clic here for 100% size 2004 x 1336 (288 kB)
Comet 73/P Schwassmann-Wachmann 3 is a periodic comet appoaching our Sun every 5.5 years.
This comet was seen to split into several large pieces during the close-in part of its orbit in 1995.
The loose ball of ice and dust left over from the early solar system is very sensitive to disintegration when getting close to the sun.
16" cassegrain in secondary focus at f/10
About this Image
However, this time the comet seems to be rapidly disintegrating with dozens of fragments, named alphabetically, now stretching several degrees across the sky.
Checkout the Hubble close-up on fragment B and G from this April: here.
The image on top od this page shows fragment C approaching the Ring Nebula M 57 in Lyra.
Find an animation over 60 minutes of the comet's head in 100% size here.
The image below shows the rapid movement in this short exposure of approx. 30 minutes, guided on the stars. 
Technical Details
Optics
guide scope TEC-140 f/7
Mount
MK-100 GEM
Camera
SBIG STL-11000M at -20C, internal filter wheel, external and internal guider
Filters
Astronomik LRGB
Date
May 07-08, 2004 22:00 - 2:25 UT (till dawn).
Location
Wildon/Austria
Sky Conditions
mag 5 sky, average transparency, temperature 12 C
Exposure
Guiding on comet head: L:R:G:B = 4000:600:600:600 sec (200-sec sub-exposures);
Guiding on star near M57: R:G:B = 800:800:800 sec(200 sec sub-exposures);
all binned 2x2.
Processing
Image aquisition and calibration in Maxim DL 4.11, median stacking for comet guided frames; DDP applied;
M 57 area average aligned, DDP;
stacked comet guided image blurred in outer area and added to the M 57 image in lighten mode;
further processing in Imagesplus and Photoshop; North is up;