Comment on Startup Says It'll Use Huge Space Mirror to Sell Sunlight During Nighttime
echodot@feddit.uk 1 week agoVery temporary. If it’s onto light is small it has to be close to the Earth or no one will see it. But if it’s close to the Earth it moves so fast there’s no point, orbital speed for that altitude is something like 7.8 km per second.
The only way to make this work is to have a truly vast mirror and have it out at geostationary orbit, then angle the mirror as needed to turn on or off the sun but then you’re going to be covering a significant area of the planet.
To demonstrate how utterly insane this idea is, this is the sort of thing a civilization would do if it decided it wanted to terraform Mars. Doing this wouldn’t be the efforts of a single corporation it would have to be a global effort, we don’t currently have the capability of putting something that massive in orbit, we don’t have a way to reliably control the mirror, we can’t even manufacture a mirrored surface that large, and there have been zero studies on the environmental effects of doing this. It would honestly probably be easier to build a space elevator.
Oh and even if we did do all of this, despite it being impossible, it would only work for a couple of years and then the mirror would get pushed out of orbit by light pressure. The only way to counter that is extremely complicated mirror geometries, and even more mirrors, making the total surface area in the hundreds or even thousands of kilometer range.
Jimmyeatsausage@lemmy.world 1 week ago
It does sound ludicrous…might be better off making a concave mirror so it reflects and intensifies the light…like a giant magnifying glass over an ant hill. Yeah…that’s how they should do it. Nothing gonna wrong with that.
echodot@feddit.uk 1 week ago
A concave mirror would focus all of the light from a wide area into a single point. What you’ve created there is a giant space laser. One that only works at night because you need the sun on the opposite side of the Earth to reflect it.
Also all of the previous problems about it needing to be massive, or close to the Earth and moving faster apply.
KonalaKoala@lemmy.world 1 week ago
Yeah, what you just stated about a concave mirror is not only ludicrous, but would be very destructive to the wilderness and wildlife and probably would be time to contact every wilderness and wildlife defense group to have this so called start-up shut down.