Well check this out: if it’s big enough and can collect enough solar energy, it can be a self-powered gargantuan electromagnet and CREATE a magnetosphere for Mars itself. And the moon has a higher silver content than earth, which a) won’t tarnish in the vacuum of space and b) is more conductive than copper or gold!

Aluminum alloy structures, silver circuitry, we could build this thing without sending ANY of it’s raw materials from earth. It’s all already up there waiting for us… … Some assembly required :p