Last updated on April 18, 2014 at 6:30 EDT
Images of the Cygnus Loop
14 of 32

Images of the Cygnus Loop

March 17, 2003
This supernova remnant in the constellation Cygnus, known as the Cygnus Loop, is roughly 20,000 years old. It is generally circular in shape except for a break-out towards the south. In addition, there are many bright, filamentary structures. The ROSAT PSPC observation has allowed the temperature and density structure to be studied on a fine angular scale.