Explanation: Why are some older stars surrounded by dust? Observations from the Spitzer Space Telescope by a team led by George Rieke (U. Arizona) were expected to show that young stars, on the order of one million years old, have large dust disks, while relatively older stars, between 10 and 100 million years old, have none. The conventional wisdom was that the dust disks surrounding young stars were still forming planets, while in older systems these disks had dissipated after planets had already formed. Unexpectedly, they found some older stars with the infrared glow of impressive rings or disks of dust. A possible explanation is that the old disks are remnant debris from violent collisions between many forming planets of rock. Resultant dust rings from such a scenario are depicted by an artist's illustration above.

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)
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NASA Official: Jay Norris. Specific rights apply.
A service of: LHEA at NASA / GSFC
& Michigan Tech. U.

Publikacii s klyuchevymi slovami: Spitzer space telescope - dust disk - planet formation - pylevoi disk - Formirovanie planet Publikacii so slovami: Spitzer space telescope - dust disk - planet formation - pylevoi disk - Formirovanie planet
Sm. takzhe: Pylevoi disk vokrug Fomal'gauta Igra: krushenie superplanet Tumannost' Oriona v teleskop "Spitcer" Tumannost' Severnaya Amerika v infrakrasnom svete 55 Raka-e: klimat v mire iz lavy Zvezdy v centre Galaktiki Dvoinoi pylevoi disk zvezdy HD 95086 Vse publikacii na tu zhe temu >>