protoplanetary disk

(redirected from Circumstellar disks)
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protoplanetary disk

[‚prōd·ō‚plan·ä‚ter·ē ′disk]
(astronomy)
References in periodicals archive ?
One important consideration for planetary formation is the dispersal rate of the circumstellar disk of gas and dust around a host star.
The findings support the notion that at least some massive stars form as their smaller siblings do, by packing on infalling material from a circumstellar disk.
These polarized images reveal regions of high-density dust typical of a circumstellar disk.
In contrast, the standard model of a circumstellar disk, which assumes that a star develops in isolation rather than in a crowded cluster, predicts no such truncation.
Washington, November 20 (ANI): A team of astronomers has captured the first direct, well-resolved infrared images of a circumstellar disk around a young massive star called HD 200775, to illuminate a massive star formation process.
The remaining 42 papers are presented in accordance with the conference sessions, which were dedicated to dynamical processes, stellar mass loss as origin of circumstellar material, structure and dynamics of circumstellar disks, and evolutionary effects in active OB-stars.
Mounting evidence suggests that circumstellar disks provide the spawning ground for planets.
Loads of tiny diamonds, each measuring one micrometer are located in the material that surrounds some stars - their circumstellar disks.
A rocky core could have formed despite the high temperature, but astronomers theorize that circumstellar disks contain far less rocky material than ice and gas.
The formation of circumstellar disks ranks as the first step in making planets; without them, the stars "aren't going to be forming solar systems," says Hester.
These and other findings suggest that V376 Cas and V633 Cas -- just a few hundred thousand years old -- are still forming their circumstellar disks from the dust cloud in which they were born.
The answer to that astronomical question has eluded scientists because of poor estimates of the amount of mass in circumstellar disks and uncertainties about whether most disks stick around long enough to form planets.