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2007-04-24 13:43 Clh288 1280×1248×8 (201934 bytes) A [[Hubble Space Telescope]] (HST) image of [[NGC 6818]] Credit: HST/[[NASA]]/[[ESA]]. http://www.spacetelescope.org/images/html/opo9738c21.html == Licensing == {{PD-Hubble}}
This Wide Field and Planetary Camera 2image of NGC 6818 shows two distinct layers of gas (with dust): a spherical outer region and a brighter, vase-shaped interior 'bubble.' Astronomers believe that a fast wind - material propelled by radiation from the hot central star - is creating the inner elongated shape. The central star of the planetary nebula appears as a tiny blue dot. The material in the wind is traveling so fast that it smashes through older, slower-moving stellar debris, causing a 'blowout' at both ends of the bubble (lower right and upper left).
来源
ESA/Hubble
提供者
Robert Rubin (NASA/ESA Ames Research Center), Reginald Dufour and Matt Browning (Rice University), Patrick Harrington (University of Maryland), and NASA/ESA
简短标题
Planetary nebula NGC 6818
使用条款
Creative Commons Attribution 4.0 International License