The Blue Snowball is one of the
brightest and most fascinating planetary nebulae in the sky.
This planetary has an integrated magnitude of 8.6 packed into a very
round ball 17" in diameter.
The non-stellar nature of this
object is apparent even in smaller scopes at low power.
At higher magnifications it appears as a very bright, round ball.
Many observers report a distinct blue-green hue. In a 6-inch I
felt that there was, "some hint of the edges being
brighter." Look for a faint star just to the east of the
Above: the view in a 6" at 50x. North is down, east is right.
Note how small it is.
My observing notes using my 18-inch:
I had never before observed this
planetary nebula in a large instrument. It was a real treat! Even at
82X it was large, bright and obvious. My notes for 166X simply
say "wonderful" and "amazing!" But it was at
333X times that this planetary really shined, despite the poor
seeing. It is nearly round and has a high surface brightness.
The edges are not distinct -- they appear lumpy, almost like looking
at a barely-resolved ball of yarn. It has sort of
"ropey" edges. I was surprised that with averted
vision I could plainly see a small, dark, round core (making
up perhaps 10% of the object). Another surprise was an apparent
bright area just to the south of the dark center.
The image above is
taken from the DSS using SkyView. It shows a 1/2o field
with the same orientation as above. Note that even thought it is
small the nebula (center) has a non-stellar appearance.
This HST image reveals the fine structure inside of the nebula.