NGC 7662 (Blue Snowball) -- Planetary Nebula in Andromeda
The bright Planetary Nebula NGC 7662 is a joy to view even in a small telescope. In the
110mm refractor at 220-power it shows its famous greenish-blue color, and a distinctive
inner-ring. Nebula filters are not necessary, but I found that they help accent the interface
between the inner and outer rings in the nebula. Keep in mind that this planetary nebula is
small, so it will appear star-like at low-power. But anything above 100x the bluish-disk will
stand out and NGC 7662 responds well with high power so go as high as the stability of
the atmosphere will let you.
There is so much more to see in this planetary nebula than can be detected with a small
refractor. Those with large-Dobsonians or telescopes equipped with a photographic CCD,
should shoot for the outer-spherical halo that extends outwards 134 arcseconds, the central
star at magnitude 13.2 (variable?) and the famous FLIERs [Fast low-ionization Emission
Regions] that light up the outer ring with spark-like marks. None of these I could see with the
4-inch refractor, but I did not despair – the Blue Snowball is a pretty cool sight in any telescope.