• @maryjayjay@lemmy.world
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    648 months ago

    Internal calculations were are all done in metric, but converted to traditional US units because many of the astronauts were pilots and more used to them

    • @Vilian@lemmy.ca
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      218 months ago

      imperial system is based on metric(on wikipedia) so they calculed on metric, converted to imperial, that is basically metric but worse

      • @Pipoca@lemmy.world
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        178 months ago

        Kinda sorta not really.

        One problem with units is defining them precisely.

        For example, a meter is ostensibly “one ten-millionth of the distance from the equator to the North Pole along a great circle”. That’s not exactly precisely defined because the earth isn’t a perfect sphere.

        So currently, a meter is defined to be the distance light travels in a vacuum in 9192631770 / 299,792,458 hyperfine structure transitions of caesium-133.

        Rather than doing the same sort of thing with updating the standard definition of a foot or pound, the US just piggybacked off the work precisely defining metric units and defined imperial in terms of metric.

        So now a foot is officially the precise distance light travels in some number of hyperfine structure transitions of caesium-133, and the US government didn’t need to do a thing.