17P/Holmes
 

Click photo to see a larger image.
or
 Largest Image (1 meg)
 

 
Description: This comet was discovered in 1892 and has a period of ~7 years. During its appearance in October of 2007, it brightened by a factor of about a half a million. This is the largest known outburst of any comet, though the reason for this outburst is not known. The tails of the comet are not prominent since they were in our line of sight, but some remnants of the blue ion tail are visible to the lower left. The colors of the comet are caused by molecules fluorescing in sunlight. CO in the ion tail fluoresces blue, while C2 in the main body of the comet fluoresces green. I have a mouse-over page that shows the application of a special filter to reveal hidden structure in the comet. In addtition, there is an interesting animation (1.4 megs) that shows some structure breaking away from the comet. Be advised that Internet Explorer seems to 'posterize' the animation, but FireFox and Safari work well. A larger animation (3.4 megs) shows this disconnect more clearly (except on Internet Explorer).
 
Dates: 8 november 2007
 
Equipment: AP130 @ f/6, Mach1GTO, STL11000
 
Exposure: RGB: 30--26--32 minutes (Astrodons)
 
Note: This is my first image of a comet.