Borut Prasnikar from Skofja Loka, Slovenia, took this image of Comet PANSTARRS at Krizna Gora, Slovenia, on March 21. He used a Nikon D300 DSLR with a 300mm f/4 Nikkor lens set at f/4. He set his camera to ISO 800 and took twenty-one 20-second exposures, which he stacked. Finally, he subtracted some of the background to show the comet's tail structure better, and created this final image.
Borut Prasnikar