• phutatorius@lemmy.zip
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    2 days ago

    I’m not sure how well a faraday cage would protect against something like this. Maybe a lot maybe not as much as you’d think.

    Very effectively.

    The Carrington event was caused by a coronal mass ejection (CME), not a solar flare.

    A coronal mass ejection is a cloud of charged particles (plasma) emitted by the sun. When it hits the earth, it induces a voltage in the earth’s magnetic field. North-south, there’s no voltage differential to speak of because that’s the orientation of the magnetic field’s lines of force. But on an east-west axis, there can be a large voltage differential. So if there’s a big-ass conductor oriented on an east-west axis (like the transcontinental copper telegraph lines at the time of the Carrington event), that conductor can carry a high voltage until it is discharged. The magnitude of that voltage is proportional to the east-west vector component of the length of the conductor.

    So, if a huge CME leaves the sun and is forecast to hit the earth, grid operators have 18 hours to a couple of days to decouple their grids along the east-west axis. 1/4 the length, 1/4 the induced voltage. That can make a big difference. And they know how to do that and have done it before.

    A lot of the freaking out about CMEs is based on cunfusion CME impacts with the effects of electromagnetic pulses (EMPs) which are superficially similar phenomena with different (manmade) causes. But CMEs are huge, diffuse, and not ultra-fast-moving, so they don’t hit like a spike as EMPs do, they hit more like an extended gust of wind, and the induced voltage doesn’t grow in microseconds, it grows over hours. So worrying about what’d happen to disconnected home electronics in the event of a CME is silly.

    There might be other problems, though, besides the grid induced voltage I’ve already mentioned. Satellites can accumulate static charge and malfunction, so you might lose GPS and some satellite-based communications paths. The earth’s ionosphere might be disrupted, interfering with HF radio communications and with radio communication that relies on ionospheric skips. But those are the biggest impacts.

    And if there’s an EMP, it’s likely that’s because someone set off a nuke, so the loss of your game controller is going to be one of the least of your worries.