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30. M57, Ring Nebula
Notes: M57 lies a thousand light years beyond M27, the Dumbbell Nebula, but it is still close to the Solar System relative to the size of the Galaxy. But it has a faint apparent magnitude of 8.8, so it shows up small at 230 arcsec in our field of view, which is almost 120 arc min. You will probably want to zoom in. According to Wikipedia:
Even a 7.5 cm (3 in) telescope will reveal its elliptical ring shape [to a viewer]. The interior hole can be resolved by a 10 cm (4 in) instrument at a magnification of 100×. Larger instruments will show a few darker zones on the eastern and western edges of the ring, and some faint nebulosity inside the disk. The central star, at magnitude 14.8, is difficult to spot.
The central star shows up faintly in this image.
Technical notes: The sky was clear and dark except for a half moon high in the SSW. The night was quiet. The guide scope is slightly defocussed. The PHD integration time was set to 1. Zoom in/out with ⌘↑(+/-) (Mac), ctrl (+/-) (PC).