Cresent Europa. NASA public domain image colelction.

This mosaic of Europa, the smallest Galilean satellite, was taken by Voyager 2. This face of Europa is centered at about the 300 degree meridian. The bright areas are probably ice deposits, whereas the darkened areas may be the rocky surface or areas with a more patchy distribution of ice. The most unusual features are the systems of long linear structures that cross the surface in various directions. Some of these linear structures are over 1,000 kilometers long and about 2 or 3 kilometers wide. They may be fractures or faults which have disrupted the surface.
NASA Identifier: GPN-2000-000469