re: NASA Mars 2020 Rover Details Emerge
EM, not so fast. It is to say the least 'misleading' to make off the cuff statements like "Resources from Mars, such as rocks, could be used to generate fuel or other parts that would enable future human exploration" without further clarification .
First off, for a very long time to come, rock would only be useful if it contained a high fraction of water\ice. That water could be converted electrolytically into oxygen and hydrogen or other fuel, depending on the process details. Any such process takes a lot of electrical power, which means delivery of some serious infrastructure to where all that is to happen, which is way off into the future. The US spenditure on space efforts is not up to par to support anything major getting delivered to Mars, let alone some appropriately sized robotic cottage industry able to support human presence.
Second, much easier to make fuel out of is Mars' "air". At say 1/20th the pressure on earth, and 95% CO2 even that 'air' isn't exactly ready-made for humans, and so, it too needs major hardware and power to get converted into breathable air for humans. All human support technology needs to be clearly demonstrated prior to sending anyone there, if one intends to have them 'live' on Mars. Of course, that is, if one would want to call being locked inside spacesuits and small cabins 'living'.