Betelgeuse — the 10 million-year-old star that around 900 times larger than the star of our solar system. Categorised as a red supergiant, stars like the Betelgeuse often burn bright, die soon, exploding in a beautiful supernova. And it looks like this one might be on the trajectory to go out with a bang.
ESO/M. Montargès et al.
Astronomers have been operating ESO’s Very Large Telescope and have discovered that since December, Betelgeuse was shining 64 percent less brightly than it usually does — something stars do when they’re at the end of their journey.
Betelgeuse has been the 11th brightest star in the sky — part of the Orion constellation. However today, it sits on the 24th position.
The observations were made using Spectro Polarimetric High Contrast Exoplanet Research (or SPHERE) instrument. This instrument allows researchers to see polarised IR light emitted by new planets that orbit around a star, but it also helped in capturing sharper images of Betelgeuse.
The most recent supernova to be seen in the Milky Way galaxy was SN 1604, which was observed October 9, 1604. Several people, including Johannes van Heeck, noted the sudden appearance of this star, but it was Johannes Kepler who became noted for his systematic study of the object.
Since the star isn’t very far from Earth — around 650 light-years away– they could capture images with a ton of detail that revealed ginormous blobs of hot gas that have migrated from the core of the star to the surface on the outside.
The images also revealed that the star is dynamic and is changing shape while also shining less brightly than usual.
Will the star really shutdown?
If Betelgeuse actually were to go supernova, it would be the brightest one in our galaxy that will outshine other stars near it. But the researchers feel there is still time for that.
One of the theories is that the red giant is going through a phase of pulsating, which is causing the heat to travel around its surface and dim the convection cells, causing the brightness to drop. Another theory is that it is just looking dim with the clouds of hot gas that it splurted out of itself.
According to Miguel Montargès, an astronomer at KU Leuven in Belgium and the leader of the team responsible for the new observations.“The two scenarios we are working on are a cooling of the surface due to exceptional stellar activity or dust ejection towards us. Of course, our knowledge of red supergiants remains incomplete, and this is still a work in progress, so a surprise can still happen.”