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FCC approves test of space mirror to light night sky

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Re: FCC approves test of space mirror to light night sky

#61
post #24

Wonder what would happen if a hacker focused all ten thousand of them on a single area for an hour or two. Sounds like a really energy-efficient way to demolish a city. X Wing: Wedge’s Gamble (1996) by Michael Stackpole shows the rebel alliance using similar tricks during the battle of Coruscant.

Die Another Day (2003) has a more ridiculous take on the same idea.

Re: FCC approves test of space mirror to light night sky

#62
post #24

Wonder what would happen if a hacker focused all ten thousand of them on a single area for an hour or two. Sounds like a really energy-efficient way to demolish a city. X Wing: Wedge’s Gamble (1996) by Michael Stackpole shows the rebel alliance using similar tricks during the battle of Coruscant.

> "Wonder what would happen if a hacker focused all ten thousand of them on a single area for an hour or two. Sounds like a really energy-efficient way to demolish a city." I'm far more concerned about the people who own/build stuff like this using it as you suggest (or any of the government pets that they own) than I am about "hackers" doin' such things (although, you're entirely right to have that concern as well,…

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Re: FCC approves test of space mirror to light night sky

#63
post #59
post #24

Wonder what would happen if a hacker focused all ten thousand of them on a single area for an hour or two. Sounds like a really energy-efficient way to demolish a city. X Wing: Wedge’s Gamble (1996) by Michael Stackpole shows the rebel alliance using similar tricks during the battle of Coruscant.

I don't think 50000 60-ft mirrors at the height they intend to fly would cause that to happen. Not enough light gathering power. 50000 60-ft mirrors is about the same area as a single mirror 2.5 miles across. So the area of the mirrors is about the area of a city. You gather as much light as the city itself in regular daytime. If you focused all of that perfectly efficiently onto a city, that city would just look lik…

[deleted]

Re: FCC approves test of space mirror to light night sky

#64
post #31

Earlier quoted context omitted.

Think of the military benefits.

Yes, think about how this can be weaponized. Illuminate an area? Or, focus that energy on a single point and you've got sun powered space lasers?

Except if the reflectors are shaped for wide area illumination, then their focal distance is probably nowhere near the distance from the satellites to the earth’s surface. So I don’t think is any “single point” to be had.

Heck, I haven’t done the math or anything but I bet even if you did instead use parabolic reflectors that were tuned to focus at the earth’s surface, it would still be very difficult to keep them aimed at a specific point for long enough to achieve significant heating. I wouldn’t be surprised if it’s difficult to achieve an increase in heating that’s close to, say, the heating difference from standing outside at noon as opposed to 5PM. Which then doesn’t do much because you couldn’t effectively use a reflector at noon, anyway. You’d want a lens instead. Or some sort of complicated Newtonian telescope type contraption.

Re: FCC approves test of space mirror to light night sky

#67
post #25
post #10

They seem to be talking about each satellite managing the luminosity of the full moon over a few square kilometres, and getting a few tens of thousands of them. Even if you ignoring how much drag these must have, and hence how much electrical power you'd need for an ion drive just to keep them up, each spot being a few km across (and only getting light while the satellite is over your horizon) is just not compelling.…

With global warming, trillions upon trillions of acres of immensely fertile bogland, in Northern Canada is thawing. The problem is, global warming doesn't affect daylight. 4 hours of "the sun barely makes it over the horizon" means no crops, no matter if the temp is above 0C in September. Obviously this satellite isn't viable, but all things start small. Large tracts of land could be illuminated. But of course, I que…

Though I have to ask the value of illuminating large tracts of mostly uninhabited land. Lighting areas where no humans are around to want the light seems like a proposition that’s mostly useful for further disturbing nocturnal wildlife.

What might be more useful is to illuminate just the areas where a human currently needs to see well. It would hypothetically be both more useful - you can concentrate more light in just the areas you need it - and less expensive.

What would be particularly cool about this hypothetical technology is that it could work equally well under foliage and indoors.

Re: FCC approves test of space mirror to light night sky

#68
post #25
post #10

They seem to be talking about each satellite managing the luminosity of the full moon over a few square kilometres, and getting a few tens of thousands of them. Even if you ignoring how much drag these must have, and hence how much electrical power you'd need for an ion drive just to keep them up, each spot being a few km across (and only getting light while the satellite is over your horizon) is just not compelling.…

With global warming, trillions upon trillions of acres of immensely fertile bogland, in Northern Canada is thawing. The problem is, global warming doesn't affect daylight. 4 hours of "the sun barely makes it over the horizon" means no crops, no matter if the temp is above 0C in September. Obviously this satellite isn't viable, but all things start small. Large tracts of land could be illuminated. But of course, I que…

If sattelites can reflect enough light to make an impact on e.g. global warming, they can also reflect enough to circumvent it. Point them back at the sun or into space and in theory it redirects the same amount of energy away from the earth as it would pointing towards it.

That said, I'm (armchair) confident it'll be good for moonlight-level illumination on a local area at best. They'll need to scale up to thousands / tens of thousands to make any measurable impact - which is their objective by the looks of it, but it'll take a while yet. If this one creates enough backlash, a fleet won't make it. Assuming they get the money and customers to justify a fleet in the first place.

Re: FCC approves test of space mirror to light night sky

#69
post #10

They seem to be talking about each satellite managing the luminosity of the full moon over a few square kilometres, and getting a few tens of thousands of them. Even if you ignoring how much drag these must have, and hence how much electrical power you'd need for an ion drive just to keep them up, each spot being a few km across (and only getting light while the satellite is over your horizon) is just not compelling.…

In regards to people with reasons to illuminate several sq km at once - I'd bet that major metro areas would see a massive savings in electricity/maintenance if these were deployed over a metro region. Whether that is more than the cost of a satellite? Who knows, it's still fiction until these people try it out. But it's at least an interesting use case.
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