Once drill sites have been established then facilities could be constructed opening a whole new range of difficulties. A 28 minute delay (as with Mars Rover Sojourner) would disallow remote operators from receiving data in real-time. Multilayered controls would allow machine autonomy while operating within a set of boundaries. Researchers at the Autonomous Systems Laboratory in Australia were able to operate a remote drag-line excavator remotely for 50 consecutive dig cycles lasting 53 minutes with no operator interference. Computer algorithms calculated the size and scope of each dig cycle while laser analysis determined when each bucket was full while digital terrain maps evaluated landscape changes. Though the great distances involved would make excavation on Mars more challenging, ultimately, it requires the same basic technique modified for the specific landscape.

Once extracted, the minerals and ores would need to be processed, also difficult given the great distances. Once again, machinery would need a great deal of autonomy with regular checkups from ground controllers. The Mars Direct Mission, detailed in part in 1998 report, suggests a staggered operation in which unmanned exploratory rovers would be sent prior to a ground crew in order to spur resource production ahead of human presence. Secondary backup craft would also be sent alongside to serve as return vehicles. Astronauts could use the rovers to explore dig sites in transit to Mars reducing downtime and reducing timing differences as the crew moves closer. Once on the surface, the mining crew would be able to work at much greater efficiency, building production and housing facilities eventually allowing the base to become completely self-sufficient. Most everything aside from the human crew would be sent...

Abundance of ore could be stored on the martian surface waiting for another crew or further development of mining operations.
Truly, the limitations of a remote, off-world mining operations are only what we allow them to be, in this case, capital investment. The technology required to produce raw materials and then refine them in situ exists today. Advances in automated computer technology make the physical operation that much easier and less risky while experimental rockets and propulsion techniques, such as the VASIMIR (Variable Specific Impulse Magnetoplasma Rocket)

could reduce transit times to days rather than months. Ore production and refinement off-world could be lucrative enough to fund itself and future missions.

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