tag:blogger.com,1999:blog-7494544263897150929.post7150876182699430512..comments2024-03-18T13:11:39.192-07:00Comments on Rocketpunk Manifesto: Space Warfare II - Stealth ReconsideredRickhttp://www.blogger.com/profile/16932015378213238346noreply@blogger.comBlogger100125tag:blogger.com,1999:blog-7494544263897150929.post-15336249916567434012021-06-26T10:24:06.543-07:002021-06-26T10:24:06.543-07:00Necromancy rules!
Leaving aside various means of ...Necromancy rules!<br /><br />Leaving aside various means of camouflage, any vessel capable of significant delta-V will be easily thermally visible *at distances close enough to do damage*, unless you posit an interplanetary superlaser, which would suffer lightspeed lag anyway. A one-pixel target spotted across the Solar System is not a target, it's a background detail.<br /><br />One factor about thermal sensors is, they need to be cold to operate. Present day tech needs cooling often down to cryo temperatures, so anything that heats the ship or stops it from radiating heat, could lead to possible sensor degradation. Heat pumps will help (and hinder, of course).Saint Michaelnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-79904183774787287712019-09-16T06:57:34.786-07:002019-09-16T06:57:34.786-07:00I don't think that's necessarily impossibl...I don't think that's necessarily impossible, it just seems like it has practical issues. It would be awfully heavy. Your mirrors and fiber optics better not absorb too much of that infrared either. And I take issue with the idea of a nice neat point source radiator in a parabolic mirror. Everything on your ship radiates, including the pipes that get the fluid to your spherical radiators.Martin Mnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-58816593381790871552014-11-20T07:58:58.704-08:002014-11-20T07:58:58.704-08:00Im sure I am missing something but I don't get...Im sure I am missing something but I don't get the obsession with the need for massive radiators that stick out the side of the space ship. Why cant we have millions of very small spherical radiators that radiate infrared inside parabolic reflectors aimed at infrared versions of optical fibers. The optical fibers coalesces into to a single optical fiber that itself emits into a parabolic reflector that focus Infrared radiation away from the spaceship. it wont be lazer like cone but it will likely be better than 60 degrees mentioned in the article. Infrared reflective materials are very effiant but obviously this system will absorb some of the IR released from the small spherical radiators. However due to the fact that you can use layers of these inside the volume of the spaceship you can have many times the surface area of a simple external radiator. No doubt I am missing an obvious reason this would not work, or have misunderstood a basic scientific principle.Anonymoushttps://www.blogger.com/profile/14213271351868872387noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-33609572188187321372013-04-29T18:03:18.817-07:002013-04-29T18:03:18.817-07:00The arguments stating "there is no stealth&qu...The arguments stating "there is no stealth" run along the lines of the total power emitted from a 100 yard long ship even at room temperate is enough to be viewable from the HST for 500,000,000 miles or so.<br /><br />The counter argument to that is that the HST must *know* where to look to spot something that dim. As Space Watch keeps demonstrating (when it finds hunks of rock much larger only after they fly by the Earth.<br /><br />Obviously you won't be able to "Stealth" any sort of "torch" ship. However, something with ion thrusters or other much lower power engine won't be terribly obvious. You will likely not see it coming unless you are looking for it.<br /><br />Once someone does spot you though, there will be no place you can hide as long as you are not near a major body.Jim2Bhttps://www.blogger.com/profile/13926368791623148384noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-78838743107363093152013-02-10T22:27:27.482-08:002013-02-10T22:27:27.482-08:00I wont start a flame war by making a blanket state...I wont start a flame war by making a blanket statement as those are often wrong anyway. that having been said, this artical and the subsiquent posts don't take into acount every possible senario so making a blanket statement such as stealth is imposible in space is also wrong. while perfect stealth (if achived) would render the stealth craft undetectable it would also render every thing else undetectable to the stealth craft as every form of EM radiation and matter emition would be blocked from entering or exiting an area around said craft. Therefor if one could bend the EM state around the craft and prevent any EM state from leaking out save for a selected band used (presumably) by the craft in question it would be as stealthy as any stealth aircraft (Since they are not actually completely undetectable in themselves). Thus you would reduce the posibility of detection to a minimum, while not eliminating it completely. Also as long as the thermal storage method and the power used to bend the EM state around the craft held up it could maintain said stealth. that being the case, nothing could maintain stealth indefinatly, but thats not really the question here.<br />Ok so, for example say you have two waring ships and one is equiped with a cloak that bent EM states around it. If the enemy ship (the one with no cloak) sent sensor beam A at the cloaked ship it would presumably bend around the ship and continue on its marry way out into space making the enemy vessle belive nothing was there since it recieved no report from beam A. Now if the field bent only say 95% of beam A around the cloaked ship and the other 5% was small enough amount for the ship to absorb it could presumably still go undetected but have a passive sensor system of sorts. this however would fail if beam A was being intersepted by a reciever as it would register said 5% drop in beam A (presumably it could compensate for the divergance of beam A in its calculation of how much of beam A arrived at the reciever).<br /><br />In summory while being completely undetectable might be possible it would be utterly useless as the undetectable ship would not in itself be able to detect anything else. however stealth and undetectable are not of neccesity the same thing. Thus stealth may be possible but making it absolute would be useless.<br /><br />BTW if one were able to bend the EM states around a ship you would not nessisarily violate physics, such as thermodynamics and relitivity (which is looking more and more like its inacurate anyway), as we do not know enough about the EM states to claim that we know every thing.<br /><br />also i know i cant spell, but one need not be good at spelling to be a scientist. lol. MS word spell check is a lifesaver.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-89672772790478616512012-11-26T09:49:50.044-08:002012-11-26T09:49:50.044-08:00Sorry to dredge up an old post, but I often see pe...Sorry to dredge up an old post, but I often see people stating "you can't hide in space" as a fact, but I haven't been able to piece together the evidence to reach that conclusion on my own.<br /><br />If someone could point me to some resources where I could do the math on IR output, sensor sensitivity, etc. so I could see the numbers for myself, I would really appreciate it!<br /><br />Like I said, I've had a hard time finding this data, and the fact that it's so hard to find 1km wide asteroids (which are around room temperature, I believe) makes me think that it would be essentially impossible to find a 30m long spaceship specifically designed to be hard to detect. But everyone seems so adamant about it, there must be some evidence somewhere!<br /><br />I just can't find it for the life of me.Charles Ahttps://www.blogger.com/profile/00941603544547428940noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-5202008481348193352012-08-28T14:11:52.879-07:002012-08-28T14:11:52.879-07:00Hey, sorry for possible noob question (Also this t...Hey, sorry for possible noob question (Also this thread is rather old now so please feel free to ignore). What about autonomous drones? They wouldn't need life support, obviously, so they could run VERY cold when not burning their engines, and furthermore, they could be very light, so their burns would be a lot smaller. Wouldn't that reduce effective detection distance by a lot?Anonymoushttps://www.blogger.com/profile/12957906553433189738noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-77438958791519816082012-06-13T10:38:58.888-07:002012-06-13T10:38:58.888-07:00Sorry, this is a bit outside of my area of experti...Sorry, this is a bit outside of my area of expertise. However if the basis of detection and classification is predicated on the detection of radiation emissions why not simply crank out extra radiation. If the whole point of this is that they'll know you're there, why give them a freebie of WHAT you are. A given IR/radiation output might match up to a 100 ton object accelerating at 10 m/s using a particular type of drive. Throw on some over grown heat lamps (for IR), radiation emitters, etc. that are spectrum matched to your drive output and blaze away. Now you appear as a larger object accelerating at the same rate. <br /><br />If all your contacts appear as say a "battleship" (for lack of a better term) accelerating at full thrust, vs a bunch of "scout ships" accelerating at the same rate your tactical response will be much different. Getting into visual range to tell the difference between different types of vessel is required. <br /><br />As many of the posters have mentioned, tactical and even strategic surprise don't require "stealth" just misdirection. As I prefaced this, this is not my area of expertise so if I'm off base please let me know.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-84056489535906937202012-06-05T23:01:16.647-07:002012-06-05T23:01:16.647-07:00Found it! Helps if I search for thermal vs infra...Found it! Helps if I search for thermal vs infrared: http://www.bbc.co.uk/news/science-environment-17518210Anonymoushttps://www.blogger.com/profile/16738064736682131691noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-41172672613273912442012-06-04T07:19:50.021-07:002012-06-04T07:19:50.021-07:00Rick,
Having trouble tracking down the original a...Rick,<br /><br />Having trouble tracking down the original article (it was in a BBC article but I'm only finding an older, related article regarding a Tank looking like an SUV in IR; this was NOT the article I recently read).<br /><br />This is the same paper I believe, albeit from a different source:<br /><br />http://www.opticsinfobase.org/oe/fulltext.cfm?uri=oe-20-7-8207&id=231514<br /><br />Some similar reading on meta material cloaking:<br /><br />http://arxiv.org/ftp/arxiv/papers/0709/0709.0363.pdf<br />http://etd.fcla.edu/CF/CFE0003201/Shelton_David_J_201008_PhD.pdfAnonymoushttps://www.blogger.com/profile/16738064736682131691noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-78171797729210790482012-06-02T07:19:23.279-07:002012-06-02T07:19:23.279-07:00Welcome (slightly belated) to new commenters!
Nuc...Welcome (slightly belated) to new commenters!<br /><br />Nuclear explosions are about as un-stealthy as you can get! :-) Also, in space the debris cloud expands and dissipates very quickly. But the initial flash might blind sensors.<br /><br />I used to be a big fan of fragmentation clutter (on a smaller scale), but I've come to think that numerous small target seekers are likely to be cheaper and more effective.<br /><br /><br />The article sounds interesting - is there a link? My instinct is that metamaterials like this would be more useful in a ground clutter environment than in space. But that is without reading the paper.Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-86125553959395365022012-05-31T20:25:37.739-07:002012-05-31T20:25:37.739-07:00I realize this is a week or two old but for a pers...I realize this is a week or two old but for a personal writing project I've been doing some research into this. A new development in the field of metamaterial cloaking opens up a possibility. For most frequencies of light (visual, IR ultraviolet, Gama rays, xrays, terrahertz) and even sonic ranges scientists have figured out how to use metamaterials to construct a cloak. <br /><br />Honestly the description of the paper for IR cloaking reads like classic technobabble but these are real scientists and their work is posted on arvix. But basically the metamaterial allows light/sound of specific frequency to flow through the material, allowing you to build a shell that acts as a cloak for whatever is inside. You even get a heat concentrator that allows you to control the temperature the material gives off, so if the background temp changes you remain invisible. <br /><br />Now having this cloak survive space travel intact is another story, but if your ship has a low refractive index (also possible with metamaterials) and is effectively invisible on IR if you aren't burning/adjusting course, I'd say the detection chances have just dropped dramatically. <br /><br />Thoughts?Anonymoushttps://www.blogger.com/profile/16738064736682131691noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-70278430935799470922012-05-13T19:26:35.002-07:002012-05-13T19:26:35.002-07:00I have a couple of suggestions for stealth scenari...I have a couple of suggestions for stealth scenarios.<br /><br />The first one isn't really stealth, more of a "exploitation of uncertainty". Basically during battle you'd set off a nuke between you and the enemy. This would up the background radiation so as to camouflage your ship. Might be useful if you wanted to pull an unexpected maneuver, and appear suddenly out of the radiation cloud. This form of blinding may in some situations be superior to the more efficient and accurate 'laser their sensors' method, as you could never be sure you had got them all, while a massive nuclear blast is almost guaranteed to give you cover. Unless of course they manage to get sensors behind you.<br /><br />My other suggestion is to redirect an asteroid. You would have to do all of your thrust and correction outside their sensor range, which would require a lot of accuracy. Also you'd have to come in on a believable trajectory, ideally from the opposite direction to what they expect. A sufficiently large asteroid could easily hide the heat signature of an AI or skeleton crew ship. At the closest point you'd suddenly pivot and hit them where it hurts with a laser. Maybe one of those x-ray single shot ones? Ouch. This trick would only work once though, they'd learn to blow up all near flying asteroids just in case.<br /><br />A different asteroid scenario is one where you catapault a whole bunch of rocks at the enemy, and hide ships in only a few of them. They'd know they were being attacked, but wouldn't know which rocks to destroy. If they targeted an asteroid with a ship inside it, it would return fire and evade, turning into a normal attack. They wouldn't know how many ships were attacking however until they'd destroyed every rock. Their tactic may then be to give each only a little fire to see if it responds; I can imagine a tense scene with a commander accepting enemy fire in an attempt to fool them into believing his ship is only an asteroid. Then of course you'd turn and hit them with everything. More boringly, but with less casualties, this kind of attack could be done with droids.<br /><br />That kind of attack perhaps isn't really stealth however.TokyoTrainStylehttps://www.blogger.com/profile/07022932548648681244noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-14572338258016577422012-04-26T13:12:08.724-07:002012-04-26T13:12:08.724-07:00Also, big problem with "big damn scope",...Also, big problem with "big damn scope", interplanetary-range detection is that for a given resolution, the farther out you try to look, the smaller the field of view gets, and (because the scope is getting physiaclly bigger and bigger) the harder the intrument is to accurately steer.Tonynoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-10362054111688401402012-03-21T09:22:30.741-07:002012-03-21T09:22:30.741-07:00I wonder how easy it would actually separate an IR...<i>I wonder how easy it would actually separate an IR decoy "lamp" drone from an actual warship. I've heard the usual argument about emission lines, but that usually involves doing spectrography on it, something that takes hours in real life to get the proper exposure. </i><br />That would depend on what you're doing. We're not trying to do highly precise science experiments here. If we have an unknown ship, we know its mass and the drive power, and we have a database of engines, then all we have to do is match the drive signature to one of those engines. I'd be surprised if there were more then a couple dozen candidates, and who cares if it's power X Type 3 Mark 4 or Type 3 Mark 5? We know it's power X.<br /><br />Any stealth engine is by definition of limited time-averaged delta-V capability. By that I mean that no matter what you do (low power mass driver/ion thruster, cold gas, etc) the power limitations will keep the delta-V available for a mission down to modern-day levels. This means missions take a long time, or require a different system to start.<br />And therein lies the real problem with running cold. Even if you have a near-perfect "running cold" stealth, the system is still effectively useless.<br />Situation:<br />Power X detects a vessel of power Y's burning for a while. Then the vessel suddenly disappears. No reactor, no nothing. That's obviously abnormal. They then take the last known position and velocity, and crank in the best delta-Vs available from an undetectable thruster. The result forms a cone. This is where the ship could be. The cone passes right through Power Xs planet. I wonder what's going on?<br />At this point, Power X sends a couple of conventional warships towards the last known location of the stealthed ship. They locate it at close range, and follow it until it realizes that the operation is blown and heads home. <br /><br /><i>The other advantage of that is that any small unmanned sensor platform unlucky enough to detect you just got destroyed by the same beam of heat that it detected. And if a larger ship detected you, you just damaged it enough to be at an advantage in the fight that just broke out</i><br />Not even close. Even a tightly-focusd radiator is not going to form a beam capable of doing damage at significant range. That's not to say I advocate standing right next to the radiators, but it will spread in such a way that by the time it reaches anything that couldn't detect you already, it's not going to damage them. If it could, you'd use it as a weapon. And there are thermo problems with that, not to mention engineering ones.<br /><br />We discussed Q-ships elsewhere, about a year ago. I can't remember which thread, though.Byronhttps://www.blogger.com/profile/07778896782683765138noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-49869947709499395842012-03-21T09:21:58.894-07:002012-03-21T09:21:58.894-07:00Hydroxide:
I think Daniel's objections have no...Hydroxide:<br /><i>I think Daniel's objections have not really been adequately adressed in the discussion. The distance at which something can be detected is rather meaningless - unless you have reason to expect that anything moving in the area is a potential threat. Given the delay in measurement on interplanetary distances, you might not even note a divergence from known "traffic lanes", if such exist at all, until it's already too late. A telescope network is a nice idea, but in reality introduces further delays, because the information has to go from the source to the telescope first, and then from the telescope to the defender, which is a larger distance than straight from the source to the defender.</i><br />I think you're getting your timescales confused. At the detection ranges expected, closing times will be on the order of weeks if not months. Signal processing delays are minimal compared to that. <br /><br /><i>I think the discussion has been too focused on the basic detectability. But stealth is not about the "invisible ships" someone mentione. When an F-117 flies by on a bright day, you can easily see it. When you stand next to its landing strip, you can see it at night. Stealth is not a Klingon cloaking device, which is what the arguments presented really rule out. Stealth is making it hard to identify you as what you are and making it harder to target you. In the end, that is perfectly possible in space. Will there always be a way to detect a ship? Sure. Will there be a way to identify a ship as a threat and target it and take it out IN TIME? Much more difficult. Especially when you're an unsuspecting target either as a sitting duck (by space standards) or travelling on a consistent vector.</i><br />This is exactly the point. If you can cut detection range from 1 light-minute to 10 light-seconds, good for you. However, assuming that you're doing 100 km/s, that's still 8 hours warning. Depending on the mission, that might or might not be significant. For an attack on a major enemy base, it won't matter at all. They'll go to full alert, and you're worse off because of the money spent on the stealth system instead of more ships. For an attack on a minor outpost, it might make a significant difference, as the enemy can't intercept. However, in no case do I see a chance of achieving tactical surprise, which is what people are really looking for.<br /><br /><i>Yes, I can see a whole lot of things if I put up a telescope and take a 30 minutes exposure. In battle, that's just not going to cut it. It is meaningless that I see that there's something moving, unless I can reliably pinpoint the characteristics. To do that, it's not enough that a handful of photons hit my sensors. I need the confidence interval for the deduced characteristics to be reasonably small for them to be meaningful.</i><br />This is only relevant for tactical timescales and ranges. Those are the light-second scales where you will be detected by the fact that you're occluding a couple of stars, if nothing else. And, as noted below, stealth behavior is abnormal, and therefore suspicious. Which will tend to attract attention from whoever you're trying to hide from. Even burning your engine without a beacon will be suspicious. After all, if the burn is going to be detected, hiding your identity is going to be taken as a sign you have something else to hide.Byronhttps://www.blogger.com/profile/07778896782683765138noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-89986468538222988902012-03-02T19:31:15.019-08:002012-03-02T19:31:15.019-08:00Playing catch up:
The main problem with dazzling ...Playing catch up:<br /><br /><i>The main problem with dazzling enemy sensors with a laser is that doing so is an overt act of aggression.</i><br /><br />Uh, well ... yeah. I was thinking of essentially tactical situations, where you are already beyond diplomatic incidents. But zapping sensors is essentially like shooting out searchlights. (Shades of Bogart in 'To Have and Have Not.')<br /><br />Your mention of images only a few pixels across reminds me of an experiment I once did - taking images of naval ships and reducing them to that level. I don't remember my conclusions, but I think they supported your argument.<br /><br />Of course, underlying this are whatever 'natural' differences of configurations between civil and military craft. In the age of sail, or between midcentury airliners and bombers, not that much. For steam era naval craft, a lot. <br /><br />Orbit choice is also a factor in 'stealth' of this sort. Looking like a merchant ship isn't so helpful if you're on a track no merchie would actually take.<br /><br />All of which can plausibly be finessed for desired effect in a work of fiction!Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-29642521885979099132012-02-25T21:08:32.017-08:002012-02-25T21:08:32.017-08:00The main problem with dazzling enemy sensors with ...The main problem with dazzling enemy sensors with a laser is that doing so is an overt act of aggression. Part of stealth could also be concealment of your intentions. Consider commerce raiders: If you're a privateer (a pretty good analogue to a space fairing U-boat, actually) even if your target knows you're a privateer and that you're at the location you are you want them to be unsure about your intentions as long as possible. A convoy won't, for example, take evasive maneuvers until they're sure you're attacking them due to the cost of the reaction mass ect... Another example would be a laserstar or other orbital defense: If you're defending against an approaching armada you want that armada to put off evasive maneuvers for as long as possible so when you make your opening salvo they you have the best chance to hit. Camouflaging your laserstars so it's difficult for the enemy telescopes to tell which direction they're pointing is a great way to do that.<br /><br />Also, there's more to this than signal processing. Consider that at extreme range a ship might only show up as a few pixels on most sensors if that. Just look at most NASA asteroid photographs that are nothing more than a bright cluster of maybe five pixels or so. So, if I'm looking at a ship who's entire hull covers only a handful of pixels how do I tell the difference between sensor noise and a camouflaged hull with regards to that one very dim pixel on the side of the couple bright pixels? I suppose if you watch it for a while you might get a pattern but hey, stalling my enemy for a few minutes is a pretty good use for a can of paint!<br /><br />Even when you consider signal processing it gives you an advantage. Camouflage paint on missile buses, for example, could seriously increase the processing overhead required by the point defense system!<br /><br />Speaking of signal processing the problem with computers as we know them is that they're very reliable in their response to a given stimuli which also means that they're not flexible which is a serious impediment when it comes to analyzing complex images. Consider the performance of current top-of-the-line OCR equipment which isn't very good even when their signal-to-noise ratio and available resolution of the characters is quite a bit better than would be available from a grainy, low resolution, potentially very low contrast sensor image.<br /><br />This is assuming a computer as we understand them today by which I mean they operate by preprogrammed algorithms. True, it's possible that a future computer can learn and reason like we can. There really isn't any reason they can't assuming they're based on a technology that can evolve and adapt new connections like our brains can. The problem with this is that reliability and self-adaptability is a zero sum game because learning requires unorthodoxy and you can't have unorthodoxy in a reliable system. In other words "strong" AIs probably aren't any better than humans at seeing through sensor tricks other than the fact that a "strong" sensor AI might be more practiced at it.<br /><br />I actually would love to talk to you about the possibilities of "strong" AI in the plausible midfuture.<br /><br />I think the biggest advantage of "dazzle" camouflage over "active" stealth like blinding lasers is that being camouflaged doesn't require you to shoot at the enemy. This would be a *huge* advantage for everyone from privateers to blockade runners to navies engaged in a cold war or a tepid peace.<br /><br />I could even see it being used by legitimate merchantmen where the threat of raiders is present due to the difficulty it would give the raiders in setting up an intercept solution.<br /><br />Thoughts?<br /><br />~~<br />SamanthaAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-91713187979071192002012-02-25T18:02:13.981-08:002012-02-25T18:02:13.981-08:00Welcome to another new commenter!
I think the spe...Welcome to another new commenter!<br /><br />I think the specific example of dazzle camouflage, or similar, would probably be defeated by computerized sensors, more patient than the human eye and less prone to visual illusions.<br /><br />But taking it a little more broadly, this is all about 'noise' - creating a welter of irrelevant information that makes it harder to tease out the relevant information.<br /><br />And there's another kind of 'dazzle' that could be relevant - zapping sensors. A very bright light will saturate the sensors, and a much brighter light will burn them out. I don't know the required energy levels, but surely a lot lower than burning through armor, etc.<br /><br />Laser armed ships mutually blinding each other is a scenario that makes things very odd and puzzling!Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-2237417474187884352012-02-25T16:37:44.468-08:002012-02-25T16:37:44.468-08:00Remember that you don't really need spectrogra...Remember that you don't really need spectrography to determine the bearing of a suspect burn using doppler shifts when you can point a nice, big optical telescope at the area you saw the burn and note the direction the ship is pointing.<br /><br />For this reason I envision that future space navies might employ something similar to WWI "dazzler" camouflage. It was dramatic and erratic counter-painting designed to break the contours of the ship to make it more difficult to identify against the background and, more importantly for our purposes, to make it more difficult to determine the ship's class, bearing, and speed.<br /><br />I could see a future ship having sharp black-and-white counter-painting on the hull, oddly distributed insulation around the reactor, oddly aligned or oddly shaped thermal radiators (think NASA AD-1 only with radiators instead of a wing), and panels around the engine exhaust to occlude enemy sensors to give the burn a deceptive shape from the side.<br /><br />Of course, these things would have the disadvantage of throwing any pretense of being a merchant ship out the window. Perhaps future Q-ships would use things like heaters on the hull of their fake freighter and cloth skins for the counter-painting that could be jettisoned as they approach the shipping lanes.<br /><br />Here's a picture of WWI "dazzle" cameo:<br />http://en.wikipedia.org/wiki/File:SS_Empress_of_Russia_1918.jpg<br /><br />Here's a picture of a NASA AD-1:<br />https://en.wikipedia.org/wiki/File:AD-1_ObliqueWing_60deg_19800701.jpg<br /><br />Thoughts?<br /><br />~~<br />SamanthaAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-69746127540706806502012-02-18T09:04:58.008-08:002012-02-18T09:04:58.008-08:00No dispute, really, on these points!
But discussi...No dispute, really, on these points!<br /><br />But discussions about stealth in space generally start from the intuitive sense that space is night writ big, and thus that sneaking up on someone is inherently easy. When the contrary is pointed out, people put huge efforts into Rube Goldberg-ish ways to make ships invisible.<br /><br />That is the context of 'everyone sees everything' as an aphorism.<br /><br />Exploiting <i>uncertainty</i> is a very different matter, and far more fruitful.Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-79591793602416469832012-02-17T13:39:24.863-08:002012-02-17T13:39:24.863-08:00Rick, the point that is missed in posts such as th...Rick, the point that is missed in posts such as the one on projectrho.com that you linked is that "everyone sees everything" is meaningless for conflicts. Yes, I can see a whole lot of things if I put up a telescope and take a 30 minutes exposure. In battle, that's just not going to cut it. It is meaningless that I see that there's something moving, unless I can reliably pinpoint the characteristics. To do that, it's not enough that a handful of photons hit my sensors. I need the confidence interval for the deduced characteristics to be reasonably small for them to be meaningful.<br /><br />Automated scans do a lot. They're not omnipotent, however. And at the end of things, no one can beat statistics. Statistics however says that I'll always have a confidence interval, and the less events I have, the broader it will be. As such, any reasonable effort to reduce emissions WILL help in clouding the character of what's there in terms of a per-time basis. It will prolong the period of observation until you can actually make sense of what's moving there and separate noise from signal.<br /><br />"Seeing" and "characterizing" something are two very different things. When the realization that you're looking at where an enemy was 8 minutes ago hits you at the same time as his thermonuclear warhead, you might just as well not have bothered....Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-68586051744189859812012-02-15T19:08:16.586-08:002012-02-15T19:08:16.586-08:00Apologies to Gareth for not noticing his comment f...Apologies to Gareth for not noticing his comment for so long! <br /><br />And welcome to all the new commenters in this thread!<br /><br />Cabin temp is often used as a baseline for skin temperature because over long travel times it will be hard to keep the skin much colder. Especially if the ship is near 1 AU (or equivalent distance from other stars), which is where human habitable planets tend to congregate.<br /><br />Exhaust will cool rapidly, but it does start out hot! Generally I think it's a fair bet that at least a few percent of waste energy will be in radiative form. And even 1 percent only reduces detection range / increases aperture for a given range by a factor of 10.<br /><br />Cold gas is very hard to detect, but it has very limited specific impulse (~30 seconds at room temp, less at lower temps). So the deflection available is limited.<br /><br />Having said on this, hydroxide touches on the core point of this post, that 'stealth' is not identical to invisibility. Knowing the trajectory, size, and mass of a spacecraft does not tell you its intentions.<br /><br />'Everyone sees everything' should be understood as a general warning that invisibility-style stealth is not easily achievable in space. Which is not intuitive to most of us, starting out, because after all we see space as dark, and we learn at an early age that it is hard to see things in the dark!Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-1951967497302965132012-02-14T18:05:22.958-08:002012-02-14T18:05:22.958-08:00Forgive me if this has already been talked about, ...Forgive me if this has already been talked about, but a cold gas CO2 thruster would not have much of a heat sig, and there does not appear to be a theoretical (though there certainly is a practical) problem with radiating all your heat into a .05 degree beam while not using your main (bright) engines. Even then you could radiate only once a day for thirty seconds at a time. As I understand it, the *only* heat you have to radiate is the heat generated by the life support equipment and by the (shut down) reactor. <br /><br />That much heat is sufficiently small that you could put that in an on-board heat sink, and radiate it off quickly, and into a very small volume of space. And then change direction very slightly using your CO2 jets to avoid being hit by the nearby battleship on the off chance that you are detected.<br /><br />The other advantage of that is that any small unmanned sensor platform unlucky enough to detect you just got destroyed by the same beam of heat that it detected. And if a larger ship detected you, you just damaged it enough to be at an advantage in the fight that just broke out :)Rocketeernoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-73696695738272053392012-02-06T09:08:41.593-08:002012-02-06T09:08:41.593-08:00I wonder how easy it would actually separate an IR...I wonder how easy it would actually separate an IR decoy "lamp" drone from an actual warship. I've heard the usual argument about emission lines, but that usually involves doing spectrography on it, something that takes <i>hours</i> in real life to get the proper exposure. <br /><br />A smart enemy would do engine burns only for a couple of minutes at a time, and you'd never be the wiser. You'd have very little ability to tell whether those interesting pixels of IR that your telescopes picked up are attacking spaceships or decoy emitter drones.Bretthttps://www.blogger.com/profile/05741738070067590221noreply@blogger.com