A new analysis of the photometric variations of Orion's red giant star, Betelgeuze, suggests that the giant star has a hitherto unknown companion star, revealing new findings by researchers at the HUN-REN Research Center for Astronomy and Earth Sciences (CSFK) and their US team. peers.
The brightness and dimming of Betelgeuse's star has excited astronomers for years, many of whom are convinced it could be a harbinger of an imminent supernova explosion. However, the tenth brightest star in the night sky may not yet be on the verge of going supernova. That's what a new study claims, which concluded from examining the star's optical changes that they are likely caused by another, as yet unknown, star orbiting it – they wrote in the HUN-REN CSFK announcement on Monday.
“The betel buddy,” as Jared Goldberg, the lead author of the scientific article, called it, in the English original) acts like a kind of snow shovel: it cleans the interstellar dust produced by the giant star, blocking its light, around it. That's why “We see Betelgeuse periodically getting brighter and then dimming again as its companion moves.”
“We have ruled out any other processes associated with Betelgeuse that we might think are responsible for the observed brightness and dimming,” Jared Goldberg, a researcher at the Center for Computational Astrophysics at the Flatiron Institute in New York, was quoted as saying. What he said in the statement.
He added: “The only hypothesis that fits the data is that Betelgeuse is not alone.”
The work of Jared Goldberg and colleagues has been accepted for publication by The Astrophysical Journal. In addition to Goldberg, the other authors of the article are Meredith Joyce, a professor at the University of Wyoming, who was a Marie Curie Fellow at the Institute of Astronomy at HUN-REN CSFK until the summer of 2024, and Laszlo Molnar, a senior scientific fellow at HUN-REN CSFK.
Betelgeuse is a giant red supergiant star: 100,000 times brighter and 400 million times more massive than the Sun. The star is approaching the end of its short life, and when it explodes as a supernova, it will become so bright that it will be visible in the daytime sky for weeks. By measuring the “pulse” of a star, astronomers can estimate when, in terms of magnitude, an explosion can be expected. They explained that Betelgeuse is a variable star, meaning that it periodically shines and then fades, with two types of pulses: one of which is a little longer than a year, and the other with a duration of about six years.
According to some astronomers, the longer change represents the “fundamental mode” of the star, that is, the change by which the star as a whole expands and contracts: in this case, and based on models, it could explode within a few hundred or thousands of years. Meanwhile, if a shorter period was the basic situation, the star could live for another hundred thousand years.
In this case, the six-year cycle must be the so-called long secondary period, which is created by an external cause. Astronomers don't yet have a clear explanation for the long secondary periods of red giants, but a leading hypothesis is that the companion star deflects dust clouds produced by the giant star, changing the amount of light that reaches Earth from it.
The three researchers looked at other processes that could be considered to explain long subperiods, from the flow of stellar material up and down to the star's magnetic field. However, after scrutinizing observational data and the latest stellar modeling results, they concluded that the presence of betel sibling (formally known as alpha Orionis B) is by far the most likely explanation.
Researchers have not yet been able to clearly determine what type of celestial body the betel nut might be. “It's difficult to say what it might actually be, other than estimating its mass and trajectory. A sun-like star is the most likely candidate, but it's not the only one,” Meredith Joyce explains.
“A more exotic hypothesis, and my personal favourite, although my co-authors don't necessarily agree with it, is that the companion is a neutron star: the core of a star that previously exploded as a supernova. Then we should see its X-rays,” the researcher added. “So far, no one has seen that, but we have to take a closer look.”
Researchers' current plan is to capture the companion, which will be best observed around December 6 of this year.
“Betelgeuse has been the target of many researches and articles since the advent of astrophysics. However, we have the opportunity to make important discoveries even today: this time in the form of a star similar to the Sun, which has been in front of our noses until now, hidden only by the light of the amazing giant,” Molnar summarized. The importance of discovery.
Latest news in science