Is the Concept of a Self-Replicating Unmanned Spacecraft Feasible?

[{~}]

I didn't know where to post this. It seems a bit week on science for the forums.

I had this idea in for a role playing group I am in on myspace. Anyways the story is that I am in charge of the martian space navy and this is supposedly our newest weapon to use against the "space Nazis." It is an unmanned spacecraft that can be driven into other spacecraft at very high speeds.

I want to know what you all think about the feasibility of this thing. We always try for realism and I think that is especially important whenever we step up the technology of our universe.

This is what I wrote

The navy has been working on a project for the last several years. I think we finally have a formidable weapon.

We call it the Black Wisp

These are the parts

• sail
• generator
• computer
• laser array
• nano factory

The sail is made out of stacked, unbroken layers of graphite. When the wisp needs to brake quickly it can eject the top layer of graphite and accelerate it away from itself using the laser array. It can also eject sail mass to use as a weapon.

The generator is an array of micro black holes. They are held to the grid by electric cages. The black holes are fed mass and charged particles so they stay at the same charge and mass. Micro black holes evaporate quickly. It is the way the black hole converts its mass, charge and spin into heat that makes them so useful to us. This is the first ever matter to energy drive.

The heat given off by the black holes is mostly in the form of incoherent light. This light is sent to the laser array. Light bouncing off the sail is what makes it go. Obviously propulsion is the most power intensive part of a spacecraft , especially one with this kind of acceleration ceiling (in the hundreds of gees).

The laser in and of themselves are only marginally effective as weapons, but they can be used in much more tactical ways. They are used for silent communication between two points. They can be used to paint targets for missiles or other spacecraft . They can used to map surfaces from a distance with a much better resolution than radar. Than can be used to determine relative motion by analyzing the Doppler shift. It can find gravitational anomalies using its very accurate range finding abilities. It can measure atmospheric conditions and predict the weather better than any weather satellite. It can probably do many other things as well, I just haven't thought them up yet.

The laser can also be pointed at other sails, to accelerate them as well.

The laser grid is connected to a photon computer. This computer is much faster and smaller than its silicon counterpart. It can also withstand ionizing radiation without like nothing was going on. Another advantage is that it is powered directly form the laser grid without electricity. The only time we need to convert light energy to electricity is to run the black hole cages. The computer pilots the wisp. It collects and analyzes data and makes tactical decisions. It communicates with the Martian navy the same way any other pilot would, through English text transmission.

The last part is the nano factory. It breaks down any chemically organic material that the sail might come into contact with. The carbon is used to replace sail material. Everything else goes to the black hole feeders. The nanotechnology is actually genetically modified bacteria that break down just about anything including long chain polymers (aka oil). The bacteria secrete a special enzyme that builds graphite. Other bacteria control the sail graphite construction process and are themselves controlled hormonally. There is a gland that produces the hormones and it is activated by the type of light emitted by the computer.

It is possible to coax a black hole to produce children. In fact the hole wisp is can self replicate. I have been talking about the different parts of the wisp like they were in separate boxes, but in reality everything is distributed throughout the sails base material. The only thing that is centralized is the hormonal gland. When the sail has acquired enough carbon to reproduce it creates another gland. The gland is what limits the size of the wisp. The glands will try to move away from each other. The whole sail will split by mitosis.

OK the 100's of gees I just made up and I have no idea what this thing might be capable of. I don't know what equations to use but I imagine they involve the efficiency of the lasers and the mass of the craft.

The last paragraph is pretty much pure science fiction.

 

[DaveC426913]

Well, let's be real; the whole thing is pretty much science fiction.


What kind of answer are you looking for? Is it plausible in an RPG? That's up to you and the established tech level of the campaign. Do you want science that backs it up? Nope.

Question: you're going to build fleets of these things with all this fabulously advanced technology, and then you're going to sacrifice them on the windshields of your enemies?


Whatever happened to KISS? What about simply showering the enemy fleet with a cloud of pellets moving at relativistic velocities?

 

[{~}]

I am looking for the science to back it up. Weather or not this might be a better option than good old fashoned kinetic kill can be debated till the cows come home.

I did read once that relaivistic projectiles are completely ludicrous in terms of short term technology. This is because massive amounts of energy (in fact all the destructive energy of the weapon) needs to be packed into the projectile at the time of launch, (I mean talk about kickback).

Rather what I have is a super smart relativistic misile. It has no kickback and is much harder to dodge. The economics are overcome with the magic of nanotechnology. Nanotechnology is an assumption we have about our universe. What I am interested in is the physics.

I guess to answer your question well yes that is the general idea, although some times they can serve other purposes as well.

 

[Hurkyl]

Well, here are some of the potential scientific problems that I see.

They are held to the grid by electric cages. The black holes are fed mass and charged particles so they stay at the same charge and mass. Micro black holes evaporate quickly. It is the way the black hole converts its mass, charge and spin into heat that makes them so useful to us.

I'm under the impression that if your black hole is too small, it will radiate high energy photons and miscellaneous subatomic particles. I don't know how big it has to be in order to radiate heat.

The heat given off by the black holes is mostly in the form of incoherent light. This light is sent to the laser array. Light bouncing off the sail is what makes it go. Obviously propulsion is the most power intensive part of a spacecraft , especially one with this kind of acceleration ceiling (in the hundreds of gees).

That wastes energy: the recoil from the laser counteracts the momentum delivered to the sail, generating waste heat. You'd get better performance if you shone the laser away from the sail.

The laser-pushing-sail system is meant for a planetbound laser to push a spacebound sail -- in that situation, the recoil from the laser pushes against the planet, rather than slowing the spaceship.

The laser in and of themselves are only marginally effective as weapons, but they can be used in much more tactical ways.

This is just off the cuff, if your laser carries enough energy to cause your missile to accelerate at 100 g's, I find it very hard to believe it would be an ineffective weapon. It will certainly deliver enough energy to punch a tiny hole through any object it's aimed at. I would expect it to be able to cut through the enemy ship like a knife! (I don't know how quickly you'd be able to cut before it loses its potency, though)

The laser can also be pointed at other sails, to accelerate them as well.

Just remember that the laser gets accelerated in the opposite direction when doing so.