Ortillery - feasible?

[adam_grif]

Alrighty then. Some questions:

- How powerful does a laser need to be in order to kill a tank from an orbit of your choosing?
- Could an orbital laser deal with the waste heat necessary for it to do some tank slaying?
- How massive would it need to be, and what kind of power generation would it need?

It goes without saying that such things can't be built with contemporary technology. And I have a feeling that if it's killing tanks at ground level, it's going to have to be stupendously powerful and, thanks to the atmosphere, less of a surgical weapon than you might like (diffraction etc). Of course, you don't have to get nearly that powerful to kill ICBM's in high atmosphere, or other satellites.

I don't have any realistic hopes about this sort of thing, but dammit, I want my orbital death rays, you know?

Moving to kinetics, of the guided reentry variety (i.e. Rods From Gods).

- What sort of times are we looking at from a weapon being targeted to it making impact?
- Given that every joule of energy that is delivered to the target must be payed for by the launching vehicle sending them up in the first place, could it ever be cost effective?
- Are these sorts of things going to do any kind of wide-scale destruction, or are they going to punch a hole into the ground and just keep going for a while?

With this one, my money is on "totally infeasible without significant reductions in the cost of STO transport."

And as an aside - particle beams?

[cosmicalstorm]

I imagine it would be a lot easier to make a tank hot enough for the crew to be immobilized than it would be to melt or vaporize it.

[Sea Skimmer]

Alrighty then. Some questions:

- How powerful does a laser need to be in order to kill a tank from an orbit of your choosing?

That would depend on how dead you want the tank, how high the orbit is, how close the orbit comes to passing directly over the tank and how long of a dwell time is acceptable. But low megawatt range like ABL ought to be enough to cause extensive damage to external components like the gun barrel and roadwheels. Ideally a laser would pass directly overhead and burn a quick cut across the gun barrel and then burn down through the engine grill until the engine burns. Defeating the main armor would be very hard from orbit because even if you had enough firepower to do it, the angle of attack keeps changing at 6,500+mph, so its not like you can burn a hole straight through. You would end up heating up a much wider area and this is generally a bad way to try to kill a tank since even if you melt through the armor you won't cause much interior damage.

- Could an orbital laser deal with the waste heat necessary for it to do some tank slaying?

The same way anything else deals with waste heat, radiators.

- How massive would it need to be, and what kind of power generation would it need?

Right now it would have to be the size of the Airborne Laser, only even bigger for all the support equipment and radiator arrays. Power could easily be solar since it would be a chemical laser. Break out the Saturn V to orbit the sucker, and don't forget the need for support missions to keep sending up more laser fuel. Its just like inflight refueling only ten thousand times more expensive!

It goes without saying that such things can't be built with contemporary technology.

No it doesn't. We could have this right now if we felt like building 10 billion dollar satellites. It just wouldn't be a very satisfactory system because it was chemically powered.

Moving to kinetics, of the guided reentry variety (i.e. Rods From Gods).

- What sort of times are we looking at from a weapon being targeted to it making impact?

Depends on the orbit height and required cross range to the target. It could easily be 2-3 hours even for a satellite which was very close to the proper orbit. Radical shifts of orbit, fuel allowing, could take several days.

- Given that every joule of energy that is delivered to the target must be payed for by the launching vehicle sending them up in the first place, could it ever be cost effective?

Unlikely except for a coordinated orbit sneak attack scenario in which the satellites fall out of orbit in the first minutes of the war. I suggest 150 megaton warheads since this is a good way to start a nuclear war anyway. Future breakthroughs in space launch like hypersonic air launch might make the economics work a lot better, but such high speed air breathing platforms would yet further reduce any possible need for orbit to surface weapons. Otherwise it makes much more sense to just shoot a conventional ICBM at the enemy, which will in fact arrive faster then many orbital weapons. An Atlas missile needs IIRC 43 minutes to reach 8,000 miles.

- Are these sorts of things going to do any kind of wide-scale destruction, or are they going to punch a hole into the ground and just keep going for a while?

Punch a hole in the ground, but nothing stops the satellite from being designed to spread a cone of shrapnel as it comes down to hit area targets.

And as an aside - particle beams?

Absurdly vague term. A rifle could be considered a particle beam.

[Isolder74]

ION CANNON READY!


While it works great in sci-fi a big problem with space-based weapons is dual. First you need to power the weapon which solar cells is not going to be enough. Getting the reactor required into orbit will be expensive and technically complicated. Second is the energy weapons itself which will be heavy as well and require similar expense to get into orbit.

Also you would need more then one just for it to be strategically viable. The space-based weapon can only fire on a line of sight location on the planet below where it is orbiting.

[Isolder74]

First you need to power the weapon which solar cells is not going to be enough.

Why not?

The massive array required to start with. We are talking MEGAWATTS of required power here. A smaller array would require long recharge times in order to build up the power required. A build in reactor would be the only reliable way to get the required power on demand.

[Admiral Valdemar]

The massive array required to start with. We are talking MEGAWATTS of required power here.

There's serious commercial plans out to make that happen within the decade.

Besides, any kind of reactor would have similar mass to the solar panels. It'd take about a ton of solar panel to get a megawatt, and it'd take about a ton of fission reactor to do the same.

A smaller array would require long recharge times in order to build up the power required.

This is probably required anyway, due to the beam requiring lots of power up front, and the weapon won't be firing continuously, so you'd have lots of time to charge it.

It also makes for a larger target, but then this all assumes no other party has the means to perform an ASAT kill, or that the satellite is able to take out any attempts to kill it. In any case, massive solar arrays are vulnerable to more than human attacks, and so should be avoided. A more compact satellite using a reactor would be a better configuration, and small fission reactors have already been used in space. Or one could have cheaper mirror satellites and use a ground based system to fire up to the orbiting constellation. At least then you don't need the power supply being built in space, and if a satellite is lost, it's a far less costly affair to replace than a whole new weapon system.

As for particle beams, to mission kill anything on Earth, you'd need a CPB, but that means blooming occurs in space, so the weapon would need to be LEO and thus easier to hit. Lasers would be far more useful, or railgun slugs for a kinetic kill (remember to allow for Newton's third law).

[Korvan]

Sea Skimmer mentioned chemical lasers, one advantage of using these is that you can get rid of a lot of the waste heat by simply venting the reaction products into space. Also, as I remember it (from a debate years ago on Reagan's StarWars) you can get a very energetic laser from reacting Hydrogen and Florine. However,the wavelength of the beam is absorbed by the atmosphere. But by substituting deuterium, you get a wavelength to which the atmosphere is completely transparent.

This brings up another problem tho, the wavelengths of practical chemical lasers that can pass unhindered through the atmosphere are limited and not exactly a big secret. So if the tank is coated by a material that scatters those wavelengths, it is effectively protected from orbital lasers(chemical ones at least).

[Admiral Valdemar]

For taking out armour, you're probably better using kinetic kill methods, rather than DEWs. Unless you have an X-ray laser, it's just easier to use that energy to throw a slug at a good speed in the general area of the tank. The atmosphere would also make it have one hell of a thermal effect too, provided the slug isn't so small that it burns up and detonates before it makes contact.

[Sarevok]

Why bother targeting tanks when you can lase the fuel trucks ? A massive 50 ton armored vehicle is not going anywhere attacking without its considerable refueling support.

[PaperJack]

Personally, I'd go with much smaller, 'suicide-bomber' satellites.
When you point a target, they start speeding towards it and hopefully impact the target before it moves.
Or, you know, you could use long-range rockets.

[Admiral Valdemar]

Quite. Using ortillery to take out individual armoured units is a bit... overkill. You could use the laser or railgun to wipe out the division before it even landed on your shores, or if it's already in your neighbourhood, you could take out any forward command bases or logistic trains with impunity. Tanks don't last very long with no fuel or ammo and spares coming through.

If you were going to be truly sick, you could use a lower power beam to just incinerate the living quarters with said occupants in. Far less effort than vaporising armour.

[Sarevok]

One juicy and cost effective target would be those powerful and expensive air defense radars. They are easy to detect by their emissions and their antennae are fragile.

Another target be aircraft parked in the open.. A satellite passing overhead could turn a runway of full of planes into sitting ducks that cant take off anymore.

[Isolder74]

The massive array required to start with. We are talking MEGAWATTS of required power here.

There's serious commercial plans out to make that happen within the decade.

Besides, any kind of reactor would have similar mass to the solar panels. It'd take about a ton of solar panel to get a megawatt, and it'd take about a ton of fission reactor to do the same.

A smaller array would require long recharge times in order to build up the power required.

This is probably required anyway, due to the beam requiring lots of power up front, and the weapon won't be firing continuously, so you'd have lots of time to charge it.

It also makes for a larger target, but then this all assumes no other party has the means to perform an ASAT kill, or that the satellite is able to take out any attempts to kill it. In any case, massive solar arrays are vulnerable to more than human attacks, and so should be avoided. A more compact satellite using a reactor would be a better configuration, and small fission reactors have already been used in space. Or one could have cheaper mirror satellites and use a ground based system to fire up to the orbiting constellation. At least then you don't need the power supply being built in space, and if a satellite is lost, it's a far less costly affair to replace than a whole new weapon system.

As for particle beams, to mission kill anything on Earth, you'd need a CPB, but that means blooming occurs in space, so the weapon would need to be LEO and thus easier to hit. Lasers would be far more useful, or railgun slugs for a kinetic kill (remember to allow for Newton's third law).

Not only that but we aren't talking about 1 or 2 Megawatts of power 10's 20's or up to 100's of megawatts required. The Solar array to make 1 megawatt is big enough already now add to that the array of batteries and capacitors required to charge up to the amounts you'd need to do any real damage to a target on the ground.

A fission reactor would take up far less space and require less mass then would the Solar array required to get the needed power. The more surface area a satellite has the more it will be hit by and damaged by space debris. You can't discount this problem. A 10 Megawatt nuclear reactor would be much more practical then even a Solar Array of the same power output. The unit can have solar cells to power it's targeting systems with much more practicality then trying to power the weapon itself.

[Sarevok]

Bear in mind solar panels are much more efficient in space than Earth. You can use smaller panels to generate same amount of electrical power in Earth orbit. Besides you dont need to run the laser directly from solar. Submarine style large batteries should be able to easily store and supply megawatts of power needed for a laser pulse. In between shots the laser can cool down and recharge.

[Mr Bean]

Lasers off lots of advantages but you simply can't beat Rods from God for cheap methods of killing things on Earth. Lofting up steel/tungsten penetrators with a small engine designed to de-orbit it plus a second stage engine to aim the thing it's very easy to kill tanks and airplanes. And unlike a laser or other direct energy weapons, heavy cloud cover does not make your wonder space weapon useless.

The disadvantage is you HAVE to do economies of scale to make KEV's useful. You have to throw thousands of them into orbit because you can only use each one once unless you design some sort of firing platform with a re-loadable magazine. But on the flip side you really need nothing more than a penetrator, an engine on one end to guide it, and some heat shielding to get down to earth in one piece with as much mass left as possible when you hit them at 13kilometers a second or so. The other issue is that KEV have to be built to order. You can't well use that half a megaton city bus sized one to kill one tank. Nor is that 2 meter human sized KEV going to do much against that enemy command and control bunker you need to kill.

But hey KEV's excel at one thing and that's killing airfields, something notoriously hard to do. But dropping a Volkswagen sized KEV is quite able to leave 121 meter across crater thats 36 meters deep. Which puts quite a dent in airfield operations never mind the side destruction as derbies rain down with a mile or so of impact.

[Admiral Valdemar]

For Teller's Rods from God, it may just be better having a spaceplane perform a dive and release numerous crowbars before boosting to orbit again. It could be just as quick, but without your system being an orbiting target. Just copy the kinetic harpoon cluster kill idea from Peter F. Hamilton and have loads of these buggers plaster a sizeable area of real estate.

[Coyote]

The ideas presented here about detonating the fuel trucks and the air-defense radars, as well as planes on the ground, are much more efficient and likely uses of such an orbital device.

Taking out a fuel truck immobilizes dozens of tanks; planes are soft-skinned and easier to destroy, and once you take out air-defense radars then your own aircraft can fly with impunity and take out whatever's left, including any pesky tanks that remain.

You can also take out any commander-type that shows himself. Especially demoralizing if you can get him a few days before the battle when he's giving his big victory rally speech to the troops on the flag-bedecked stage. Melting the enemy commander's head in front of his men is demoralizing; it gets worse if no commander will show himself publicly in the weeks before any subsequent attack and the troops start feeling like they're being left exposed to the mercies of the death rays... from there you let the psychological effects accumulate.

[Isolder74]

Not only that but we aren't talking about 1 or 2 Megawatts of power 10's 20's or up to 100's of megawatts required.

Why? Anti tank weapons hit with about a megajoule. A one megawatt generator, even accounting for inefficiency, could generate that kind of energy for one shot every ten seconds. And since it generates constantly, if you add a capacitor pool, you can do something like ten shots for ten seconds, then two minutes of recharging. (In this time, the thing probably orbitted out of the target zone anyway, so the energy generated is being wasted if not stored somehow.)

And an anti tank weapon would be completely useless attacking a ground target through the ENTIRE ATMOSPHERE OF THE PLANET!!!!! You'd need at least 10 megawatt particle or laser weapon to just be effective on the ground. To fire like you propose you need that much power available on demand something charging batteries at 1/4 of the power required will not do.

Introducing the Particle-Beam Weapon

STI

The Solar array to make 1 megawatt is big enough already now add to that the array of batteries and capacitors required to charge up to the amounts you'd need to do any real damage to a target on the ground.

Those requirements are the same with a fission reactor.

Your point being? I don't need acres of solar cells to do the same job with the Nuclear reactor.

A fission reactor would take up far less space and require less mass then would the Solar array required to get the needed power.

Less space I'll grant as obvious, though I'm not sure if being a big target is a big problem. ASAT weapons are able to kill small satellites too.

For less mass, prove it.

But it sure is harder. With a massive solar array you just have to hit a part of that to knock it out of it's orbit making it useless as a weapon. with the reactor sat you have to hit just the sat to down it a harder target.

A solar array mass wise includes, the panels themselves, the servos required to open them, the pylons to hold them in place. The International space station only produces a few dozen kilowatts(j/s) per array.

In 2005 Rigid-Panel Stretched Lens Arrays were producing 7 kW per wing. Solar arrays producing 300 W/kg and 300 W/m² from the sun's 1366 W/m² energy near the Earth are available. Entech Inc. hopes to develop 100 kW panels by 2010 and 1 MW panels by 2015. [7]

1 megawatt = 3,333 kg and 3,333 m² just for the panels using current tech. This does not include the pylons and other equipment required to just DEPLOY this massive array. I THINK IT'S UP TO YOU TO PROVE THAT A REACTOR WOULD BE MORE THEN THAT LOGISTICALLY!

I highlighted hopes as that doesn't mean they have said tech available or feasible by that time.

The more surface area a satellite has the more it will be hit by and damaged by space debris. You can't discount this problem.

It isn't that important; odds are an impact would sandblast a small portion of the panel, which takes away some power, but the un-hit parts keep working. Not a huge deal, but it might need some maintenance long term.

You don't seem to be realizing the surface area we are talking about here. More to the point every strike means repositioning your satellite back into it's desired orbit costing you fuel. Every time something is hit it lower the efficiency of the array or could possible knock it out completely depending on the location.

Acres of solar cells are not a laughing matter.

[Sea Skimmer]

Lasers off lots of advantages but you simply can't beat Rods from God for cheap methods of killing things on Earth. Lofting up steel/tungsten penetrators with a small engine designed to de-orbit it plus a second stage engine to aim the thing it's very easy to kill tanks and airplanes. And unlike a laser or other direct energy weapons, heavy cloud cover does not make your wonder space weapon useless.

Assuming you came up with a reentry guidance system accurate to within 1 meter, sure killing tanks would be easy. But reality says that's not happening with reliability and even a 5 meter CEP would be enough to cause a very high miss rate vs. tanks. Even laser guided bombs only had a roughly 1:3 kill ratio in the Gulf War because missing even slightly is enough to let the tank survive.

You seem be vastly underestimating the cost and complexity of such a system. It is by no means cheep or simple, and certainly less cheep or simple then releasing a similar projectile from a ballistic missile. You are also totally ignoring the requirement for cross range maneuverability. That takes more then a one simple one kick deorbit engine. Deorbiting is inherently less accurate then a ground to ground ballistic trajectory so you put a lot more demand on the abilities of the reentry vehicle.

The disadvantage is you HAVE to do economies of scale to make KEV's useful. You have to throw thousands of them into orbit because you can only use each one once unless you design some sort of firing platform with a re-loadable magazine. But on the flip side you really need nothing more than a penetrator, an engine on one end to guide it, and some heat shielding to get down to earth in one piece with as much mass left as possible when you hit them at 13kilometers a second or so.

You also need GUIDANCE; and the idea of reentering under active engine power, let alone enough to add 4,000 meters a second while doing so, is rather completely absurd GPS is not accurate enough for this role without differential GPS ground stations, and even then it would be sketchy since the RV will be radio blind for a period of its fall, so your going to need radar. 3,000 meters per second is a far more realistic impact speed.

But hey KEV's excel at one thing and that's killing airfields, something notoriously hard to do. But dropping a Volkswagen sized KEV is quite able to leave 121 meter across crater thats 36 meters deep. Which puts quite a dent in airfield operations never mind the side destruction as derbies rain down with a mile or so of impact.

Not really. Its is very unlikely that even a crater that big will cut both a runway and the taxiway, leaving one or the other open to fighter operations. On an airfield with a long runway cutting it in half at one point would also leave both ends long enough to serve as minimal operating stripes. That assumes the airfield only has one runway too. This is why real anti runway weapons like JP.233, Durandal and Apache use fairly small warheads, so that damage can be spread over the widest possible area with many of them dropped. Attacking the runway surface is a waste of time anyway, unless you are able to sustain the strikes to meter the flow of enemy aircraft into the air. Of course such a large orbital projectile would also easily cost 75 million dollars anyway and is plainly absurd for such a low value task of cratering a runway.

Space lasers make way more sense because they can hit moving targets almost as easily as fixed ones, and even with a chemical laser you would have a number of shots to work with. 30 or so space lasers in low orbit could give complete global coverage with near instantaneous reaction time, while even thousands of small projectiles in orbit would not be able to offer the same reaction time or coverage. The space lasers would also provide realistic air defense and ABM coverage, by far the biggest reason to put lasers in space. The ability to burn ground targets would just be a bonus really. GBI is around 65 million a shot, KEI was going to be as much as 90 million a shot, compared to that a space laser could pretty quickly justify a several billion dollar price tag blowing up aircraft and ballistic missile. The technology just isn't ready yet.

Space based microwave weapons using giant reflector AESA antennas that double as radar sets would also be real nice. Blowing up the enemy ammo by cooking the fuses will work just as well as burning the barrel off a tank.

[Sea Skimmer]

One juicy and cost effective target would be those powerful and expensive air defense radars. They are easy to detect by their emissions and their antennae are fragile.

Those big radars are a little more robust then you might think, the antennas designs are highly redundant so it won’t disable them if you just cut a slash across with a laser. Also such large fixed or semi mobile installations are more practical to defend with perpetual (as opposed to ones triggers by laser warning devices) smokescreens then mobile field troops. The Germans in WW2 and Saddam in 2003 made extensive use of city shrouding smokescreens.

A fission reactor would take up far less space and require less mass then would the Solar array required to get the needed power. The more surface area a satellite has the more it will be hit by and damaged by space debris. You can't discount this problem. A 10 Megawatt nuclear reactor would be much more practical then even a Solar Array of the same power output. The unit can have solar cells to power it's targeting systems with much more practicality then trying to power the weapon itself.

You are discounting an awful lot of problems with reactors in space, all of them in fact. Remember the bigger the fission reactor, the bigger the radiator you need to cool that reactor. Such a radiator will very quickly become too large to fit inside the booster when deployed, requiring that it unfold in orbit which is very complicated plumbing to say the least. Since you only have radiation for cooling, the thermal efficiency of the reactor will be low, which demands yet bigger radiators to deal with proportionally higher waste heat.

Such a radiator, pumped full of exotic coolant and thin walled to make it work better, will also be vulnerable to impacts and vulnerable to enemy countermeasures. Solar arrays can take a lot of damage and still work at reduced capacity, if you get one coolant leak on a reactor its game over. One Russian nuclear satellite did spring a coolant leak, and drops of that sodium coolant now make up something like 40% of all earth orbit space debris.

The radiator will also be big enough to create significant drag in a low earth orbit; though of course this is also a big problem with solar panels, but its an issue that must be dealt with. In addition since a fission reactor has a limited useful life, you need provisions for dealing with it after the end of its useful life . The Soviet solution was a booster rocket (yet more weight to throw on the satellite) which pushed the reactors into a very high orbit. This system failed more then once, in one case leading to the spacecraft crashing into Canada. The Russians abandon the reactor program and switched to solar power after that happened too.

The Russian sats were only designed for 100 day missions too, while we would want more like 10-15 years of life out of a space weapon satellite. Good luck ensuring reliability of that system; and remember if it goes wrong the reactor won't have any shielding so you can't send up human astronauts to fix it as they will die trying. A solar powered satellite meanwhile can be acceptably deorbited and left to fall into the ocean which is a much much cheaper option. If the deorbit system fails then we can wait for it to deorbit itself years later, and blow it up with an SM-3 if it looks like it might fall on a city. Of course you also have the never ending problem of WTF happens if the space booster launching the reactor blows up on the pad or otherwise crashes short of orbit. The political and environmental issues with that will always exist no matter how advanced the design.

Meanwhile such a high power nuclear reactor in space has never been done before, and would demand an immensely expensive and protracted period of research and development. The Russian nuclear reactor powered radar satellites produced only 2kw of power (this is on par with a low end fighter radar set) and used thermocouples to do so. A 10 megawatt reactor would need some kind of gas turbine setup to be remotely sane in power to weight ratio, which could cost several tens of billions of dollars to develop. A Sterling engine might be an acceptable mid point between a turbine and thermocouples, but it would still be highly inefficient. You would also need a fucking lot of sterling engines and all the maze of piping that goes with them.

That kind of absurdly massive R&D project for the power supply isn’t good when the laser system itself is already a hugely complex project. Solar panels and batteries would be purely a matter of scaling what we already have, and could be had for billions and billions of dollars less in a predictable timeframe. The groundbreaking research stuff would be purely concentrated on making the laser work.

1 megawatt of solar panels could support a 10% duty cycle of a 10 megawatt laser, which is not bad at all. It isn’t very realistic to expect the laser to fire continuously since it would almost surely overheat anyway. The main limit of solar power would be less firepower when on the dark side of the planet, but batteries are getting better by the day and latter satellites could have upgraded batteries far more easily then you could upgrade a space based reactor.

[Isolder74]

1 megawatt = 3,333 kg and 3,333 m² just for the panels using current tech. This does not include the pylons and other equipment required to just DEPLOY this massive array.

The number is for the whole array, not just the panel.

I THINK IT'S UP TO YOU TO PROVE THAT A REACTOR WOULD BE MORE THEN THAT LOGISTICALLY!

You made the claim that solar isn't up to the job. Your claim, your burden of proof.

So you've shown 300 W (electric) /kg for existing solar panels. Have a number showing existing nuclear reactors to be better?

You don't seem to be realizing the surface area we are talking about here.

I know it, but I don't care. There's plenty of space in space, and it is all pretty empty.

More to the point every strike means repositioning your satellite back into it's desired orbit costing you fuel. Every time something is hit it lower the efficiency of the array or could possible knock it out completely depending on the location.

Man, it sounds like solar power is completely unsuitable to use in space. Better fill NASA in on your brilliant deduction.

Did I say solar was unsuitable in space. NO! All I said was an array required to power an energy weapon is.

The figure I gave were for the solar cells themselves and not mounting equipment.

Sea Skimmer has made a much more coherent argument then you have.

[Sea Skimmer]

Sea Skimmer has made a much more coherent argument then you have.

And you've made no real argument at all, just a sweeping assertion, so how about you shut up or else make one before you keep wasting other peoples time.

[Isolder74]

Did I say solar was unsuitable in space. NO! All I said was an array required to power an energy weapon is.

It's the same thing.

No it isn't.

KW /= MW

Most Satellites don't use that much power.

Sea Skimmer has made a much more coherent argument then you have.

I'm not giving an argument. I'm asking you to back your's up, which you're clearly too fucking braindead to do.

Which I did.

You are not willing to accept it.

3,000 kg(over 6 tons) of payload is no laughing matter. I showed why a solar array of that capacity isn't feasible. The showing of a Reactor for the same job not being feasible is your burden of proof.

While Sea Skimmer has made a conclusive argument that neither power sources are feasible. It more or less shows that STI and space-based weapons in general are unreasonable for more then one reason. Mass required to power the weapon, the mass of the weapon itself and then mass of the equipment to cool the energy weapon.

Just launching the weapon itself without the power system is going to be profitably expensive.

[Admiral Valdemar]

Weaponised satellites are really not a good idea anyway. The only concept I'd be happy with, would be the reflector, and that still has huge hurdles. There are modern reactor designs that would allow a far smaller, more efficient weapons system, but with the problems still of a nuke in space. Likewise, solar cells are a huge target. There's really no net benefit to putting these things up there over, say, an aircraft that can have a downward facing laser or just bomb from orbit with kinetic harpoons.

So the answer to the question is yes, it's feasible. But practical and cost effective is another matter. Satellites are predictable, expensive and easy to mission kill (you don't even need an ASAT, just lase the football field sized target that passes overhead everyday and watch several million bucks of sensory hardware become useless). And no one would allow you to put these things up there anyway, and if they did, then objections over nukes in space or hazardous chemical laser reactants wouldn't really hold the water they do now.

[Isolder74]

He attacked a reactor as a power source.

I claim that solar won't work either. Pointing out Satellites using arrays of only a few 10's of meters in operation is silly.

You won't pay attention.

3,333 kg about= 7,348 pounds. I'll give you my math mistake but I will not give you on how expensive a launch weight that would be. Once again this does not include the struts and supports to hold this array. The Specs I posted were for the solar cells themselves and not mounting equipment. Only the array itself.

3333 square meters of area is required for that array. That is a space of 3333 meters by 3333 meters. That is a huge area. How would you manage to even DEPLOY an array of that size? Unless you launch this in multiple sections it isn't going to work.

This does not include the mass and volume required for the batteries and the weapon itself.

The largest array currently in operation is on the International Space Station. Each section only produces 7kw. Each 108.6-ft. long solar array wing is connected to the ISS's 310-ft. long truss and extend outward at right angles to it. Altogether, they cover an area of 27,000-sq. ft. about acre. When fully extended, a pair of wings and their associated equipment span about 240 feet, the largest deployable space structures ever built. They were launched in 4 sections. That array only produces 28 kw. This is more then the station actually needs.

To build a array with those solar units to power a energy weapon would be unimaginable.

To be viable you have to launch more then one of these weapons.

Prohibitively Expensive.

Way to take advantage of spelled right but wrong word. (and the spell checker making a correction it should not have.)