The James Webb Telescope sees the end of planet formation

Offering clues to the birth of our solar system Scientists using the James Webb Space Telescope (JWST) have captured a groundbreaking image: a nascent planetary system actively shedding its gas. This discovery allows us to take a new look at the process of formation of planets, including our solar system. DiscussThe © Ferra

It was previously known that planet-forming disks—the swirling clouds of dust and gas around young stars—contain significantly more gas than solid particles. The key question remained: when and how does this gas disappear? A new study led by Naman Bajaj of the University of Arizona sheds light on this mystery. By observing the young star T Cha, they were able to image for the first time the gas slowly leaving the system.

To do this, they were able to detect the signature of ionized neon—an atom of gas stripped of electrons—emitted by the escaping gas. The technique acts as a chemical fingerprint, revealing the origin of particles within the disk.

Further analysis suggests that the “cloud” is likely driven by high-energy light emanating from a young star. The team estimates that the loss of gas is equivalent to the annual loss of Earth's moon.

This new knowledge about the timing of gas dissipation could help scientists understand how much time planets have to form and grow. In addition, the rapid evolution observed in TCha's inner disk hints that we may witness complete depletion of gas and dust within our lifetime.