
Outflows of gas from protoplanetary disks influencing star and planet formation.Protoplanetary disk winds are outflows of gas from the rotating disks of dust and gas around young stars, from which planets form. These winds are not a single phenomenon but a class of mechanisms that remove material from the disk, shaping its mass, size, and chemical composition. They play a critical role in the evolution of the disk and therefore in the conditions under which planets assemble, migrate, and retain their atmospheres.
The concept of disk winds emerged in the 1980s from theoretical work on angular momentum transport in accretion disks, with photoevaporation models developed in the 1990s. Observations of molecular outflows and ionized gas in star-forming regions have since provided strong evidence.
The winds are driven by magnetic fields or high-energy radiation from the central star. Magnetically driven winds arise because the disk's ionized gas is threaded by magnetic field lines that rotate with the disk; centrifugal forces fling material outward along these lines, carrying away angular momentum. Photoevaporation, by contrast, occurs when X-rays and ultraviolet light from the star heat the disk's outer layers, causing gas to escape thermally. Both processes remove gas that would otherwise be incorporated into planets or affect their orbits.
Disk winds are key inputs for models of planet formation and migration, helping explain the observed mass distribution of exoplanets and the clearing of gas from young planetary systems.
The same magnetic mechanism that drives protoplanetary disk winds also powers the jets seen shooting from young stars, which can extend for light-years.























