Orbiting Brain Lasers!

[elfs]

The Japanese have announced that they're putting an orbital space maser up in the next decade. A maser is a laser that transmits microwaves. The idea is that the orbital station will collect solar energy and convert it to a maser form, which will then be beamed down to a collection station and converted to electricity.

What happens when the ray gets off course? The Japanese will tell you that can't happen; the beam will shut down if it strays, but what if it does? Well, if it's aimed at a city, here's what happens: everyone within the radius of the beam will first feel very hot, and a clicking noise will happen in their ears. The liquid in the ears is highly susceptible to microwaves. The feeling of heat will rise, but there will be little pain. Then they'll go blind as the soft liquids in their eyeballs, a liquid highly exposed to the environment, solidifies like egg yolk. Finally, the pain will reach your brain centers shortly before your knees and elbows explode in blasts of steam and you collapse to the ground, your bone-shielded brain finally registering the damage done before it too ruptures.

Comments

[oldhans117.livejournal.com]

But a tin foil hat would block the rays right?

[dossy.livejournal.com]

+1.

[autopope.livejournal.com]

I am assured that the beam will be designed to spread, so that for, e.g., a 1km^2 solar array, the beam at ground level will cover around 5-10km^2. So, no exploding eyeballs.

Advantage over ground-based solar: in principle you can keep an orbital solar power station out of earth's shadow, so enjoy solar power 24x7. Oh, and you get 4-5 times the energy per unit area of solar collector in orbit that you get on the ground (due to atmospheric losses). Downside: fiendishly expensive to build.

Of course, this assumes the orbital maser is designed with purely civilian applications in mind.

What could possibly go wrong?

[nojay.livejournal.com]

Atmospheric losses of the light spectrum are in the region of 20-30% on clear days, not 400%. There will be corresponding losses in the maser beam due to airpath absorption too, although the beam's frequency will be selected with that in mind to minimise the global warming effect. There are other constraints on frequency such as transmission antenna size and geometry, plus losses in the up-conversion from solar cell electricity to maser energy -- getting rid of waste heat in the satellite could be a serious design obstacle.

As for that minor problem about having your brain boiled in your skull and your knees exploding? You've been in Akiba during August, just like me. Par for the course.

[tehrasha.livejournal.com]

The frequency selected is more likely chosen for efficiency of conversion at the receiver than preventing global warming. Any atmospheric warming done by the beam would be seen as a loss of efficiency and likely avoided for that reason alone.

In the end, we will still end up with more energy reaching the earth than would normally, and no matter how it is used, emitting heat.

[kengr]

Also, and much more important from a global warming standpoint the inefficiencies of "generating" the power (ie waste heat at the "generator") will be in *orbit, not on the ground.

Assuming 30% efficiency, that means that you'll have 7 watts of heat in the solar cells for every 3 watts sent towards earth.

If the cells were on the ground, those 7 watts would contribute to global warming. In orbit, they are just something you have to add bigger radiator surfaces to the satellite for.

[lemur123.livejournal.com]

The major concern regarding global warming is the energy required to get that mass into orbit. Unless you're using lunar or asteroid raw materials and manufacturing the array in-situ, the amount of energy consumed in the earth's atmosphere to get the parts up there is around 5x10^9 J/kg (yes, I know that's optimistic, but let's assume they're using something more fuel-efficient than what we have today). Or about the equivalent of burning one tonne of gasoline for every kilogram of solar array. They'd have to offset a lot of in-atmosphere emissions to make up for that.

[darrelx.livejournal.com]

Any heat energy emitted by solar panels at ground level would have been absorbed at ground level whether or not solar panels were present. Solar panels do not contribute to global warming.

The only way an orbiting solar array would help keep the planet from warming is if it cast a shadow on the earth. The cooling effect of said shadow, however, would be offset by the energy loss of microwave energy travelling through (and heating) the atmosphere.

Most science I've seen on this subject says that orbiting solar collectors aren't an advantage at all. This will be a large experiment which I predict, will prove that this alternative energy source is economically non-feasible.

It may, however, prove to be useful sometime in the future for weather control or military applications... but that assumes that those applications have enough political support to stand.

Hmm

[ideaphile.livejournal.com]

The "4-5 times" figure more likely comes from the fact that solar panels at ground level collect, at best, 20%-25% of the energy that is theoretically available from the Sun at the distance of Earth's orbit-- that is, you'll find that for each watt of peak capacity, a solar panel will produce around 4 to 5 watt-hours of electricity per day on average. The same watt in orbit can produce much closer to 24 watt-hours per day, since it can be kept perfectly square to the sun, the sun is almost always visible, and there's no atmosphere or dirt in the way.

But solar cells are still inefficient, and there are more inefficiencies due to conversion to and from microwaves and sending the power from the big unpopulated area where the collector is located to the populated areas where the power is to be consumed.

Whether this whole idea pans out or not is still uncertain. It isn't at all clear to me if solar power satellites can pay off given the high costs of getting the hardware to orbit, the lawyer-bait nature of the microwave downlink, and so on.

But I'm happy to hear that someone's working on it.

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ORLY

[ideaphile.livejournal.com]

What kind of power density are you assuming there, Elf?

All I can tell from the Japanese web page describing the program is that the size of the receiving antenna is about 100 km^2 for 1 GW of power, or around 10 watts per square meter, which is about 1% of the power in sunlight on a hot day.

Similarly, what figures are you assuming for the absorption of the 5.8GHz energy in biological tissue?

I can't find any easy answers for how sensitive we are to 5.8 GHz energy in particular, but cellphones are allowed to heat our tissues at a rate up to 1.6 watts per kilogram, and I didn't notice any perceptible heating, ear-clicking, blinding, pain, or joints exploding in blasts of steam even in the days of analog bag phones that could transmit at up to 3W effective radiated power (ERP) or handheld phones rated at up to 600 mW ERP.

So I call BS.

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Re: ORLY

[gromm.livejournal.com]

Yeah, I was thinking the same thing. The exact frequency used in microwave ovens wouldn't be used for these masers, in no small part because we're not interested in evaporating any clouds that get in the way - they'd greatly reduce the efficiency of the system. As a result, we won't be using the frequency required to vaporize water in animals, either.

Turn In Your Geek Cards!

[ionotter.livejournal.com]

Look at all these geek-poseurs, arguing over power densities and whether or not it would really happen!

That's NOT how you're supposed to react to news like this?

The correct response is: AWESOOOOMMME!

[http://users.livejournal.com/_candide_/]

Ok, Elf, first: shame on you for propagating the myth of, "Microwaves == nuke-you-lar == OMG!We'reAllGonnaDieFromTheDemonDeathRays *muppet-arm-flailing*"

Second: as others already stated, beating me to it: The "colors of microwave-light" that would do what you just described are the ones that water absorbs. But there's also water in the air, y'know. So, wouldn't we want to design the transmitter so that it transmits "colors of microwave-light" that water's transparent to?
And if the power's being beamed down in a form that passes through water like visible light through glass, how, exactly, could a body absorb it?


Third: In addition to tuning the transmission maser to a frequency not absorbed by the atmosphere, wouldn't we also want to pick a frequency that isn't absorbed by other common organic compounds? I'd think that the engineers designing this system would do just that. Y'know, just to be on the safe side.


Mind you: I'm not saying that such a transparent-to-organics-and-H2O maser would be harmless if it hit something living, not at the intensities used here. But making you asplode? No, no I don't think so.