[xavxav]

1. the article explains how many materials could potentially be sourced on the moon and provides potential magnet compositions to address that as well. 2. The moon weighs ~8.1 x 10^19 tons, if we use their iron based magnet design and ship everything from the earth (iron is present on the moon), it would require ~1 million tons aka 10^6 tons or approximately 0% of the weight of the moon. 3. See above.