• not_woody_shaw@lemmy.world
    link
    fedilink
    English
    arrow-up
    5
    ·
    25 days ago

    It’s a room made from platinum-iridium, and kept in a triple-locked vault at the International Bureau of Weights and Measures in France.

    • cartoon meme dog@lemm.ee
      link
      fedilink
      English
      arrow-up
      3
      ·
      25 days ago

      unfortunately, opening the door changes the temperature, so in practice instruments are calibrated from copies of the room built at other metrology institutions around the world.