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Post by newageofpower on Dec 9, 2016 8:36:12 GMT
Hmm I think we are discussing different definitions of stealth ship. So let's clarify! My stealth ship has a nano material anti-reflective coated hull My stealth ship cold runs, only doing burns deep in space My stealth ship has a massive radiator flush with its hull to minimise emissions visibility and ensure it can only be seen from one side(that faces away from your sensors) My stealth ship never enters closer the 40Gm of your ships My stealth ship launches missiles from high up in the gravity well with magnetic acceleration so they drop down like rain My missiles cold run only using compressed gas and initial magnetic acceleration to set approximate trajectories. My missiles get most of their velocity from falling into the gravity well My missiles go at roughly 10-50km/s just from riding down the gravity well My missiles are 100kg payloads with 100kg of rocket fuel and 5s burn time for last second trajectory adjustments My missile hits with between 5GJ and 100GJ of energy due to terminal velocity That's my stealth ship First of all, nanocoating obeys Thermodynamics; it emits blackbody radiation. If your ship's exterior is higher than 3-22 Kelvin (depending on sensor refinement) it will emit IR above 3-22k... and that can be spotted with IR. My cheap sensors are everywhere. My cheap IR sensors can detect normal radiator temp (say, 371k for crew cooling) at orbital distances, especially against a cold background. Anything above 3K is detectable, in theory. With enough wide-angle IR sensors, deployed around every large body of interest, even deep space burns will be noted. Since your missiles are "dropping" with gravity, and you are dropping from extreme range, they will take a significant timeframe to accelerate. During this time, they will be warmed by the Sun. I can spot them with IR, again. If you somehow bypass the IR, you enter the Garrisoned Zone. Once you are near my Hill Sphere, FELs (which already exist) will pump Xrays towards any 'holes in space', or just sweep randomly. If you trip an IR sensor's flag, an nuke without filler (to convert hard radiation to heat) will be detonated in the vicinity to shower you in xrays. Multi-gigawatt active scans are basically guaranteed to light you up. My MegaHubble sensor arrays will see your ship/missiles incoming from traces of UV (almost impossible to stop with nanocoatings/etc) and Xray (basically impossible to stop) emissions from active scan sweeps. Although your missiles are smaller than your ship, scanners obey the inverse square law and recieve exponentially more resolution the closer you get. Also, if the exterior of your ship isn't below say 3-22 kelvins (depending on sensitivity of sensor and amplitude of sweep), even an IR sweep will generate a signal louder than background! By emplacing sensor stations at multiple sites, there becomes basically no way to "sneak" ships or missiles through. Multigigawatt+ death stars will eat the missiles, or damage them enough they vaporize during re-entry. Interceptor nuclear missiles (with multiple Teller-Ulam stages measuring in the dozens of megatons, at least) will do the same. If you try to move a large object I cannot redirect easily with multimegaton devices, I can see it from much further out and send a fleet (with combat engineers and propulsion systems) to stop you. Your stealthship doesn't even beat cheap spammed IR sensors. How do you get through a properly set up active sensor and defense grid?The proposed ship of yours fails at every stage of your plan. Sorry.
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Post by amimai on Dec 9, 2016 8:39:43 GMT
Your missing one important thing in all your wonderful calculations... distances.
Read up on the inverse square law, k thnx bai!
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Post by newageofpower on Dec 9, 2016 8:49:28 GMT
Your missing one important thing in all your wonderful calculations... distances. Read up on the inverse square law, k thnx bai! ... I specifically mentioned the inverse square law... ... Space is insanely cold. Your non-cryogenic ship (at 300+K) stands out like a glowing lamp. Sure, resolution on cheap shitty drones at gigameter range is perhaps 1 pixel if I'm lucky. But that pixel stands out. It's relayed to other, bigger, more powerful passive sensors. Once you get closer, multiple gigawatts of energy sweep for intruders. Multi-meter sensors - arrayed with dozens of other sensors of equal fidelity seek any hint of a return. Even a cryogenic ship probably could not penetrate this. Your ship that's glowing over 300k above background is easy prey. Acceleration by gravity is, of course, slower than boosted acceleration. If I pick them up early; they're dead. Even if I pick them up late, my defense grid can prevent them from connecting with my population center.
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Post by amimai on Dec 9, 2016 8:54:05 GMT
But that's the thing, it doesn't... my ship is at worst a GW heat source radiating from several Gm range, stars are YW sources radiating from light years away.
Simply put at 40Gm my ship will look colder to your sensors then any star in the sky because W/m2 would be spread out across the entire area of that sphere
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Post by shiolle on Dec 9, 2016 10:20:20 GMT
Your ships move relative to the stars. Your directional radiation doesn't work because, as lore states, there are swarms of tiny sats in various orbits so you can't hide your emissions. Once you turn on your engines "in deep space" there are hundreds of small silicon chips exclaiming "look, a new star!" and then they know your mass, your acceleration, your trajectory and probably the type of your ship.
I mean, this topic has been done to death and you are not presenting any new arguments. Perhaps you will be better off disguising your fleet as freighters instead. Scratch that, just use actual freighters if you are not going to armor them anyway. It will put all civilian traffic at risk, sure, but it looks like a lot cheaper and surer way to disguise your intentions than specially built ships with tiny payloads and limited capabilities that bet everything on a strategy that will likely fail.
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Post by thorneel on Dec 9, 2016 10:36:36 GMT
My stealth ship is a Hydrogen Steamer My stealth ship is a drone My stealth ship is an interplanetary ballistic missile launched by a camouflaged mass driver (camouflage is there so you cannot tell where it is pointing at or when it fires) My stealth ship is a weapon of mass destruction My stealth ship either rely on kinetic energy, a nuclear payload, a nuclear-propelled payload (NEFP) or a nuclear-pumped X-ray laser My stealth ship is used en masse, on as divergent trajectory as possible My stealth ship may carry smaller stealth ships for swarm attacks, if swarm attacks happens to be more practical that way My stealth ship arrives so far that once close-range detection (UV or X-ray lidar, star occultation) are useful, there is almost no time to intercept it - numbers and surprise are used to overwhelm defences My stealth ship is meant to entirely destroy surface/asteroid and orbital installations, and Kessler-spike orbits for larger bodies My stealth ship is meant to wipe out unprepared warships and military installations as well, with clouds of cold pebbles (nano-steamers) or the aforementioned NEFP or nuclear-pumped lasers for standoff attack to minimise time in interception range My stealth ship may eject its laser-armoured payload to better survive laser defences My stealth ship will hopefully never be built, because doing so would be enough to spark a war to stop its construction - you don't build it if you don't intend to Dr Strangelove someone. My stealth ship would be a poor MAD-enabler: with more than two sides, you won't know who attacked you - and against who to retaliate. In addition, someone may decide they managed to neutralise the hidden launchers or missiles waiting in standby orbits of the other side and launch their own attack, only to be direly mistaken. My stealth ship may work even better as an interstellar ballistic missile, at the near-relativistic (or even relativistic) speeds required by such distance, there will neither be time to intercept it nor anything to survive impact
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Post by shiolle on Dec 9, 2016 12:00:00 GMT
A good idea, thorneel although some of the points I find unlikely. We are now moving more and more away from actual ships into the realm of first-strike automated weapons, but that's fine too. First, your stealth ship looks either insanely huge or a part of a large swarm, which for our purposes has similar drawbacks. CoaDE might suggest you can use technology from the sixties to build nuclear hand grenades, but I don't think it actually reflects reality. In either case your huge camouflaged mass driver either doesn't deliver much energy to the ship (and thus you have to rely on rockets for launch) or it will glow brightly as it exits the barrel. I think a series of stars rapidly raising from the surface of a moon and fading as they pass busy commercial orbits will send waves of panic across the civilian population just like seeing ICBMs launch will cause panic today. People will know what what signs to look for. If it's situated on some asteroid no one is likely to visit, you won't be able to construct it in secrecy anyway and the launch can still be seen. Since your stealth IPBM doesn't seem to be able to have much delta-v there will be months before they arrive at their targets. If any (even one) such launch has been observed or if they are spotted in flight, your enemy will have plenty of time to retaliate, and they won't bother deciding who did this before launching their own IPBMs. And thus your argument that it will be a poor MAD enabler doesn't hold. How do you imagine that? "Ok, we don't know who launched it. I guess we die now?" ICBM launch was almost triggered by a meteor once, and anyone launching these things will know that if anyone spotted anything (and they likely will) he is screwed. If these things are built, they will be built in enough quantity to cover all likely targets. Near-relativistic and relativistic weapons can't be made stealthy anyway, at least while we are confined to one solar system, and thus everyone will see it long before it is accelerated to its terminal velocity and either intercepts it or launches their own retaliatory strike.
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Post by shurugal on Dec 9, 2016 13:41:28 GMT
My point is, three, five, or even ten arrays of ten CoADE Hubbles will be cheaper than, say, ten Gunships or ten LaserStars. If I can only afford 2 gunships or 2 hubbles, obviously buying the warships is better, but when I can afford a dozen warships the sensors become a steal in comparison. If you divide up your fleets to fly through different corridors I probably have enough local margin of superiority that I can probably defeat each in detail with relatively low casualties; otherwise I would be signing concessions instead of fighting a war. If you want to launch them so that they all arrive around the same time; that's multiple launches over a significant window where your fleets are *le gasp* not garrisoning your Hill Sphere. Either you are winning the war, fairly confident I am not about to gank you, or insane. I'm going to re-address a few points i may have skimmed over or skipped entirely last night, because I needed to go to sleep. To start with, using the Hubble to scan for threats is gonna be pretty damned ineffective. As I mentioned earlier in this thread, a full-sky scan with the Hubble would require ~1 million years to complete. Now, you pointed out that we can give the Hubble a larger aperture to reduce exposure time. So, let's assume we can cut exposure time from 10 minutes to 1 second (600 times shorter), it would still take 1,666.66 years to conduct the scan. Your 10 arrays of 10 will cut that down to 16.66 years. If you want to cut that down to 1 year, you need to up your Hubble Fleet to ~1,600 telescopes. Considering that an Earth/Mars Hoeman Transfer can be managed in under a year, you need to double that to ~3,200 so your first scan of an approaching threat is not a week before they arrive. Now, let's talk about the infrastructure you are going to need to support these telescopes. Manufacturing them all and placing them in orbit is going to beggar you, by itself. But let's assume you somehow get them there and still have enough money to buy lunch when you're done (space elevators, that'll at least let you put them in GEO orbit for 'free'). You're going to need several literal fleets of engineers to maintain them all, but that's still not going to be your biggest cost of operating them. Image processing is. The current Hubble telescope Wide Field Channel produces a 16-megapixel image over a 0.003 Deg 2 FoV (202x202 arcseconds) A full sky scan with 5% overlap is ~14.5 million scans. You will be generating ~230 trillion pixels per sky scan. If we were to print this scan at 300 DPI, it would cover ~500 square kilometers. If we printed it on 8.5"x11" paper, and glued them end-to-end, it would reach from the earth to the moon, 10 sheets thick. If you displayed these images on a 60" TV (1 Sq m) at 2 images per second, it would take 15 years, 24 hours a day, to show them all. And you want to make one of these pictures every 6 months or less. I don't even know how to convey an estimate of how long it would take to process all that imagery, or how much computing power you would need to do it fast enough to be useful. Actually, that was just one point, and if that doesn't convey a sense of the scale of task you are talking about accomplishing by surveying the entire solar system at a scale to detect starships, I won't even know how to proceed with the conversation.
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Post by concretedonkey on Dec 9, 2016 15:25:35 GMT
Your ships move relative to the stars. Your directional radiation doesn't work because, as lore states, there are swarms of tiny sats in various orbits so you can't hide your emissions. Once you turn on your engines "in deep space" there are hundreds of small silicon chips exclaiming "look, a new star!" and then they know your mass, your acceleration, your trajectory and probably the type of your ship. I mean, this topic has been done to death and you are not presenting any new arguments. Perhaps you will be better off disguising your fleet as freighters instead. Scratch that, just use actual freighters if you are not going to armor them anyway. It will put all civilian traffic at risk, sure, but it looks like a lot cheaper and surer way to disguise your intentions than specially built ships with tiny payloads and limited capabilities that bet everything on a strategy that will likely fail. 100 times this. Reminds me of Club K
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Post by Crazy Tom on Dec 9, 2016 16:41:33 GMT
Reasoned debate is all well and good, but this discussion is straying into personal attacks. Let's keep it clean, shall we?
And remember, you're talking about a theoretical situation inside a video game, so hook up to a heat sink and chill.
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Post by amimai on Dec 9, 2016 16:47:17 GMT
Reasoned debate is all well and good, but this discussion is straying into personal attacks. Let's keep it clean, shall we? And remember, you're talking about a theoretical situation inside a video game, so hook up to a heat sink and chill.
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Post by newageofpower on Dec 9, 2016 22:00:23 GMT
But that's the thing, it doesn't... my ship is at worst a GW heat source radiating from several Gm range, stars are YW sources radiating from light years away. Simply put at 40Gm my ship will look colder to your sensors then any star in the sky because W/m2 would be spread out across the entire area of that sphere That doesn't work because star charts exist... plus, I'm never scanning you from only one direction. Anyways, other people have responded to you quite adequately, and you haven't presented a (any, to be honest) good counterargument. I'm going to re-address a few points i may have skimmed over or skipped entirely last night, because I needed to go to sleep. To start with, using the Hubble to scan for threats is gonna be pretty damned ineffective. As I mentioned earlier in this thread, a full-sky scan with the Hubble would require ~1 million years to complete. Now, you pointed out that we can give the Hubble a larger aperture to reduce exposure time. So, let's assume we can cut exposure time from 10 minutes to 1 second (600 times shorter), it would still take 1,666.66 years to conduct the scan. Your 10 arrays of 10 will cut that down to 16.66 years. If you want to cut that down to 1 year, you need to up your Hubble Fleet to ~1,600 telescopes. Considering that an Earth/Mars Hoeman Transfer can be managed in under a year, you need to double that to ~3,200 so your first scan of an approaching threat is not a week before they arrive. Now, let's talk about the infrastructure you are going to need to support these telescopes. Manufacturing them all and placing them in orbit is going to beggar you, by itself. But let's assume you somehow get them there and still have enough money to buy lunch when you're done (space elevators, that'll at least let you put them in GEO orbit for 'free'). You're going to need several literal fleets of engineers to maintain them all, but that's still not going to be your biggest cost of operating them. Image processing is. The current Hubble telescope Wide Field Channel produces a 16-megapixel image over a 0.003 Deg 2 FoV (202x202 arcseconds) A full sky scan with 5% overlap is ~14.5 million scans. You will be generating ~230 trillion pixels per sky scan. If we were to print this scan at 300 DPI, it would cover ~500 square kilometers. If we printed it on 8.5"x11" paper, and glued them end-to-end, it would reach from the earth to the moon, 10 sheets thick. If you displayed these images on a 60" TV (1 Sq m) at 2 images per second, it would take 15 years, 24 hours a day, to show them all. And you want to make one of these pictures every 6 months or less. I don't even know how to convey an estimate of how long it would take to process all that imagery, or how much computing power you would need to do it fast enough to be useful. Actually, that was just one point, and if that doesn't convey a sense of the scale of task you are talking about accomplishing by surveying the entire solar system at a scale to detect starships, I won't even know how to proceed with the conversation. I had to go to sleep too, so I feel your pain. To start with my response; no, we're not actually using Hubble copies. The Hubble is an instrument tuned for interstellar-intergalactic range survey; we're just using systems of equal or greater sophistication for active scanning modules. More importantly, I think we have fundamental misunderstanding of each other's position on manufacturing. It sounds like you believe heavy industry will still be done mostly deep in a gravity well, whilst I believe that CoADE is done mostly with Zero-G manufacture. I mean, creating surfaces that are perfectly smooth down to the micron level is expensive on Earth, but likely to be much easier with orbital factories; there's no way my minimissile drives could be so dirty cheap otherwise. Building a multikiloton vessel (ala CoADE) on Earth and boosting it into space would be cost prohibitive today; but mining resources from low G bodies (asteroids?) and constructing what you need in low gravity... Much more plausible. Similarly, much of the cost of an precise sensor array can be greatly reduced with orbital industries. Processing sensor data is not the challenge you think it is; processing power is not only growing every generation but simultaneously getting cheaper as well. Even more importantly, expert systems that automate data sieving and analysis are growing exponentially more capable. You haven't even responded to the spysats near Mars noticing the conspicuous absence of your Navy, so I don't know where to proceed either. It seems as if we are working off fundamentally different understandings of the setting.
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Post by shurugal on Dec 9, 2016 23:17:34 GMT
You haven't even responded to the spysats near Mars noticing the conspicuous absence of your Navy, so I don't know where to proceed either. It seems as if we are working off fundamentally different understandings of the setting. Rest assured that I shall, but doing the math on Operation Hubble Flood took all the time I had before I had to report for duty this morning. When I have some free time, I will address it in detail, but the gist is that my fleet is not going anywhere.
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Post by ross128 on Dec 9, 2016 23:47:59 GMT
The cost of a massive orbital sensor array is actually quite easy for a multi-planetary society to justify even in peacetime, because incoming ships/missiles aren't the only thing they have to worry about: the array's primary purpose would likely be to identify and track asteroids in order to prevent collisions.
Colonies that lack a breathable atmosphere will be particularly interested in any asteroid large enough to pop a dome. Clusters of small asteroids will also throw up a red flag, because a bunch of small holes in a dome can be just as much of a problem as one large hole.
So most colonies are likely to have a strong vested interest in having plenty of warning about any object larger than a tennis ball that happens to be on a collision course, whether it was launched by a hostile entity or merely some unfortunate physics. Even Earth will start to worry about smaller and smaller objects as satellites and space stations proliferate, because they will increasingly have a large amount of property and personnel that isn't shielded by the atmosphere.
This mindset also means disguising your attack as a group of asteroids isn't a viable tactic, because anybody in their right mind would shoot down actual incoming asteroids anyway.
Naturally, this also means anything more energetic than said asteroids will be seen as even more of a threat.
There is technically one type of "space stealth" that is practical if you have a nearly infinite supply of energy though: Relativistic Kill Vehicles. If you accelerate something up to 99%+ of c, it'll arrive hot on the heels of its own light cone. It's not what people typically think of as "stealth" to be sure, it'll be heavily blue-shifted and you'd be able to see the launch event from the next galaxy, but it's technically invisible the same way a supersonic bullet is "silent". It gives off plenty of light, but by the time you see it you're already dead.
Though, everybody in the galaxy (and eventually most of your local cluster, probably) who is advanced enough to know what an RKV is would know that somebody just got pasted by one, and that it was launched in your neighborhood. They might decide you're not a very good neighbor.
Of course, it also depends heavily on how quickly you can accelerate it. If you need a few hundred years to hit 99%c, then your target will be able to see the beginning of the launch event a hundred years before the shot hits. They might have time to move out of the way (which is the only defense against an RKV).
An interplanetary super-laser might be able to achieve a similar style of surprise attack, where they can see the attack just fine but because it travels at the speed of light, seeing it and being hit by it are the same thing.
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Post by jasonvance on Dec 10, 2016 0:00:23 GMT
The cost of a massive orbital sensor array is actually quite easy for a multi-planetary society to justify even in peacetime, because incoming ships/missiles aren't the only thing they have to worry about: the array's primary purpose would likely be to identify and track asteroids in order to prevent collisions. Colonies that lack a breathable atmosphere will be particularly interested in any asteroid large enough to pop a dome. Clusters of small asteroids will also throw up a red flag, because a bunch of small holes in a dome can be just as much of a problem as one large hole. So most colonies are likely to have a strong vested interest in having plenty of warning about any object larger than a tennis ball that happens to be on a collision course, whether it was launched by a hostile entity or merely some unfortunate physics. Even Earth will start to worry about smaller and smaller objects as satellites and space stations proliferate, because they will increasingly have a large amount of property and personnel that isn't shielded by the atmosphere. This mindset also means disguising your attack as a group of asteroids isn't a viable tactic, because anybody in their right mind would shoot down actual incoming asteroids anyway. Naturally, this also means anything more energetic than said asteroids will be seen as even more of a threat. There is technically one type of "space stealth" that is practical if you have a nearly infinite supply of energy though: Relativistic Kill Vehicles. If you accelerate something up to 99%+ of c, it'll arrive hot on the heels of its own light cone. It's not what people typically think of as "stealth" to be sure, it'll be heavily blue-shifted and you'd be able to see the launch event from the next galaxy, but it's technically invisible the same way a supersonic bullet is "silent". It gives off plenty of light, but by the time you see it you're already dead. Though, everybody in the galaxy (and eventually most of your local cluster, probably) who is advanced enough to know what an RKV is would know that somebody just got pasted by one, and that it was launched in your neighborhood. They might decide you're not a very good neighbor. Of course, it also depends heavily on how quickly you can accelerate it. If you need a few hundred years to hit 99%c, then your target will be able to see the beginning of the launch event a hundred years before the shot hits. They might have time to move out of the way (which is the only defense against an RKV). An interplanetary super-laser might be able to achieve a similar style of surprise attack, where they can see the attack just fine but because it travels at the speed of light, seeing it and being hit by it are the same thing. hitting 99% c with conventional tech is quite the undertaking in both power and mass. For example my ~2% c space ship has a mass of 3,290,000,000kg and cost of 31.6Gc and requires 4TW. To get to ~90%c about 300PW would be needed (just scaling up with more reactors / radiators and proportional amounts of extra fuel).
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