The remnant of a supernova that occurred a matter of some eight millennia ago, the Owl Nebula lies within Ursa Major, close to the well known Plough or Big Dipper formation. It lies close to an imaginary line between the two stars that form the 'base' of the Plough, Phecda and Merak. This prominent position would make it easy to find in the night sky, if not for its faintness, but at twelfth magnitude it requires a comparatively powerful telescope to resolve.
The nebula itself is the result of a giant star throwing off its outer shells during a supernova, and in this case three distinct shells are detectable, expanding outwards in an approximately spherical pattern. Not all the shells follow this pattern, however, and the deformed inner shell is angled at a line of sight that produces two distinct and symmetrical darker patches within the roughly circular overall shape of the nebula. The resemblance of these two elliptical forms to two large eyes set in a round face give the nebula its common name: the Owl Nebula.
While its outer shells expand out into space, the original giant star that formed the nebula has collapsed to form a compact, highly dense White Dwarf at the heart of the nebula's structure.
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