Astronomers: Senkaku IV was pierced by a mysterious force before it became dark

Every shining star in the universe will be extinguished one day, and its "lifespan" is closely related to its mass. For example, Proximal is about 12.2% of the Sun's mass, and its "lifetime" can be as high as trillions of years, while the Sun's "lifetime" is only about 10 billion years, and those stars are much larger than the Sun, its "lifetime" is even shorter.

For example, Betelgeuse, about 640 light-years away, has a mass of 16.5 to 19 times that of the Sun, which makes the star's "lifetime" much lower than that of the Sun, and although it was born 8 to 8.5 million years ago, it is already in its "late" age.

According to known stellar evolutionary patterns, massive stars like Sensuous IV do not die out silently in the universe, but after the "nuclear fuel" at their core is depleted, they undergo a powerful "supernova explosion" that releases enough energy in a short period to rival an entire galaxy. The energy released in a short period of time is comparable to that of an entire galaxy.

Observations show that the current Sensuous IV has evolved into a "red super giant", which can be up to 700 million times the size of the Sun, and this is also the last stage of the life cycle of Sensuous IV, which means that in the near future, this giant star is not too far from us will occur " This is the last stage of the life cycle of Sensuous IV, which means that shortly, this giant star, which is not too far away from us, will undergo a "supernova explosion".

The image above shows the observational record of Sensuous IV over the past 20 years (the horizontal axis represents the year, and the vertical axis represents the apparent magnitude), and you can see that the brightness of Sensuous IV has been changing since 1996, but usually within a small range, but between late 2019 and early 2022, the star experienced a steep dimming.

During this dimming, the brightness of Sensuous 4 was reduced to about two-thirds of its normal level, leading to speculation that Sensuous 4 was likely to blow up, but this did not happen, as it gradually returned to its normal brightness in the following time.

The anomalous performance of Sensuous IV has undoubtedly attracted a lot of attention, and astronomers have offered several explanations for this phenomenon in subsequent studies, with the most widely accepted one being that a huge dust cloud may have briefly obscured some of the star's light, giving us the illusion that the star had dimmed.

A new study suggests that the dimming of Sensual IV may not have been simply the result of a dust cloud, as it is suspected to have been pierced by a mysterious force before it dimmed.

The study was led by astronomer Lynn Matthews of the Massachusetts Institute of Technology and astronomer Andrea Duper of the Smithsonian Astrophysical Center at Harvard University.

In a paper to be published in the Astrophysical Journal, they show that, after careful analysis of detailed observations of Sensuous IV, the researchers found that the actual brightness of Sensuous IV during this darkening was about 20 percent fainter than previously announced and that its surface brightness distribution was more complex than the theoretical uniform elliptical disk, but did not have the distinctive feature of being obscured by a dust cloud.

The figure above shows the darkening process of Sensuous IV based on actual observations. The researchers found that during the darkening of Sensuous IV, the electron density in its southern hemisphere increased significantly, accompanied by signs of large material loss.

After linking the above phenomenon with the radio characteristics of Sensuous IV, the researchers made a bold speculation that Sensuous IV may have been pierced by a large-amplitude shock wave before it was dimmed, which led to a change in the density structure and surface temperature of Sensuous IV, and that the brightness of Sensuous IV would be steeply dimmed during the subsequent massive material loss. brightness gradually returns to normal again.

If this is the case, what mysterious force is responsible for such a powerful shock wave?

Astronomers do not have a definite answer to this question, and can only offer reasonable speculation that the shock wave came from the interior of Sensuous IV, which is usually not very stable at its core. Of course, this is just a guess, we can also guess that this is a mysterious force from deep space in the universe, but it would seem a little science fiction.

It is worth mentioning that, at a distance of 640 light-years, even if a "supernova explosion" occurred in Sensuous IV, the material generated by the shock wave is unlikely to affect the Earth, the only thing we need to pay attention to is whether the gamma-ray burst generated by the Sensuous IV burst will hit the Earth, fortunately, the direction of the gamma-ray burst is consistent with the rotation axis of the star Fortunately, the direction of the gamma-ray burst is consistent with the rotation axis of the star, and the rotation axis of Sensuous IV is not aligned with the Earth and is off by at least 20 degrees, so we do not have to worry about Sensuous IV posing a threat to the Earth in the future.

Reference.

L. D. Matthews & A. K. Duper, Spatially Resolved Observations of Betelgeuse at λ7 mm and λ1.3 cm Just Prior to the Great Dimming, arXiv:2206.04144v1 [ Astor-phisher] 8 Jun 2022.

Well, that's all we have for today, welcome to follow us and we'll see you next time.