Take a look at this remarkable image from HiRISE showing Mars Science Laboratory Curiosity and the tracks it made during the first few drives in Gale Crater. Scientists will be keeping a close eye on these tracks so as to track the rate of surface change on Mars.
|Click to see high resolution version from HiRISE.|
Unlike Earth's Moon, Mars does have wind and other weather, so tracks will get covered up. Examining these tracks will let scientists determine the quantity and frequency of dust deposits in Gale Crater, as well the rate of erosion. Knowing how often features on the surface of Mars can change or be covered up will help current and future missions to Mars; let me explain how:
Imagine a Mars rover takes a long distance shot and sees something slightly protruding out of the surface. If we have a good idea of the rate of change on Mars then we can determine how long that feature will be there before getting covered up. If it will be covered up in a matter of days then it would become a higher priority then something that might be visible for a few weeks or months.
If you send a manned mission to Mars it is essential that they are knowledgeable about the rate of surface change. If you were going to take a walk on Mars you would make some reference points so as not to get lost. If you weren't aware of the rate of change you might use a field of hematite (blueberries) to the right of base camp as a reference point, not realizing that it might be covered up in a couple hours. You could get lost because you didn't know how fast something could get covered up!
As you can see, images like the one above are essential to our understanding of Mars and could help us save the lives of future explorers and billions in hardware!