The sudden dimming of the supergiant star Betelgeuse is thought to be caused by the release of a large amount of hot matter into space (Credit: NASA)

A few years ago, one of the brightest stars in the night sky began to dim.

At the time, astronomers thought it might indicate a supernova.

But Betelgeuse (pronounced “beetle”) has regained its shine and now joyfully lights up the universe.

So what is causing this?

New data from the Hubble Space Telescope suggests that an almighty explosion literally blew up the red giant star.

According to NASA, this gigantic explosion has never been seen in space before and dwarfs a similar explosion from the Sun.

Our parent star periodically expels part of its rarefied outer atmosphere, the corona, in a phenomenon called a coronal mass ejection (CME).

But the Betelgeuse explosion was about 400 billion times more powerful.

The ejected material cooled and formed dust clouds, temporarily obscuring the star as seen from Earth.

This unprecedented stellar contraction interrupted the monster star’s 400-day wobble cycle that astronomers have been measuring for more than 200 years.

This figure shows the change in brightness of the red supergiant Betelgeuse after its enormous mass has ejected most of its visible surface.

This image shows the change in brightness of the red supergiant Betelgeuse after its massive mass ejected much of its visible surface (Credit: NASA)

“We’ve never seen a massive flare on the surface of a star before,” said Andrea Dupré, of the Harvard-Smithsonian Center for Astrophysics in Massachusetts.

“We are left with something that we don’t fully understand. This is a completely new phenomenon that Hubble can directly observe and can resolve surface details.”

“We are observing the evolution of stars in real time.”

Monster Star is still slowly recovering from this devastating cataclysm.

“Betelgeuse is continuing to do some very unusual things right now. ‘The interior is a bit bright,'” Dupree explained.

Color composite showing the region around the red supergiant Betelgeuse, created from the Digital Sky Survey 2 exposure (Credit: Getty)

Hubble’s observations will help astronomers understand how red stars lose mass when their fusion reactors burn out.

NASA says the amount of mass loss has a significant impact on a star’s fate, but Betelgeuse’s surprisingly nasty behavior isn’t evidence that it will explode soon.

Therefore, the massive loss event that occurred in 2019 is not necessarily a sign of imminent detonation.