Spaceships and Science fiction

  • #76
Borek
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Even more off topic:

Lastly IIRC from the latest batch of Star Wars films George Lucas made a bizzare government for (I forget the name of the planet where the first one is based) wherein they have an elected Queen who sits out two terms maximum and abides by a constitution...
Electing a King? Not a problem:

http://en.wikipedia.org/wiki/Royal_elections_in_Poland
 
  • #78
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I might check it out :smile: don't get me wrong, sometimes all I want to do is read something so soft you could spread it on your toast in the morning. But generally I'm more of a 4/4.5 on Mohs scale
I don't have a lot of experience with the mohs scale, but after reading through the different levels I'd toss LoGH into like... somewhere around 2 or 3. The sci-fi is pretty darn soft. They don't ever bother explaining how the FTL travel works, it's just "yeah they get around". It's also not... terribly consistent, I suppose.

But that's just the science fiction aspect of it. What makes it a great show is the characters and the plot. Plenty of politics, discussions on stuff like authoritarianism vs. democracy, the role of the military in a democracy, the merits of authoritarianism/democracy. etc. To be quite honest, the science fiction is almost there just to "spice things up" and make it more interesting. It's just a show about two nations going to war, but transplanted into space.

I think my favorite theme of the show is summed up in a quote by one of the characters: "There are few wars between good and evil; most are between one good and another good."

I could probably count the "truly evil" characters on one hand, maybe two. They're all spread throughout the whole setting. In fact, one of the biggest jackasses of the show is one of the most powerful men in the democratic faction.
 
  • #79
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Thank you for your suggestions. :)

Although i have to say i didnt really liked LoGH, but there were good parts I admit. :)
What i despised is Yang Wenlii... the empire attacks a patrol with an another patrol... send there our whole fleet yeah why not... Next time they attack with a BIG fleet, oh it is bound to be a decoy, the real attack, comes from the other direction.
Then the politicians : but Phezzan will not let it... and what did they think, what can a single planet do against a fleet of an empire, if the empire's leader dont respect the status quo?
But again i admit there were good thoughts in it. :)

New BSG i liked it at first :), but at the end of the third season... i hoped the Cylons will win...

On rocketpunk manifesto, we thought about, what can be the closest relative to the pop sci space fighter. (well, maybe its only me, i more like swarms of ships, than big battleships just keep shooting each other)
I think we worked out something : it would be a several hundred tons ship (mostly remote controlled), with nuclear thermo drives, most of its mass is the propellant (monatomic hydrogen). Capable to perform some tenth G acceleration in order to change its orbit, ascend to high orbit from low orbit, then return, or reverse.
Armed with laser jammers, cannons for self defence, (short range) missiles for attack.

It would be the descandent of present day littoral patrol and combat boats, mostly used to maintain peace and order (that is an important task in modern warfare, in Iraq, Afganistan)
In actual combat, unlike a simple missile, it is reusable (yes they will require the support fire of either bigger ships, or planetary defence to keep the mortality rate down) and more adapt in operating in orbital environment, where are cover, background clutter, possibly lots of debris, anti missile mines, satellites, aerial and ground targets.
(In a simple deep space combat, simple missiles are enough, and require less resources. )
The mothership would be the descandant of torpedo boat tenders, it is task is to regroup surface troops and orbital ships between colonies, invade, pacify, secure, aid them.
It can also serve a mobile base for your fleet.

Does that sound a bit plausible?
 
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  • #80
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I think space ships are old school. I don't see how you can take one to Jupiter, much less to another star.

I've got ideas but they are speculative so I ain't saying nuttin.
 
  • #81
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I guess you watched StarGate. :) If you have other ideas, you can share me privately.
 
  • #82
Ryan_m_b
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Does that sound a bit plausible?
Reading through all of that gives me a distinct reminder of reading accounts of how tacticians circa 1900 thought speculative air battles would be. I'm agreeing with ImaLooser on this point:
I think space ships are old school.
The fundamental concept that space craft can be analogised to naval ships automatically handicaps the discussion. The differences between space and the ocean are significant in spite of superficial similarity.
 
  • #83
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"The fundamental concept that space craft can be analogised to naval ships "

I know there are several differences, but i find it hard to ignore certain analogies...
The word battlecruiser sounds better than big size rocket with patrol/attack duties. Frigate sounds better then middle sized patrol spacecraft.
Travel lengths, lots of people sharing the hull of a single vehicle, that travels through a hostile environment, also brings up theese analogies.

Should someone come up with entirely new terms?
 
  • #84
Ryan_m_b
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The problem is the imposition of similarities based on assumptions. For example: the idea that you would have "patrol ships" because patrolling would be a necessary job of military space craft. To have this discussion properly you have to first determine what situations military space craft would be necessary/desirable for as well as determining what technology will be available for them.
 
  • #85
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Ok.

Well it is easier to answer certain questions in an SF operatic setting with the good old magical hyperspace jump drive.

But at first a not so far future scenario i have the following thoughts :

There would be space stations producing stuff requires zero-G, act as luxury hotels for rich people. There would be lunar colonies, mining HE-3 and other things. There would be much cheaper methods to reach orbit than today : induction catapults, laser assisted rockets, skyhooks lifted up by magsailed ships. There can be also orbital habitats for lunar executives who has to be relatively close, but dont want too much exposure to low-G.
There would be near Earth asteroid mines, orbital depots.

Earth still dont has a monolithic government, corporations also have the power of small (or not so small...) nations, there might be corporate warfare, terrorism and organised crime can be also significant.

An orbital fast attack craft (fighter) would have the following jobs : monitor surface, possibly drop kinetic bombs, force suspicious ships (they might smuggle guns or drugs, spies, crime lords, terrorists, or maybe they try to ram you in a 9/11 style) to change their course to your port, abandon resistance. Or maybe destroy them if necessary.
(Well some of theese things supposes that there wont be really strong long range lasers, and kinetics still have an important role.)
A corvette (attack/transport craft) could carry more kinetic bombs, or transport police, military commandos, detainees.

If things get nasty, you might need fast Earth-to-Moon ships, that can reinforce the local ones (frigates, destroyers). (The first two kind of rockets act between LEO and GEO or possibly they land on the surface.)
If things get really bad, you might even need the mothership, that would be a mobile spinning station, that can house lots of fighters, corvettes, marines, supplies.


Later if we could reach even farer, there can be big battleships and destroyers meant to take over particulary valuable asteroid mines, battlecruisers to attack or protect convoys.
 
  • #86
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The bigger they are, the better they are. Assuming for a moment that we are just talking about something like a telescope (that looks for visual and infrared) if the ship has interferometers along it's length then it is in essence a giant telescope (there's an equation for figuring out the resolution of a telescope based on its diameter but I don't remember it). If the ship needs better resolution then what it should do is spread out a bunch of probes in an ever expanding sphere so that they act like one giant telescope rather than loads of tiny ones.

If we're not just talking about telescopes though IIRC a larger ship benefits from being able to house neutrino detectors which would make any ship using a fission or fusion reactor/drive stand out like a flare in a dark field.

Exactly.
Well, i would like to have another question about it.
A Kepler and Hubble can already see many many things, explore the shadows of very distant planets etc. I guess the military could have launched something like that to watch Earth.

Yet as far as i know, that doesnt turned old fashioned recon obsolate...

Why is it? It looked like to me, you could scale up resolution with a huge telescope to see everything you want to see on a certain area of Earth.
 
  • #87
Ryan_m_b
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Hubble can't see anything on Earth's surface, it would be a huge blur. Regardless though...is your question serious? The reason why satellites haven't replaces HUMINT is that they have severe limitations like not being able to see in buildings or overhear/steal/gain through talking intelligence locked in people's heads or other media. As far as I'm aware there's no one not on earth worth getting intelligence out of :rollseyes: Also if we do propose space colonisation that doesn't change much. HUMINT operators will have to use whatever travel is available to get to their destination settlement.

One final but oft repeated point: space is big. There is no analogy for a space patrol.
 
  • #88
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Ok i wasnt punctual enough : when i meant recon, i thought about locating vehicles or machinegun nests, or troops for example, not people inside a buliding, not secret intelligence. And there are still recon vehicles and drones, not just satellites for the former purpose, or am i wrong?

Well unless we introduce certain operatic things, then ok, you dont use a ship just to detect something in space, but if you want to something with a situation, and local forces (if we talk about a situation on the ground) arent enough, then it is good to have a patrol ship IMHO.
(And it only has to patrol between areas of interest and act if necessary, otherwise its simple presence is threatening to bad guys. At first level i think about an operational area of Earth's orbit or Earth to Moon.)
 
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  • #89
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If we're not just talking about telescopes though IIRC a larger ship benefits from being able to house neutrino detectors which would make any ship using a fission or fusion reactor/drive stand out like a flare in a dark field.
Fascinating! I'll have to read up on this. Would you basically need multiple neutrino detectors arranged at distance from each other, in order to pick up relative differences and calculate the position of the source? Or can a single detector obtain the direction of the source?

*goes off to wikipedia...*
 
  • #90
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The thing about space combat is that it is very difficult to hide anything. Even with today's technology tiny things can be tracked.

My guess is that any kind of space combat would be so fast and secretive that it would all be done by computers. There would be no human involvement at all. You would be flying along and either suddenly cease to exist or get a computer message that you just won.

Any ordinary space ship would have a tiny crew that was bored as could be, just waiting for something to repair. Any sort of warship would be completely unmanned.
 
  • #91
Ryan_m_b
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(And it only has to patrol between areas of interest and act if necessary, otherwise its simple presence is threatening to bad guys. At first level i think about an operational area of Earth's orbit or Earth to Moon.)
Space is big. Patrolling between areas of interest is at best going to take days (Earth-Moon system) and at worse years. There is no point sending a craft on a continual loop between interesting locations on the off chance that during its months/year long round trip something might happen at just the right moment for it to be around to help. This is why the idea of patrolling makes no sense.

Similarly if it takes years to get anywhere then by the time you get there the thing to came for is likely to be over. If military presence was deemed to be a necessity then it's likely to be a permanent, on site feature rather than something that is moved around like today.
Fascinating! I'll have to read up on this. Would you basically need multiple neutrino detectors arranged at distance from each other, in order to pick up relative differences and calculate the position of the source? Or can a single detector obtain the direction of the source?

*goes off to wikipedia...*
I'm not sure, I'm guessing several.
The thing about space combat is that it is very difficult to hide anything. Even with today's technology tiny things can be tracked.
Quite, it's even easier when the object in question is several hundred degrees hotter than its surroundings http://www.projectrho.com/public_html/rocket/spacewardetect.php#id--There_Ain't_No_Stealth_In_Space
My guess is that any kind of space combat would be so fast and secretive that it would all be done by computers. There would be no human involvement at all. You would be flying along and either suddenly cease to exist or get a computer message that you just won.

Any ordinary space ship would have a tiny crew that was bored as could be, just waiting for something to repair. Any sort of warship would be completely unmanned.
It really depends on what we mean by space combat. Curiously we don't generalise for anything else, why space?
 
  • #92
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What about orbital patrol? The ranges are smaller.

I think about the descandants of this : http://en.wikipedia.org/wiki/Boeing_X-37

(Ok, than no frigates just destroyers with Earth to Moon range...)

I would be still curious : if we can already see distant planets, why USA sends drones to unfriendly countries, where they are shot down and hacked up? Why cant they solve recon with a big orbital scope? I dont think a RQ-170 Sentinel could enter into buildings, overhear conversations...
Is it because the distortion of the atmosphere, or what?


Otherwise I can agree that short range craft can be remote controlled, but i sure wouldnt trust decision making to compus (at least... ). It would be too much temptation to politicans and military leaders.
A drone operator can still feel remorse, guilt.
 
  • #93
Ryan_m_b
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What about orbital patrol? The ranges are smaller.
You can drop patrol there and just say orbit unless you want a craft tat burns through all its few a short time after deployment. Otherwise sure.
I think about the descandants of this : http://en.wikipedia.org/wiki/Boeing_X-37
I doubt like this. I'm thinking more along the lines of the international space station with more propulsion and weapons. Not a space plane. You can't dog fight in space and there isn't a role that I can see for a fighter type craft between larger craft and smaller missiles.
I would be still curious : if we can already see distant planets, why USA sends drones to unfriendly countries
Firstly our detection of exoplanets is not by seeing them directly, but by observing the effect they have on their sun. Secondly whilst we can see planets in this system there are things that telescopes can't do that we use probes for. Thirdly what we're talking about in this thread is the detection of spacecraft which would not be done by visual means of the craft itself but by thermal means of it and its exhaust. Lastly satellites in Earth orbit have only a tiny amount of the the surface they can see at any one time in their orbit (presuming no cloud cover and its day). No nation has so many satellites that they can see any point on Earth at any time so drones are used (amongst other reasons).
 
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  • #94
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"I doubt like this. I'm thinking more along the lines of the international space station with more propulsion and weapons. Not a space plane. You can't dog fight in space and there isn't a role that I can see for a fighter type craft between larger craft and smaller missiles."

I think that depends on exactly what you want to achieve. (And what kind of engine developments can we achieve.)

Ok if you can barely have enough delta-V to reach a certain target and only want to destroy that, yes you use a missile.

If you want to reach multiple targets, you can provide enough delta-V, and maybe not destroy just capture some of them, i see a role for smaller planes.

For example you might want protect your own satellites meant to watch a country, attack the satellites (and anti satellite missile sites) of that country, that means all of them will fly above that country.
Then you can position a squadron of small ones to a low orbit, where they might protect an own satellite at first, bomb a missile site next, then modify orbit to attack an enemy satellite. (They might use the upper stratosphere to modify their vector?)
During this, you might want to keep your precious station on a high orbit, possibly GEO above your country. (if they have the technology to attack it... yes it can defend itself much better than the small ones, but you can afford to lose some of the small ones, while you dont want to endanger a big station)

Or you want to capture a rocket of a crime lord, before it could reach a safe haven.
A missile cant capture a ship, a plane can fire warning shots to it, and only destroy it if absolutely necessary. Ok you might fire a missile and blow it up, if they modify their course, but you sacrifice the missile.
Assuming that fuel will be cheap enough, and there will be cheap methods to get it to orbit (asteroid mine, induction catapult, space elevator from Moon) it is better to sacrifice fuel then missiles, and care about versatility and reusability.
(Well intercontinental ballistic missiles exists for long, there are also high-precision missiles, but attack vehicles are still needed. )

I have a Mohs scale 5 situation in mind.
 
  • #95
Ryan_m_b
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You're really underestimating how much all that manoeuvring is going to cost in terms of fuel and energy and therefore mass and therefore thrust. Orbital speed it a hell of a lot faster than anything in atmosphere. You can't just shed that and speed off in other directions. On top of that you should brush up on the basics of orbital mechanics, you can't have a squadron of planes hovering under the orbit of a satellite, at least not without constant thrust. On top of that none of the tasks you mention would be best suited to planes over weaponised satellites.

Regarding capturing a craft that's pretty much impossible. It requires you carefully match velocity and gently dock. Not going to be possible if the other craft doesn't want you too, all they have to do is spin their craft along its axis and you're screwed.

I'm sorry but this isn't moh-5, more like 2. I think you're basing too much of this on science fiction and not science.

This thread has gone on long enough with no development. I suggest we take a break until anyone has something definitive to discuss I.e some actual science to speculate on or some fiction to talk about.
 
  • #96
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Ok, weaponised reloadable satellites.
I hope this is a development, if not, than sorry, do what you have to do.


Another things : in space there are pretty much radiation. Earth is protected by its magnetic field from the worst things. Could this be a viable method to protect spaceships (colonies) instead of thicker hulls?
 
  • #98
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Thank you.


A bit more about protection and sci-fi : i found a link in this forum, in an experiment they used magnetic fields and lasers to keep particles at one place. When they released them, they drew away that much energy, that they called their state beyond absolute zero...
Is there any chance that this super entropy-less state could be used to create some supersolid armor? (well a bit like to the concept of energy shield)

Second, about induction catapults, mass drivers, coilguns.
What could be the theoretical limit of acceleration, that a simple solid object could withstand without ripped to plasma dust?

So for example, if one would like to take out a meteor, and boost a projectile to 10km/s in order to do it, what could be the minimum length of the coilgun?
(Assuming, with some next generation technology, they can solve power supply, engineering, recoil etc)
 
  • #99
Ryan_m_b
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Here is the PF discussion on the topic https://www.physicsforums.com/showthread.php?t=662268.

Re acceleration if it is uniform across the object then the answer is infinite. If not it's down to the material properties of whatever it is made out of. Re length it depends on how fast you're accelerating. Ask in one of the physics forums if you want to learn how to work it out.
 
  • #100
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Ok, thank you.

(And again, sorry for our previous misunderstainding. :( I should have made it clear that I imagined the orbital craft to operate in a wider orbital belt, so it could observe and attack more, gradually modificating course during turn around the planet, and by capture, i meant, force to surrender by lethal threat. )
 

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