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Comment: Re:(tsk tsk tsk) The poor puddy tat... (Score 1) 179

by Plazmid (#45849725) Attached to: Ford Will Demo Solar-Charged Car At CES

So the question we all want to know is can this actually happen?

Will a bird/cat/rodent be fried when they enter the beam?

Well we know the car roof has an area of 1.5 square meters and the lens provides 10 times the energy that would fall on the car roof. Using standard insolation of 1000 watts/m^2, we can deduce that the solar radiation flux on the car after the lens is 10000 watts/m^2.

So is this enough to fry a cat? The answer is.... yes, but it wouldn't happen instantly! According to wolfram alpha 10000 watts/m^2 is 10 times the radiation flux necessary to cause harm to biological tissue!

This is also in the range to singe holes in black pieces of paper!

Worst case, our poor puddy cat will probably make it out with some singed fur, but should otherwise be all right!

Comment: Re:Apples and oranges. (Score 2) 248

by Plazmid (#45440835) Attached to: Hotel Tycoon Seeks Property Rights On the Moon

Well, we have plenty of technologies for dealing with highly abrasive materials and operating in highly abrasive environments.

Take for instance the concrete pump, it's a device that moves a slurry of fine(and many times not so fine) particles at high rates of speed with a decent MTBF.

We have cars, trucks, and mining equipment that can operate with a decent MTBF in abrasive and sandy environments

We have helicopters that have to deal with operation in sand environments, where blades and other fast moving components essentially get sand blasted!

And there has been some recent work on lunar regolith tolerant connectors.

Now the bigger issue that we have isn't that the dust is abrasive, but that we can't model how the dust behaves! Granular materials like lunar regolith do not have scaling laws. Thus, we can't make small scale 'wind tunnel tests' on systems that handle granular materials, the only way to test is at full scale.

So when someone wants to build a new type of concrete plant, they test it out at near full scale and tweak it until it works, because we have no good way to computationally model it before hand. And even then, most concrete plants and other systems that handle granular materials do not work very well. They tend to experience jams and other problems which must be fixed with regular maintenance.

And we don't know why they jam or even in some cases why they work in the first place!

Thus we'd have trouble building a 'concrete plant' on the Moon without impractically large expenses, because we don't understand dust.

Comment: Re:Now this sounds like a perfect job for (Score 1) 248

by Plazmid (#45440649) Attached to: Hotel Tycoon Seeks Property Rights On the Moon

That is not a lot of water. 600 million cubic meters is roughly the volume of Sydney harbor. In human terms, this is certainly quite a bit of water, however, this water is spread out over a very large area. This makes getting sufficient amounts of water difficult, especially in cold, shadowed craters(no solar power!).

Comment: Re:No, he can't own the moon. He can take it thoug (Score 1) 248

by Plazmid (#45436837) Attached to: Hotel Tycoon Seeks Property Rights On the Moon

The Moon has no resources we don't have on Earth, however, it has them 'cheaper.'

Building a large structure in space like an orbital resort or a solar power satellite from materials sent from Earth would be impractically expensive. However, if one gets this material from the Moon, these sorts of structures become a lot more practical.

It is a lot less energetically intensive to launch a kilogram of something from the Moon(hard vacuum, low gravity) than it is to launch a kilogram of something from the Earth(air, high gravity). Just compare the Apollo Lunar Lander to a Proton rocket bound for the International Space Station.

Now as for mining the Moon as opposed to asteroids:
1. asteroids are typically quite a bit farther out than the Moon
2. the lunar environment is fairly well characterized: we have 382 kg of near pristine samples of lunar material, while we have only micrograms of samples of asteroidal material.
3.we know how to mine stuff in gravity, we currently do not know how to mine stuff in microgravity

Comment: Re:It's quite impractical, I'm afraid... (Score 2) 248

by Plazmid (#45436269) Attached to: Hotel Tycoon Seeks Property Rights On the Moon

Making something dust tight in a vacuum environment can't be all that hard. We have standards for preventing dust intrusion and they aren't all that different from standards for preventing water intrusion.

And we do have a way to clean dust off equipment in a hard vacuum. Moon dust easily picks up an electrostatic charge, allowing one to use an alternating electric field to remove regolith from solar panels.

The same technology, shouldn't be all that hard to integrate into space suits or other equipment.

Comment: Re:It not logical Captain (Score 1) 466

by Plazmid (#45167237) Attached to: Redesigned Seats Let Airlines Squeeze In More Passengers

Given that the average body weight in the United States is 164 pounds and we have 6 passengers, we have an added weight of 984 pounds. Less than the 1200 pounds saved. This does not take into account the weight of luggage however.

Now ideally one would have the passengers pay according to their weight at takeoff, but I'm sure many people would find this unacceptable.

There is no such thing as negligible weight on an aircraft.

If bankers can count, how come they have eight windows and only four tellers?