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Astr110 Photography Projects, Fall 2005

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Blue Snowball, Jennifer Mitchell

Blue Snowball

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.

The Encyclopedia of Astrobiology Astronomy and Spaceflight

Cline Observatory at GTCC

Astronomy Picture of the Day

Right Ascension (J2000) 23:25.9
Declination (J2000) +42:33
Filters used blue(B), green(V), red(R), and clear(C)
Exposure time per filter 300 seconds in B, 60 seconds in CVR
Date observed

November 6, 2005 (VR)
November 9, 2005 (C)
November 10, 2005 (B)