On release from the Interorbital Transporter, this forward part of the spacecraft becomes a re-entry vehicle in its own right, and can land upon Mars surface to become an advance base for coordinating landfall of the later following cargo landers. Although nominally identified as a 'heavy' lander, the vehicle has a lightweight internal geodesic frame supporting a foam and carbon fibre casing, with a sintered asteroid-debris light-ceramic heatshield. Once landed, the empty retrofuel tanks can be lowered to form safely buried storage tanks for collection of various fuels, gases or water. http://www.eosmarsprogram.org/Page31-09-Space.html