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[–] 6 points 1 year ago (1 child)

Fun fact: Steel rails on the moon aren't the best idea. Instead, roads made of sintered regolith + trains with ceramic wheels are cheaper to build and have the same efficiency that steel wheels+ steel rails have.

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  • [–] 1 point 1 year ago

    I wonder if they are having trouble with microplastics in the Paris Subway system. I marveled at their quiet subways while I was there and saw they use what looks like rubber wheels on their carriages.

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