The new observations may give a key to understanding the early stages of our solar system. On the basis of comparisons among the mass accretion rates of 42 young stars derived from ground-based observations, the team reports evidence supporting an emerging theory. Here's how it works. When the disks are very young, some of the material of the disk spirals inward, crashing onto the stellar surface. From the energy released in these impacts, astronomers can determine how rapidly matter accretes onto the star along columns regulated by solar magnetic fields.
Young stars accrete material the fastest, the team reports.
Not all the material falls onto the central star, however. A fraction of the impact energy may drive collimated supersonic jets of material that shoot outward perpendicular to the plane of the disk into the interstellar medium. How stars redirect accreting material into jets remains to be ascertained. But these are not the only processes that may be at work. As the star and disk age, astronomers believe that some of the gas and dust congregates into planets.