Intriguing Dimples Near Eagle Crater on Mars . ... Credit Copyright: Mars Exploration Rover Mission , JPL , NASA Explanation: What are those unusual looking dimples? Looking back toward Eagle crater , its landing place on Mars, the robot rover Opportunity has spotted some unusual depressions in the Martian soil. ... Further analysis of rocks photographed by Opportunity has yielded evidence that Opportunity has landed on an evaporated shoreline of an ancient salt-water ocean . ...