Planets form from disks of gas and dust around young stars, but the gas needed for growth does not last forever. New observations from NASA's James Webb Space Telescope (JWST) now offer a new view of how this gas escapes and how the process changes as young planetary systems develop.

The research, led by Naman Bajaj from the University of Arizona and co-authored by SETI Institute scientist Uma Gorti, looked at 72 young, sun–like stars and their protoplanetary disks. This is one of the largest planet-formation studies using JWST. The findings show that different types of winds are more important at different stages in a planetary system's early life.

A race against time
"What is exciting about this study is that we can now see, across a large sample of young systems, how the mechanisms that remove gas from planet-forming disks change with time. Disk dispersal sets a fundamental clock for planet formation: once the gas is gone, the opportunity to build gas-rich planets is essentially over," said Gorti.

Today, our solar system is about 4.5 billion years old and is mostly empty space. In its first few million years, though, the sun was surrounded by a thick protoplanetary disk with about 100 times more gas than dust. Most of that gas eventually vanished.

Figuring out how and when this happens is important because the gas in these disks is the main ingredient for giant planets like Jupiter and Saturn. If the gas goes away too soon, these planets might not have enough time to build up their thick atmospheres.