ROSAT PSPC contours (0.1-0.4 keV) superposed onto an optical image of NGC~253. The X-rays show hot gas (2x10^6 K) filling both halo hemispheres. The disk of the galaxy is not completely edge-on however, the north-western part being nearer to us, and the soft X-rays emitted close to the inner disk, from the far side of NGC 253, are absorbed within the intervening north-western spiral arms, leading to the observed "hole" in the diffuse emission along the north-western rim of the galaxy.

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