From CNN.com:
The mosaic image is made up of 30 separate pictures made by the Chandra X-Ray Observatory, which monitors space through X-rays that filter out the cosmic dust that can obscure images made with optical devices.
http://www.cnn.com/2002/TECH/space/0...eut/index.html
X-rays do not filter out cosmic dust. Cosmic dust "filters" out optical light (and other wavelengths). X-rays are simply not or are barely affected by the dust.
CJSF
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