A large number of planetary nebulae can be found within the NGC and IC catalogs and are available elsewhere on this site (see here). As illustrated by the image below, planetary nebulae are beautiful objects to look at thanks to the glowing and colourful gaseous shrouds which make their planetary appearance and colouration possible as a result of stars having exhausted their nuclear material and having reached the last stages of their life. Some of the more exotic planetary nebulae include the Cat's Eye (NGC 6543), the Saturn Nebula (NGC 7009), the Ghost of Jupiter (NGC 3242) and the Owl Nebula (M97).

George Abell's examination of the Palomar Observatory Sky Survey in the mid 1960's yielded 86 planetary nebulae which have proven to be an observer's dream challenge, for many of these celestial objects are not only very faint in magnitude even under very dark skies but are also relatively large with dimensions often measured in minutes in lieu of seconds. Later analysis of Abell's catalog revealed that at least four of these objects, namely Abell 11, 32, 76 and 85, are not planetary nebulae at all. For the avid observer, an O-III filter is highly recommended in order to have any hope of visually detecting these elusive wonders. Abell's planetary nebulae have been classified under a web page of their own on this site (see here).

Note: NGC 3587 is one of four planetary nebulae within the Messier catalog along with M27 (Dumbbell Nebula) in Vulpecula, M57 (Ring Nebula) in Lyra and M76 (Little Dumbbell Nebula) in Perseus. M97 is commonly referred to as the Owl Nebula owing to its striking resemblance to an owl thanks to the circular disk formation and two smaller inner circles which resemble an owl's head and eyes. In contrast to M76 (Little Dumbbell Nebula) and which represents one of the dimmest entries within the Messier catalog, the Owl Nebula is relatively quite bright for a planetary nebula with a magnitude of 9.55 and a surface brightness of 11.9. As indicated by the image below, M97 is comprised of multiple shells and is believed to physically resemble a torus cylinder. The Owl Nebula was discovered by Pierre Mechain in 1781 and nicknamed as such by Lord Rosse in 1848. Although distance estimates vary dramatically and range from 1,300 to 12,000 light-years away, many sources cite an intermediate distance of 2,600 light-years away and a diameter of 2,000 light-years across.

As with all planetary nebulas, a "central" star is responsible for the impressive and colourful shrouds of gases, for it represents the source of the massive stellar explosion. In this particular instance involving M97, the 16th magnitude star at the center of the shroud is the source of the gaseous envelopes that surround it. Studies suggest the central star leading to this impressive planetary nebula exploded approximately 6,000 years ago.

To the immediate east of M97 lies QSO J111504.45+550143.6 (mag 19.12). This quasar is associated with a redshift of z=1.1883 and which translates to a receeding velocity of 65% the speed of light. Studies have determined this quasar to lie at an impressive distance of 9.015 billion light-years away!