• Hedgehog@lemmy.blahaj.zone
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    1 year ago

    Turns out it’d be a dissapointingly small sphere:

    US annual defence budget = $800 billion

    2% = $16 billion

    Obsidian cost per kg = $5

    Total kg in budget = 3.2 billion kg

    Density of obsidian = 2.6 g/cm3 = 2600 kg/m3

    Total volume of sphere = 3.2b/2600 = 1230769 m3

    Volume of sphere = 4/3 π r^3

    Radius = (3V/4π)^(1/3) = 66.48 m

    The sphere would only stand at 133m tall, I propose we instead utilise the entire defence budget for a much more skyscraper like 490m tall orb

    • Margot Robbie@lemmy.world
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      1 year ago

      Nobody said it had to be a solid sphere, how else would you get it to emit the ominous hum without attuning its natural frequency by carefully designing the thickness of the obsidian layer?

    • lseif@sopuli.xyz
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      1 year ago

      ignores engineering and construction cost. but we can assume that all people involved would work for free, because its a massive honour

    • TheKracken@lemmy.world
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      1 year ago

      You’re assuming one year of budget. I take it as 2% per year and something of that size would likely take 10+ years to build out.