Copyright © Astronomy Roadshow All rights Reserved
Some photographs show very shallow tracks made by the rover. The vehicle would have the weight of itself plus the two astronauts. And yet beside the rover, the astronauts footprints alone are deeper than those made by the Rover. How come eh?
Imagine the scene in a realistic mode; This soil gradually built up through distant impact / deposits and settled. The Rover is coming to a stop on soil that has been there for countless millions of years. The wheels gently passes over at less than 1km per hour to a stop and the astronauts depart to explore... shallow tracks.
1) Now the astronauts disturb the soil instead. This time they make an imprint, twist around to unload equipment, or to take a picture, pose for a picture and so on. The same soil is being disturbed over and over, becoming more dislodged upon each impact.
... Full answer in the book.