Planetary Nebula M57

Planetary Nebula M57

Planetary Nebula M57 is a expanding shell of gas puffed off an intermediate mass star in its final stages as it becomes a white dwarf.
The image is a composite of three separate images taken in three different filters (Blue = Johnson B, Green = Johnson V, Red = Cousins R). Each image was a five minute exposure with the 20-inch telescope and the U42 CCD camera.