Cygnus Loop — nebula, shown live in Cosmoscope, a real-time 3D map of the universe.
The ghost of a star that died twenty millennia ago — a vast shock bubble still expanding through the gas of Cygnus. Its brightest wisps are the famous Veil Nebula.
Cygnus Loop is placed at its true position on the sky and at its real measured distance, not as a flat backdrop. Fly out from the Sun in the live 3D view and watch it change from a point of light into structure as you approach, with the scale bar showing just how far out you have travelled.