Live data from Hacker News

FCC approves test of space mirror to light night sky

theconversation.com

41–50 of 164 posts

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

#41

Earlier quoted context omitted.

Annoyingly and predictably, reads like AI slop. You can practically guess the prompt goes something along the lines of 'write a press release explaining why this bad idea is a good idea'.

Do you have anything to say about the project itself or do you only care about your perception of ai slop?

I swear this is getting so common. “Well I’d be fine with eugenics and sterilization of the poor, but the website uses em-dashes a lot so I think it’s just awful AI slop”.

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

#42
post #38
post #29

The only non-marginal application for this is military, surely. It sounds too coarse-grade in terms of its area to be anything other than disruptive socially and ecologically. Sporting and cultural events? Not really (extending the hours of sunlight over a city does have marginal value for a major celebratory event I suppose, but there just aren't that many of these). Farming? Don't plants need night too? Does harves…

Illuminating a solar farm for 24 hour power generation?

Is it possible it can deliver anywhere near enough solar energy to make this economically viable?

It's not going to be full daylight, is it?

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

#43
post #38
post #29

The only non-marginal application for this is military, surely. It sounds too coarse-grade in terms of its area to be anything other than disruptive socially and ecologically. Sporting and cultural events? Not really (extending the hours of sunlight over a city does have marginal value for a major celebratory event I suppose, but there just aren't that many of these). Farming? Don't plants need night too? Does harves…

Illuminating a solar farm for 24 hour power generation?

At the orbits they're talking about, at best 30 minutes before dawn and after sunset. Earth gets in the way, have to go much much higher to get 24 hour coverage, and if you can focus that well over that distance you've got the optics for a super-weapon.

And as this is optical, won't go through clouds. This is why beamed power discussions often talk about converting to microwaves instead, though that comes with an even bigger spot size on the ground.

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

#44
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…

[deleted]

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

#45
post #21

We've entered the "bond villain" era of VC startups

Someone tried to recruit me back in 2000 for a startup that would sell a box you connect to your computer allowing you to smell things over the internet. I'll let you guess what industry he was targeting.

Was it ... Musk?

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

#46
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…

Mars… needs something rather bigger. I don't know what the most cost-effective solution would be, but Mars gets about half the per-area sunlight as Earth so it would need a reflector about the size of Mars to get the same overall insolation.

My guess is it's probably easier to make a bunch of greenhouses on the surface? But the scale is so huge that which is best will be affected by technology invented after you start.

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

#47
post #15

How are the economics of this idea meant to be viable? The proposed business model is to park hundreds of millions to billion dollars of satellites in orbit, plus the costs to maintain and operate them, to meet the goal of selective area illumination and solar power. Ignoring the issue of cloud cover, which still seems to be an impediment. That's going to need to directly compete with terrestrial energy storage techn…

The revenue potential is huge. Think of public events where people might want to illuminate the area as daylight for several hours. Galas, sports, concerts, parties, etc.. They will all pay top dollar and they have the funds. Could get sponsors, "Today's sunlight brought to you by NordVPN"

Opposed to holding the event during the earth's orientation towards the sun, aka daytime? Someone should tell the gala and event organizers about this idea of daytime.

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

#49
post #20

Earlier quoted context omitted.

And also cheaper than launching stuff into space. This may have been approved but that's a long ways off from actual viability.

Launching a gossamer thin mirror in space is not very expensive. Broad strokes claiming anything launched to space is going to be a more expensive solution has to level with the fact that GPS and quite a lot of telecommunications and Earth observation seem to have incredible leverage if launched to space instead of just using ground based solutions.

For this use, "gossamer thin" is unlikely. You want to control where you point the mirror, it needs a structure that not only doesn't flop around when you torque your spacecraft, but also doesn't have surprise vibrational modes that squeeze and expand the illumination zone.

(Things I'm learning while researching what is now looking like an eight thousand or more word blog post about why a different space thing, data centres, is also not a good investment; my guess is this would be less of a problem if you used mirrors like this to cool the earth by reflecting sunlight away instead of towards).

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

#50
post #37
post #29

The only non-marginal application for this is military, surely. It sounds too coarse-grade in terms of its area to be anything other than disruptive socially and ecologically. Sporting and cultural events? Not really (extending the hours of sunlight over a city does have marginal value for a major celebratory event I suppose, but there just aren't that many of these). Farming? Don't plants need night too? Does harves…

> The only non-marginal application for this is military, surely. I think so, but even then it's a heck of a lot of work to make it useful for that. > Farming? Don't plants need night too? Does harvesting need the sun anymore? Mostly limited by other things, hence why there's only limited farming in the Sahara, relatively little phytoplankton in the North Atlantic Gyre. > But being able to illuminate a war zone with…

I guess it has policing applications, marginally. But most police forces just use helicopters and night vision, and ultimately rely on the disruptive sound of the helicopter to bring people out to look for whoever they are chasing; the noise of a helicopter makes people vigilant.

I just don't really get it.

Post reply on HN