 FACT: The large ground vehicles used by the digging teams would be  unnecessary, as having a low gravitational force would mean that a  large digging rig would simply float to its destination using small  thrusters sparingly. However as there was a time limit on the  mission it might simply have been more efficient to put the drills  on the ready made vehicles than to design and build a platform. This  is not to mention that digging anything in zero