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Could nanotechnology be used on the spaceship to make it's computer systems data processing more powerful? Could it also be used to make better computer chips on the trip to Mars?
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Yes, kind of. Nanotech for computing will make computers in general moer powerful. However, raw power isn't really that critical for space travel. Remember that we got to the moon using computers that are less powerful than today's wristwatches.
Technically speaking, nanotech has traditionally been associated with building structures under 100 nm in size. (this is a poor definition, nanotech is now generally associated with structures that show quantum confinement effects which occurs under 10 nm, generally and the 10-100nm size scale is now often referred to as mesoscopic) By the old definition, current semiconductor tech is now nanotech since it has feature sizes of 90 nm. Both Intel and AMD are already gearing up for the next jump to 65 mn. In the next 5 years, both companies are expected to get to 35 nm processes where the laws of physics finally wreck the party.
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Are you talking about what happens at the plank scale? They will probably deal with the problems when they get to below 35 nanometers. There will probably be a lot of problems with the chaos that happens at that size.
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The Plank scale is something entirely different - that's supposed to be the fundamental quantum unit of length, something like 10^-35 m or something like that. A Plank length to an atom is equivalent to an atom vs approximately 10% of the entire observable universe. Very small.
Quantum effects are something one tends to see at under 10 - 20 nm or so. One sees things like surface plasmon confinement effects on metal particles below about 20 nm in diameter. True 'quantum dot' effects kick in for semiconductors at 5-10 nm and for metals at 1-2 nm. Things like electron position uncertainty are only a problem below a couple of nanometers.
For example, part of the reason that chips run so hot these days is that there's a lot of current leakage from the transistor gates into the circuits. Presently, the SiO2 insulator seperating the gate from the rest of the transistor is less than 5 nm thick. The use of high K dielectrics for the gate insulator allows the ates to be made thicker again, lowering current leak but is probably boing to be the eventual show stopper for current microprocessor tech.
The real advance tha a lot of people mistake for nanotech is self assembly. The ideal way to buidla computer is like how living organisms assemble themselves - through tiny subunits that put themselves together. Unfortunately, our knowledge of how to do this is still very primitive.
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As far as building large spacecraft, computers aren't even a major mass contributor... The only advantage I can think of for building spaceships would be advanced nanocomposits, which would have even higher strength-per-weight as carbon composits, by building the nanostructures atom by atom... which at the moment isn't possible, and its a tossup if physics will permit it. This would especially be nice for fuel tanks.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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Also, many of the so called nanomaterials really don't need nanotech to be created. For example, carbon nanotube composites are made with furnaces. These nanotube composites won't get you a space elevator but will give you materials with a strength to weight ratio much higher than steel.
Diamond is also starting to become a possible building material. New vapor deposition techniques can grow a gem-sized diamond in a week or two. The process can be scaled up arbitrarily. Although large diamond structural elements would still be horribly expensive, it entirely possible that in 20 years we'll see spacecraft with diamond and nanotube construction that weigh 1/3 what a current craft does.
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What about amorphous metals? Will they be important building materials for future spacecraft?
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A silcon based amphorus metal could be made magmetic. Which could be used for a propellent, and could be made from asteroid material.
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Amorphous metals aren't a whole lot better than regular ones, and tend to break or snap more easily, their advantage is they can be "melted" more easily and molded.
Metals as reaction mass? That would have terrible ISP.
[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]
[i]The glass is at 50% of capacity[/i]
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The primary use of amorphous metals is in high temperature turbine blades. At the temperatures and speeds they operate at, the blades inevitably start stretching out like taffy and need to be replaced on a regular basis. Normal metals are composed of small crystallites that tend to stretch differently on the different axes. The internal stresses and defects that result can result in failure at the grain boundaries.
The two solutions are to either use single crystal blades where the entire blade is one big metal crystal or to use glassy amorphous metals where the whole thing is disordered and therefore doesn't have any crystalline boundaries in it. These days I think that amorphous metals are used more commonly because it's cheaper to make. Basically, you take molten metal, drop it onto a very rapidly spinning disk so that it's splattered into tiny droplets that then plunge into liquid helium. The cooling rate of millions of degrees a second prevent any crystal formation. The powder is them cold pressed into the final desired shape.
In contrast, single crystal metals are formed by taking a small seed piece of metal that's attached to the rest of the blade by a small channel that looks kind of like a pig's tail. The metal starts crystallizing on the seed as they progressvely cool the metal and the curlique channel causes all but one of the crystal grains to eventuall run into a channel wall and die out. The single crystal then grows out of the channel and into the die where the blade is sitting. Through very careful control of the temperature, you can ensure that the entire blade is a single crystal of metal - not easy to do.
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