(See description below)
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.