Scientists recently observed a star that seems to have disappeared. Using the European Southern Observatory's Very Large Telescope (VLT), researchers have found that an unstable, massive star in a dwarf galaxy 75 million light-years away has vanished without a trace.
Various team of astronomers between 2001 and 2011 studied the mysterious massive star, located in the Kinman Dwarf galaxy. They noticed that the star was in the late stages of its lifespan.
They wanted to find out how very massive stars end their lives, and the object in the Kinman Dwarf seemed like the perfect target. However, things took an interesting turn when they pointed ESO's VLT to the distant galaxy in 2019. To their surprise, the astronomers discovered that the star had vanished.
The study of the star was led by PhD student Andrew Allan of Trinity College Dublin, Ireland, and it was published in Monthly Notices of the Royal Astronomical Society.
According to the researchers, the star might have disappeared after becoming less bright and being partially obscured by dust. They also said that it might have collapsed into a black hole without producing a supernova.
"If true, this would be the first direct detection of such a monster star ending its life in this manner," said Allan.
The Kinman Dwarf galaxy is located some 75 million light-years away in the constellation of Aquarius, making it too far way for astronomers to see its individual stars, but they can detect the signatures of some of them, reported Science Daily.
During their observations of the galaxy between 2001 to 2011, scientists observed the light coming from the galaxy that showed evidence that it hosted a 'luminous blue variable' star some 2.5 million times brighter than the Sun.
The study reports that stars of this type are unstable, showing occasional dramatic shifts in their spectra and brightness. Even so, luminous blue variables leave specific traces scientists can identify. But, such traces were absent from the data they collected in 2019.
"It would be highly unusual for such a massive star to disappear without producing a bright supernova explosion," says Allan.
The researchers will get a closer look at the star's fate once the ESO's Extremely Large Telescope (ELT) comes into operation in 2025. The ELT can capture images at high resolution, including very distant stars such as those in Kinman Dwarf, located more than 75 million light-years away.