James Webb Space Telescope observes 72 stars and finds planet formation is a race against time
AI-summarised brief · reviewed before publication
Using JWST’s Mid‑Infrared Instrument, astronomers examined 72 young, Sun‑like stars to track how material leaves protoplanetary disks. By mapping molecular hydrogen loss they assembled a chronological “movie” of disk evolution, revealing that mass‑removal mechanisms shift as stars age. Early disks lose gas primarily through magnetically driven jets and winds, while later stages are dominated by photoevaporation caused by high‑energy stellar radiation. The study shows that gas giants such as Jupiter must acquire their massive atmospheres before these dispersal processes strip the disk, whereas smaller rocky planets have a longer formation window. The findings constitute the most comprehensive survey of disk‑mass loss to date and provide a framework for predicting where and when different planet types can form around Sun‑like stars.
💡 Why It Matters
- · By pinpointing the timing of gas‑disk dispersal, the research narrows the window for giant‑planet birth, offering a concrete test for models of our own Solar System’s origins.
