Produced by: Tarun Mishra
The James Webb Space Telescope (JWST) has captured a remarkably smooth, "pancake-like" disk of debris surrounding the star Vega, offering new insights into its cosmic environment. The images, published in early November, challenge previous expectations about how planetary systems form.
Vega, a bright blue star located 25 light-years from Earth, is about twice the size of our Sun. Despite being old enough to potentially host planets, the new images show no visible signs of exoplanets within its surrounding disk, leading researchers to question why this is the case.
The JWST's Mid-Infrared Instrument revealed the disk to be unusually uniform, with no noticeable gaps or structures that would indicate the presence of planets. This smoothness contrasts with other circumstellar disks that typically show clear signs of planet formation.
The study compared Vega’s disk to that of a similar star, Fomalhaut, which also has a large disk. Unlike Vega’s disk, Fomalhaut’s features a significant gap, suggesting the formation of exoplanets that have cleared the debris in that area.
Both JWST and Hubble Space Telescope images of Vega's disk show a dark band around 60 astronomical units from the star. However, this is not due to exoplanets, but rather the result of stellar radiation pushing smaller dust particles farther away from Vega.
The researchers have no clear explanation for why Vega’s disk appears so smooth compared to Fomalhaut's. They are puzzled by the fact that both stars should behave similarly under the same physical laws, yet only one shows signs of planet formation.
The discovery could suggest that certain conditions around stars, or even the nature of the stars themselves, might prevent planets from forming. This raises questions about the variety of exoplanet systems and how common alien worlds really are across the galaxy.
As the team continues to study Vega and other star systems, they hope to uncover whether more stars exhibit similar behavior to Vega. Understanding why some stars fail to form exoplanets could reshape our predictions about the frequency of habitable worlds beyond Earth.