M83 is a spiral galaxy about 15 million light-years away from the Sun. Similar to our own milkyway galaxy, its arms are clearly seen in the optical light (coloured). Several hitherto unknown X-ray sources are seen in the disk of the galaxy. But the X-ray emission of M83 is dominated by an extended component (contour lines) distributed almost over the whole galaxy, even in the optically bright region. This diffuse emission has its origin in very hot gases raising from the disk as galactic winds or "fountains" and forming an extended galactic halo. This is probably a result of active star forming.
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