Star that emits smoke is discovered in the Milky Way – 01/26/2024 – Science

A new type of star, which remains silent for long periods of time before exhaling a cloud of smoke, has just been detected by scientists.

Nicknamed “old smokers”, this type of newly discovered star is located in the heart of the Milky Way, according to a study published this Friday (26) in the monthly bulletin of the Royal Astronomical Society.

They are red giants, stars that at the end of their lives acquire this size and a low surface temperature.

Due to their pale, reddish color, “sometimes it is not possible to see them”, explains Dante Minniti, from Andrés Bello University.

The team of scientists behind this discovery were looking for stars at the end of their lives. Over ten years of research, hundreds of millions of stars were analyzed using the Vista telescope, located in Chile.

The search was for newborn stars, called protostars, which are prone to frequent and exuberant eruptions.

The investigation detected 32 protostars, “the largest number found so far in just one group,” said astrophysicist Philip Lucas, professor at the University of Hertfordshire in the United Kingdom and lead author of a new study.

However, in the background, they found this “pleasant surprise”, an exhalation that had not been detected until now, he adds.

‘We don’t fully understand’

The “smoking old ladies” were situated near the center of the Milky Way, a densely populated, metal-rich region called the Nuclear Stellar Disc.

“The surprising thing about this new discovery is that we are seeing stars that were just sitting there doing nothing,” Lucas said.

Subsequently, these stars abruptly became between 40 and 100 times fainter, sometimes so thin that the telescope’s infrared vision could barely detect them.

A few years later, apparently without warning, they returned to their former brilliance.

“Everything we’ve been able to find out about them suggests that they are stars giving off smoke, for reasons we don’t fully understand,” the astrophysicist added.

These smoke clouds are believed to temporarily obscure the stars from our view.

According to Lucas, there are many other “heavy elements” — anything heavier than hydrogen and helium — in this region of the galaxy, which could create more dust in the star’s atmosphere.

The components of this dust remain a mystery, however, if this theory is correct, then the amount of matter ejected by these stars could play a significant role in how heavy elements are dispersed throughout our galaxy and beyond, he said. Lucas, emphasizing that these were just initial guesses.

“We are researching to see what makes the most sense,” he said.

Researchers have found at least 21 “old smokers,” but they suspect there are many more.