Betelgeuse started dimming abruptly last winter, and some astronomers even proposed that the star might be going supernova.
Betelgeuse, a massive star, the tenth-brightest star in the night sky and, after Rigel, the second-brightest in the constellation of Orion, is probably not going to explode anytime soon.
Although astronomers have spotted the star dimming abruptly last year hinting at a possibility of it going supernova, a new study suggests that the star will shine on, at least in the near future.
The culprit of the anomalous dimming was likely a cloud of dust surrounding the star, causing it to dim from our vantage point.
New observations from the Hubble Space Telescope suggest that the unexpected dimming of the supergiant was likely caused by an immense amount of hot material ejected into space, forming a dust cloud that blocks starlight from Betelgeuse’s surface.
Betelgeuse is an aging red supergiant star that has increased in size as a result of changes in nuclear fusion processes at its core.
The star is so large that if it were to replace the Sun in the center of the Solar System, its outer surface would extend beyond the orbit of Jupiter.
The unprecedented phenomenon of Betelgeuse’s great dimming, which can be perceived even with the naked eye, began in October 2019. By mid-February 2020, the brightness of reduced notably.
This sudden dimming has puzzled astronomers, who have tried to explain what was going on with Betelgeuse.
Now, thanks to new Hubble observations, a team of researchers proposed that a dust cloud formed when superhot plasma was released on the star’s surface and passed through the hot atmosphere to the outer layers, where it cooled and generated dust caused the star to shine less bright than what we are used to seeing.
“With Hubble, we see the material as it left the star’s visible surface and moved out through the atmosphere before the dust formed that caused the star to appear to dim,” revealed lead researcher Andrea Dupree, associate director of The Center for Astrophysics | Harvard & Smithsonian.
“We could see the effect of a dense, hot region in the southeast part of the star moving outward.”
The resulting cloud blocked light from about a quarter of the star’s surface, a phenomenon that began in late 2019. By April 2020, the star returned to its normal brightness.
Betelgeuse’s life will end in a supernova explosion, and some astronomers think the sudden dimming may be a pre-supernova event.
The star is relatively close, about 725 light-years away. What we see now is actually a glimpse into the past. Because of its distance, what astronomers have observed in 2019 is something that actually took place in the year 1,300 AD, but the light of the event is barely reaching Earth now.
The team at the Harvard-Smithsonian Center for Astrophysics will have another chance to observe the star with Hubble in late August or early September.
At the moment, Betelgeuse is in the daytime sky, too close to the Sun for telescope observations.