Astr110 Photography Projects, Fall 2005

Blue Snowball, Jennifer Mitchell

The Blue Snowball (also known as NGC 7662) is a planetary nebula, formed from the layers of a red giant star after it has depleted the rest of its fuel and collapsed at a high temperature. When this occurs, a star becomes a white dwarf, and during its time of collapse, it releases gases that form colorful rings that surround the newly formed white dwarf. It is a small nebula, with a visual magnitude of about 8.3. It was discovered in 1784 by the well-known astronomer, William Herschel, and was found within the constellation Andromeda, roughly 2,200 lightyears away from Earth.

The picture above shows the light, glowing blue-green rings/layers of gas that surround the white dwarf star, which were expelled from the star after collapse. In the center of the ring is the dwarf star, a bright blue color, which is what gives this nebula its name. The calculated linear size of the nebula is about .31 light years or 30", a little under half an arc minute.

References:
The Encyclopedia of Astrobiology Astronomy and Spaceflight

Cline Observatory at GTCC

Astronomy Picture of the Day