The star known as Betelgeuse has been dimming over the past month, which would suggest that it is likely to supernova. Stars supernova when they are at the end of their lives having run out of fuel after millions of years. When they do, they implode, collapsing in on themselves before a huge explosion occurs.
Over the past two weeks, Betelgeuse has gone from one of the top 10 brightest stars visible to the naked eye to the 21st – of roughly 5,000 which can be seen.
Edward Guinan, a professor in Villanova University’s Department of Astronomy and Astrophysics, and his team wrote in the Astronomers Telegram: “This appears to be the faintest the star has been measured since observations have been carried out of the star.
“We plan to continue to monitor the star. If the star continues to follow above periods, light minimum should occur soon.
“But this needs to be checked. This continues to be an opportune time to carry out complementary measures of Betelgeuse while it is in its current low state and is unusually cool and faint.”
Betelgeuse is a red giant, being around 12 times the size of the sun.
If it were placed in the solar system, it would consume everything as far as Jupiter.
However, the star is 643 light-years from Earth, meaning our planet will be safe from the explosion when it finally does supernova.
But Betelgeuse would still be visible from Earth when it does explode.
The last supernova which was visible to the naked eye came in 1604 when Kepler’s Star died, producing a bright enough light which was visible during the day time for three weeks.
When it finally dies, however, is a different matter.
Betelgeuse is so big that it has a relatively short lifespan, burning through all of its fuel in around 10 million years.
For reference, smaller stars like the sun will live for around 10 billion years.
Nonetheless, scientists are none the wiser as to when Betelgeuse will implode, stating it could happen within the next few years, up until 100,000 years away.
Astronomer Yvette Cendes of the Harvard-Smithsonian Center for Astrophysics said on Reddit: “We don’t think Betelgeuse is likely to go supernova in our lifetimes as it probably still has tens of thousands of years, if not 100,000.”
Other experts believe there could be another explanation for the star’s dimming.
Rutgers University physicist Matthew Buckley suggested an alien megastructure, or Dyson Sphere, could surround it.
A Dyson Sphere is a structure which surrounds a star which harnesses all of its energy to provide limitless energy for a civilisation.
Mr Buckley wrote on Twitter: “Weird how everyone is wondering if Betelgeuse dimming means it is going supernova (sadly, unlikely), but no one is asking the real question: is its dimming a sign that someone is finishing a Dyson sphere around it?”