Astronet Астронет: Астрономическая картинка дня Найдены пылевые диски в старых планетных системах
http://variable-stars.ru/db/msg/1200464/eng
Old Planetary Dust Disks Found by SST
<< Yesterday 19.10.2004 Tomorrow >>
Old Planetary Dust Disks Found by SST
Credit & Copyright: T. Pyle (SSC, Caltech), JPL, Caltech, NASA
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.

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

Русский текст
Based on Astronomy Picture Of the Day

Rambler's Top100 Яндекс цитирования