The Blue Snowball is a planetary nebula located in the western area of Andromeda constellation. Planetary nebulas are named because of their shape which is similar to planets in many cases. In reality they are remnants of dead, low mass stars. It is one of the easiest planetary nebulas to observe using small instruments, making it perfect for beginning observers. It has a blue/green color, with a faint central star with the temperature of about 75,000K (Kelvin). This nebula has had some debate over the distance. In the 50’s the Slanlnate Pleso Catalogue recorded the distance at about 1800 light years. Later in 1963 C.R.O’Dell concluded it was 5600 light years away.
This image has been taken in different color filters, and composited to show an enhanced portrayal of the nebula. The Blue Snowball is the large blue disk in the image, thus the name given to it. There is an interesting arc towards the center, showing that the nebula expanding. Using O'Dell's distance we were able to calculate the diameter of this nebula to be about 1 light year.
Bennett, Jeffrey, Megan Donahue, Nicholas Schneider, and Mark Voit. The Cosmic Perspective. 6th ed. San Francisco: Addison-Wesley, 2010. 543-44.
Darling, David. Blue Snowball Nebula (NGC 7662) . Web. 6 Dec. 2010. <http://www.daviddarling.info/encyclopedia/B/Blue_Snowball_Nebula.html>.
Normandin, George. Planetary nebula NGC 7662 in Andromeda. 29 Oct. 1997. Web. 6 Dec. 2010. <http://www.kopernik.org/images/archive/n7662.htm>.
|Right Ascension (J2000)||23:25:54|
|Filters used||blue(B), green(V), red(R), and clear(C)|
|Exposure time per filter||1x60 seconds in C,V,R: 300 seconds in B|
October 29, 2010 (C)