Astronomers from the European Southern Observatory (ESO) face a mystery. They are a heavy star, "lost" deep in the universe. The star may have collapsed into a black hole without a supernova. That would be unique for science, reports the ESO on Tuesday.

The star was last seen some 75 million light-years away from Earth in the Kinman dwarf galaxy in the constellation Aquarius. The star was light blue and very bright, about 2.5 million times brighter than the Sun.

Observations between 2001 and 2011 showed that the star was in its final stage. When stars die, it happens with a massive explosion called a supernova. In some cases, a black hole is created after that.

When astronomers once again aimed the Very Large Telescope (VLT), the world's most advanced optical instrument, at the Kinman dwarf galaxy in 2019, the star suddenly disappeared without a trace. Other attempts, including using other instruments, were also unsuccessful.

Star would scoff at science

If it is true that the star has fallen into a black hole without a supernova, it would be a unique event, according to the astronomers. The star would mock with current scientific insights.

Another explanation by the astronomers for the disappearance is a lot less exciting. This is because the star has suddenly become a lot less bright and has also become eclipsed by dust.

According to the astronomers, further research is needed to determine what fate the star has suffered. Scientists may be able to solve the cosmic mystery with ESO's new telescope, the Extremely Large Telescope (ELT), which will come on stream in 2025 and can look even deeper into the universe.