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Cygnus Loop Supernova Remnant (or Veil Nebula)

The Cygnus Loop supernova remnant in the constellation Cygnus is roughly 15,000 years old. It is about 70 light years in diameter at a distance of 1400 light years. This makes it appear huge in the sky, with an apparent diameter six times that of the full moon. The Cygnus Loop offers a unique opportunity to learn the details of the interaction of a supernova blastwave with interstellar clouds. This ROSAT high-resolution observation in X-ray has allowed the temperature and density structure to be studied on a fine angular scale. South is to the right here.  An image of the Veil nebula in visible light reveals a fine filament structure.

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