Betelgeuse: Riddles about mysterious processes on the giant star solved

Betelgeuse: Riddles about mysterious processes on the giant star solved
Written by insideindyhomes

Betelgeuse is one of the most exciting stars in our galaxy. Visible to the naked eye as a bright red dot from Earth, it is a giant star about twenty times the mass and about eight hundred times the diameter of our Sun.

A few years ago, Betelgeuse astounded the astronomy world: the super-bright celestial body suddenly lost its luminosity, giving rise to numerous speculations. But now researchers from Tokyo have literally brought light into the dark.

Giant star Betelgeuse: Darkening mystery solved

Betelgeuse belongs to the constellation Orion and is the second brightest star in this constellation. As a red giant, it has a much shorter lifespan than our sun. It lives only a few million years and eventually ends up as a supernova. This is an explosion that massive stars like Betelgeuse undergo at the end of their lifetime. The star itself flashes extremely brightly for a short time, releasing an enormous amount of energy.

In 2019 and 2020, Betelgeuse attracted a lot of attention because the star that was actually so bright suddenly darkened significantly. In February 2020, it was only 35 percent of its usual luminosity. It was quickly assumed that it would now become a supernova. Even if this rumor was soon dispelled and the experts agreed that the sudden darkening of Betelgeuse was no indication of an imminent explosion – the mystery of this celestial phenomenon could not be solved.

But that has now changed: Researchers from the University of Tokyo have now evaluated data that provides an explanation for the red giant’s darkening – quite incidentally. Actually, their weather satellite called “Himawari-8” had the earth in view for years. Coincidentally, he also kept observing Betelgeuse, which is actually quite far away. For 4.5 years, they collected optical and infrared light data about Betelgeuse every 1.7 days. The period during which the star visibly dimmed was also recorded.

Dust and lower surface temperatures caused Betelgeuse to lose some of its luminosity

The researchers published the analysis of the data in the journal “Nature Astronomy”. According to them, the loss of brightness was triggered by a combination of two phenomena: On the one hand, the surface temperature of the star fell by around 140 degrees Celsius, and on the other hand, dust from the warm gas in the vicinity of the star condensed. The dust intensified the blackout caused by the drop in temperature.

In 2021, researchers from Belgium had already put forward a similar thesis. The data analysis from Tokyo thus confirms the results – the mystery of the darkening of the red giant seems to have finally been solved.

Today Betelgeuse has returned to its usual brightness. The topic of supernova is by no means off the table. The giant star could still explode at any moment – and in all likelihood it would not go unnoticed on Earth either.

For further reading: First image of the black hole at the center of the Milky Way

#Betelgeuse #Riddles #mysterious #processes #giant #star #solved

About the author


Leave a Comment