Weapons in space

[jwenting]

Yeah, and the world would benefit greatly from tungsten rods smacking the sh*t out of targets.

One of the reasons I love the fact atomic weaponry exists is the MAD doctrine which is probably the best way to ensure military morons don't destroy us all.

It's the political morons always wanting to start wars. Military people (and politicised generals and colonels like Petraeus aren't military people) generally want to avoid war, as they know what it can do and care about their people.

But yes, nuclear weapons have kept the peace (mostly) for over 65 years, something we should celebrate.

For the same reason I'm seriously concerned about the ever increasing number of robotic armed vehicles. When the risk of your boys not coming home is taken away, a very major consideration for launching a war is taken away and it starts to become solely a monetary equation "it will cost me $100 million to take out that country's oil refineries, which will yield me $200 million in increased income from my share in oil refineries in another country, let's do it".

[MarkusA380]

A small marble sized titanium ball travelling with thousands of meters per second. Effect of an nuclear bomb.

[Seret]

A small marble sized titanium ball travelling with thousands of meters per second. Effect of an nuclear bomb.

Yeah, not really. Let's say 1cm³ of tungsten, which is about 15g. At 10,000ms^-1 you'd be looking at 750kJ. That's about 6 times faster than a tank gun, but less than 10% of the kinetic energy. Current tank guns fire a penetrator of about 4kg at about 1700ms^-1. End result is around 6MJ of smash at the muzzle.

For wee bit of titanium of 1cm³ to have the equivalent of a small nuke (say 1kT) you'd need to fling it at about 7% of light speed (at which point I imagine my simply back of napkin calculation starts to break down due to relativistic effects).

[magnemoe]

It's the political morons always wanting to start wars. Military people (and politicised generals and colonels like Petraeus aren't military people) generally want to avoid war, as they know what it can do and care about their people.

But yes, nuclear weapons have kept the peace (mostly) for over 65 years, something we should celebrate.

For the same reason I'm seriously concerned about the ever increasing number of robotic armed vehicles. When the risk of your boys not coming home is taken away, a very major consideration for launching a war is taken away and it starts to become solely a monetary equation "it will cost me $100 million to take out that country's oil refineries, which will yield me $200 million in increased income from my share in oil refineries in another country, let's do it".

More that military are more careful about selecting their wars, as in can we win this easy.

About robotic, nothing really new. Why do you think every tinpot dictator is so hanged up in ballistic missiles? Its an safe way of attacking, ignoring the fact that using them will bring massive air strikes and possible an invasion.

Also hard to say how well drones will work in an larger war, they are very cost effective then the enemy don't have any air defense or electronic combat abilities but they will probably get problems against an enemy who have this. Will have their place but probably not in the front line. Smaller smart weapons on the other hand will have far more impact.

[Arbolus]

We know that using regular ballistic missiles against satellites is bad because of the dangers of Kesslerization. But would it be possible to use some sort of electromagnetic missile instead? If you put a NNEMP generator in the warhead together with conventional explosives and some means of containing the explosion, you could have the missile perform a near miss of the target, setting off a small EMP at the closest approach. Hopefully you'd fry the target's electronics without actually creating any extra debris.

Thoughts?

[Drunkrobot]

If the satellite is small enough, then why not use a ground-based laser to "push" it into a lower orbit, so it can burn up in the atmosphere?

To the person complaining about the GI Joe clip being "Hollywood science", it isn't really. It isn't made clear exactly how large the rod was, and a big enough one might be able to cause a small earthquake. And "we drop it" could be forgiven, since it does sound more dramatic than "we release it in a suborbital trajectory".

[Warshawski]

If the satellite is small enough, then why not use a ground-based laser to "push" it into a lower orbit, so it can burn up in the atmosphere?

To the person complaining about the GI Joe clip being "Hollywood science", it isn't really. It isn't made clear exactly how large the rod was, and a big enough one might be able to cause a small earthquake. And "we drop it" could be forgiven, since it does sound more dramatic than "we release it in a suborbital trajectory".

And don't forget about London's Metro system. That could very well have amplified the blast's effects.

[iDan122]

I made a military satellite called ONDS(look it up), it basically carries 4 nuclear warhead which can de-orbit, re-enter and smack a city. Might be turned into a hydrogen bomb too.

Antimatter bombs will just make some nice light but won't make any shockwaves.

Another variant is a chemical bomb. If we want to quickly decrease the population of Earth and not harm any,thing else except for humans we can use chemical payloads like in Moonraker. Millions dead and not a single exploded building. And the Earth and the atmosphere will say thank you.

[SargeRho]

An Antiproton bomb will actually make quite a massive fireball, followed by an enormous EMP, and a shockwave like you've never seen...if detonated in atmosphere. In space you get a nice gamma ray fireworks and a particle shockwave.

Edited September 9, 2013 by SargeRho

[TheSaint]

Nuclear-pumped x-ray lasers: http://en.wikipedia.org/wiki/Nuclear_pumped_laser

[jwenting]

The US asat weapon is suborbital and has to be launched to intercept.

the Soviet ASAT weapon was orbital, could be launched into orbit during escalating tension, be steered towards a target, then launch a cloud of shrapnel to destroy it.

Think the ultimate shotgun, though AFAIK it only carried one shot per weapon.

[magnemoe]

the Soviet ASAT weapon was orbital, could be launched into orbit during escalating tension, be steered towards a target, then launch a cloud of shrapnel to destroy it.

Think the ultimate shotgun, though AFAIK it only carried one shot per weapon.

The shrapnel was probably from something like an claymore mine. you set it off an the shotgun blast goes in the direction of the target, the asat satelite goes the other way in parts.

The fun part was that the gun on the space station would work well against an Soviet type asat weapon not an american, its pretty common to make your defensive system work against your own weapons not the one the enemy have. Probably as it makes testing easier.

[magnemoe]

If the satellite is small enough, then why not use a ground-based laser to "push" it into a lower orbit, so it can burn up in the atmosphere?

To the person complaining about the GI Joe clip being "Hollywood science", it isn't really. It isn't made clear exactly how large the rod was, and a big enough one might be able to cause a small earthquake. And "we drop it" could be forgiven, since it does sound more dramatic than "we release it in a suborbital trajectory".

Heating up the satellite enough to melt plastic should work well enough.

Regarding the iron man weapon, its easy to calculate the size and speed of something to make an explosion like an small nuke, stuff like the impact calculator does it well.

I agree that drop from orbit is an good enough term, and yes something who falls from 500 km attitude would have much less energy than something who was deorbitet.

However you still need an mass of around 50 ton, meteorites can be smaller as they come in faster.

[Bioman222]

Nuclear-pumped x-ray lasers: http://en.wikipedia.org/wiki/Nuclear_pumped_laser

Holy [censored]!!! I didn't even understand a third of those words, but it sounds brilliant!

[Kryten]

There's only one problem with bomb-pulsed x-ray lasers; when they tested the concept, they couldn't get it to actually work.

Edited September 11, 2013 by Kryten

[NGTOne]

There's only one problem with bomb-pulsed x-ray lasers; when they tested the concept, it didn't get it to actually work.

Reactor-pumped lasers are still under development, and show a whole bunch more promise than bomb-pumped ones. Reusable, too, which is a nice benefit.

[magnemoe]

Reactor-pumped lasers are still under development, and show a whole bunch more promise than bomb-pumped ones. Reusable, too, which is a nice benefit.

Heard about the bomb pumped one but not the reactor pumped.

Anyway main problem with bomb pumped lasers is that you has to set of an nuke to use them so the only time would be in an all out nuclear war.

[TheSaint]

There's only one problem with bomb-pulsed x-ray lasers; when they tested the concept, they couldn't get it to actually work.

The physics is all there, getting it to work is an engineering problem. If someone has the need to do it, they'll make it work.

Reactor-pumped lasers are still under development, and show a whole bunch more promise than bomb-pumped ones. Reusable, too, which is a nice benefit.

Reactors are a lot heavier than nuclear weapons, especially when you add in shielding. If you put a bomb-pumped laser on the tip of a missile that you weren't planning on getting back anyway, you're good to go.

Heard about the bomb pumped one but not the reactor pumped.

Anyway main problem with bomb pumped lasers is that you has to set of an nuke to use them so the only time would be in an all out nuclear war.

Depends on how and where you're using them. If you're using them to attack enemy spacecraft in deep space I doubt that anyone would take that as an excuse to launch ICBMs against their opponent's cities.

Edited September 11, 2013 by TheSaint

[Seret]

If you put a bomb-pumped laser on the tip of a missile that you weren't planning on getting back anyway, you're good to go.

If you're carrying an explosive in your warhead why use it to power a laser? Unless the process of converting the chemical energy into the laser was 100% efficient you'd be losing effect.

[Kryten]

That's like asking why people use gunpowder to propel bullets instead of throwing paper cartridges at people. In space a nuclear bomb is almost useless unless it reaches point-blank range, and it may not be terribly useful even then, depending on the level of shielding in the target craft.

[TheSaint]

If you're carrying an explosive in your warhead why use it to power a laser? Unless the process of converting the chemical energy into the laser was 100% efficient you'd be losing effect.

Two reasons:

1. As said above, nuclear weapons are nowhere near as effective in space as they are on the ground. On the ground most of the damage caused by a nuclear weapon is from superheating the air and creating a shockwave that causes damage through overpressure and thermal effects. In space, the only mass the bomb has to work with is its own, so the shockwave is minimal, and the only thermal effects are through heating of the target's surface by radiation. By using a nuclear-pumped laser you take the one thing that the bomb produces in abundance (radiation) and turn it into a very powerful directed-energy weapon.

2. The other thing the nuclear laser does is it turns your missile into a stand-off weapon. If your target is equipped with its own laser weapons, it would be very easy for them to pick off a conventional missile as it tries to close to an effective range. They can shred the missile with a point-defense laser, then execute a quick course change to avoid the debris. But if your missile's warhead is actually a laser that is far more powerful than any FEL or chemical laser that can be carried on a ship, you can detonate it outside of the effective range of the target's point defenses and stand a much better chance of inflicting damage on the target.

[Seret]

If your target is equipped with its own laser weapons, it would be very easy for them to pick off a conventional missile as it tries to close to an effective range.

Lasers aren't really very effective at that. There have been some demonstrations of chemical lasers that are able to defeat artillery rockets and mortars on a ballistic trajectory, but these are attacks at an angle to that trajectory (ie: they don;t have to kill the incoming projectile by acting on its tiny frontal cross-section). There's no laser that can defeat an incoming missile head on. Guns and other missiles however are able to do this, and for a tiny fraction of the size and weight.

I don't think you're likely to see point defences of any kind on space vehicles though. Similar to aircraft, stealth, speed and countermeasures are going to be more effective on a vehicle that has to be lightweight.

[Kryten]

There's no stealth in space.

[TheSaint]

Lasers aren't really very effective at that. There have been some demonstrations of chemical lasers that are able to defeat artillery rockets and mortars on a ballistic trajectory, but these are attacks at an angle to that trajectory (ie: they don;t have to kill the incoming projectile by acting on its tiny frontal cross-section). There's no laser that can defeat an incoming missile head on. Guns and other missiles however are able to do this, and for a tiny fraction of the size and weight.

I don't think you're likely to see point defences of any kind on space vehicles though. Similar to aircraft, stealth, speed and countermeasures are going to be more effective on a vehicle that has to be lightweight.

You're assuming that laser technology won't advance at all between now and the time that we are fighting wars in deep space? That's a bit of a stretch. Projectiles will work for a point defense system, but a laser will do it better. So when it becomes an issue, someone will find a way.

And as for stealth, that's a big stretch in space. You can mask radar signatures like on stealth aircraft, but your infrared signature is what is really going to kill you. Your ship itself will emit a ton of infrared from waste heat, but that could be temporarily mitigated by using some sort of internal heat sink. However, the minute you turn on any engine of any significance you will project a giant plume of infrared-emitting exhaust that will be easily visible over a very long distance. And when you turn the engine off you will be a sitting duck until you turn the engine on again.

Speed may help you a bit, but you're never going to be able to develop a manned spacecraft that will have a higher acceleration than an unmanned missile with the same engine technology. You will have more delta-v in a larger ship, but that will only get you so far. The enemy can just keep sending missiles for you to outrun until they wear down your fuel supply. You will eventually have to stand and fight, so you might as well get it over with.

Electronic countermeasures (in the sense that we use them now) will also be useless. Anything you transmit in the electromagnetic spectrum is going to do nothing but help your opponent pinpoint your position. You might be able to use decoys effectively, but remember that every decoy you carry is more weight that isn't fuel or weapons. I suppose that a wide-beam infrared laser could be an effective countermeasure, you could use it to flood your opponent's IR sensors while you're maneuvering. But you're probably better off spending that weight on something that can kill them instead.

[Aghanim]

One of the powerful weapon: ISV Venture Star orbital laser gun for propelling the interstellar photon sail. Imagine your ship getting beamed by multi petawatt CW laser...

And if we have a source of huge thrust (Orion drive) than you could pretty much ignore the mass problem anyway (1300 metric tons)