.
"... “For the first time, we have succeeded in taking a zoomed-in image of a dying star in a galaxy outside our own Milky Way,” ...
The star, WOH G64, is in the Large Magellanic Cloud – a small galaxy that orbits the Milky Way – about 160,000 light-years from Earth. WOH G64 is a red supergiant about 2,000 times larger than our Sun.
The Large Magellanic Cloud has also recently provided the first evidence of a planet-forming disc around a star in another galaxy. ..."
"... While astronomers have taken about two dozen zoomed-in images of stars in our galaxy, unveiling their properties, countless other stars dwell within other galaxies, so far away that observing even one of them in detail has been extremely challenging. Up until now. ...
The team thinks that these shed materials may also be responsible for the dimming and for the unexpected shape of the dust cocoon around the star. The new image shows that the cocoon is stretched-out, which surprised scientists, who expected a different shape based on previous observations and computer models. The team believes that the cocoon’s egg-like shape could be explained by either the star’s shedding or by the influence of a yet-undiscovered companion star. ..."
From the abstract:
"Context. Significant mass loss in the red supergiant (RSG) phase has great influence on the evolution of massive stars and their final fate as supernovae.
Aims. We present near-infrared interferometric imaging of the circumstellar environment of the dust-enshrouded RSG WOH G64 in the Large Magellanic Cloud.
Methods. WOH G64 was observed with the GRAVITY instrument at ESO’s Very Large Telescope Interferometer (VLTI) at 2.0–2.45 μm. We succeeded in imaging the innermost circumstellar environment of WOH G64 – the first interferometric imaging of an RSG outside the Milky Way.
Results. The reconstructed image reveals elongated compact emission with a semimajor and semiminor axis of ∼2 and ∼1.5 mas (∼13 and 9 R⋆), respectively. The GRAVITY data show that the stellar flux contribution at 2.2 μm at the time of our observations in 2020 is much lower than predicted by the optically and geometrically thick dust torus model based on the VLTI/MIDI data taken in 2005 and 2007. We found a significant change in the near-infrared spectrum of WOH G64: while the (spectro)photometric data taken at 1–2.5 μm before 2003 show the spectrum of the central RSG with H2O absorption, the spectra and JHK′ photometric data taken after 2016 are characterized by a monotonically rising continuum with very weak signatures of H2O. This spectral change likely took place between December 2009 and 2016. On the other hand, the mid-infrared spectrum obtained in 2022 with VLT/VISIR agrees well with the spectra obtained before 2007.
Conclusions. The compact emission imaged with GRAVITY and the near-infrared spectral change suggest the formation of hot new dust close to the star, which gives rise to the monotonically rising near-infrared continuum and the high obscuration of the central star. The elongation of the emission may be due to the presence of a bipolar outflow or effects of an unseen companion."
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