A massive star just vanished without a trace and astronomers don’t know why

disappearingstar

An artist’s impression of the star that vanised without a trace.


ESO/L. Calçada

Of all the things you’d expect to lose sight of, a star 100 times bigger than our sun probably isn’t top of mind. Yet scientists are stunned at the realisation that a massive star has somehow vanished into nothingness, with seemingly no explanation.

In a new study, published in the Monthly Notices of the Royal Astronomical Society on Tuesday, astronomers checked in on a gigantic star, nicknamed the Kinman Dwarf, in the galaxy PHL 293B, 75 million light-years from Earth. The team were interested in learning more about the low-metallicity environment of PHL 293B and had expected to see Kinman shining away.

But the star had vanished.

The star is no longer lighting up the galaxy. Indeed, it’s no longer lighting up anything at all as it’s simply… gone. Despite being seen most recently in 2011, when the team of scientists used the ESPRESSO instrument at Chile’s Very Large Telescope, they could not source the star. Using an additional instrument called the X-Shooter to ascertain where the star had gone, the team was unable to find it yet again.

Puzzlingly, however, there was also no evidence that the star had gone supernova, which could have accounted for its disappearance. As such, the question remains: What happened to the star?

There are two hypotheses: Either the star is still there but its light is much more dim and it’s obscured by a dusty cloud of debris, or the star “collapsed to a massive black hole without the production of a bright supernova.”

Either way, the implications for such an unexpected absence are far-reaching — especially when you consider whether this could occur more frequently. 

As the report states: “Given that the majority of such events in deep surveys will be much fainter than PHL 293B and located much farther, a detailed analysis of this object in the local Universe provides an important benchmark for understanding the late-time evolution of massive stars in low-metallicity environments and their remnants.”

The study’s lead author, Andrew Allan, told Vice that they plan to examine the Kinman Dwarf with the Hubble Space Telescope, in an attempt to find any evidence of the monster star’s demise.

“Just by comparing a before and after picture of the galaxy, we’d hopefully be able to pick out, first of all, the star itself, and then maybe what happened to the star and why it disappeared,” he said.

source: cnet.com