Summary:
NASA’s Hubble and James Webb telescopes have provided a detailed look at Vega’s smooth debris disk, showing no major planets that would typically disturb the disk. This finding challenges existing theories about exoplanet systems, especially when compared to similar stars like Fomalhaut, which has a more complex, planet-affected disk. The new observations highlight variations in circumstellar disks, offering insights into planet formation and the unique structure of the Vega system.

In a detailed look at the star Vega, NASA’s Hubble and James Webb telescopes have revealed an unexpectedly smooth debris disk surrounding the star. This nearly 100-billion-mile-wide disk shows no clear evidence of large planets, which would usually create gaps or disturbances, leading astronomers to rethink assumptions about exoplanet systems.

The disk, observed by a University of Arizona team, consists of sand-sized particles swirling in the intense glow of Vega and smaller smoke-like particles reflecting starlight, distributed in layers by starlight pressure. Although a subtle gap exists at about 60 AU (double Neptune’s distance from our Sun), there are no planets large enough to affect the disk like those in our solar system.

The smoothness of Vega’s disk contrasts with the nearby star Fomalhaut, which has a more complex disk structure with multiple debris belts, likely influenced by unseen planets. This raises questions about why Fomalhaut may host planets while Vega does not, despite their similarities. Researchers hope these insights will deepen understanding of planet formation and the diversity of circumstellar disks.

Pioneering observations in 1984 first suggested that Vega had material for planet formation. The new Hubble and Webb observations provide unprecedented detail, revealing insights about Vega’s disk previously unknown, and advancing studies in planetary system diversity.

Two papers detailing these findings are available on arXiv and set for publication in *The Astrophysical Journal*.