The Mystery of Old Smoker Stars: A Stellar Discovery

Unveiling the Old Smoker Stars

Astronomers have recently made an intriguing discovery in the heart of the Milky Way galaxy. During a decade-long survey of the night sky, a new type of aging giant red star has been identified. These enigmatic stars, referred to as 'old smokers,' remain inactive for decades before emitting clouds of smoke and dust. This discovery has left astronomers fascinated, as it raises questions about the role of these stars in the distribution of elements across the universe.

This illustration shows an eruption occurring in the swirling disk of matter around a newborn star.

The mysterious old smoker stars were previously hidden from our view, and their unique behavior has captured the attention of the scientific community. Four studies detailing these observations were published in the Monthly Notices of the Royal Astronomical Society, shedding light on this intriguing stellar phenomenon.

Astronomers used an infrared telescope to spy a star that gradually brightened 40-fold over two years, and it has remained bright since 2015.

The observations of the old smoker stars were made possible through a decade-long survey that involved monitoring nearly a billion stars in infrared light. This allowed astronomers to pierce through the galaxys high concentrations of dust and uncover these otherwise hidden stellar objects. The survey was conducted using the Visible and Infrared Survey Telescope, situated at the Cerro Paranal Observatory in the Chilean Andes.

Infrared images show a red giant star, located 30,000 light years away near the center of the Milky Way. The star faded away and then reappeared over the course of several years.

The Search for Newborn Stars

Initially, the astronomers' goal was to search for newborn stars, which are notoriously difficult to detect in visible light due to obscuration by dust and gas in the Milky Way. However, the use of infrared light proved to be instrumental in uncovering these hidden or faint stellar objects. While the majority of the stars were easy to classify, a significant number posed a greater challenge. The team relied on the European Southern Observatorys Very Large Telescope to study individual stars, providing valuable insights into their behavior and characteristics.

During the survey, astronomers monitored hundreds of millions of stars and identified 222 that exhibited noticeable shifts in brightness. Further analysis revealed that 32 of these stars were newborn stars undergoing significant increases in brightness, some by as much as 300 times. These ongoing eruptions present an exciting opportunity for astronomers to study the evolution of these stars over time, offering valuable insights into the process of star formation and growth.

Dr. Zhen Guo, a lead author of the studies, highlighted the significance of these outbursts, describing them as occurring in the slowly spinning disc of matter that forms a new solar system. While these outbursts aid in the growth of the newborn stars, they also pose challenges for the formation of planets. The underlying reasons for the instability of these discs remain a subject of ongoing investigation, as astronomers strive to unravel the mysteries of star formation and planetary evolution.

The Unexpected Stellar Discovery

In the course of their observations of stars near the galactic center, the research team stumbled upon a surprising and perplexing phenomenon. They identified 21 red stars that exhibited unusual changes in luminosity, sparking curiosity among astronomers. The team's focused investigation revealed that these stellar objects were a new type of red giant stars, distinct from the traditional understanding of red giants.

These elderly red giant stars, located near the center of the Milky Way, behave in a manner previously unseen by astronomers. They remain dormant for extended periods, only to release clouds of smoke and dust in a completely unexpected fashion. The dim and red appearance of these stars, at times nearly invisible, presents a unique enigma that has captivated the scientific community.

The discovery of these old smoker stars challenges existing knowledge about the late stages of stellar evolution and the release of elements into space. Their presence in the innermost nuclear disc of the Milky Way holds significant implications for understanding the distribution of heavy elements across the universe. This unexpected stellar discovery has opened new avenues for research, prompting astronomers to delve deeper into the mysteries of these enigmatic red giant stars.