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It’s not just Saturn that sports some celestial bling; many stars have rings or disks full of debris surrounding them, all leftovers from the process of planetary formation. That includes our Solar System, with its asteroid belt between Mars and Jupiter, as well as the Kuiper belt, the thicker, donut-shaped disk of icy rocks and comets that lies just beyond Neptune.
Somewhere within those stellar disks are important hints about how planets formed, as well as clues to the history of their host systems. That search now includes Gongjie Li, Billy Quarles, and Nathaniel Moore, three School of Physics researchers who recently won a $523,145 grant from NASA’s Astrophysics Theory Program (ATP) to study so-called “stellar flybys,” where stars fly over those discs, changing their form, scattering other celestial bodies hither and yon, and possibly giving birth to solar systems like our own.
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A stellar flyby “is a common process, since most stars form in stellar clusters with a high number density of stars nearby,” says Li, an assistant professor in the School of Physics. “As the stars fly close to the debris disk, it will gravitational pull disk particles and excite their orbits.
This changes the morphology of the disks, and the observed image of the debris disks could provide clues on the flybys and the formation environment of the planetary systems.”