Japanese Agency Plan for Robot Lunar Base

Dilaudid writes "According to these articles Keiji Tachikawa, head of the Japan Aerospace Exploration Agency sees a major role in the lunar base planned by NASA in 2020. 'As part of the plan Japan would use advanced robotic technologies to help build the moon base ... Japan's lunar robots would do work such as building telescopes and prospecting and mining for minerals, Tachikawa said.' Tachikawa was voted one of the 25 most influential global leaders by Time... I wish him luck!"

Re:Mineral extraction and Moon's mass?

[cens0r]

Easy answer no. Would you like me to show you the math?

Re:Theories (asinine)

[Gramie2]

Keiji Tachikawa's last name is the same as Tachikawa, a town outside of Tokyo, founded on December 1, 1940. Coincidence?

150 years ago, when common Japanese people were permitted to have surnames (in feudal Japan, only nobility were given the privilege), many of them took the name of the place where they lived, or just names that sounded good.

http://en.wikipedia.org/wiki/Japanese_name [wikipedia.org]

Coincidence? Hell yeah! Or is there some deep, possibly Zen meaning to December 1, 1940 of which I am not aware?

Re:Wow...

[Rei]

Not *nearly* so easy. Please read about every step (in detail) from raw silica to polycrystalline silicon here on Earth. Down here, first silica is mined and finely ground. It is then reacted with pure carbon under high heat (i.e., external power) in an electric arc furnace to produce silicon metal. Carbon is a trace element on the moon, by the way, so clearly this won't work there unless you keep a closed carbon cycle, which isn't easy at all.

Silicon metal isn't good enough, though. You take the hot metal from the furnace and react it with HCl (both trace elements on the moon) near a copper-containing catalyst to produce SiHCl3 (plus a number of other byproducts, which need to be separated out and either become waste or reused, which would involve another series of steps for each product). The SiHCl3 must be exceedingly pure, and reacted with exceedingly pure hydrogen gas at very high temperatures in clean-room conditions, before being allowed to cool and crystalize (electronics-grade silicon has less than 1 ppb impurities).

Of course, producing electronics grade polycrystalline silicon is itself not enough. You need n and p doped silicon produced and layered to create a boundary layer n-p junction. You then need microscopic contacts laid out on the surface at the micron-scale (i.e., it's almost like building a CPU plant on the moon) to carry off the charge to whatever is to consume it.

This in itself isn't enough, however. The delicate wafers need to be carefully layered onto a rigid surface (which you need to produce) and protected on the other side with a transparent material (the protective material needs to be produced). The whole assembly needs to be mounted at an optimal angle (preferably to a heliostat); whatever it is mounted to needs ot be produced. The entire arrangement needs to be wired (the wires need to be produced), and power brought to huge batteries (which need to be produced) to keep power through the two-week lunar night, after being run through transformers (which need to be produced).

Notice all of the "to be produced" items? Each "to be produced" has its own production chain which is not trivial.

Re:Mineral extraction and Moon's mass?

[cens0r]

F = (G * massEarth * massMoon) / d^2

G = 6.67x10^-11
massEarth = 5.9736x10^24 kg
massMoon = 7.349x10^22 kg
d = 3.844x10^8 m

F = 1.982x10^20 N

Now lets say we remove 1% of the moons mass.

massMoon = 7.27551x10^22 kg
massRemoved = 7.349x10^20 kg

If we use the F from the previous solution and solve for d:
d = 382437 km

That's an increase of 13 meters. I'm sure my rounding is off a little but that gives you an idea.

Now to change the orbit 13 meters we have to remove 7.349x10^20 kg of material from the moon. That is 810,000,000,000,000,000 tons of material. If you were to unload 1000 tons a day it would still take 2,220,000,000,000 years to take that much.

So my original answer of no stands. We have nothing to worry about.

Re:Theories (asinine)

[shmlco]

when in each case the war was essentially over

The Battle of Okinawa [globalsecurity.org] was one of the bloodiest of the Pacific, killed more people than Hiroshima and Nagasaki, and invasion of the Japanese homeland was projected to be at least 10 times worse.

While Hiroshima and Nagasaki were unfortunate, it prevented the need for an invasion that would have killed tens of thousands on both sides. In addition, a "public" target was choosen to illustrate to the Japanese people what would happen if their leaders failed to surrender.

Bombing an out-of-way military target would not have had the same effect, and could potentially be denied by the government.

What we "wanted" was to end the war, and to minimzie the number of our people that would have to die in the process. If such could be accomplished, AND a message sent to others at the same time discouraging further aggression, then all the better.