Figure 13-10: RIVUXG Europa Dark lines crisscross Europa’s smooth, icy surface in this false-color composite of visible and infrared images from Galileo. These lines are fractures in Europa’s crust that can be as much as 20 to 40 km (12 to 25 mi) wide. Only a few impact craters are visible on Europa, which indicates that this satellite has a very young surface on which all older craters have been erased.