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[Sheb]

Remember that you also probably have to build your huge laser on the Moon, because on Earth the atmospheric diffraction would be too much, and in orbit it would keep deorbiting itself because it actually generates thrust, and you would have to provide it with engines to compensate.

Wouldn't the thrust be minute? The reason those tiny craft accelerate so much is that their weigh would be on the order of a gram. A huge-ass laser wouldn't bulge much from the same energy.

[Antioch]

So how do you prevent such a craft from overheating? Wouldn't the vast majority of energy be converted into heat, even with reflective surfaces?

I mean, there is a reason they use lasers to shoot down shit out of the air now.

[Aklyon]

Well, presumably you're aiming at the sail, not the craft. Not sure past that however.

[Sheb]

So how do you prevent such a craft from overheating? Wouldn't the vast majority of energy be converted into heat, even with reflective surfaces?

I mean, there is a reason they use lasers to shoot down shit out of the air now.

AFAIK, just by using special sci-fi hyperreflective surfaces.

[Antioch]

So how do you prevent such a craft from overheating? Wouldn't the vast majority of energy be converted into heat, even with reflective surfaces?

I mean, there is a reason they use lasers to shoot down shit out of the air now.

AFAIK, just by using special sci-fi hyperreflective surfaces.

Can they use the same stuff to prevent missiles from being shot down?

[Avis-Mergulus]

Remember that you also probably have to build your huge laser on the Moon, because on Earth the atmospheric diffraction would be too much, and in orbit it would keep deorbiting itself because it actually generates thrust, and you would have to provide it with engines to compensate.

Wouldn't the thrust be minute? The reason those tiny craft accelerate so much is that their weigh would be on the order of a gram. A huge-ass laser wouldn't bulge much from the same energy.

True, I guess. It would still have to have engines to correct itself every once in a while.

So how do you prevent such a craft from overheating? Wouldn't the vast majority of energy be converted into heat, even with reflective surfaces?

I mean, there is a reason they use lasers to shoot down shit out of the air now.

AFAIK, just by using special sci-fi hyperreflective surfaces.

Can they use the same stuff to prevent missiles from being shot down?

With lasers, sure.

[Cryxis, Prince of Doom]

Wouldn't it also become more difficult to keep the beam from umm I don't know the proper word, spreading as the sails get farther away? Because don't lasers umm expand over a distance? Or is that just for weak ones like what you can buy at grocery stores (laser pointers)?

[TheBiggerFish]

Attenuation/attenuate.

No, that requires an atmosphere.

[TD1]

Plus, so long as you give it enough initial momentum, you don't need a continuous beam.

[Sheb]

Yeah, I think the plan is to accelerate them to 0.2c over a few minutes between here and Mars, and then let them coast to Alpha centauru

[Cryxis, Prince of Doom]

Attenuation/attenuate.

No, that requires an atmosphere.

But don't you have to fire the lasers from a surface station/base? Or are they setting up a satelite/deep space rig to do that?

[Aklyon]

The plan is to fire from earth, yes. So they're probably working on the attenuation problem at the same time.

[Cryxis, Prince of Doom]

I would have know the answer to that question a year ago but I have forgotten

[Baffler]

I don't know that it has a special name. I think you'd just call it the structural region or the regulatory region or whatever's applicable, or by the specific name of the region/subunit if it has one, but maybe someone else knows better.

[Sheb]

What's the name of the part of an enzyme that's NOT the active site?

The part that basically gives the enzyme structure?

Well, the active site can also give it structure. I don't think there is a specific name for "all the enzyme except that tiny part that does the reaction". Usually you're interested in referring to a smaller part.