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.
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.
"In the nightgown of the sullen moon, How the windows lean into the room, In the nightgown of the sullen moon."
-They Might Be Giants