Amid the bright stars, large nebulae and plentiful open clusters of the late autumn sky there is a sprinkling of great planetary nebulae to feast upon. Let's ramp up the excitement immediately with the marvellous Blue Snowball in Andromeda, a smalt but beautiful planetary nebula more soberly known as ?G? 7662. The Blue Snowball shines at eighth-magnitude, making it well within the range of small telescopes, with most observers perceiving a faint blue or greenish colour, with the hue more apparent at low powers. A telescope in the 150-200mm class should reveal a double ringed or shell structure with a brighter well-defined inner ring spanning some 15 arcminutes, surrounded by a larger, dimmer envelope of gas. Sixth-magnitude 13 Andromedae is a useful guide to finding it, lying just one half of a degree north-east.
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