Cygnus Loop

The Cygnus Loop (radio source W78, or Sharpless 103) is a large supernova remnant (SNR) in the constellation Cygnus, an emission nebula measuring nearly 3° across.^[1] Some arcs of the loop, known collectively as the Veil Nebula or Cirrus Nebula, emit in the visible electromagnetic range.^[1] Radio, infrared, and X-ray images reveal the complete loop.

^ ^a ^b Murdin P (2001). "Cygnus Loop". In Murdin P (ed.). Encyclopedia of Astronomy and Astrophysics. Bristol: Institute of Physics. Article 5297.^{[permanent dead link]}

[Murdin-1] Murdin P (2001). "Cygnus Loop". In Murdin P (ed.). Encyclopedia of Astronomy and Astrophysics. Bristol: Institute of Physics. Article 5297.^{[permanent dead link]}

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