Pickering's Triangle from Kitt Peak

Explanation: Wisps like this are all that remain visible of a Milky Way star. About 7,500 years ago that star exploded in a supernova leaving the Veil Nebula , also known as the Cygnus Loop. At the time, the expanding cloud was likely as bright as a crescent Moon , remaining visible for weeks to people living at the dawn of recorded history . Today, the resulting supernova remnant has faded and is now visible only through a small telescope directed toward the constellation of Cygnus . The remaining Veil Nebula is physically huge, however, and even though it lies about 1,400 light-years distant, it covers over five times the size of the full Moon . In images of the complete Veil Nebula , studious readers should be able to identify the Pickering's Triangle component pictured above, a component named for a famous astronomer and the wisp's approximate shape . The above image is a mosaic from the 4-meter Mayall telescope at the Kitt Peak National Observatory located in Arizona , USA .