The Very Large Telescope (VLT) observed a very large star about 75 million light-years away, a PHL 293B galaxy called Kinman Dwarf, which astronomers studied especially between 2001 and 2011, as it turned out to be probably in the final stages of their lives. But now she is gone and the question is whether she was only covered by some other object, such as a cloud of dust, or she really disappeared, or changed into a form in which it is no longer shown to us. But that would mean that the star had jumped over the supernova phase and probably collapsed straight into a black hole, the first ever astronomers had discovered.
Doctoral student Andrew Allan from Trinity College Dublin and his colleagues wanted to look at the star last year to find out more about how big stars end their lives, but after the VLT focused on Kinman Dwarf, it was found that this star is simply gone.
Even between 2001 and 2011, the star could boast extremely high luminosity, in multiples of 2.5 million Suns. Similar stars appear to be highly unstable and show dramatic changes in spectrum and brightness. However, from the point of view of astronomers, this is definitely not usual for them to disappear without a trace and, above all, without a final supernova explosion.
The team of astronomers tried to find the star at the earliest in August 2019 using the ESPRESSO instrument at the VLT, and later they tested the X-shooter on the same telescopes and again they were not successful. However, old data indicate that the star may have been very active during the years 2001 to 2011, which represented a sharp increase in brightness in a very short period and it is possible that now this star has only “calmed down” and because of this is no longer so visible nor can the specific traces of the blue variable giant to which it belonged be recorded. That’s one possibility, and the other is that the star really collapsed into a black hole without the usual supernova interstage.
We will probably wait many more years for the answer and it could be provided by the upcoming ESO Extremely Large Telescope (ELT), which could be able to recognize individual stars even in such distant galaxies as Kinman Dwarf.