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by bencompanion 2859 days ago
Thank you - this article is interesting meat wrapped in lie-pastry.

The "will" in the title is just flat wrong. "Might possibly" is a stretch, even. People are sketching out the idea, enough that there are known but currently insurmountable problems in doing it. It's an interesting and promising approach in general though.

Some additional highlights:

> accelerate the nanocraft with a 60,000-G force

We're going to make a package of sensors, transmitters, power source and sail that weighs one gram and can also survive 60,000g's of acceleration for multiple minutes? For comparison, the US Navy's ship mounted railguns accelerate projectiles at something like 15,000-20,000g, and those are 10kg of high-precision tungsten, and need to do nothing except not disintegrate.

> The combined laser power needs to be something close to 100 gigawatts

If my maths are right, that's nearly the generation capacity of Japan (https://en.wikipedia.org/wiki/List_of_countries_by_electrici...). Granted, it wouldn't be required for long, but recruiting (or alternatively, storing) a whole-extra-Japan's worth of energy for even a few seconds is just completely ridiculous. We would need large-scale orbiting solar or commodity fusion power before we could even dream of anything like that.

1 comments

A normal tank gun is 30,000 g and electronic fuzes work just fine for those.
Is that right? I assumed a railgun's acceleration would be about as high as we can go. Huh! In any case, anything that we accelerate like that is highly durable and rigid - you can imagine what happens if you accelerate one part of a 'soft projectile' at 60,000g and another part at 59995g.
Not much? Most things can easily withstand a 5g delta.
Most things like rigid metals or strong plastics, sure. Things like hair-thin strands of carbon fibre mesh and thin plastic films? Not so much.