Bruce Murray Space Image Library

Comet PANSTARRS, Earth, and a coronal mass ejection as seen from STEREO-B

Comet PANSTARRS, Earth, and a coronal mass ejection as seen from STEREO-B
Comet PANSTARRS, Earth, and a coronal mass ejection as seen from STEREO-B NASA/NRL/STEREO

For an explanation of this image, see this blog entry.