California-based startup Reflect Orbital aims to build a swarm of 4,000 giant mirrors in low Earth orbit to “sell sunlight” to customers at night. Experts warn that the mirrors could mess with telescopes, blind stargazers and impact the environment.
Reflect Orbital, which was founded in 2021, has recently taken the first step in a scheme to sell sunlight at night by bouncing solar rays off giant “reflectors” that can redirect the vital resource almost anywhere on our planet. By doing this, the company aims to extend daylight hours in specific locations, thus allowing paying customers to generate solar power, grow crops and replace urban lighting.
But experts say it is a wildly impractical plan that should never get off the ground. What’s more, the resulting light pollution could devastate ground-based astronomy, distract aircraft pilots and even blind stargazers.
Why are all the experts going on about the fact you might blind pilots but not talking about the fact that it won’t actually do anything.
It would have to be an astonishingly vast megastructure for it to have any effect at all. If we were talking about a structure 100 km across or more they might actually have some sort of point.
No.
for solar, a 5km diameter solar farm might hold 10m square meters of panels. at 250w each, 2.5gw solar farm. 4 times a full moon, is 1/100000th the rated capacity (noon at equator) of panels, and so 25kw of power. At 10c/kwh electricity revenue potential, such a farm (exists only in China) could break even offering to rent night light at $2.50/hour.
Batteries charged by solar can deliver profitable electricity at night for far less than 10c/kwh.
If you just want more light somewhere, it would be far cheaper to do from ground systems.
Joking aside this is a horrible idea even if it were possible to get right. Anything with circadian rhythm is going to get fucked up real fast and that includes people. This is like angry mob outside the corporate office level bad. Torches and pitchforks, the whole thing
So literal space lasers?
This isn’t even possible and the cost even if it was would be ASTRONOMICAL.
I almost wish this was not a practical impossibility just so we could get to see the headlines when some misalignment fries an island of billionaires like bacon.
All of these wacky silicon valley startups popping up just shriek very loudly that there is too much capital and not enough real economy to invest all that money into.
Because they’ve destroyed the economy
Why is this not an Onion piece???
You don’t even have to be an expert to see that this is one of the stupidest ideas ever conceived.
If we could actually do this, couldn’t we also send up large Sun ray blockers that would help us control global warming?
how is that profitable? they won’t do it unless they can make money.
Throw these guys in a volcano. Add the billionaires and tech capitalists while at it.
“We’re a startup”
“What’s your plan?”
“Giant mirrors in space to control the sunlight that hits the earth’s surface.”
“Wow, sounds incredibly expensive and of dubious technical merit. What are you asking to make this happen?”
“We need whatever money you have in your wallet right now.”
“And the return on investment?”
“Infinity zillion dollars.”
“I guess I’d be a fool not to hand you all my money.”
“Absolutely. Now… that’s a really nice watch. And shoes. We could get you an amazing return if you gave us those, too.”
In addition to being a moronic idea, this is also physically infeasible as I outlined in excruciating detail in my comment the last time this came up. The takeaway is that this is an investor scam for sure, and the side effects outlined in this article are just a fun (!) and exciting (!) sideshow if these bozos actually do mange to get a single mirror off the ground and deployed. Which they probably won’t.
I disagree they are bozos. I’m actually coming around on the idea. Not the mirror thing of course, but the VC grift using a flashy idea. Millions of dollars and the only thing you make is a slideshow? Brilliant.
It’s tricky business. The idea has to be plausible enough to attract investors, but implausible enough not to get looked at too closely by clever investors. Similarly, you have to drum up enough publicity to get interest, but not enough to get scrutiny.
Get the balance wrong and you get Theranos.
I’m gonna start a startup called startup starter and my business plan will be selling business plans to startups that are flashy enough to attract VC money so you can siphon off as much as possible before the business folds.
I’d like to see that comment if you could link it!
I mean just on the surface of it, this is completely preposterous.
The first thing that comes to mind is you can only cover so much area. 4000 satellites would cover the dog park near me. In the scope of an undertaking like this, it’s a trivial amount of energy they could possibly gather?
That’s the main hurdle.
Re-finding this was a pain in the ass because I didn’t save it. https://lemmy.world/post/19485246/12219336
Editing to add some more meandering. Now this is even longer than the first one.
In addition to surface area limitations, there’s also a pretty obvious line of sight problem in that if your satellite is positioned such that its shiny side is facing the sun, by definition it must be facing the same direction as the Earth’s currently lighted side. The further past the dusk line onto the dark side of the Earth you’re trying to hit the further you have to rotate your mirror until ultimately the surface of it is perpendicular to the incoming sunlight. This is the angle of incidence, in optical terms, and it reduces the effective reflection not only off of the mirror proportionally to the increase in angle (in a roughly geometric manner, I believe) but also where that reflected beam of light hits the ground at its oblique angle. In real terms, it will be impossible to hit any target more than a few degrees past the dusk line with any meaningful amount of energy. Insofar as this harebrained scheme could possibly hit the ground with any amount of energy at all.
The diagram (which is surely not to scale) on these idiots’ website seems to depict a mirror in orbit around the Earth that’s about the size of Massachusetts, which is orbiting at a height that’d put it somewhere in the vicinity of the Van Allen belt, which is also a bad idea (no radio communication for you!) and would result in an orbital period of around 2.5 hours. If so, that means your mirror is whizzing over the surface at something like 14,000 MPH, and you would have some kind of line of sight to it from the ground for maybe 25% of its orbit. So even with the best will in the world and absolutely mathematically perfect rotation control it’ll only be able to remain on a surface target for about 37 minutes at most, most of which would be while it’s uselessly passing through the Earth’s shadow and is reflecting no sunlight at all, and for the remaining handful of minutes with its effective output tapering off to uselessness as it sets over the opposite horizon.
“I’ll just position my mirrors in a geostationary orbit,” says Mr. Clever. “Then I’ll have line of sight to a big chunk of the surface and my satellite won’t move relative to it.”
Well, the further you park your mirrors from the surface, the harder they are to aim. You can’t have it both ways. A geostationary orbit is about 22,000 miles from the surface, a distance from which even the tiniest error in alignment will result in you hitting the wrong target. You can use some middle school trig to calculate this for yourself: At a distance of 22,000 miles, an alignment error of just 0.01 degrees will result in the centerline of your beam missing the target by four miles, which in terrestrial terms is what we refer to as kind of a lot. Maintaining an alignment precision that high especially taking into account gravitational perturbation by the moon, etc., is a rather tall order. To maintain targeting precision within 223 feet, which is probably already unacceptable, you need a constant alignment precision of 0.0001 degrees, and you need to hold it there 100% of the time.
I don’t care how big your rocket is, that’s not happening.
All of this also assumes perfectly flat and 100% reflective surfaces on the mirrors, which never degrades or gets scuffed up or punctured by space debris. Which is also impossible.
To recap:
- You can’t reflect any more energy than strikes the surface area of your mirrors, end of story. The mirrors will be tiny, relative to the size of the Earth, and the Earth is huge, relative to the size of any mirror we can launch.
- The efficacy of your mirrors diminishes geometrically with how far you must angle them relative to the direction of incoming sunlight.
- Most of the time your mirrors will either be in the Earth’s shadow, where they are useless, or over the already illuminated side of the Earth, where they’re pointless. In easily achievable low Earth orbits, their time on target will be very short.
- Positioning the orbits high enough to mitigate either problem will make aiming mathematically impossible, and also magnify any imperfections in focus, which are certain to be vast. That won’t work either.
TL;DR: The whole thing won’t work.
Thanks for the write up!
I’m curious how strong an effect atmospheric scattering would have, even after all that
Yeah this is another rugpull meant to allow the rich to get richer on the money of idiots
