Rare event: Dying red giant star Betelgeuse disappears for a few seconds next Tuesday

On December 12, the famous star Betelgeuse will be briefly hidden from view as it passes behind the asteroid 319 Leona.

The red supergiant Betelgeuse is located about 530 light-years away from Earth. This enormous star is easily visible with the naked eye on clear evenings and clearly distinguishes itself from the other stars with its red color. But Betelgeuse will not be seen for a while on December 12, when it disappears behind asteroid 319 Leona in a rare event.

The moment has arrived
“We have been waiting for years and now the moment has finally come,” it said Virtual Telescope Project in a statement. “On December 12, 2023, the asteroid 319 Leona will briefly pass between us and the star Betelgeuse, eclipsing it. Of course Betelgeuse is a great distance away; this alignment is purely a matter of perspective. But nevertheless, the result will be absolutely stunning.”

Occultacy
During the occultation, Betelgeuse will disappear for a short period of time. Astronomers don’t know exactly how long. That depends on the angular size between this enormous star and the asteroid – and this data is not exactly known. However, experts suspect that Betelgeuse will only be hidden from our view for a few seconds. In addition, the position of the observer on Earth is important, which means that this special event will only be visible from a very narrow strip of our planet.

Preview
The occultation actually gives a foretaste of what awaits us in the distant future. During that moment, we will catch a glimpse of the night sky as it will look when Betelgeuse explodes as a supernova and then disappears into darkness (see box). Exactly when Betelgeuse will explode remains uncertain. In astronomical terms, this is generally expected to happen in the near future, sometime in the next 100,000 years. Fortunately, the distance to Earth is large enough that we will not be directly affected by the supernova explosion. Nevertheless, future generations on Earth can witness a spectacular fireworks show!

More about Betelgeuse
If there is one star that has been attracting attention for quite some time, it is the red giant star Betelgeuse. With an age of about 8 million years, the star is very young (for comparison: our sun has been around for about 4.5 billion years). Despite its youth, the star is about to die and unleash a spectacular event: a gigantic explosion, better known as a supernova. At the end of 2019, astronomers believed that the long-awaited moment had arrived. The brightness of the red supergiant began to dim. This striking decrease in brightness, noticeable even to the naked eye, caused excitement and speculation. The question arose: could the star be about to explode? Unfortunately, that turned out not to be the case. Betelgeuse is now back to its usual brilliance; as of April 2020, the star shone as brightly as before the notable decrease in brightness. Although the star has recovered, astronomers are of course still keeping a close eye on Betelgeuse.

But the occultation will most likely provide other valuable information as well. “Such occultations are particularly useful in revealing the shape of the asteroid involved,” says astrophysicist Gianluca Masi, director of the Virtual Telescope Project. “In this case, we even hope to explore the surface of Betelgeuse. As 319 Leona passes in front of it as seen from Earth, we hope to gain more insight into the large convective cells on the surface of this red supergiant that are responsible for its variable brightness.”

Southern Italy
Astronomers of the Virtual Telescope Project will travel to southern Italy, one of the locations on earth where the occultation will be clearly visible. Not only will they be able to admire the rare event from this spot, but they will also strive to collect valuable scientific data.

Would you also like to watch? It Virtual Telescope Project will start a live broadcast. The broadcast is scheduled for December 12, 2023, starting at 2:00 AM Dutch time.