Thampsan wrote:

We don't know how quickly an antimatter factory can produce antimatter do we?

It'll depend on the size, method and capability of the factory. Small colliders might put out a gram a year or less... which is fine for emergency farcaster production, but poor for fueling ships. An antimatter scoop orbiting within Jupiter or Earth's magnetosphere can probably "produce" a lot more.

Anti-matter gets bigger in space.

nezumi.hebereke wrote:

Anti-matter gets bigger in space.

That depends. Antimatter is basically the same as matter, and exhibits the same properties in inverse (positrons act like electrons, but are positively charged, antiprotons act like protons, but are negatively charged). As such, antimatter in any given form will exhibit the same properties as matter in the same form. Certain antimatter solids will likely not expand in space, anymore so than normal solids. Antimatter gases and free-floating particles are a different matter.

valen wrote:

I don't remember that section about destroyers from the main book, but I definitely got the impression from Sunward that antimatter was an experimental starship fuel and still in development.

I wouldn't say experimental... I'd say expensive. Antimatter is hard to produce, and harder to contain. Even a slight leak in the containment unit will cause a catastrophic failure and devastating damage... so containment units are likely to cost a lot to produce. 1 metric ton of antimatter, when annihilated with matter, will produce 1.8 * 10^20 joules of energy... which is the equivalent of 45,000 megatons of TNT. The smallest ships powered by antimatter carry 6 tons on a full tank. You can only imagine how scary it must be to be sitting on that much potentially-volatile power, hence the reason that precautions are very critical to the crews of such ships.

Is the text read as the destroyer (one particular individual) is [b]one of the largest [/b]military spacecraft in common use, Or that the "destroyer" type of spacecraft is one of the largest spacecraft type in common use. Cause if a individual large destroyer carries that much, the rest may not -since they are "smaller". The other way to look at it; Is that Jovians get the rest of the ridiculous large tonnage of antimatter somewhere else. Either they produce it or someone or something are supplying them with rr. Produced somewhere else and not on mercury. I imagine the Jovians also create antimatter at several other sites for example near Jupiter. Remembering another thread. That is somewhat relevant. http://www.eclipsephase.com/secret-assets-jovian-junta

Arenamontanus wrote:

[i]from thread Re: Secret assets of Jovian Junta [/i] Personally I would suspect the JJ has plenty of nasties hidden, but knows that their real purpose is to keep everybody nervous about finding out the hard way whether it is a big bluff or a serious threat. The real strength lies in the more traditional defences.

Arenamontanus wrote:

[i]from thread Re: Secret assets of Jovian Junta [/i] The Jupiter system likely has a lot of energy, and with the right equipment you can beam it to nearby destinations. Imagine putting a few superconducting loops into the Jupiter magnetosphere, powering large phased arrays of laser emitters. Makes a great energy distribution system, propulsion (vaporise ice or power VASIMIR externally)... and a giant beam weapon network.

Imagine that the Jovian have these "secret" Jupiter magnetosphere superconducting loops & even the "secret" arrays of laser emitter. When not having acceptable targets to light up; the unused & excess energy generated is instead used to produce antimatter. Storing the energy to waste targets in the future, instead of just wasting energy. Perhaps it exist better ways of storing or using the excess energy -but the antimatter production companies pitch got the military approval & contract. Does the Jupiter magneto-spheric loops, and Jovian non mercurial factories & secret benefactors generate the yearly production need ( 712 500+ factories?) Or are the Jovians inaugurating their weapons of mass-destruction to scare off potential attackers. I would actually select several alternatives that look to be mutual exclusive - together. Jovians doesn't have enough antimatter, They still have large fleets of destroyers, but many of them are "fakes" or "decoys". The few "real" ships have enough teeth to pass around, and a fake fleet give the "real & teethed" the visual respect they should have. Propaganda & deception strategies/tactics have since antiquity, used obsolete & regular ships, straw, carts & vehicles to fake warships, soldiers, chariots & other war-machines.

Slith wrote:

Well, I think the most logical explanation is that the writers accidentally the amount of antimatter by an order of magnitude. Or two. 150kg or 15kg makes more sense than 150 tons.

150 tons sounds reasonable when you are talking about what is likely to be the biggest show-of-force vehicle in the setting. It is going to utilize that tonnage for powering its systems, for fueling its fighters, and for loading its torpedoes. More importantly, this ship is probably going to be staying on tour for extended periods of time... years even. I believe the destroyer is the EP equivalent to today's supercarriers... they are the flagships of the most powerful and prominent governments in the setting.

First off, space craft are not sea vessels, and as such you cannot necessarily expect the sea designations to be equivalent to the space designations. As a similar example to this, carriers in EP haul cargo, not fighters. In a modern analog, space shuttles are not even similar to public or air shuttles, nor are space stations similar to air, power, or transit stations. Besides, the destroyer's armament places it well above what a naval destroyer is equipped with, since it also has its own fighter squadron. If anything, the closest naval analog would be the currently-in-planning [url=http://en.wikipedia.org/wiki/Zumwalt_class_destroyer]Zumwalt class destroyer[/url], which is intended to overlap with both the naval destroyer and battleship class and is more suited to multiple mission roles.

It's even worse when you read page 349 "Anti-matter rockets work mixing small amounts of anti-matter into the hydrogen fuel, producing enormous amounts of energy and an exceptionally fast and powerful exhaust. These rockets typically carry a heavily shielded magnetically contained anti-matter storage vessel carrying a mass of anti-matter equal to 1% of the mass of the hydrogen fuel used by the rocket.The magnetic containment vessels needed to safely contain antimatter usually weight at least 10 times the mass of the antimatter used." So that would mean 15000 tons of hydrogen fuel together with 150 tons of antimatter. 150 tons of hydrogen fuel and 1.5 ton of antimatter would make more sense perhaps(the destroyer is mentioend as having 2000 ton containment device so between 1,5 to 2.0 tons) The courier too has large amounts of antimatter "Anti-matter drive fast couriers are vessels designed for this specific purpose. This vessel can travel from Venus to Mars in a week and from Mars to Jupiter in a month. The fast courier is the swiftest vessels currently made and is able to reach at much as one half of one percent of the speed of light. To manage this, this spacecraft must also carry 6 tons of antimatter in a 100 ton magnetic containment vessel. In an emergency, this containment facility can be jettisoned." So something needs to be corrected. Either they have less antimatter, or the factories produce more of it.Or..... the Factors sell antimatter in exchange for Flat toddlers. But do mind that comparing modern navy to future one might be flawed. In WW2 USA, Britain had tens of thousands of planes for example. Improved technology reduced that number. We can't compare number of ships o USA navy today to ships in Jovian Junta. They might have much less with far much more power and abilities.

Also note that there is enormous potential for energy generation in Jovian system: http://www.eclipsephase.com/using-ios-flux-tube-energy-source

valen wrote:

What your talking about is a chain-reaction. Something that AM weapons want to maximize and AM fuel tanks want to minimize. What this really means (listen up budding mega-terrorists) derelict military spacecraft with good procedures and good fuel tanks will likely contain recoverable amounts of AM that can be turned to nefarious purposes by those brave enough to recover them...

Nukes are much nicer in this respect: to get a nuclear chain reaction you need to get a lot of pieces together in the right way. A broken nuke is not likely to do much damage (besides being pretty radioactive or containing some nasty explosives, of course). A broken AM warhead on the other hand *will* go boom. With nanotech I think one can tamper-proof nukes amazingly well. Nanoexplosives that refuse to explode unless given the right codes, and will explode in a really useless way if tampered with. Tamper-proofing AM is mostly about preventing it from going off prematurely. So from a military standpoint nukes are much more likeable - it is just tough getting the transuranic elements for the fission triggers in the outer system (...hmm, AM triggers ought to work, but then you get a bomb almost as bad as a pure AM bomb). I think most warships mainly use AM for energy storage and propulsion. Might be great for small, strongly accelerating missiles though - they can use the AM both for propulsion and as a complement to the warhead.

Maybe I'm a bit off topic but I've been reading up on Antimatter containment and came across this on the Wiki. "The second problem is the containment of antimatter. Antimatter annihilates with regular matter on contact, so it would be necessary to prevent contact, for example by producing antimatter in the form of solid charged or magnetized particles, and suspending them using electromagnetic fields in near-perfect vacuum. Another, more hypothetical method is the storage of antiprotons inside fullerenes. The negatively charged antiprotons would repel the electron cloud around the sphere of carbon, so they could not get near enough to the normal protons to annihilate with them." Now that first part anyone interested in Sci-fi would be sure to know, the magnetic bottle theory has been around for a long time. My interest is in the second one: Using the fullerenes's (sub?)atomic geometry as a method of containment. We all know fullerenes are almost ubiquitous in EP so *IF* it would work that could be a more stable way of storing Antimatter long term instead of relying on electro-magnetism (which would need a secondary source of power). I was thinking about some fullerene antimatter storage cells on derelict ships and habitat as a possible lure/payoff for a salvage operation. Since it's hard to come by it could get some major Creds or Rep.

Slith wrote:

Well, I think the most logical explanation is that the writers accidentally the amount of antimatter by an order of magnitude. Or two. 150kg or 15kg makes more sense than 150 tons.

I ran the numbers on the ships when I designed them, and 150 tons is correct. The total mass of a destroyer is around 40,000 tons, a bit less than half that mass is fuel and reaction mass (15,000 tons), and 1% of that is anti-matter. Yes, that's a truly vast amount of anti-matter. However, if you want to move a spacecraft the size of an aircraft carrier or a supertanker from Mars to Jupiter in a month, and still have plenty of fuel and reaction mass left over, you need lots of antimatter.

Extrasolar Angel wrote:

And where from do they get the anti-matter ?

My suggestion would be to change the line in Sunward from "These factories produce around a kilo of antimatter each month" to "These factories produce around a ton of antimatter each month", if you have a few dozen factories, then fueling a few destroyers becomes possible, but you'd need to use those ships quite sparingly, which makes sense. Change the figure to "These factories produce around ten tons of antimatter each month" and anti-matter scarcity vanishes. I prefer the option of one ton/month per factory.

jsnead wrote:

Extrasolar Angel wrote:

And where from do they get the anti-matter ?

My suggestion would be to change the line in Sunward from "These factories produce around a kilo of antimatter each month" to "These factories produce around a ton of antimatter each month", if you have a few dozen factories, then fueling a few destroyers becomes possible, but you'd need to use those ships quite sparingly, which makes sense. Change the figure to "These factories produce around ten tons of antimatter each month" and anti-matter scarcity vanishes. I prefer the option of one ton/month per factory.

Sometimes it pays to come into a thread late. :) I'll be using those revised manufacturing numbers in my campaign.

Arghhh, my brain, too much numbers ;p Since you are so good with them, as an offtopic-do you have any idea what percentage of light speed can the ships in EP achieve?

Thinking a bit about naval strategy: What kind of weapons are being fielded, can they be defended against, and what kind of missions will the ship be sent on? If the weapons are hard to defend against the ship has to be stealthy and hard to hit. Looking at the core book description of the destroyer having railguns, nuclear and HE missiles, point defense lasers and fighters, tells us a few things: Railgun projectiles currently move with velocities a few kilometres per second. This is comparable to normal inter-spacecraft velocity differences: just putting a pebble in the way of your enemy will do plenty of damage on its own. It also means that it will be hard to hit an enemy that is manoeuvring since by the time the projectile reaches where it was, it will have had plenty of time to go somewhere else. Even spamming space with a cloud will be hard since the volume where the ship could go is very large. If the distance to the enemy is d, it moves with velocity v like the projectiles and can accelerate up to a km/s^2, then the total volume where it could go is .5*pi*a^3*d^6/(3*v^6) - for d=1000 km, v=10 km/s and a=5 G I get a volume of 62 million km^3. [I assume the projectile traverses the distance in time d/v, during which the enemy has accelerated up to .5*a*(d/v)^2 away from the extrapolated path.] If railgun projectiles go much faster, then things cheer up for the attacker. A 100 km/s projectile gives the enemy ship just 62 km^3 to hide in, and a 1000 km/s projectile just 62,000 m^3 (and they are going to intersect the volume too, not just sample a single point). Increased acceleration tolerance of the enemy of course equalizes things a bit, but the deciding thing is the relative distance between the ships - you can't hit anybody beyond a certain radius - and the speed of the railgun projectiles. Note that habitats are sitting ducks here, possible to hit almost from anywhere with a high-accuracy shot. The probability of hitting a ship with cross-section area A will be ~4*v^4*A/(pi*d^4*a^2). [I assume the projectile will hit somewhere in a circular cross section of area pi*(.5*a*(d/v)^2)^2, and if it hits within a particular area A it hits. ] Assuming A=0.1x0.1 km for an impressive Destroyer, with the above 10 km/s projectile the chance to hit is just 10^-8. For 100 km/s it is 0.0005, and for 1000 km/s you are pretty certain to hit. If the ship is just 10x10 meters, then even the superfast projectile is back at 5% chance again. This makes fighters sensible - they can likely keep a small cross section and high acceleration. Also note that if the distance is just 100 km the hit chance goes up a lot - you want to shoot close to the enemy, but not be close to him. The kinetic energy from a 10 km/s 1 kg impact is 50 MJ. At this point the kinetic energy starts to become bigger than any (chemically) explosive force you can put in the projectile. 100 km/s is 5 GJ (about one ton of TNT) and 1000 km/s is 500 GJ (100 tons of TNT). They will penetrate to a distance about equal to the projectile length times the ratio of projectile to armour density (Newton's penetration law). This is actually an interesting problem: you want to deposit all this energy inside the ship, so you want to tune the projectile length to its armour. Too heavy projectiles and they go straight through the ship - sometimes having no armour at all the smart strategy (just hope they do not hit your antimatter). Too light projectiles and all energy gets deposited outside the armour. Since the lasers are point defences rather than main armaments (with v=300,000 km/s, you would be able to hit anybody visible within at least a lightsecond), I think we can deduce that it is hard to project a sufficiently high energy beam far enough, but that it can become tough on short distance. I expect railgun projectiles are hard to hit, but missiles are the likely main targets. Missiles can presumably accelerate at least a few 100 G. They can also adjust their course to get close to ship targets and then launch something nasty. However, they likely need to get reasonably close to do this given the above discussion. They likely lack the energy to launch railgun projectiles, but instead launch a bunch of warheads or fire a one-short laser. So they will always be vulnerable to point defences, which will successfully defend the ship if they disable the missile before it detonates. Conversely, if it detonates then it can deliver far more oomph to the enemy than a railgun projectile. There is essentially no way a ship can handle running into a point-blank nuclear fireball or piece of antimatter. Together, this seems to imply that

1. Missiles are the real ship killers, and much effort will go into detecting, avoiding and disabling enemy missiles.
2. railguns are useful against certain targets, but either require enormous velocity or rather short distance fighting.
3. Fighters make sense since you want to bring sensors, railguns and missiles close to the enemy while staying far away yourself.
4. Armour might mainly be against railgun impacts (and other debris) rather than missiles, and it might be better to have a ship that is resilient to a few impacts than have a heavy armour that brings down your acceleration.
5. Railguns make sense against fighters, since they can not accelerate as much as missiles but will be close to you.
6. Maintaining distance is a good way of avoiding to be hit. Hence, you want to be faster than your enemy (and stealthy). Second best is having a big acceleration, tied with a small area.

If I were a naval planner for the Titanian Commonwealth or the Planetary Consortium, I would likely start by deciding that the major naval ships would not have any space for biomorphs onboard, and quite likely not much of synthmorphs either. The sheer amount of space and mass that has to be spent on keeping a biomorph alive is large, and they have to be protected from accelerations, temperature, radiation, you name it. An infomorph crew and tiny repair synthmorphs/nanoswarms would work much better. This way the ship could be made as stealthy as possible (by keeping a low temperature), as small as possible, and able to handle extreme accelerations. My idea for a major high-tech naval ship would probably be something like a tiny Borg cube, dropping off fighters and modules in a large cloud while staying hidden. Armour would be sacrificed for redundancy. The Jovian Junta, having to have biomorphs onboard, cannot do as heavy accelerations and will be forced to have bigger ships. So they can add lots of armour to withstand railgun fire, and lots of point defences plus sensors to catch any incoming missiles. To have a chance at hurting the enemy they need plenty of fighters, again pretty heavily armoured/defended since they cannot be too nimble (expendable pilots cannot fix the lack of acceleration tolerance: a pulped kamikaze pilot is useless). To my mind, that suggests that they would really want to get their long-distance weapons better: either very fast railguns, or *powerful* lasers. [doff's my admiral's hat folded from newspaper]

hi hi Fighters can make a certain amount of sense with infomorphs as pilots, because you're going to need to be pushing the acceleration as hard as you can to evade point defense fire at that point. It is not such a big deal for Destroyers though, since their maximum maneuvering speed is a fraction of a G anyway. Railgun rounds aren't going to be any harder to detect than missiles, although they'll probably have a smaller cross section which would make them harder to achieve a firing solution on. The only way I can see railgun rounds being stealthy is if they are fired out of a massive refrigerated sabot, but I don't know if super science would make that even remotely feasible. There's not really any way to be stealthy in space, you may be able to blind someone's targeting with large amounts of ECM, but they're going to have a reasonable knowledge of where you are. It would be like trying to hide a nuclear explosion in a freezer... heck, for ships that are powered by fusion, it [b]IS[/b] trying to hide a nuclear explosion in a freezer. That being said, the suggestion in the book about making space combat a plot device rather than a combat simulation makes a lot of sense. Space combat is very likely to be brutal with massive losses on every side of a given conflict unless one side greatly outnumbers the other. Spaceships, just by the nature of their propulsion systems are weapons of mass destruction even before you strap weapons onboard. Also, while destroyers are one of the biggest ships, I would bet there are a number of patrol ships out there to keep space traffic in line. Don't need anyone lining themselves up for a relativistic attack on your colony.

Why would railguns produce significant amounts of heat? There's no real friction. Are you referring to the heat generated from the electromagnets? How effectively would that transfer to the projectile itself, since they aren't actually touching? I gotta admit, it seems like the only reason for big capital ships like this would be attacking heavily guarded stations, or serving as weapons platforms. I can't see there being much of a call for attacking ships in transit.

root@Antimatter Inconsistency One good reason for a capital ship like this is habitat bombardment. Also, terraforming, in a rather slapdash way.

Slith wrote:

Quote:

Fighters make sense since you want to bring sensors, railguns and missiles close to the enemy while staying far away yourself.

Fighters never make sense. Drones, drones make more sense. Not fighters.

What's the difference between a drone and a fighter in this setting? The fighters in the core book are specifically designed to be piloted by AIs or infomorphs, so they don't require any sort of pilots with bodies. Instead, they're highly mobile, reusable laser, railgun, and missile platforms. They're a hell of a lot more maneuverable than a capital ship and can accelerate much faster. Yes, missiles might be cheaper, but the fact that the fighters are reusable means the capital ship has them available for mutliple engagements in a short period of time, w/o having to fab up more of them (which takes both time and resources). If the destroyer (perhaps not the best name) had unlimited mass and no risk of multiple engagements in a short period of time, then disposable drones might work better, but if a ship is a long way from home and facing multiple hostile encounters, then there's a lot to be said for recoverable drones or fighters, or whatever you want to call them.

Slith wrote:

Fighters never make sense. Drones, drones make more sense. Not fighters. Because when you look at it, there's no benefit to a fighter. You're designing something that flies to a target, shoots it, then flies back. That requires doubling the amount of fuel it carries. For what benefit? The mothership that launched the fighter can reach the target even faster, carries more supplies, has more endurance, and bigger guns. Instead of fighters, you could launch missiles that mass less, take up less space and don't need anything more than a computer program to guide themselves into a target. Hell, the missiles don't even need warheads because they can kill through sheer kinetic energy. It's not at all accurate to compare it to wet navies vs aircraft because the two operate in different environments. Space fighters to space destroyers is like speedboats to naval destroyers. Space is its own unique environment, and the conventions that hold on land, sea and air do not hold true for space. Thinking and applying the exact same tactics and strategies from naval combat to space combat is going to be making the same types of mistakes that were made in WWI with cavalry and infantry charges into massed artillery and machinegun fire.

Actually, there's quite a bit of functionality in a "fighter" class of space craft. For one thing, a missile is limited in capacity: singular purpose (destroy), singular objective (can only destroy one thing). Fighters can be used for multiple purposes, and achieve multiple objectives. Furthermore, the primary advantage to missiles in our day and age are the fact that the usage and loss of a missile does not include the loss of a soldier... whereas spent fighters generally mean spent soldiers respectively. This is not the case in a world with AI and forks, where a spent fighter may very well be the equivalent of a spent missile. In fact, fighters may very well be equally capable of fulfilling the role of missiles; a damaged fighter driving itself kamikaze-style into a target after it has been rendered incapable of a return trip to dock, expending its remaining antimatter fuel as a weapon payload.

root@Antimatter Inconsistency> I like your grizzled infomorph fighter concept. If I were designing a fighter squad, I would not want to have alpha forks of the same infomorph on all of my fighters, instead I would load as many as possible onto each fighter and choose which one gets control of which fighter for which mission. The prime forks would be constantly training and updating the forks, up to every second or so leading up to an actual engagement. The rapid updates are to reduce the temporal distance between the prime and the alpha forks so destroyed fighters can merge back with the prime and deliver up to the second information about the battlefront without ripping the prime's mind to shreds. Fighters have to be chosen for mental resilience and flexibility, as well as somatic and tactical excellence. Retirement would occur when the mental health of the fighter has deteriorated too much to trust them with a few tons of murder equipment. The remerging of forks would be a primary strategic consideration when choosing between fabbed missiles and fighters, as one can bring back intelligence. Having many different primes helps reduce the stress on each prime, and creates a more heterogeneous XP pool to work from for future training. You can say the missiles can do the same, but I think it would be hard to find volunteers to explode over and over and over again. They would go insane far too quickly to be economically worth while. Although, I would guess you could find infomorphs from Earth who were willing to be a missile jockey for a chance to be re-instantiated.