A new study is changing the way scientists think about how young stars and planets form.
Led by Professor Paolo Padoan from the Institute of Cosmos Sciences at the University of Barcelona, the research shows that the environment around a newborn star plays a much bigger role than previously believed.
When a star forms, it is usually surrounded by a spinning disk of gas and dust.
Over time, this disk is where planets are born. For many years, scientists thought these disks just gradually shrank as material was pulled into the star and used to form planets.
But Professor Padoan’s study, published in Nature Astronomy, reveals that the opposite can happen—the disks can actually grow larger and live longer thanks to the surrounding gas cloud.
The key is a process called Bondi-Hoyle accretion. As young stars stay in their birth clouds for millions of years, their gravity can pull in more material from the gas cloud around them.
This extra material doesn’t make the star itself much bigger, but it can add to the disk, making it larger and giving it more material to form planets.
Padoan explains that understanding how much gas a star can attract—and how it affects the disk’s size and spin—requires careful modeling of the chaotic motions in space, known as turbulence.
His team used powerful computer simulations combined with real observations from ALMA, the world’s most advanced radio telescope, to show how this process works. Their findings help explain why many protoplanetary disks are larger than previous models had predicted.
Researcher Veli-Matti Pelkonen, a member of the team, says that simulations allow scientists not only to match observations but also to see the hidden structures of gas and magnetic fields and how they change over time.
With more powerful supercomputers and better telescopes like ALMA and the James Webb Space Telescope, researchers will be able to explore these processes in even greater detail in the future.
This discovery is not just about understanding star formation. It also gives new insights into how planets—and possibly even habitable worlds—might form. By learning more about how disks grow and survive, scientists could better understand where and how life-friendly planets might appear across the galaxy.
