A star 2.5 million times brighter than the sun has completely vanished

Greg Evans
Tuesday 30 June 2020 12:15

A gigantic star that is 2.5 million times brighter than the Sun has mysteriously disappeared without a trace.

The Kinman Dwarf galaxy is a staggering 75 million light-years away from earth and once housed a huge blue star that was significantly bigger than the one that lights our small part of the galaxy.

Astronomers began observing the star between 2001 and 2011 but a recent report published by the Monthy Notices of the Royal Astronomical Society shows that the star has completely vanished.

The star which is also known as 'Luminous blue variables', reportedly go supernova when they are near their death but there are no signs of this particular star having done that.

This had led the researchers to determine two possible scenarios for what has happened. Either the star has dimmed so much that it is no longer visible and is clouded by the dust from an earlier outburst or it has been completely sucked into a black hole and will never be seen from again.

In a statement released by the European Southern Observatory, Andrew Allan, a PhD student at Dublin's Trinity College and the lead researcher on the study said:

It would be highly unusual for such a massive star to disappear without producing a bright supernova explosion. 

Instead, we were surprised to find out that the star had disappeared. If true this would be the first direct detection of such a monster star ending its life in this manner.

The group began their research in 2019 but after using several different instruments found that they couldn't find the star at all despite looking in the location that it had been located before. Jose Groh, also of Trinity College added:

We may have detected one of the most massive stars of the local Universe going gently into the night. Our discovery would not have been made without using the powerful ESO 8-metre telescopes, their unique instrumentation, and the prompt access to those capabilities following the recent agreement of Ireland to join ESO.

The team in Ireland then collected their data with separate data from a team in Chile to try and determine what had happened. Andrea Mehner, a staff astronomer at ESO in Chile said:

The ESO Science Archive Facility enabled us to find and use data of the same object obtained in 2002 and 2009. The comparison of the 2002 high-resolution UVES spectra with our observations obtained in 2019 with ESO's newest high-resolution spectrograph ESPRESSO was especially revealing, from both an astronomical and an instrumentation point of view.

The older data showed that the outburst from the star most likely ended in 2011 with luminous blue variable said to lose their luminosity quickly after a mass spike.

However, the technology that is currently available to astronomers does not allow them to individually view stars in the Kinman galaxy meaning it could be sometime before they actually find out what has happened to the missing star. As IFL Science report, telescopes like the Extremely Large Telescope, which is currently being built in Chile will have that capability in future.