Thanks to its extraordinary sensitivity and resolution, Webb just solved a mystery more than two decades old. In 2003, the Hubble Space Telescope saw evidence of a massive planet around an ancient star. This puzzled astronomers, who knew that such stars in the early universe lacked a lot of the heavier elements considered essential for building planets. Current models predict that the disks around this type of star have short lifetimes, so short that planets cannot grow large, or maybe even form at all. Yet, there it was!

Astronomers then turned to a nearby proxy for the early universe – the star-forming region NGC 346. There, Hubble saw signs that planet-forming disks existed around stars 20 to 30 million years old, much older than theories predicted such disks could survive.

The Hubble findings were intriguing, but without a way to obtain spectra, scientists could not be sure they were witnessing genuine accretion and the presence of disks. Now, using Webb, researchers have confirmed the presence of planet-forming disks in NGC 346, and discovered that these disks are long-lived. The finding affirms the Hubble result, and it is causing scientists to rethink current models of planet formation.