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Comment by benp84 | Hacker News Reader

"can generate a magnetic dipole field at a level of perhaps 1 or 2 Tesla (or 10,000 to 20,000 Gauss)"

I'm just amused by this conversion. Who is this for? Are there people who know one unit of magnetic flux and not the other?

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It is probably for the "non-scientific" reader who thinks "1 Tesla seems very low to me, that's not really impressive. Now 10.000 Gauss: I can imagine that to be pretty ... much"

I'm not sure, but everyone in atomic physics talks gauss for some reason.

Well think about it... 1 Tesla = 10,000 Gauss. When you're talking about magnetic fields in MRI coils, or planetary magnetosphere it helps to use a larger scale. When you're talking about EM forces on the scale on an atomic nucleus though, it's more helpful to speak in terms of Gauss.

But that is why we have metric prefixes, different scales call for the appropriate prefix. Magnetic field of a neutron star ~1MT, magnetic field of a human brain ~1pT

Sure, but when you actually have to do math with them, and use them every day in practical language, it starts to make a lot less sense. After all, the goal of terms of art isn't to make the language of a given pursuit less opaque to "outsiders", but to facilitate work within the pursuit.

Who is this for? The kind of person who doesn't stop to consider how much energy it would take to run this hypothetical device, and what that energy/money/resources could do on Earth. "The common clay of the new West..."

Yes, there is that. But it's also rather like off-site backup. Or at least, somewhat off-site.

Edit: Anyway, I do agree that the priority ought to be displacing carbon emissions, and removing CO2 from the atmosphere.

Yes, but if you have zettawatts of energy to pump into a space station, you probably don't need to be doing something so crude.

They'd be using local PV for the field. With PV at that scale, they'd need to beam it back to Earth. And that could be quite the weapon system.

Sure, but you'd be talking about a civilization that could afford to build it, and operate it... a civilization so advanced that they can afford more than double our current energy production just to electromagnetically shield Mars.

I saw estimates here that 10% of current US energy use would suffice to start. And this would be entirely automated, using methods not that different from JWST, except in scale. And arguably, it's less complicated than beaming energy back to Earth. But still, those could be parallel efforts.

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