Comment by Cthulhu_
14 days ago
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.
This is where people who think space access is only for satellites and LEO space stations have no imagination. We’re at a place now where if global warming did suddenly start to run away, within a year, we could realistically launch enough solar shades to meaningfully impact the situation. It’s far fetched, but this is why innovation in general is important. Not for what we know now, but for all the unknown ways it could be used in the future.
Right now we're still not close to that kind of capacity.
I suspect just painting all the rooftops and tarmac white will be about as effective as 2000 Starship launches filled with mylar sheets, plus an L1 delivery system because one thing you really don't want for a global warming mitigation is for them to fall out of LEO and burn up almost immediately from the huge drag-to-inertia ratio.
For those purposes, why would it need to be mirrors? We don't care to coherently reflect the light; we just want to block it.
(For reference, I think all of these are likely to be somewhere between moderately and incredibly bad ideas...)
> We don't care to coherently reflect the light; we just want to block it.
The energy has to go somewhere. If you're not reflecting it you're absorbing it and you eventually have to do something else with it.
In fairness, a white sheet and a mirrored sheet will have much the same impact in this regard.