Amazing, the things a birds-eye view allows you to see. Here’s a color image from the HiRISE camera on board the Mars Reconnaissance Orbiter showing the tracks of the Curiosity rover. In this most recent HiRISE image of the MSL rover, the tracks are visible from Yellowknife Bay to its location on 11 December 2013, several kilometers to the southwest. Even though some of these tracks are more than a year old, they are still visible.
As HiRISE team member Christian Schaller said via Twitter, “Take only pictures; leave only footprints.” In this case, HiRISE took the pictures while MSL left the footprints!
HiRISE principal investigator Alfred McEwen explained the image: “Curiosity is progressing from the bright dust-covered area to a region with a darker surface, where saltating sand keeps the surface relatively free of dust. The scenery seen by the rover will be getting more interesting as it progresses toward Mount Sharp.”
See a black and white image below, where you can actually see Curiosity, too: