A star shining 2.5 million times the sun has disappeared from the night sky. The star may have collapsed into a black hole without first triggering a supernova. This is a rare event even in dying stars. The disarrayed star is located in or once located in the Kinman dwarf galaxy in Aquarius, about 75 million light-years from Earth. At such a distance, it is impossible to see a single star clearly. However, real mass stars will be so bright that they leave evidence in the form of light signals telling astronomers they are there.
By our sun’s standards, the glowing blue variable stars are huge and flicker ingress ingress. However, while they are spectacular, they are also unstable and prone to violent eruptions, during which they lose mass at breakneck speed. In 2001-2011, astronomers observed the star in the hope of deepening our understanding of the life cycle of the monster star and its ultimate fate. In 2019, a team of international scientists will try to continue the work by observing the variable star with a more powerful ESO Very Large Telescope (VLT). To their surprise, the star’s light signal has disappeared.
It is unusual for the star to appear to disappear suddenly, because, according to researchers, such a giant star is expected to explode in supernova after its life cycle is over. Since their own observations found no evidence of the star, the researchers turned to old data captured by two powerful spectrometers installed on the VLT Four telescopes in 2002 and 2009.
These archived data suggest that the star may have experienced a powerful eruption that caused the star to lose a lot of mass and end sometime after 2011. Based on their analysis, the team identified two potential causes of star disappearance, as well as the absence of visible supernovae. By the end of the event, the glowing blue variable star may have transitioned to a less glowing star, shrouded in a thick field of dust made up of previously dropped material.
The second explanation suggested by the team is even more dramatic: the star could end its star life by quietly collapsing into a giant black hole. If the latter is true, it will be the first time such a huge, extremely bright star has been found to have ended its life in this way.
However, the researchers did not rule out the possibility that the star had a supernova during an unobserved period from 1995 to 1998. In this case, astronomers believe that the star they saw between 2001 and 2011 should be characterized by interactions between supernova ejections and dense ring-star media.
In the future, astronomers will be able to use the European Southern Observatory’s upcoming very large telescope to conduct more detailed studies of individual stars hidden in distant dwarf galaxies like Kingman, which is expected to be completed by 2025. The paper has been published in the Monthly Issue of the Royal Astronomical Society.