This object, nicknamed the Blue Snowball, is a planetary nebula located 6400 light years away in the constellation of Andromeda at a declination of +43 degrees. This magnitude 8 PN spans 30 arc-seconds in our apparent view, which corresponds to a diameter of 1 light year.
This is probably the only snowball I will ever see in East Texas. The magnitude 12 central star is easily visible in the image but is not visible through the eyepiece.
Over the last few thousand years, the dying star has expelled gas into space in waves. Sometimes this results in faint outer rings, as with the Cat's Eye Nebula and Ring Nebula. I tried to capture some of this faint outer region for this object, but the difference in brightness between the central and outer regions makes it tough to capture both regions in one image.
This PN is similar in shape to
NGC 6826. I believe that we are looking at this bi-polar nebula at about 45 degrees from end-on, with the long axis going from 8 o'clock to 2 o'clock. Our viewing angle makes the inner bright torus ring look more like an oval. Our angle also makes the 11 o'clock and 5 o'clock portions of this ring brighter because we are looking through more of its thickness in those directions.
I generally don’t like nicknames, but this one isn’t so bad. According to Steven James O’Meara, the nickname originated with Leland Copeland, who wrote in the February 1960 issue of Sky & Telescope that this object “looks a light blue snowball". Note the use of the word “light”. Most expert observers agree that this object has only a slight blue glow and not a strong vivid blue color.
Comments