Russell Kille Astro Photos
Celestron CPC 1100 Altazimuth Mount
Hyperstar ASI 224MC Non Cooled

NGC 6781 Planetary Nebula aka. Ghost of the Moon Nebula
Magnitude: 11.4
Distance: Aprox: 3,100 light-years
Constellation: Aquila

This lovely 11th-magnitude planetary nebula, first seen by William Herschel, lies in a fine field of the Milky Way and can be glimpsed in a moderate-sized telescope. This ring-like nebula consists of glowing gas cast off by a dying star some 3,100 light years away. The nebula spans about 3′, big for a planetary nebula, which means it has a true diameter of about 2 light years. At magnitude 11.4 it’s quite faint and has a low surface brightness. That makes it a challenge for a 4″ to 6″scope, and dark sky is essential if you want to spot it visually in any instrument. A nebula filter is a big help.

The central star, a mid-sized star like our Sun, is throwing off the outer layers of its atmosphere in a last gasp of life. The star is about 16th magnitude so it’s very hard to see visually. The nebula will dissipate over the next many thousands of years, and the central star will remain as a white dwarf, a hot glowing cinder which will cool slowly over billions of years.